2688 lines
133 KiB
HTML
2688 lines
133 KiB
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<link href="Machine-Desc.html#Machine-Desc" rel="up" title="Machine Desc">
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<a name="Standard-Names"></a>
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<p>
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Next: <a href="Pattern-Ordering.html#Pattern-Ordering" accesskey="n" rel="next">Pattern Ordering</a>, Previous: <a href="Constraints.html#Constraints" accesskey="p" rel="prev">Constraints</a>, Up: <a href="Machine-Desc.html#Machine-Desc" accesskey="u" rel="up">Machine Desc</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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</div>
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<hr>
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<a name="Standard-Pattern-Names-For-Generation"></a>
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<h3 class="section">16.9 Standard Pattern Names For Generation</h3>
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<a name="index-standard-pattern-names"></a>
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<a name="index-pattern-names"></a>
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<a name="index-names_002c-pattern"></a>
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<p>Here is a table of the instruction names that are meaningful in the RTL
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generation pass of the compiler. Giving one of these names to an
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instruction pattern tells the RTL generation pass that it can use the
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pattern to accomplish a certain task.
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</p>
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<dl compact="compact">
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<dd><a name="index-movm-instruction-pattern"></a>
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</dd>
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<dt>‘<samp>mov<var>m</var></samp>’</dt>
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<dd><p>Here <var>m</var> stands for a two-letter machine mode name, in lowercase.
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This instruction pattern moves data with that machine mode from operand
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1 to operand 0. For example, ‘<samp>movsi</samp>’ moves full-word data.
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</p>
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<p>If operand 0 is a <code>subreg</code> with mode <var>m</var> of a register whose
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own mode is wider than <var>m</var>, the effect of this instruction is
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to store the specified value in the part of the register that corresponds
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to mode <var>m</var>. Bits outside of <var>m</var>, but which are within the
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same target word as the <code>subreg</code> are undefined. Bits which are
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outside the target word are left unchanged.
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</p>
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<p>This class of patterns is special in several ways. First of all, each
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of these names up to and including full word size <em>must</em> be defined,
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because there is no other way to copy a datum from one place to another.
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If there are patterns accepting operands in larger modes,
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‘<samp>mov<var>m</var></samp>’ must be defined for integer modes of those sizes.
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</p>
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<p>Second, these patterns are not used solely in the RTL generation pass.
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Even the reload pass can generate move insns to copy values from stack
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slots into temporary registers. When it does so, one of the operands is
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a hard register and the other is an operand that can need to be reloaded
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into a register.
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</p>
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<a name="index-force_005freg"></a>
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<p>Therefore, when given such a pair of operands, the pattern must generate
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RTL which needs no reloading and needs no temporary registers—no
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registers other than the operands. For example, if you support the
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pattern with a <code>define_expand</code>, then in such a case the
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<code>define_expand</code> mustn’t call <code>force_reg</code> or any other such
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function which might generate new pseudo registers.
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</p>
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<p>This requirement exists even for subword modes on a RISC machine where
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fetching those modes from memory normally requires several insns and
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some temporary registers.
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</p>
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<a name="index-change_005faddress"></a>
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<p>During reload a memory reference with an invalid address may be passed
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as an operand. Such an address will be replaced with a valid address
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later in the reload pass. In this case, nothing may be done with the
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address except to use it as it stands. If it is copied, it will not be
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replaced with a valid address. No attempt should be made to make such
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an address into a valid address and no routine (such as
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<code>change_address</code>) that will do so may be called. Note that
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<code>general_operand</code> will fail when applied to such an address.
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</p>
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<a name="index-reload_005fin_005fprogress"></a>
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<p>The global variable <code>reload_in_progress</code> (which must be explicitly
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declared if required) can be used to determine whether such special
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handling is required.
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</p>
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<p>The variety of operands that have reloads depends on the rest of the
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machine description, but typically on a RISC machine these can only be
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pseudo registers that did not get hard registers, while on other
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machines explicit memory references will get optional reloads.
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</p>
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<p>If a scratch register is required to move an object to or from memory,
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it can be allocated using <code>gen_reg_rtx</code> prior to life analysis.
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</p>
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<p>If there are cases which need scratch registers during or after reload,
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you must provide an appropriate secondary_reload target hook.
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</p>
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<a name="index-can_005fcreate_005fpseudo_005fp"></a>
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<p>The macro <code>can_create_pseudo_p</code> can be used to determine if it
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is unsafe to create new pseudo registers. If this variable is nonzero, then
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it is unsafe to call <code>gen_reg_rtx</code> to allocate a new pseudo.
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</p>
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<p>The constraints on a ‘<samp>mov<var>m</var></samp>’ must permit moving any hard
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register to any other hard register provided that
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<code>HARD_REGNO_MODE_OK</code> permits mode <var>m</var> in both registers and
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<code>TARGET_REGISTER_MOVE_COST</code> applied to their classes returns a value
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of 2.
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</p>
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<p>It is obligatory to support floating point ‘<samp>mov<var>m</var></samp>’
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instructions into and out of any registers that can hold fixed point
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values, because unions and structures (which have modes <code>SImode</code> or
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<code>DImode</code>) can be in those registers and they may have floating
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point members.
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</p>
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<p>There may also be a need to support fixed point ‘<samp>mov<var>m</var></samp>’
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instructions in and out of floating point registers. Unfortunately, I
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have forgotten why this was so, and I don’t know whether it is still
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true. If <code>HARD_REGNO_MODE_OK</code> rejects fixed point values in
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floating point registers, then the constraints of the fixed point
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‘<samp>mov<var>m</var></samp>’ instructions must be designed to avoid ever trying to
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reload into a floating point register.
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</p>
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<a name="index-reload_005fin-instruction-pattern"></a>
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<a name="index-reload_005fout-instruction-pattern"></a>
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</dd>
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<dt>‘<samp>reload_in<var>m</var></samp>’</dt>
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<dt>‘<samp>reload_out<var>m</var></samp>’</dt>
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<dd><p>These named patterns have been obsoleted by the target hook
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<code>secondary_reload</code>.
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</p>
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<p>Like ‘<samp>mov<var>m</var></samp>’, but used when a scratch register is required to
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move between operand 0 and operand 1. Operand 2 describes the scratch
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register. See the discussion of the <code>SECONDARY_RELOAD_CLASS</code>
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macro in see <a href="Register-Classes.html#Register-Classes">Register Classes</a>.
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</p>
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<p>There are special restrictions on the form of the <code>match_operand</code>s
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used in these patterns. First, only the predicate for the reload
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operand is examined, i.e., <code>reload_in</code> examines operand 1, but not
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the predicates for operand 0 or 2. Second, there may be only one
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alternative in the constraints. Third, only a single register class
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letter may be used for the constraint; subsequent constraint letters
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are ignored. As a special exception, an empty constraint string
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matches the <code>ALL_REGS</code> register class. This may relieve ports
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of the burden of defining an <code>ALL_REGS</code> constraint letter just
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for these patterns.
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</p>
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<a name="index-movstrictm-instruction-pattern"></a>
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</dd>
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<dt>‘<samp>movstrict<var>m</var></samp>’</dt>
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<dd><p>Like ‘<samp>mov<var>m</var></samp>’ except that if operand 0 is a <code>subreg</code>
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with mode <var>m</var> of a register whose natural mode is wider,
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the ‘<samp>movstrict<var>m</var></samp>’ instruction is guaranteed not to alter
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any of the register except the part which belongs to mode <var>m</var>.
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</p>
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<a name="index-movmisalignm-instruction-pattern"></a>
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</dd>
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<dt>‘<samp>movmisalign<var>m</var></samp>’</dt>
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<dd><p>This variant of a move pattern is designed to load or store a value
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from a memory address that is not naturally aligned for its mode.
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For a store, the memory will be in operand 0; for a load, the memory
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will be in operand 1. The other operand is guaranteed not to be a
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memory, so that it’s easy to tell whether this is a load or store.
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</p>
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<p>This pattern is used by the autovectorizer, and when expanding a
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<code>MISALIGNED_INDIRECT_REF</code> expression.
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</p>
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<a name="index-load_005fmultiple-instruction-pattern"></a>
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</dd>
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<dt>‘<samp>load_multiple</samp>’</dt>
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<dd><p>Load several consecutive memory locations into consecutive registers.
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Operand 0 is the first of the consecutive registers, operand 1
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is the first memory location, and operand 2 is a constant: the
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number of consecutive registers.
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</p>
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<p>Define this only if the target machine really has such an instruction;
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do not define this if the most efficient way of loading consecutive
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registers from memory is to do them one at a time.
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</p>
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<p>On some machines, there are restrictions as to which consecutive
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registers can be stored into memory, such as particular starting or
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ending register numbers or only a range of valid counts. For those
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machines, use a <code>define_expand</code> (see <a href="Expander-Definitions.html#Expander-Definitions">Expander Definitions</a>)
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and make the pattern fail if the restrictions are not met.
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</p>
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<p>Write the generated insn as a <code>parallel</code> with elements being a
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<code>set</code> of one register from the appropriate memory location (you may
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also need <code>use</code> or <code>clobber</code> elements). Use a
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<code>match_parallel</code> (see <a href="RTL-Template.html#RTL-Template">RTL Template</a>) to recognize the insn. See
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<samp>rs6000.md</samp> for examples of the use of this insn pattern.
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</p>
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<a name="index-store_005fmultiple-instruction-pattern"></a>
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</dd>
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<dt>‘<samp>store_multiple</samp>’</dt>
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<dd><p>Similar to ‘<samp>load_multiple</samp>’, but store several consecutive registers
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into consecutive memory locations. Operand 0 is the first of the
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consecutive memory locations, operand 1 is the first register, and
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operand 2 is a constant: the number of consecutive registers.
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</p>
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<a name="index-vec_005fload_005flanesmn-instruction-pattern"></a>
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</dd>
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<dt>‘<samp>vec_load_lanes<var>m</var><var>n</var></samp>’</dt>
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<dd><p>Perform an interleaved load of several vectors from memory operand 1
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into register operand 0. Both operands have mode <var>m</var>. The register
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operand is viewed as holding consecutive vectors of mode <var>n</var>,
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while the memory operand is a flat array that contains the same number
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of elements. The operation is equivalent to:
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</p>
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<div class="smallexample">
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<pre class="smallexample">int c = GET_MODE_SIZE (<var>m</var>) / GET_MODE_SIZE (<var>n</var>);
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for (j = 0; j < GET_MODE_NUNITS (<var>n</var>); j++)
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for (i = 0; i < c; i++)
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operand0[i][j] = operand1[j * c + i];
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</pre></div>
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<p>For example, ‘<samp>vec_load_lanestiv4hi</samp>’ loads 8 16-bit values
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from memory into a register of mode ‘<samp>TI</samp>’. The register
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contains two consecutive vectors of mode ‘<samp>V4HI</samp>’.
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</p>
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<p>This pattern can only be used if:
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</p><div class="smallexample">
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<pre class="smallexample">TARGET_ARRAY_MODE_SUPPORTED_P (<var>n</var>, <var>c</var>)
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</pre></div>
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<p>is true. GCC assumes that, if a target supports this kind of
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instruction for some mode <var>n</var>, it also supports unaligned
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loads for vectors of mode <var>n</var>.
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</p>
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<p>This pattern is not allowed to <code>FAIL</code>.
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</p>
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<a name="index-vec_005fstore_005flanesmn-instruction-pattern"></a>
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</dd>
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<dt>‘<samp>vec_store_lanes<var>m</var><var>n</var></samp>’</dt>
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<dd><p>Equivalent to ‘<samp>vec_load_lanes<var>m</var><var>n</var></samp>’, with the memory
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and register operands reversed. That is, the instruction is
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equivalent to:
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</p>
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<div class="smallexample">
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<pre class="smallexample">int c = GET_MODE_SIZE (<var>m</var>) / GET_MODE_SIZE (<var>n</var>);
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for (j = 0; j < GET_MODE_NUNITS (<var>n</var>); j++)
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for (i = 0; i < c; i++)
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operand0[j * c + i] = operand1[i][j];
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</pre></div>
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<p>for a memory operand 0 and register operand 1.
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</p>
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<p>This pattern is not allowed to <code>FAIL</code>.
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</p>
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|
<a name="index-vec_005fsetm-instruction-pattern"></a>
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</dd>
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|
<dt>‘<samp>vec_set<var>m</var></samp>’</dt>
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<dd><p>Set given field in the vector value. Operand 0 is the vector to modify,
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operand 1 is new value of field and operand 2 specify the field index.
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</p>
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<a name="index-vec_005fextractm-instruction-pattern"></a>
|
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</dd>
|
|
<dt>‘<samp>vec_extract<var>m</var></samp>’</dt>
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<dd><p>Extract given field from the vector value. Operand 1 is the vector, operand 2
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specify field index and operand 0 place to store value into.
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</p>
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<a name="index-vec_005finitm-instruction-pattern"></a>
|
|
</dd>
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<dt>‘<samp>vec_init<var>m</var></samp>’</dt>
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<dd><p>Initialize the vector to given values. Operand 0 is the vector to initialize
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and operand 1 is parallel containing values for individual fields.
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</p>
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<a name="index-vec_005fcmpmn-instruction-pattern"></a>
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|
</dd>
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<dt>‘<samp>vec_cmp<var>m</var><var>n</var></samp>’</dt>
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<dd><p>Output a vector comparison. Operand 0 of mode <var>n</var> is the destination for
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|
predicate in operand 1 which is a signed vector comparison with operands of
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mode <var>m</var> in operands 2 and 3. Predicate is computed by element-wise
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|
evaluation of the vector comparison with a truth value of all-ones and a false
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value of all-zeros.
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</p>
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<a name="index-vec_005fcmpumn-instruction-pattern"></a>
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</dd>
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<dt>‘<samp>vec_cmpu<var>m</var><var>n</var></samp>’</dt>
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<dd><p>Similar to <code>vec_cmp<var>m</var><var>n</var></code> but perform unsigned vector comparison.
|
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</p>
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<a name="index-vcondmn-instruction-pattern"></a>
|
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</dd>
|
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<dt>‘<samp>vcond<var>m</var><var>n</var></samp>’</dt>
|
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<dd><p>Output a conditional vector move. Operand 0 is the destination to
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receive a combination of operand 1 and operand 2, which are of mode <var>m</var>,
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|
dependent on the outcome of the predicate in operand 3 which is a signed
|
|
vector comparison with operands of mode <var>n</var> in operands 4 and 5. The
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modes <var>m</var> and <var>n</var> should have the same size. Operand 0
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will be set to the value <var>op1</var> & <var>msk</var> | <var>op2</var> & ~<var>msk</var>
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where <var>msk</var> is computed by element-wise evaluation of the vector
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comparison with a truth value of all-ones and a false value of all-zeros.
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</p>
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<a name="index-vcondumn-instruction-pattern"></a>
|
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</dd>
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<dt>‘<samp>vcondu<var>m</var><var>n</var></samp>’</dt>
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<dd><p>Similar to <code>vcond<var>m</var><var>n</var></code> but performs unsigned vector
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comparison.
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</p>
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<a name="index-vcond_005fmask_005fmn-instruction-pattern"></a>
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</dd>
|
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<dt>‘<samp>vcond_mask_<var>m</var><var>n</var></samp>’</dt>
|
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<dd><p>Similar to <code>vcond<var>m</var><var>n</var></code> but operand 3 holds a pre-computed
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result of vector comparison.
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</p>
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<a name="index-maskloadmn-instruction-pattern"></a>
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</dd>
|
|
<dt>‘<samp>maskload<var>m</var><var>n</var></samp>’</dt>
|
|
<dd><p>Perform a masked load of vector from memory operand 1 of mode <var>m</var>
|
|
into register operand 0. Mask is provided in register operand 2 of
|
|
mode <var>n</var>.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-maskstoremn-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>maskstore<var>m</var><var>n</var></samp>’</dt>
|
|
<dd><p>Perform a masked store of vector from register operand 1 of mode <var>m</var>
|
|
into memory operand 0. Mask is provided in register operand 2 of
|
|
mode <var>n</var>.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-vec_005fpermm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>vec_perm<var>m</var></samp>’</dt>
|
|
<dd><p>Output a (variable) vector permutation. Operand 0 is the destination
|
|
to receive elements from operand 1 and operand 2, which are of mode
|
|
<var>m</var>. Operand 3 is the <em>selector</em>. It is an integral mode
|
|
vector of the same width and number of elements as mode <var>m</var>.
|
|
</p>
|
|
<p>The input elements are numbered from 0 in operand 1 through
|
|
<em>2*<var>N</var>-1</em> in operand 2. The elements of the selector must
|
|
be computed modulo <em>2*<var>N</var></em>. Note that if
|
|
<code>rtx_equal_p(operand1, operand2)</code>, this can be implemented
|
|
with just operand 1 and selector elements modulo <var>N</var>.
|
|
</p>
|
|
<p>In order to make things easy for a number of targets, if there is no
|
|
‘<samp>vec_perm</samp>’ pattern for mode <var>m</var>, but there is for mode <var>q</var>
|
|
where <var>q</var> is a vector of <code>QImode</code> of the same width as <var>m</var>,
|
|
the middle-end will lower the mode <var>m</var> <code>VEC_PERM_EXPR</code> to
|
|
mode <var>q</var>.
|
|
</p>
|
|
<a name="index-vec_005fperm_005fconstm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>vec_perm_const<var>m</var></samp>’</dt>
|
|
<dd><p>Like ‘<samp>vec_perm</samp>’ except that the permutation is a compile-time
|
|
constant. That is, operand 3, the <em>selector</em>, is a <code>CONST_VECTOR</code>.
|
|
</p>
|
|
<p>Some targets cannot perform a permutation with a variable selector,
|
|
but can efficiently perform a constant permutation. Further, the
|
|
target hook <code>vec_perm_ok</code> is queried to determine if the
|
|
specific constant permutation is available efficiently; the named
|
|
pattern is never expanded without <code>vec_perm_ok</code> returning true.
|
|
</p>
|
|
<p>There is no need for a target to supply both ‘<samp>vec_perm<var>m</var></samp>’
|
|
and ‘<samp>vec_perm_const<var>m</var></samp>’ if the former can trivially implement
|
|
the operation with, say, the vector constant loaded into a register.
|
|
</p>
|
|
<a name="index-pushm1-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>push<var>m</var>1</samp>’</dt>
|
|
<dd><p>Output a push instruction. Operand 0 is value to push. Used only when
|
|
<code>PUSH_ROUNDING</code> is defined. For historical reason, this pattern may be
|
|
missing and in such case an <code>mov</code> expander is used instead, with a
|
|
<code>MEM</code> expression forming the push operation. The <code>mov</code> expander
|
|
method is deprecated.
|
|
</p>
|
|
<a name="index-addm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>add<var>m</var>3</samp>’</dt>
|
|
<dd><p>Add operand 2 and operand 1, storing the result in operand 0. All operands
|
|
must have mode <var>m</var>. This can be used even on two-address machines, by
|
|
means of constraints requiring operands 1 and 0 to be the same location.
|
|
</p>
|
|
<a name="index-ssaddm3-instruction-pattern"></a>
|
|
<a name="index-usaddm3-instruction-pattern"></a>
|
|
<a name="index-subm3-instruction-pattern"></a>
|
|
<a name="index-sssubm3-instruction-pattern"></a>
|
|
<a name="index-ussubm3-instruction-pattern"></a>
|
|
<a name="index-mulm3-instruction-pattern"></a>
|
|
<a name="index-ssmulm3-instruction-pattern"></a>
|
|
<a name="index-usmulm3-instruction-pattern"></a>
|
|
<a name="index-divm3-instruction-pattern"></a>
|
|
<a name="index-ssdivm3-instruction-pattern"></a>
|
|
<a name="index-udivm3-instruction-pattern"></a>
|
|
<a name="index-usdivm3-instruction-pattern"></a>
|
|
<a name="index-modm3-instruction-pattern"></a>
|
|
<a name="index-umodm3-instruction-pattern"></a>
|
|
<a name="index-uminm3-instruction-pattern"></a>
|
|
<a name="index-umaxm3-instruction-pattern"></a>
|
|
<a name="index-andm3-instruction-pattern"></a>
|
|
<a name="index-iorm3-instruction-pattern"></a>
|
|
<a name="index-xorm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>ssadd<var>m</var>3</samp>’, ‘<samp>usadd<var>m</var>3</samp>’</dt>
|
|
<dt>‘<samp>sub<var>m</var>3</samp>’, ‘<samp>sssub<var>m</var>3</samp>’, ‘<samp>ussub<var>m</var>3</samp>’</dt>
|
|
<dt>‘<samp>mul<var>m</var>3</samp>’, ‘<samp>ssmul<var>m</var>3</samp>’, ‘<samp>usmul<var>m</var>3</samp>’</dt>
|
|
<dt>‘<samp>div<var>m</var>3</samp>’, ‘<samp>ssdiv<var>m</var>3</samp>’</dt>
|
|
<dt>‘<samp>udiv<var>m</var>3</samp>’, ‘<samp>usdiv<var>m</var>3</samp>’</dt>
|
|
<dt>‘<samp>mod<var>m</var>3</samp>’, ‘<samp>umod<var>m</var>3</samp>’</dt>
|
|
<dt>‘<samp>umin<var>m</var>3</samp>’, ‘<samp>umax<var>m</var>3</samp>’</dt>
|
|
<dt>‘<samp>and<var>m</var>3</samp>’, ‘<samp>ior<var>m</var>3</samp>’, ‘<samp>xor<var>m</var>3</samp>’</dt>
|
|
<dd><p>Similar, for other arithmetic operations.
|
|
</p>
|
|
<a name="index-addvm4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>addv<var>m</var>4</samp>’</dt>
|
|
<dd><p>Like <code>add<var>m</var>3</code> but takes a <code>code_label</code> as operand 3 and
|
|
emits code to jump to it if signed overflow occurs during the addition.
|
|
This pattern is used to implement the built-in functions performing
|
|
signed integer addition with overflow checking.
|
|
</p>
|
|
<a name="index-subvm4-instruction-pattern"></a>
|
|
<a name="index-mulvm4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>subv<var>m</var>4</samp>’, ‘<samp>mulv<var>m</var>4</samp>’</dt>
|
|
<dd><p>Similar, for other signed arithmetic operations.
|
|
</p>
|
|
<a name="index-uaddvm4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>uaddv<var>m</var>4</samp>’</dt>
|
|
<dd><p>Like <code>addv<var>m</var>4</code> but for unsigned addition. That is to
|
|
say, the operation is the same as signed addition but the jump
|
|
is taken only on unsigned overflow.
|
|
</p>
|
|
<a name="index-usubvm4-instruction-pattern"></a>
|
|
<a name="index-umulvm4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>usubv<var>m</var>4</samp>’, ‘<samp>umulv<var>m</var>4</samp>’</dt>
|
|
<dd><p>Similar, for other unsigned arithmetic operations.
|
|
</p>
|
|
<a name="index-addptrm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>addptr<var>m</var>3</samp>’</dt>
|
|
<dd><p>Like <code>add<var>m</var>3</code> but is guaranteed to only be used for address
|
|
calculations. The expanded code is not allowed to clobber the
|
|
condition code. It only needs to be defined if <code>add<var>m</var>3</code>
|
|
sets the condition code. If adds used for address calculations and
|
|
normal adds are not compatible it is required to expand a distinct
|
|
pattern (e.g. using an unspec). The pattern is used by LRA to emit
|
|
address calculations. <code>add<var>m</var>3</code> is used if
|
|
<code>addptr<var>m</var>3</code> is not defined.
|
|
</p>
|
|
<a name="index-fmam4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>fma<var>m</var>4</samp>’</dt>
|
|
<dd><p>Multiply operand 2 and operand 1, then add operand 3, storing the
|
|
result in operand 0 without doing an intermediate rounding step. All
|
|
operands must have mode <var>m</var>. This pattern is used to implement
|
|
the <code>fma</code>, <code>fmaf</code>, and <code>fmal</code> builtin functions from
|
|
the ISO C99 standard.
|
|
</p>
|
|
<a name="index-fmsm4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>fms<var>m</var>4</samp>’</dt>
|
|
<dd><p>Like <code>fma<var>m</var>4</code>, except operand 3 subtracted from the
|
|
product instead of added to the product. This is represented
|
|
in the rtl as
|
|
</p>
|
|
<div class="smallexample">
|
|
<pre class="smallexample">(fma:<var>m</var> <var>op1</var> <var>op2</var> (neg:<var>m</var> <var>op3</var>))
|
|
</pre></div>
|
|
|
|
<a name="index-fnmam4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>fnma<var>m</var>4</samp>’</dt>
|
|
<dd><p>Like <code>fma<var>m</var>4</code> except that the intermediate product
|
|
is negated before being added to operand 3. This is represented
|
|
in the rtl as
|
|
</p>
|
|
<div class="smallexample">
|
|
<pre class="smallexample">(fma:<var>m</var> (neg:<var>m</var> <var>op1</var>) <var>op2</var> <var>op3</var>)
|
|
</pre></div>
|
|
|
|
<a name="index-fnmsm4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>fnms<var>m</var>4</samp>’</dt>
|
|
<dd><p>Like <code>fms<var>m</var>4</code> except that the intermediate product
|
|
is negated before subtracting operand 3. This is represented
|
|
in the rtl as
|
|
</p>
|
|
<div class="smallexample">
|
|
<pre class="smallexample">(fma:<var>m</var> (neg:<var>m</var> <var>op1</var>) <var>op2</var> (neg:<var>m</var> <var>op3</var>))
|
|
</pre></div>
|
|
|
|
<a name="index-minm3-instruction-pattern"></a>
|
|
<a name="index-maxm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>smin<var>m</var>3</samp>’, ‘<samp>smax<var>m</var>3</samp>’</dt>
|
|
<dd><p>Signed minimum and maximum operations. When used with floating point,
|
|
if both operands are zeros, or if either operand is <code>NaN</code>, then
|
|
it is unspecified which of the two operands is returned as the result.
|
|
</p>
|
|
<a name="index-fminm3-instruction-pattern"></a>
|
|
<a name="index-fmaxm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>fmin<var>m</var>3</samp>’, ‘<samp>fmax<var>m</var>3</samp>’</dt>
|
|
<dd><p>IEEE-conformant minimum and maximum operations. If one operand is a quiet
|
|
<code>NaN</code>, then the other operand is returned. If both operands are quiet
|
|
<code>NaN</code>, then a quiet <code>NaN</code> is returned. In the case when gcc supports
|
|
signaling <code>NaN</code> (-fsignaling-nans) an invalid floating point exception is
|
|
raised and a quiet <code>NaN</code> is returned.
|
|
</p>
|
|
<p>All operands have mode <var>m</var>, which is a scalar or vector
|
|
floating-point mode. These patterns are not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-reduc_005fsmin_005fscal_005fm-instruction-pattern"></a>
|
|
<a name="index-reduc_005fsmax_005fscal_005fm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>reduc_smin_scal_<var>m</var></samp>’, ‘<samp>reduc_smax_scal_<var>m</var></samp>’</dt>
|
|
<dd><p>Find the signed minimum/maximum of the elements of a vector. The vector is
|
|
operand 1, and operand 0 is the scalar result, with mode equal to the mode of
|
|
the elements of the input vector.
|
|
</p>
|
|
<a name="index-reduc_005fumin_005fscal_005fm-instruction-pattern"></a>
|
|
<a name="index-reduc_005fumax_005fscal_005fm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>reduc_umin_scal_<var>m</var></samp>’, ‘<samp>reduc_umax_scal_<var>m</var></samp>’</dt>
|
|
<dd><p>Find the unsigned minimum/maximum of the elements of a vector. The vector is
|
|
operand 1, and operand 0 is the scalar result, with mode equal to the mode of
|
|
the elements of the input vector.
|
|
</p>
|
|
<a name="index-reduc_005fplus_005fscal_005fm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>reduc_plus_scal_<var>m</var></samp>’</dt>
|
|
<dd><p>Compute the sum of the elements of a vector. The vector is operand 1, and
|
|
operand 0 is the scalar result, with mode equal to the mode of the elements of
|
|
the input vector.
|
|
</p>
|
|
<a name="index-sdot_005fprodm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>sdot_prod<var>m</var></samp>’</dt>
|
|
<dd><a name="index-udot_005fprodm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>udot_prod<var>m</var></samp>’</dt>
|
|
<dd><p>Compute the sum of the products of two signed/unsigned elements.
|
|
Operand 1 and operand 2 are of the same mode. Their product, which is of a
|
|
wider mode, is computed and added to operand 3. Operand 3 is of a mode equal or
|
|
wider than the mode of the product. The result is placed in operand 0, which
|
|
is of the same mode as operand 3.
|
|
</p>
|
|
<a name="index-ssadm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>ssad<var>m</var></samp>’</dt>
|
|
<dd><a name="index-usadm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>usad<var>m</var></samp>’</dt>
|
|
<dd><p>Compute the sum of absolute differences of two signed/unsigned elements.
|
|
Operand 1 and operand 2 are of the same mode. Their absolute difference, which
|
|
is of a wider mode, is computed and added to operand 3. Operand 3 is of a mode
|
|
equal or wider than the mode of the absolute difference. The result is placed
|
|
in operand 0, which is of the same mode as operand 3.
|
|
</p>
|
|
<a name="index-widen_005fssumm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>widen_ssum<var>m3</var></samp>’</dt>
|
|
<dd><a name="index-widen_005fusumm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>widen_usum<var>m3</var></samp>’</dt>
|
|
<dd><p>Operands 0 and 2 are of the same mode, which is wider than the mode of
|
|
operand 1. Add operand 1 to operand 2 and place the widened result in
|
|
operand 0. (This is used express accumulation of elements into an accumulator
|
|
of a wider mode.)
|
|
</p>
|
|
<a name="index-vec_005fshr_005fm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>vec_shr_<var>m</var></samp>’</dt>
|
|
<dd><p>Whole vector right shift in bits, i.e. towards element 0.
|
|
Operand 1 is a vector to be shifted.
|
|
Operand 2 is an integer shift amount in bits.
|
|
Operand 0 is where the resulting shifted vector is stored.
|
|
The output and input vectors should have the same modes.
|
|
</p>
|
|
<a name="index-vec_005fpack_005ftrunc_005fm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>vec_pack_trunc_<var>m</var></samp>’</dt>
|
|
<dd><p>Narrow (demote) and merge the elements of two vectors. Operands 1 and 2
|
|
are vectors of the same mode having N integral or floating point elements
|
|
of size S. Operand 0 is the resulting vector in which 2*N elements of
|
|
size N/2 are concatenated after narrowing them down using truncation.
|
|
</p>
|
|
<a name="index-vec_005fpack_005fssat_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005fpack_005fusat_005fm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>vec_pack_ssat_<var>m</var></samp>’, ‘<samp>vec_pack_usat_<var>m</var></samp>’</dt>
|
|
<dd><p>Narrow (demote) and merge the elements of two vectors. Operands 1 and 2
|
|
are vectors of the same mode having N integral elements of size S.
|
|
Operand 0 is the resulting vector in which the elements of the two input
|
|
vectors are concatenated after narrowing them down using signed/unsigned
|
|
saturating arithmetic.
|
|
</p>
|
|
<a name="index-vec_005fpack_005fsfix_005ftrunc_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005fpack_005fufix_005ftrunc_005fm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>vec_pack_sfix_trunc_<var>m</var></samp>’, ‘<samp>vec_pack_ufix_trunc_<var>m</var></samp>’</dt>
|
|
<dd><p>Narrow, convert to signed/unsigned integral type and merge the elements
|
|
of two vectors. Operands 1 and 2 are vectors of the same mode having N
|
|
floating point elements of size S. Operand 0 is the resulting vector
|
|
in which 2*N elements of size N/2 are concatenated.
|
|
</p>
|
|
<a name="index-vec_005funpacks_005fhi_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005funpacks_005flo_005fm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>vec_unpacks_hi_<var>m</var></samp>’, ‘<samp>vec_unpacks_lo_<var>m</var></samp>’</dt>
|
|
<dd><p>Extract and widen (promote) the high/low part of a vector of signed
|
|
integral or floating point elements. The input vector (operand 1) has N
|
|
elements of size S. Widen (promote) the high/low elements of the vector
|
|
using signed or floating point extension and place the resulting N/2
|
|
values of size 2*S in the output vector (operand 0).
|
|
</p>
|
|
<a name="index-vec_005funpacku_005fhi_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005funpacku_005flo_005fm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>vec_unpacku_hi_<var>m</var></samp>’, ‘<samp>vec_unpacku_lo_<var>m</var></samp>’</dt>
|
|
<dd><p>Extract and widen (promote) the high/low part of a vector of unsigned
|
|
integral elements. The input vector (operand 1) has N elements of size S.
|
|
Widen (promote) the high/low elements of the vector using zero extension and
|
|
place the resulting N/2 values of size 2*S in the output vector (operand 0).
|
|
</p>
|
|
<a name="index-vec_005funpacks_005ffloat_005fhi_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005funpacks_005ffloat_005flo_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005funpacku_005ffloat_005fhi_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005funpacku_005ffloat_005flo_005fm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>vec_unpacks_float_hi_<var>m</var></samp>’, ‘<samp>vec_unpacks_float_lo_<var>m</var></samp>’</dt>
|
|
<dt>‘<samp>vec_unpacku_float_hi_<var>m</var></samp>’, ‘<samp>vec_unpacku_float_lo_<var>m</var></samp>’</dt>
|
|
<dd><p>Extract, convert to floating point type and widen the high/low part of a
|
|
vector of signed/unsigned integral elements. The input vector (operand 1)
|
|
has N elements of size S. Convert the high/low elements of the vector using
|
|
floating point conversion and place the resulting N/2 values of size 2*S in
|
|
the output vector (operand 0).
|
|
</p>
|
|
<a name="index-vec_005fwiden_005fumult_005fhi_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005fwiden_005fumult_005flo_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005fwiden_005fsmult_005fhi_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005fwiden_005fsmult_005flo_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005fwiden_005fumult_005feven_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005fwiden_005fumult_005fodd_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005fwiden_005fsmult_005feven_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005fwiden_005fsmult_005fodd_005fm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>vec_widen_umult_hi_<var>m</var></samp>’, ‘<samp>vec_widen_umult_lo_<var>m</var></samp>’</dt>
|
|
<dt>‘<samp>vec_widen_smult_hi_<var>m</var></samp>’, ‘<samp>vec_widen_smult_lo_<var>m</var></samp>’</dt>
|
|
<dt>‘<samp>vec_widen_umult_even_<var>m</var></samp>’, ‘<samp>vec_widen_umult_odd_<var>m</var></samp>’</dt>
|
|
<dt>‘<samp>vec_widen_smult_even_<var>m</var></samp>’, ‘<samp>vec_widen_smult_odd_<var>m</var></samp>’</dt>
|
|
<dd><p>Signed/Unsigned widening multiplication. The two inputs (operands 1 and 2)
|
|
are vectors with N signed/unsigned elements of size S. Multiply the high/low
|
|
or even/odd elements of the two vectors, and put the N/2 products of size 2*S
|
|
in the output vector (operand 0). A target shouldn’t implement even/odd pattern
|
|
pair if it is less efficient than lo/hi one.
|
|
</p>
|
|
<a name="index-vec_005fwiden_005fushiftl_005fhi_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005fwiden_005fushiftl_005flo_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005fwiden_005fsshiftl_005fhi_005fm-instruction-pattern"></a>
|
|
<a name="index-vec_005fwiden_005fsshiftl_005flo_005fm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>vec_widen_ushiftl_hi_<var>m</var></samp>’, ‘<samp>vec_widen_ushiftl_lo_<var>m</var></samp>’</dt>
|
|
<dt>‘<samp>vec_widen_sshiftl_hi_<var>m</var></samp>’, ‘<samp>vec_widen_sshiftl_lo_<var>m</var></samp>’</dt>
|
|
<dd><p>Signed/Unsigned widening shift left. The first input (operand 1) is a vector
|
|
with N signed/unsigned elements of size S. Operand 2 is a constant. Shift
|
|
the high/low elements of operand 1, and put the N/2 results of size 2*S in the
|
|
output vector (operand 0).
|
|
</p>
|
|
<a name="index-mulhisi3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>mulhisi3</samp>’</dt>
|
|
<dd><p>Multiply operands 1 and 2, which have mode <code>HImode</code>, and store
|
|
a <code>SImode</code> product in operand 0.
|
|
</p>
|
|
<a name="index-mulqihi3-instruction-pattern"></a>
|
|
<a name="index-mulsidi3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>mulqihi3</samp>’, ‘<samp>mulsidi3</samp>’</dt>
|
|
<dd><p>Similar widening-multiplication instructions of other widths.
|
|
</p>
|
|
<a name="index-umulqihi3-instruction-pattern"></a>
|
|
<a name="index-umulhisi3-instruction-pattern"></a>
|
|
<a name="index-umulsidi3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>umulqihi3</samp>’, ‘<samp>umulhisi3</samp>’, ‘<samp>umulsidi3</samp>’</dt>
|
|
<dd><p>Similar widening-multiplication instructions that do unsigned
|
|
multiplication.
|
|
</p>
|
|
<a name="index-usmulqihi3-instruction-pattern"></a>
|
|
<a name="index-usmulhisi3-instruction-pattern"></a>
|
|
<a name="index-usmulsidi3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>usmulqihi3</samp>’, ‘<samp>usmulhisi3</samp>’, ‘<samp>usmulsidi3</samp>’</dt>
|
|
<dd><p>Similar widening-multiplication instructions that interpret the first
|
|
operand as unsigned and the second operand as signed, then do a signed
|
|
multiplication.
|
|
</p>
|
|
<a name="index-smulm3_005fhighpart-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>smul<var>m</var>3_highpart</samp>’</dt>
|
|
<dd><p>Perform a signed multiplication of operands 1 and 2, which have mode
|
|
<var>m</var>, and store the most significant half of the product in operand 0.
|
|
The least significant half of the product is discarded.
|
|
</p>
|
|
<a name="index-umulm3_005fhighpart-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>umul<var>m</var>3_highpart</samp>’</dt>
|
|
<dd><p>Similar, but the multiplication is unsigned.
|
|
</p>
|
|
<a name="index-maddmn4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>madd<var>m</var><var>n</var>4</samp>’</dt>
|
|
<dd><p>Multiply operands 1 and 2, sign-extend them to mode <var>n</var>, add
|
|
operand 3, and store the result in operand 0. Operands 1 and 2
|
|
have mode <var>m</var> and operands 0 and 3 have mode <var>n</var>.
|
|
Both modes must be integer or fixed-point modes and <var>n</var> must be twice
|
|
the size of <var>m</var>.
|
|
</p>
|
|
<p>In other words, <code>madd<var>m</var><var>n</var>4</code> is like
|
|
<code>mul<var>m</var><var>n</var>3</code> except that it also adds operand 3.
|
|
</p>
|
|
<p>These instructions are not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-umaddmn4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>umadd<var>m</var><var>n</var>4</samp>’</dt>
|
|
<dd><p>Like <code>madd<var>m</var><var>n</var>4</code>, but zero-extend the multiplication
|
|
operands instead of sign-extending them.
|
|
</p>
|
|
<a name="index-ssmaddmn4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>ssmadd<var>m</var><var>n</var>4</samp>’</dt>
|
|
<dd><p>Like <code>madd<var>m</var><var>n</var>4</code>, but all involved operations must be
|
|
signed-saturating.
|
|
</p>
|
|
<a name="index-usmaddmn4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>usmadd<var>m</var><var>n</var>4</samp>’</dt>
|
|
<dd><p>Like <code>umadd<var>m</var><var>n</var>4</code>, but all involved operations must be
|
|
unsigned-saturating.
|
|
</p>
|
|
<a name="index-msubmn4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>msub<var>m</var><var>n</var>4</samp>’</dt>
|
|
<dd><p>Multiply operands 1 and 2, sign-extend them to mode <var>n</var>, subtract the
|
|
result from operand 3, and store the result in operand 0. Operands 1 and 2
|
|
have mode <var>m</var> and operands 0 and 3 have mode <var>n</var>.
|
|
Both modes must be integer or fixed-point modes and <var>n</var> must be twice
|
|
the size of <var>m</var>.
|
|
</p>
|
|
<p>In other words, <code>msub<var>m</var><var>n</var>4</code> is like
|
|
<code>mul<var>m</var><var>n</var>3</code> except that it also subtracts the result
|
|
from operand 3.
|
|
</p>
|
|
<p>These instructions are not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-umsubmn4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>umsub<var>m</var><var>n</var>4</samp>’</dt>
|
|
<dd><p>Like <code>msub<var>m</var><var>n</var>4</code>, but zero-extend the multiplication
|
|
operands instead of sign-extending them.
|
|
</p>
|
|
<a name="index-ssmsubmn4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>ssmsub<var>m</var><var>n</var>4</samp>’</dt>
|
|
<dd><p>Like <code>msub<var>m</var><var>n</var>4</code>, but all involved operations must be
|
|
signed-saturating.
|
|
</p>
|
|
<a name="index-usmsubmn4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>usmsub<var>m</var><var>n</var>4</samp>’</dt>
|
|
<dd><p>Like <code>umsub<var>m</var><var>n</var>4</code>, but all involved operations must be
|
|
unsigned-saturating.
|
|
</p>
|
|
<a name="index-divmodm4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>divmod<var>m</var>4</samp>’</dt>
|
|
<dd><p>Signed division that produces both a quotient and a remainder.
|
|
Operand 1 is divided by operand 2 to produce a quotient stored
|
|
in operand 0 and a remainder stored in operand 3.
|
|
</p>
|
|
<p>For machines with an instruction that produces both a quotient and a
|
|
remainder, provide a pattern for ‘<samp>divmod<var>m</var>4</samp>’ but do not
|
|
provide patterns for ‘<samp>div<var>m</var>3</samp>’ and ‘<samp>mod<var>m</var>3</samp>’. This
|
|
allows optimization in the relatively common case when both the quotient
|
|
and remainder are computed.
|
|
</p>
|
|
<p>If an instruction that just produces a quotient or just a remainder
|
|
exists and is more efficient than the instruction that produces both,
|
|
write the output routine of ‘<samp>divmod<var>m</var>4</samp>’ to call
|
|
<code>find_reg_note</code> and look for a <code>REG_UNUSED</code> note on the
|
|
quotient or remainder and generate the appropriate instruction.
|
|
</p>
|
|
<a name="index-udivmodm4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>udivmod<var>m</var>4</samp>’</dt>
|
|
<dd><p>Similar, but does unsigned division.
|
|
</p>
|
|
<a name="shift-patterns"></a><a name="index-ashlm3-instruction-pattern"></a>
|
|
<a name="index-ssashlm3-instruction-pattern"></a>
|
|
<a name="index-usashlm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>ashl<var>m</var>3</samp>’, ‘<samp>ssashl<var>m</var>3</samp>’, ‘<samp>usashl<var>m</var>3</samp>’</dt>
|
|
<dd><p>Arithmetic-shift operand 1 left by a number of bits specified by operand
|
|
2, and store the result in operand 0. Here <var>m</var> is the mode of
|
|
operand 0 and operand 1; operand 2’s mode is specified by the
|
|
instruction pattern, and the compiler will convert the operand to that
|
|
mode before generating the instruction. The shift or rotate expander
|
|
or instruction pattern should explicitly specify the mode of the operand 2,
|
|
it should never be <code>VOIDmode</code>. The meaning of out-of-range shift
|
|
counts can optionally be specified by <code>TARGET_SHIFT_TRUNCATION_MASK</code>.
|
|
See <a href="Misc.html#TARGET_005fSHIFT_005fTRUNCATION_005fMASK">TARGET_SHIFT_TRUNCATION_MASK</a>. Operand 2 is always a scalar type.
|
|
</p>
|
|
<a name="index-ashrm3-instruction-pattern"></a>
|
|
<a name="index-lshrm3-instruction-pattern"></a>
|
|
<a name="index-rotlm3-instruction-pattern"></a>
|
|
<a name="index-rotrm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>ashr<var>m</var>3</samp>’, ‘<samp>lshr<var>m</var>3</samp>’, ‘<samp>rotl<var>m</var>3</samp>’, ‘<samp>rotr<var>m</var>3</samp>’</dt>
|
|
<dd><p>Other shift and rotate instructions, analogous to the
|
|
<code>ashl<var>m</var>3</code> instructions. Operand 2 is always a scalar type.
|
|
</p>
|
|
<a name="index-vashlm3-instruction-pattern"></a>
|
|
<a name="index-vashrm3-instruction-pattern"></a>
|
|
<a name="index-vlshrm3-instruction-pattern"></a>
|
|
<a name="index-vrotlm3-instruction-pattern"></a>
|
|
<a name="index-vrotrm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>vashl<var>m</var>3</samp>’, ‘<samp>vashr<var>m</var>3</samp>’, ‘<samp>vlshr<var>m</var>3</samp>’, ‘<samp>vrotl<var>m</var>3</samp>’, ‘<samp>vrotr<var>m</var>3</samp>’</dt>
|
|
<dd><p>Vector shift and rotate instructions that take vectors as operand 2
|
|
instead of a scalar type.
|
|
</p>
|
|
<a name="index-bswapm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>bswap<var>m</var>2</samp>’</dt>
|
|
<dd><p>Reverse the order of bytes of operand 1 and store the result in operand 0.
|
|
</p>
|
|
<a name="index-negm2-instruction-pattern"></a>
|
|
<a name="index-ssnegm2-instruction-pattern"></a>
|
|
<a name="index-usnegm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>neg<var>m</var>2</samp>’, ‘<samp>ssneg<var>m</var>2</samp>’, ‘<samp>usneg<var>m</var>2</samp>’</dt>
|
|
<dd><p>Negate operand 1 and store the result in operand 0.
|
|
</p>
|
|
<a name="index-negvm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>negv<var>m</var>3</samp>’</dt>
|
|
<dd><p>Like <code>neg<var>m</var>2</code> but takes a <code>code_label</code> as operand 2 and
|
|
emits code to jump to it if signed overflow occurs during the negation.
|
|
</p>
|
|
<a name="index-absm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>abs<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the absolute value of operand 1 into operand 0.
|
|
</p>
|
|
<a name="index-sqrtm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>sqrt<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the square root of operand 1 into operand 0. Both operands have
|
|
mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-rsqrtm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>rsqrt<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the reciprocal of the square root of operand 1 into operand 0.
|
|
Both operands have mode <var>m</var>, which is a scalar or vector
|
|
floating-point mode.
|
|
</p>
|
|
<p>On most architectures this pattern is only approximate, so either
|
|
its C condition or the <code>TARGET_OPTAB_SUPPORTED_P</code> hook should
|
|
check for the appropriate math flags. (Using the C condition is
|
|
more direct, but using <code>TARGET_OPTAB_SUPPORTED_P</code> can be useful
|
|
if a target-specific built-in also uses the ‘<samp>rsqrt<var>m</var>2</samp>’
|
|
pattern.)
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-fmodm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>fmod<var>m</var>3</samp>’</dt>
|
|
<dd><p>Store the remainder of dividing operand 1 by operand 2 into
|
|
operand 0, rounded towards zero to an integer. All operands have
|
|
mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-remainderm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>remainder<var>m</var>3</samp>’</dt>
|
|
<dd><p>Store the remainder of dividing operand 1 by operand 2 into
|
|
operand 0, rounded to the nearest integer. All operands have
|
|
mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-scalbm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>scalb<var>m</var>3</samp>’</dt>
|
|
<dd><p>Raise <code>FLT_RADIX</code> to the power of operand 2, multiply it by
|
|
operand 1, and store the result in operand 0. All operands have
|
|
mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-ldexpm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>ldexp<var>m</var>3</samp>’</dt>
|
|
<dd><p>Raise 2 to the power of operand 2, multiply it by operand 1, and store
|
|
the result in operand 0. Operands 0 and 1 have mode <var>m</var>, which is
|
|
a scalar or vector floating-point mode. Operand 2’s mode has
|
|
the same number of elements as <var>m</var> and each element is wide
|
|
enough to store an <code>int</code>. The integers are signed.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-cosm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>cos<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the cosine of operand 1 into operand 0. Both operands have
|
|
mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-sinm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>sin<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the sine of operand 1 into operand 0. Both operands have
|
|
mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-sincosm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>sincos<var>m</var>3</samp>’</dt>
|
|
<dd><p>Store the cosine of operand 2 into operand 0 and the sine of
|
|
operand 2 into operand 1. All operands have mode <var>m</var>,
|
|
which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>Targets that can calculate the sine and cosine simultaneously can
|
|
implement this pattern as opposed to implementing individual
|
|
<code>sin<var>m</var>2</code> and <code>cos<var>m</var>2</code> patterns. The <code>sin</code>
|
|
and <code>cos</code> built-in functions will then be expanded to the
|
|
<code>sincos<var>m</var>3</code> pattern, with one of the output values
|
|
left unused.
|
|
</p>
|
|
<a name="index-tanm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>tan<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the tangent of operand 1 into operand 0. Both operands have
|
|
mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-asinm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>asin<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the arc sine of operand 1 into operand 0. Both operands have
|
|
mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-acosm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>acos<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the arc cosine of operand 1 into operand 0. Both operands have
|
|
mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-atanm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>atan<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the arc tangent of operand 1 into operand 0. Both operands have
|
|
mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-expm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>exp<var>m</var>2</samp>’</dt>
|
|
<dd><p>Raise e (the base of natural logarithms) to the power of operand 1
|
|
and store the result in operand 0. Both operands have mode <var>m</var>,
|
|
which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-expm1m2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>expm1<var>m</var>2</samp>’</dt>
|
|
<dd><p>Raise e (the base of natural logarithms) to the power of operand 1,
|
|
subtract 1, and store the result in operand 0. Both operands have
|
|
mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>For inputs close to zero, the pattern is expected to be more
|
|
accurate than a separate <code>exp<var>m</var>2</code> and <code>sub<var>m</var>3</code>
|
|
would be.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-exp10m2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>exp10<var>m</var>2</samp>’</dt>
|
|
<dd><p>Raise 10 to the power of operand 1 and store the result in operand 0.
|
|
Both operands have mode <var>m</var>, which is a scalar or vector
|
|
floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-exp2m2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>exp2<var>m</var>2</samp>’</dt>
|
|
<dd><p>Raise 2 to the power of operand 1 and store the result in operand 0.
|
|
Both operands have mode <var>m</var>, which is a scalar or vector
|
|
floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-logm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>log<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the natural logarithm of operand 1 into operand 0. Both operands
|
|
have mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-log1pm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>log1p<var>m</var>2</samp>’</dt>
|
|
<dd><p>Add 1 to operand 1, compute the natural logarithm, and store
|
|
the result in operand 0. Both operands have mode <var>m</var>, which is
|
|
a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>For inputs close to zero, the pattern is expected to be more
|
|
accurate than a separate <code>add<var>m</var>3</code> and <code>log<var>m</var>2</code>
|
|
would be.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-log10m2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>log10<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the base-10 logarithm of operand 1 into operand 0. Both operands
|
|
have mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-log2m2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>log2<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the base-2 logarithm of operand 1 into operand 0. Both operands
|
|
have mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-logbm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>logb<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the base-<code>FLT_RADIX</code> logarithm of operand 1 into operand 0.
|
|
Both operands have mode <var>m</var>, which is a scalar or vector
|
|
floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-significandm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>significand<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the significand of floating-point operand 1 in operand 0.
|
|
Both operands have mode <var>m</var>, which is a scalar or vector
|
|
floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-powm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>pow<var>m</var>3</samp>’</dt>
|
|
<dd><p>Store the value of operand 1 raised to the exponent operand 2
|
|
into operand 0. All operands have mode <var>m</var>, which is a scalar
|
|
or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-atan2m3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>atan2<var>m</var>3</samp>’</dt>
|
|
<dd><p>Store the arc tangent (inverse tangent) of operand 1 divided by
|
|
operand 2 into operand 0, using the signs of both arguments to
|
|
determine the quadrant of the result. All operands have mode
|
|
<var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-floorm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>floor<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the largest integral value not greater than operand 1 in operand 0.
|
|
Both operands have mode <var>m</var>, which is a scalar or vector
|
|
floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-btruncm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>btrunc<var>m</var>2</samp>’</dt>
|
|
<dd><p>Round operand 1 to an integer, towards zero, and store the result in
|
|
operand 0. Both operands have mode <var>m</var>, which is a scalar or
|
|
vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-roundm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>round<var>m</var>2</samp>’</dt>
|
|
<dd><p>Round operand 1 to the nearest integer, rounding away from zero in the
|
|
event of a tie, and store the result in operand 0. Both operands have
|
|
mode <var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-ceilm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>ceil<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the smallest integral value not less than operand 1 in operand 0.
|
|
Both operands have mode <var>m</var>, which is a scalar or vector
|
|
floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-nearbyintm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>nearbyint<var>m</var>2</samp>’</dt>
|
|
<dd><p>Round operand 1 to an integer, using the current rounding mode, and
|
|
store the result in operand 0. Do not raise an inexact condition when
|
|
the result is different from the argument. Both operands have mode
|
|
<var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-rintm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>rint<var>m</var>2</samp>’</dt>
|
|
<dd><p>Round operand 1 to an integer, using the current rounding mode, and
|
|
store the result in operand 0. Raise an inexact condition when
|
|
the result is different from the argument. Both operands have mode
|
|
<var>m</var>, which is a scalar or vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-lrintmn2"></a>
|
|
</dd>
|
|
<dt>‘<samp>lrint<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Convert operand 1 (valid for floating point mode <var>m</var>) to fixed
|
|
point mode <var>n</var> as a signed number according to the current
|
|
rounding mode and store in operand 0 (which has mode <var>n</var>).
|
|
</p>
|
|
<a name="index-lroundmn2"></a>
|
|
</dd>
|
|
<dt>‘<samp>lround<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Convert operand 1 (valid for floating point mode <var>m</var>) to fixed
|
|
point mode <var>n</var> as a signed number rounding to nearest and away
|
|
from zero and store in operand 0 (which has mode <var>n</var>).
|
|
</p>
|
|
<a name="index-lfloormn2"></a>
|
|
</dd>
|
|
<dt>‘<samp>lfloor<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Convert operand 1 (valid for floating point mode <var>m</var>) to fixed
|
|
point mode <var>n</var> as a signed number rounding down and store in
|
|
operand 0 (which has mode <var>n</var>).
|
|
</p>
|
|
<a name="index-lceilmn2"></a>
|
|
</dd>
|
|
<dt>‘<samp>lceil<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Convert operand 1 (valid for floating point mode <var>m</var>) to fixed
|
|
point mode <var>n</var> as a signed number rounding up and store in
|
|
operand 0 (which has mode <var>n</var>).
|
|
</p>
|
|
<a name="index-copysignm3-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>copysign<var>m</var>3</samp>’</dt>
|
|
<dd><p>Store a value with the magnitude of operand 1 and the sign of operand
|
|
2 into operand 0. All operands have mode <var>m</var>, which is a scalar or
|
|
vector floating-point mode.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-ffsm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>ffs<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store into operand 0 one plus the index of the least significant 1-bit
|
|
of operand 1. If operand 1 is zero, store zero.
|
|
</p>
|
|
<p><var>m</var> is either a scalar or vector integer mode. When it is a scalar,
|
|
operand 1 has mode <var>m</var> but operand 0 can have whatever scalar
|
|
integer mode is suitable for the target. The compiler will insert
|
|
conversion instructions as necessary (typically to convert the result
|
|
to the same width as <code>int</code>). When <var>m</var> is a vector, both
|
|
operands must have mode <var>m</var>.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-clrsbm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>clrsb<var>m</var>2</samp>’</dt>
|
|
<dd><p>Count leading redundant sign bits.
|
|
Store into operand 0 the number of redundant sign bits in operand 1, starting
|
|
at the most significant bit position.
|
|
A redundant sign bit is defined as any sign bit after the first. As such,
|
|
this count will be one less than the count of leading sign bits.
|
|
</p>
|
|
<p><var>m</var> is either a scalar or vector integer mode. When it is a scalar,
|
|
operand 1 has mode <var>m</var> but operand 0 can have whatever scalar
|
|
integer mode is suitable for the target. The compiler will insert
|
|
conversion instructions as necessary (typically to convert the result
|
|
to the same width as <code>int</code>). When <var>m</var> is a vector, both
|
|
operands must have mode <var>m</var>.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-clzm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>clz<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store into operand 0 the number of leading 0-bits in operand 1, starting
|
|
at the most significant bit position. If operand 1 is 0, the
|
|
<code>CLZ_DEFINED_VALUE_AT_ZERO</code> (see <a href="Misc.html#Misc">Misc</a>) macro defines if
|
|
the result is undefined or has a useful value.
|
|
</p>
|
|
<p><var>m</var> is either a scalar or vector integer mode. When it is a scalar,
|
|
operand 1 has mode <var>m</var> but operand 0 can have whatever scalar
|
|
integer mode is suitable for the target. The compiler will insert
|
|
conversion instructions as necessary (typically to convert the result
|
|
to the same width as <code>int</code>). When <var>m</var> is a vector, both
|
|
operands must have mode <var>m</var>.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-ctzm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>ctz<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store into operand 0 the number of trailing 0-bits in operand 1, starting
|
|
at the least significant bit position. If operand 1 is 0, the
|
|
<code>CTZ_DEFINED_VALUE_AT_ZERO</code> (see <a href="Misc.html#Misc">Misc</a>) macro defines if
|
|
the result is undefined or has a useful value.
|
|
</p>
|
|
<p><var>m</var> is either a scalar or vector integer mode. When it is a scalar,
|
|
operand 1 has mode <var>m</var> but operand 0 can have whatever scalar
|
|
integer mode is suitable for the target. The compiler will insert
|
|
conversion instructions as necessary (typically to convert the result
|
|
to the same width as <code>int</code>). When <var>m</var> is a vector, both
|
|
operands must have mode <var>m</var>.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-popcountm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>popcount<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store into operand 0 the number of 1-bits in operand 1.
|
|
</p>
|
|
<p><var>m</var> is either a scalar or vector integer mode. When it is a scalar,
|
|
operand 1 has mode <var>m</var> but operand 0 can have whatever scalar
|
|
integer mode is suitable for the target. The compiler will insert
|
|
conversion instructions as necessary (typically to convert the result
|
|
to the same width as <code>int</code>). When <var>m</var> is a vector, both
|
|
operands must have mode <var>m</var>.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-paritym2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>parity<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store into operand 0 the parity of operand 1, i.e. the number of 1-bits
|
|
in operand 1 modulo 2.
|
|
</p>
|
|
<p><var>m</var> is either a scalar or vector integer mode. When it is a scalar,
|
|
operand 1 has mode <var>m</var> but operand 0 can have whatever scalar
|
|
integer mode is suitable for the target. The compiler will insert
|
|
conversion instructions as necessary (typically to convert the result
|
|
to the same width as <code>int</code>). When <var>m</var> is a vector, both
|
|
operands must have mode <var>m</var>.
|
|
</p>
|
|
<p>This pattern is not allowed to <code>FAIL</code>.
|
|
</p>
|
|
<a name="index-one_005fcmplm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>one_cmpl<var>m</var>2</samp>’</dt>
|
|
<dd><p>Store the bitwise-complement of operand 1 into operand 0.
|
|
</p>
|
|
<a name="index-movmemm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>movmem<var>m</var></samp>’</dt>
|
|
<dd><p>Block move instruction. The destination and source blocks of memory
|
|
are the first two operands, and both are <code>mem:BLK</code>s with an
|
|
address in mode <code>Pmode</code>.
|
|
</p>
|
|
<p>The number of bytes to move is the third operand, in mode <var>m</var>.
|
|
Usually, you specify <code>Pmode</code> for <var>m</var>. However, if you can
|
|
generate better code knowing the range of valid lengths is smaller than
|
|
those representable in a full Pmode pointer, you should provide
|
|
a pattern with a
|
|
mode corresponding to the range of values you can handle efficiently
|
|
(e.g., <code>QImode</code> for values in the range 0–127; note we avoid numbers
|
|
that appear negative) and also a pattern with <code>Pmode</code>.
|
|
</p>
|
|
<p>The fourth operand is the known shared alignment of the source and
|
|
destination, in the form of a <code>const_int</code> rtx. Thus, if the
|
|
compiler knows that both source and destination are word-aligned,
|
|
it may provide the value 4 for this operand.
|
|
</p>
|
|
<p>Optional operands 5 and 6 specify expected alignment and size of block
|
|
respectively. The expected alignment differs from alignment in operand 4
|
|
in a way that the blocks are not required to be aligned according to it in
|
|
all cases. This expected alignment is also in bytes, just like operand 4.
|
|
Expected size, when unknown, is set to <code>(const_int -1)</code>.
|
|
</p>
|
|
<p>Descriptions of multiple <code>movmem<var>m</var></code> patterns can only be
|
|
beneficial if the patterns for smaller modes have fewer restrictions
|
|
on their first, second and fourth operands. Note that the mode <var>m</var>
|
|
in <code>movmem<var>m</var></code> does not impose any restriction on the mode of
|
|
individually moved data units in the block.
|
|
</p>
|
|
<p>These patterns need not give special consideration to the possibility
|
|
that the source and destination strings might overlap.
|
|
</p>
|
|
<a name="index-movstr-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>movstr</samp>’</dt>
|
|
<dd><p>String copy instruction, with <code>stpcpy</code> semantics. Operand 0 is
|
|
an output operand in mode <code>Pmode</code>. The addresses of the
|
|
destination and source strings are operands 1 and 2, and both are
|
|
<code>mem:BLK</code>s with addresses in mode <code>Pmode</code>. The execution of
|
|
the expansion of this pattern should store in operand 0 the address in
|
|
which the <code>NUL</code> terminator was stored in the destination string.
|
|
</p>
|
|
<p>This patern has also several optional operands that are same as in
|
|
<code>setmem</code>.
|
|
</p>
|
|
<a name="index-setmemm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>setmem<var>m</var></samp>’</dt>
|
|
<dd><p>Block set instruction. The destination string is the first operand,
|
|
given as a <code>mem:BLK</code> whose address is in mode <code>Pmode</code>. The
|
|
number of bytes to set is the second operand, in mode <var>m</var>. The value to
|
|
initialize the memory with is the third operand. Targets that only support the
|
|
clearing of memory should reject any value that is not the constant 0. See
|
|
‘<samp>movmem<var>m</var></samp>’ for a discussion of the choice of mode.
|
|
</p>
|
|
<p>The fourth operand is the known alignment of the destination, in the form
|
|
of a <code>const_int</code> rtx. Thus, if the compiler knows that the
|
|
destination is word-aligned, it may provide the value 4 for this
|
|
operand.
|
|
</p>
|
|
<p>Optional operands 5 and 6 specify expected alignment and size of block
|
|
respectively. The expected alignment differs from alignment in operand 4
|
|
in a way that the blocks are not required to be aligned according to it in
|
|
all cases. This expected alignment is also in bytes, just like operand 4.
|
|
Expected size, when unknown, is set to <code>(const_int -1)</code>.
|
|
Operand 7 is the minimal size of the block and operand 8 is the
|
|
maximal size of the block (NULL if it can not be represented as CONST_INT).
|
|
Operand 9 is the probable maximal size (i.e. we can not rely on it for correctness,
|
|
but it can be used for choosing proper code sequence for a given size).
|
|
</p>
|
|
<p>The use for multiple <code>setmem<var>m</var></code> is as for <code>movmem<var>m</var></code>.
|
|
</p>
|
|
<a name="index-cmpstrnm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>cmpstrn<var>m</var></samp>’</dt>
|
|
<dd><p>String compare instruction, with five operands. Operand 0 is the output;
|
|
it has mode <var>m</var>. The remaining four operands are like the operands
|
|
of ‘<samp>movmem<var>m</var></samp>’. The two memory blocks specified are compared
|
|
byte by byte in lexicographic order starting at the beginning of each
|
|
string. The instruction is not allowed to prefetch more than one byte
|
|
at a time since either string may end in the first byte and reading past
|
|
that may access an invalid page or segment and cause a fault. The
|
|
comparison terminates early if the fetched bytes are different or if
|
|
they are equal to zero. The effect of the instruction is to store a
|
|
value in operand 0 whose sign indicates the result of the comparison.
|
|
</p>
|
|
<a name="index-cmpstrm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>cmpstr<var>m</var></samp>’</dt>
|
|
<dd><p>String compare instruction, without known maximum length. Operand 0 is the
|
|
output; it has mode <var>m</var>. The second and third operand are the blocks of
|
|
memory to be compared; both are <code>mem:BLK</code> with an address in mode
|
|
<code>Pmode</code>.
|
|
</p>
|
|
<p>The fourth operand is the known shared alignment of the source and
|
|
destination, in the form of a <code>const_int</code> rtx. Thus, if the
|
|
compiler knows that both source and destination are word-aligned,
|
|
it may provide the value 4 for this operand.
|
|
</p>
|
|
<p>The two memory blocks specified are compared byte by byte in lexicographic
|
|
order starting at the beginning of each string. The instruction is not allowed
|
|
to prefetch more than one byte at a time since either string may end in the
|
|
first byte and reading past that may access an invalid page or segment and
|
|
cause a fault. The comparison will terminate when the fetched bytes
|
|
are different or if they are equal to zero. The effect of the
|
|
instruction is to store a value in operand 0 whose sign indicates the
|
|
result of the comparison.
|
|
</p>
|
|
<a name="index-cmpmemm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>cmpmem<var>m</var></samp>’</dt>
|
|
<dd><p>Block compare instruction, with five operands like the operands
|
|
of ‘<samp>cmpstr<var>m</var></samp>’. The two memory blocks specified are compared
|
|
byte by byte in lexicographic order starting at the beginning of each
|
|
block. Unlike ‘<samp>cmpstr<var>m</var></samp>’ the instruction can prefetch
|
|
any bytes in the two memory blocks. Also unlike ‘<samp>cmpstr<var>m</var></samp>’
|
|
the comparison will not stop if both bytes are zero. The effect of
|
|
the instruction is to store a value in operand 0 whose sign indicates
|
|
the result of the comparison.
|
|
</p>
|
|
<a name="index-strlenm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>strlen<var>m</var></samp>’</dt>
|
|
<dd><p>Compute the length of a string, with three operands.
|
|
Operand 0 is the result (of mode <var>m</var>), operand 1 is
|
|
a <code>mem</code> referring to the first character of the string,
|
|
operand 2 is the character to search for (normally zero),
|
|
and operand 3 is a constant describing the known alignment
|
|
of the beginning of the string.
|
|
</p>
|
|
<a name="index-floatmn2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>float<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Convert signed integer operand 1 (valid for fixed point mode <var>m</var>) to
|
|
floating point mode <var>n</var> and store in operand 0 (which has mode
|
|
<var>n</var>).
|
|
</p>
|
|
<a name="index-floatunsmn2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>floatuns<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Convert unsigned integer operand 1 (valid for fixed point mode <var>m</var>)
|
|
to floating point mode <var>n</var> and store in operand 0 (which has mode
|
|
<var>n</var>).
|
|
</p>
|
|
<a name="index-fixmn2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>fix<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Convert operand 1 (valid for floating point mode <var>m</var>) to fixed
|
|
point mode <var>n</var> as a signed number and store in operand 0 (which
|
|
has mode <var>n</var>). This instruction’s result is defined only when
|
|
the value of operand 1 is an integer.
|
|
</p>
|
|
<p>If the machine description defines this pattern, it also needs to
|
|
define the <code>ftrunc</code> pattern.
|
|
</p>
|
|
<a name="index-fixunsmn2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>fixuns<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Convert operand 1 (valid for floating point mode <var>m</var>) to fixed
|
|
point mode <var>n</var> as an unsigned number and store in operand 0 (which
|
|
has mode <var>n</var>). This instruction’s result is defined only when the
|
|
value of operand 1 is an integer.
|
|
</p>
|
|
<a name="index-ftruncm2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>ftrunc<var>m</var>2</samp>’</dt>
|
|
<dd><p>Convert operand 1 (valid for floating point mode <var>m</var>) to an
|
|
integer value, still represented in floating point mode <var>m</var>, and
|
|
store it in operand 0 (valid for floating point mode <var>m</var>).
|
|
</p>
|
|
<a name="index-fix_005ftruncmn2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>fix_trunc<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Like ‘<samp>fix<var>m</var><var>n</var>2</samp>’ but works for any floating point value
|
|
of mode <var>m</var> by converting the value to an integer.
|
|
</p>
|
|
<a name="index-fixuns_005ftruncmn2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>fixuns_trunc<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Like ‘<samp>fixuns<var>m</var><var>n</var>2</samp>’ but works for any floating point
|
|
value of mode <var>m</var> by converting the value to an integer.
|
|
</p>
|
|
<a name="index-truncmn2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>trunc<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Truncate operand 1 (valid for mode <var>m</var>) to mode <var>n</var> and
|
|
store in operand 0 (which has mode <var>n</var>). Both modes must be fixed
|
|
point or both floating point.
|
|
</p>
|
|
<a name="index-extendmn2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>extend<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Sign-extend operand 1 (valid for mode <var>m</var>) to mode <var>n</var> and
|
|
store in operand 0 (which has mode <var>n</var>). Both modes must be fixed
|
|
point or both floating point.
|
|
</p>
|
|
<a name="index-zero_005fextendmn2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>zero_extend<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Zero-extend operand 1 (valid for mode <var>m</var>) to mode <var>n</var> and
|
|
store in operand 0 (which has mode <var>n</var>). Both modes must be fixed
|
|
point.
|
|
</p>
|
|
<a name="index-fractmn2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>fract<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Convert operand 1 of mode <var>m</var> to mode <var>n</var> and store in
|
|
operand 0 (which has mode <var>n</var>). Mode <var>m</var> and mode <var>n</var>
|
|
could be fixed-point to fixed-point, signed integer to fixed-point,
|
|
fixed-point to signed integer, floating-point to fixed-point,
|
|
or fixed-point to floating-point.
|
|
When overflows or underflows happen, the results are undefined.
|
|
</p>
|
|
<a name="index-satfractmn2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>satfract<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Convert operand 1 of mode <var>m</var> to mode <var>n</var> and store in
|
|
operand 0 (which has mode <var>n</var>). Mode <var>m</var> and mode <var>n</var>
|
|
could be fixed-point to fixed-point, signed integer to fixed-point,
|
|
or floating-point to fixed-point.
|
|
When overflows or underflows happen, the instruction saturates the
|
|
results to the maximum or the minimum.
|
|
</p>
|
|
<a name="index-fractunsmn2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>fractuns<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Convert operand 1 of mode <var>m</var> to mode <var>n</var> and store in
|
|
operand 0 (which has mode <var>n</var>). Mode <var>m</var> and mode <var>n</var>
|
|
could be unsigned integer to fixed-point, or
|
|
fixed-point to unsigned integer.
|
|
When overflows or underflows happen, the results are undefined.
|
|
</p>
|
|
<a name="index-satfractunsmn2-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>satfractuns<var>m</var><var>n</var>2</samp>’</dt>
|
|
<dd><p>Convert unsigned integer operand 1 of mode <var>m</var> to fixed-point mode
|
|
<var>n</var> and store in operand 0 (which has mode <var>n</var>).
|
|
When overflows or underflows happen, the instruction saturates the
|
|
results to the maximum or the minimum.
|
|
</p>
|
|
<a name="index-extvm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>extv<var>m</var></samp>’</dt>
|
|
<dd><p>Extract a bit-field from register operand 1, sign-extend it, and store
|
|
it in operand 0. Operand 2 specifies the width of the field in bits
|
|
and operand 3 the starting bit, which counts from the most significant
|
|
bit if ‘<samp>BITS_BIG_ENDIAN</samp>’ is true and from the least significant bit
|
|
otherwise.
|
|
</p>
|
|
<p>Operands 0 and 1 both have mode <var>m</var>. Operands 2 and 3 have a
|
|
target-specific mode.
|
|
</p>
|
|
<a name="index-extvmisalignm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>extvmisalign<var>m</var></samp>’</dt>
|
|
<dd><p>Extract a bit-field from memory operand 1, sign extend it, and store
|
|
it in operand 0. Operand 2 specifies the width in bits and operand 3
|
|
the starting bit. The starting bit is always somewhere in the first byte of
|
|
operand 1; it counts from the most significant bit if ‘<samp>BITS_BIG_ENDIAN</samp>’
|
|
is true and from the least significant bit otherwise.
|
|
</p>
|
|
<p>Operand 0 has mode <var>m</var> while operand 1 has <code>BLK</code> mode.
|
|
Operands 2 and 3 have a target-specific mode.
|
|
</p>
|
|
<p>The instruction must not read beyond the last byte of the bit-field.
|
|
</p>
|
|
<a name="index-extzvm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>extzv<var>m</var></samp>’</dt>
|
|
<dd><p>Like ‘<samp>extv<var>m</var></samp>’ except that the bit-field value is zero-extended.
|
|
</p>
|
|
<a name="index-extzvmisalignm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>extzvmisalign<var>m</var></samp>’</dt>
|
|
<dd><p>Like ‘<samp>extvmisalign<var>m</var></samp>’ except that the bit-field value is
|
|
zero-extended.
|
|
</p>
|
|
<a name="index-insvm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>insv<var>m</var></samp>’</dt>
|
|
<dd><p>Insert operand 3 into a bit-field of register operand 0. Operand 1
|
|
specifies the width of the field in bits and operand 2 the starting bit,
|
|
which counts from the most significant bit if ‘<samp>BITS_BIG_ENDIAN</samp>’
|
|
is true and from the least significant bit otherwise.
|
|
</p>
|
|
<p>Operands 0 and 3 both have mode <var>m</var>. Operands 1 and 2 have a
|
|
target-specific mode.
|
|
</p>
|
|
<a name="index-insvmisalignm-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>insvmisalign<var>m</var></samp>’</dt>
|
|
<dd><p>Insert operand 3 into a bit-field of memory operand 0. Operand 1
|
|
specifies the width of the field in bits and operand 2 the starting bit.
|
|
The starting bit is always somewhere in the first byte of operand 0;
|
|
it counts from the most significant bit if ‘<samp>BITS_BIG_ENDIAN</samp>’
|
|
is true and from the least significant bit otherwise.
|
|
</p>
|
|
<p>Operand 3 has mode <var>m</var> while operand 0 has <code>BLK</code> mode.
|
|
Operands 1 and 2 have a target-specific mode.
|
|
</p>
|
|
<p>The instruction must not read or write beyond the last byte of the bit-field.
|
|
</p>
|
|
<a name="index-extv-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>extv</samp>’</dt>
|
|
<dd><p>Extract a bit-field from operand 1 (a register or memory operand), where
|
|
operand 2 specifies the width in bits and operand 3 the starting bit,
|
|
and store it in operand 0. Operand 0 must have mode <code>word_mode</code>.
|
|
Operand 1 may have mode <code>byte_mode</code> or <code>word_mode</code>; often
|
|
<code>word_mode</code> is allowed only for registers. Operands 2 and 3 must
|
|
be valid for <code>word_mode</code>.
|
|
</p>
|
|
<p>The RTL generation pass generates this instruction only with constants
|
|
for operands 2 and 3 and the constant is never zero for operand 2.
|
|
</p>
|
|
<p>The bit-field value is sign-extended to a full word integer
|
|
before it is stored in operand 0.
|
|
</p>
|
|
<p>This pattern is deprecated; please use ‘<samp>extv<var>m</var></samp>’ and
|
|
<code>extvmisalign<var>m</var></code> instead.
|
|
</p>
|
|
<a name="index-extzv-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>extzv</samp>’</dt>
|
|
<dd><p>Like ‘<samp>extv</samp>’ except that the bit-field value is zero-extended.
|
|
</p>
|
|
<p>This pattern is deprecated; please use ‘<samp>extzv<var>m</var></samp>’ and
|
|
<code>extzvmisalign<var>m</var></code> instead.
|
|
</p>
|
|
<a name="index-insv-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>insv</samp>’</dt>
|
|
<dd><p>Store operand 3 (which must be valid for <code>word_mode</code>) into a
|
|
bit-field in operand 0, where operand 1 specifies the width in bits and
|
|
operand 2 the starting bit. Operand 0 may have mode <code>byte_mode</code> or
|
|
<code>word_mode</code>; often <code>word_mode</code> is allowed only for registers.
|
|
Operands 1 and 2 must be valid for <code>word_mode</code>.
|
|
</p>
|
|
<p>The RTL generation pass generates this instruction only with constants
|
|
for operands 1 and 2 and the constant is never zero for operand 1.
|
|
</p>
|
|
<p>This pattern is deprecated; please use ‘<samp>insv<var>m</var></samp>’ and
|
|
<code>insvmisalign<var>m</var></code> instead.
|
|
</p>
|
|
<a name="index-movmodecc-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>mov<var>mode</var>cc</samp>’</dt>
|
|
<dd><p>Conditionally move operand 2 or operand 3 into operand 0 according to the
|
|
comparison in operand 1. If the comparison is true, operand 2 is moved
|
|
into operand 0, otherwise operand 3 is moved.
|
|
</p>
|
|
<p>The mode of the operands being compared need not be the same as the operands
|
|
being moved. Some machines, sparc64 for example, have instructions that
|
|
conditionally move an integer value based on the floating point condition
|
|
codes and vice versa.
|
|
</p>
|
|
<p>If the machine does not have conditional move instructions, do not
|
|
define these patterns.
|
|
</p>
|
|
<a name="index-addmodecc-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>add<var>mode</var>cc</samp>’</dt>
|
|
<dd><p>Similar to ‘<samp>mov<var>mode</var>cc</samp>’ but for conditional addition. Conditionally
|
|
move operand 2 or (operands 2 + operand 3) into operand 0 according to the
|
|
comparison in operand 1. If the comparison is false, operand 2 is moved into
|
|
operand 0, otherwise (operand 2 + operand 3) is moved.
|
|
</p>
|
|
<a name="index-negmodecc-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>neg<var>mode</var>cc</samp>’</dt>
|
|
<dd><p>Similar to ‘<samp>mov<var>mode</var>cc</samp>’ but for conditional negation. Conditionally
|
|
move the negation of operand 2 or the unchanged operand 3 into operand 0
|
|
according to the comparison in operand 1. If the comparison is true, the negation
|
|
of operand 2 is moved into operand 0, otherwise operand 3 is moved.
|
|
</p>
|
|
<a name="index-notmodecc-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>not<var>mode</var>cc</samp>’</dt>
|
|
<dd><p>Similar to ‘<samp>neg<var>mode</var>cc</samp>’ but for conditional complement.
|
|
Conditionally move the bitwise complement of operand 2 or the unchanged
|
|
operand 3 into operand 0 according to the comparison in operand 1.
|
|
If the comparison is true, the complement of operand 2 is moved into
|
|
operand 0, otherwise operand 3 is moved.
|
|
</p>
|
|
<a name="index-cstoremode4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>cstore<var>mode</var>4</samp>’</dt>
|
|
<dd><p>Store zero or nonzero in operand 0 according to whether a comparison
|
|
is true. Operand 1 is a comparison operator. Operand 2 and operand 3
|
|
are the first and second operand of the comparison, respectively.
|
|
You specify the mode that operand 0 must have when you write the
|
|
<code>match_operand</code> expression. The compiler automatically sees which
|
|
mode you have used and supplies an operand of that mode.
|
|
</p>
|
|
<p>The value stored for a true condition must have 1 as its low bit, or
|
|
else must be negative. Otherwise the instruction is not suitable and
|
|
you should omit it from the machine description. You describe to the
|
|
compiler exactly which value is stored by defining the macro
|
|
<code>STORE_FLAG_VALUE</code> (see <a href="Misc.html#Misc">Misc</a>). If a description cannot be
|
|
found that can be used for all the possible comparison operators, you
|
|
should pick one and use a <code>define_expand</code> to map all results
|
|
onto the one you chose.
|
|
</p>
|
|
<p>These operations may <code>FAIL</code>, but should do so only in relatively
|
|
uncommon cases; if they would <code>FAIL</code> for common cases involving
|
|
integer comparisons, it is best to restrict the predicates to not
|
|
allow these operands. Likewise if a given comparison operator will
|
|
always fail, independent of the operands (for floating-point modes, the
|
|
<code>ordered_comparison_operator</code> predicate is often useful in this case).
|
|
</p>
|
|
<p>If this pattern is omitted, the compiler will generate a conditional
|
|
branch—for example, it may copy a constant one to the target and branching
|
|
around an assignment of zero to the target—or a libcall. If the predicate
|
|
for operand 1 only rejects some operators, it will also try reordering the
|
|
operands and/or inverting the result value (e.g. by an exclusive OR).
|
|
These possibilities could be cheaper or equivalent to the instructions
|
|
used for the ‘<samp>cstore<var>mode</var>4</samp>’ pattern followed by those required
|
|
to convert a positive result from <code>STORE_FLAG_VALUE</code> to 1; in this
|
|
case, you can and should make operand 1’s predicate reject some operators
|
|
in the ‘<samp>cstore<var>mode</var>4</samp>’ pattern, or remove the pattern altogether
|
|
from the machine description.
|
|
</p>
|
|
<a name="index-cbranchmode4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>cbranch<var>mode</var>4</samp>’</dt>
|
|
<dd><p>Conditional branch instruction combined with a compare instruction.
|
|
Operand 0 is a comparison operator. Operand 1 and operand 2 are the
|
|
first and second operands of the comparison, respectively. Operand 3
|
|
is the <code>code_label</code> to jump to.
|
|
</p>
|
|
<a name="index-jump-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>jump</samp>’</dt>
|
|
<dd><p>A jump inside a function; an unconditional branch. Operand 0 is the
|
|
<code>code_label</code> to jump to. This pattern name is mandatory on all
|
|
machines.
|
|
</p>
|
|
<a name="index-call-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>call</samp>’</dt>
|
|
<dd><p>Subroutine call instruction returning no value. Operand 0 is the
|
|
function to call; operand 1 is the number of bytes of arguments pushed
|
|
as a <code>const_int</code>; operand 2 is the number of registers used as
|
|
operands.
|
|
</p>
|
|
<p>On most machines, operand 2 is not actually stored into the RTL
|
|
pattern. It is supplied for the sake of some RISC machines which need
|
|
to put this information into the assembler code; they can put it in
|
|
the RTL instead of operand 1.
|
|
</p>
|
|
<p>Operand 0 should be a <code>mem</code> RTX whose address is the address of the
|
|
function. Note, however, that this address can be a <code>symbol_ref</code>
|
|
expression even if it would not be a legitimate memory address on the
|
|
target machine. If it is also not a valid argument for a call
|
|
instruction, the pattern for this operation should be a
|
|
<code>define_expand</code> (see <a href="Expander-Definitions.html#Expander-Definitions">Expander Definitions</a>) that places the
|
|
address into a register and uses that register in the call instruction.
|
|
</p>
|
|
<a name="index-call_005fvalue-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>call_value</samp>’</dt>
|
|
<dd><p>Subroutine call instruction returning a value. Operand 0 is the hard
|
|
register in which the value is returned. There are three more
|
|
operands, the same as the three operands of the ‘<samp>call</samp>’
|
|
instruction (but with numbers increased by one).
|
|
</p>
|
|
<p>Subroutines that return <code>BLKmode</code> objects use the ‘<samp>call</samp>’
|
|
insn.
|
|
</p>
|
|
<a name="index-call_005fpop-instruction-pattern"></a>
|
|
<a name="index-call_005fvalue_005fpop-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>call_pop</samp>’, ‘<samp>call_value_pop</samp>’</dt>
|
|
<dd><p>Similar to ‘<samp>call</samp>’ and ‘<samp>call_value</samp>’, except used if defined and
|
|
if <code>RETURN_POPS_ARGS</code> is nonzero. They should emit a <code>parallel</code>
|
|
that contains both the function call and a <code>set</code> to indicate the
|
|
adjustment made to the frame pointer.
|
|
</p>
|
|
<p>For machines where <code>RETURN_POPS_ARGS</code> can be nonzero, the use of these
|
|
patterns increases the number of functions for which the frame pointer
|
|
can be eliminated, if desired.
|
|
</p>
|
|
<a name="index-untyped_005fcall-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>untyped_call</samp>’</dt>
|
|
<dd><p>Subroutine call instruction returning a value of any type. Operand 0 is
|
|
the function to call; operand 1 is a memory location where the result of
|
|
calling the function is to be stored; operand 2 is a <code>parallel</code>
|
|
expression where each element is a <code>set</code> expression that indicates
|
|
the saving of a function return value into the result block.
|
|
</p>
|
|
<p>This instruction pattern should be defined to support
|
|
<code>__builtin_apply</code> on machines where special instructions are needed
|
|
to call a subroutine with arbitrary arguments or to save the value
|
|
returned. This instruction pattern is required on machines that have
|
|
multiple registers that can hold a return value
|
|
(i.e. <code>FUNCTION_VALUE_REGNO_P</code> is true for more than one register).
|
|
</p>
|
|
<a name="index-return-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>return</samp>’</dt>
|
|
<dd><p>Subroutine return instruction. This instruction pattern name should be
|
|
defined only if a single instruction can do all the work of returning
|
|
from a function.
|
|
</p>
|
|
<p>Like the ‘<samp>mov<var>m</var></samp>’ patterns, this pattern is also used after the
|
|
RTL generation phase. In this case it is to support machines where
|
|
multiple instructions are usually needed to return from a function, but
|
|
some class of functions only requires one instruction to implement a
|
|
return. Normally, the applicable functions are those which do not need
|
|
to save any registers or allocate stack space.
|
|
</p>
|
|
<p>It is valid for this pattern to expand to an instruction using
|
|
<code>simple_return</code> if no epilogue is required.
|
|
</p>
|
|
<a name="index-simple_005freturn-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>simple_return</samp>’</dt>
|
|
<dd><p>Subroutine return instruction. This instruction pattern name should be
|
|
defined only if a single instruction can do all the work of returning
|
|
from a function on a path where no epilogue is required. This pattern
|
|
is very similar to the <code>return</code> instruction pattern, but it is emitted
|
|
only by the shrink-wrapping optimization on paths where the function
|
|
prologue has not been executed, and a function return should occur without
|
|
any of the effects of the epilogue. Additional uses may be introduced on
|
|
paths where both the prologue and the epilogue have executed.
|
|
</p>
|
|
<a name="index-reload_005fcompleted"></a>
|
|
<a name="index-leaf_005ffunction_005fp"></a>
|
|
<p>For such machines, the condition specified in this pattern should only
|
|
be true when <code>reload_completed</code> is nonzero and the function’s
|
|
epilogue would only be a single instruction. For machines with register
|
|
windows, the routine <code>leaf_function_p</code> may be used to determine if
|
|
a register window push is required.
|
|
</p>
|
|
<p>Machines that have conditional return instructions should define patterns
|
|
such as
|
|
</p>
|
|
<div class="smallexample">
|
|
<pre class="smallexample">(define_insn ""
|
|
[(set (pc)
|
|
(if_then_else (match_operator
|
|
0 "comparison_operator"
|
|
[(cc0) (const_int 0)])
|
|
(return)
|
|
(pc)))]
|
|
"<var>condition</var>"
|
|
"…")
|
|
</pre></div>
|
|
|
|
<p>where <var>condition</var> would normally be the same condition specified on the
|
|
named ‘<samp>return</samp>’ pattern.
|
|
</p>
|
|
<a name="index-untyped_005freturn-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>untyped_return</samp>’</dt>
|
|
<dd><p>Untyped subroutine return instruction. This instruction pattern should
|
|
be defined to support <code>__builtin_return</code> on machines where special
|
|
instructions are needed to return a value of any type.
|
|
</p>
|
|
<p>Operand 0 is a memory location where the result of calling a function
|
|
with <code>__builtin_apply</code> is stored; operand 1 is a <code>parallel</code>
|
|
expression where each element is a <code>set</code> expression that indicates
|
|
the restoring of a function return value from the result block.
|
|
</p>
|
|
<a name="index-nop-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>nop</samp>’</dt>
|
|
<dd><p>No-op instruction. This instruction pattern name should always be defined
|
|
to output a no-op in assembler code. <code>(const_int 0)</code> will do as an
|
|
RTL pattern.
|
|
</p>
|
|
<a name="index-indirect_005fjump-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>indirect_jump</samp>’</dt>
|
|
<dd><p>An instruction to jump to an address which is operand zero.
|
|
This pattern name is mandatory on all machines.
|
|
</p>
|
|
<a name="index-casesi-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>casesi</samp>’</dt>
|
|
<dd><p>Instruction to jump through a dispatch table, including bounds checking.
|
|
This instruction takes five operands:
|
|
</p>
|
|
<ol>
|
|
<li> The index to dispatch on, which has mode <code>SImode</code>.
|
|
|
|
</li><li> The lower bound for indices in the table, an integer constant.
|
|
|
|
</li><li> The total range of indices in the table—the largest index
|
|
minus the smallest one (both inclusive).
|
|
|
|
</li><li> A label that precedes the table itself.
|
|
|
|
</li><li> A label to jump to if the index has a value outside the bounds.
|
|
</li></ol>
|
|
|
|
<p>The table is an <code>addr_vec</code> or <code>addr_diff_vec</code> inside of a
|
|
<code>jump_table_data</code>. The number of elements in the table is one plus the
|
|
difference between the upper bound and the lower bound.
|
|
</p>
|
|
<a name="index-tablejump-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>tablejump</samp>’</dt>
|
|
<dd><p>Instruction to jump to a variable address. This is a low-level
|
|
capability which can be used to implement a dispatch table when there
|
|
is no ‘<samp>casesi</samp>’ pattern.
|
|
</p>
|
|
<p>This pattern requires two operands: the address or offset, and a label
|
|
which should immediately precede the jump table. If the macro
|
|
<code>CASE_VECTOR_PC_RELATIVE</code> evaluates to a nonzero value then the first
|
|
operand is an offset which counts from the address of the table; otherwise,
|
|
it is an absolute address to jump to. In either case, the first operand has
|
|
mode <code>Pmode</code>.
|
|
</p>
|
|
<p>The ‘<samp>tablejump</samp>’ insn is always the last insn before the jump
|
|
table it uses. Its assembler code normally has no need to use the
|
|
second operand, but you should incorporate it in the RTL pattern so
|
|
that the jump optimizer will not delete the table as unreachable code.
|
|
</p>
|
|
|
|
<a name="index-decrement_005fand_005fbranch_005funtil_005fzero-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>decrement_and_branch_until_zero</samp>’</dt>
|
|
<dd><p>Conditional branch instruction that decrements a register and
|
|
jumps if the register is nonzero. Operand 0 is the register to
|
|
decrement and test; operand 1 is the label to jump to if the
|
|
register is nonzero. See <a href="Looping-Patterns.html#Looping-Patterns">Looping Patterns</a>.
|
|
</p>
|
|
<p>This optional instruction pattern is only used by the combiner,
|
|
typically for loops reversed by the loop optimizer when strength
|
|
reduction is enabled.
|
|
</p>
|
|
<a name="index-doloop_005fend-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>doloop_end</samp>’</dt>
|
|
<dd><p>Conditional branch instruction that decrements a register and
|
|
jumps if the register is nonzero. Operand 0 is the register to
|
|
decrement and test; operand 1 is the label to jump to if the
|
|
register is nonzero.
|
|
See <a href="Looping-Patterns.html#Looping-Patterns">Looping Patterns</a>.
|
|
</p>
|
|
<p>This optional instruction pattern should be defined for machines with
|
|
low-overhead looping instructions as the loop optimizer will try to
|
|
modify suitable loops to utilize it. The target hook
|
|
<code>TARGET_CAN_USE_DOLOOP_P</code> controls the conditions under which
|
|
low-overhead loops can be used.
|
|
</p>
|
|
<a name="index-doloop_005fbegin-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>doloop_begin</samp>’</dt>
|
|
<dd><p>Companion instruction to <code>doloop_end</code> required for machines that
|
|
need to perform some initialization, such as loading a special counter
|
|
register. Operand 1 is the associated <code>doloop_end</code> pattern and
|
|
operand 0 is the register that it decrements.
|
|
</p>
|
|
<p>If initialization insns do not always need to be emitted, use a
|
|
<code>define_expand</code> (see <a href="Expander-Definitions.html#Expander-Definitions">Expander Definitions</a>) and make it fail.
|
|
</p>
|
|
<a name="index-canonicalize_005ffuncptr_005ffor_005fcompare-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>canonicalize_funcptr_for_compare</samp>’</dt>
|
|
<dd><p>Canonicalize the function pointer in operand 1 and store the result
|
|
into operand 0.
|
|
</p>
|
|
<p>Operand 0 is always a <code>reg</code> and has mode <code>Pmode</code>; operand 1
|
|
may be a <code>reg</code>, <code>mem</code>, <code>symbol_ref</code>, <code>const_int</code>, etc
|
|
and also has mode <code>Pmode</code>.
|
|
</p>
|
|
<p>Canonicalization of a function pointer usually involves computing
|
|
the address of the function which would be called if the function
|
|
pointer were used in an indirect call.
|
|
</p>
|
|
<p>Only define this pattern if function pointers on the target machine
|
|
can have different values but still call the same function when
|
|
used in an indirect call.
|
|
</p>
|
|
<a name="index-save_005fstack_005fblock-instruction-pattern"></a>
|
|
<a name="index-save_005fstack_005ffunction-instruction-pattern"></a>
|
|
<a name="index-save_005fstack_005fnonlocal-instruction-pattern"></a>
|
|
<a name="index-restore_005fstack_005fblock-instruction-pattern"></a>
|
|
<a name="index-restore_005fstack_005ffunction-instruction-pattern"></a>
|
|
<a name="index-restore_005fstack_005fnonlocal-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>save_stack_block</samp>’</dt>
|
|
<dt>‘<samp>save_stack_function</samp>’</dt>
|
|
<dt>‘<samp>save_stack_nonlocal</samp>’</dt>
|
|
<dt>‘<samp>restore_stack_block</samp>’</dt>
|
|
<dt>‘<samp>restore_stack_function</samp>’</dt>
|
|
<dt>‘<samp>restore_stack_nonlocal</samp>’</dt>
|
|
<dd><p>Most machines save and restore the stack pointer by copying it to or
|
|
from an object of mode <code>Pmode</code>. Do not define these patterns on
|
|
such machines.
|
|
</p>
|
|
<p>Some machines require special handling for stack pointer saves and
|
|
restores. On those machines, define the patterns corresponding to the
|
|
non-standard cases by using a <code>define_expand</code> (see <a href="Expander-Definitions.html#Expander-Definitions">Expander Definitions</a>) that produces the required insns. The three types of
|
|
saves and restores are:
|
|
</p>
|
|
<ol>
|
|
<li> ‘<samp>save_stack_block</samp>’ saves the stack pointer at the start of a block
|
|
that allocates a variable-sized object, and ‘<samp>restore_stack_block</samp>’
|
|
restores the stack pointer when the block is exited.
|
|
|
|
</li><li> ‘<samp>save_stack_function</samp>’ and ‘<samp>restore_stack_function</samp>’ do a
|
|
similar job for the outermost block of a function and are used when the
|
|
function allocates variable-sized objects or calls <code>alloca</code>. Only
|
|
the epilogue uses the restored stack pointer, allowing a simpler save or
|
|
restore sequence on some machines.
|
|
|
|
</li><li> ‘<samp>save_stack_nonlocal</samp>’ is used in functions that contain labels
|
|
branched to by nested functions. It saves the stack pointer in such a
|
|
way that the inner function can use ‘<samp>restore_stack_nonlocal</samp>’ to
|
|
restore the stack pointer. The compiler generates code to restore the
|
|
frame and argument pointer registers, but some machines require saving
|
|
and restoring additional data such as register window information or
|
|
stack backchains. Place insns in these patterns to save and restore any
|
|
such required data.
|
|
</li></ol>
|
|
|
|
<p>When saving the stack pointer, operand 0 is the save area and operand 1
|
|
is the stack pointer. The mode used to allocate the save area defaults
|
|
to <code>Pmode</code> but you can override that choice by defining the
|
|
<code>STACK_SAVEAREA_MODE</code> macro (see <a href="Storage-Layout.html#Storage-Layout">Storage Layout</a>). You must
|
|
specify an integral mode, or <code>VOIDmode</code> if no save area is needed
|
|
for a particular type of save (either because no save is needed or
|
|
because a machine-specific save area can be used). Operand 0 is the
|
|
stack pointer and operand 1 is the save area for restore operations. If
|
|
‘<samp>save_stack_block</samp>’ is defined, operand 0 must not be
|
|
<code>VOIDmode</code> since these saves can be arbitrarily nested.
|
|
</p>
|
|
<p>A save area is a <code>mem</code> that is at a constant offset from
|
|
<code>virtual_stack_vars_rtx</code> when the stack pointer is saved for use by
|
|
nonlocal gotos and a <code>reg</code> in the other two cases.
|
|
</p>
|
|
<a name="index-allocate_005fstack-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>allocate_stack</samp>’</dt>
|
|
<dd><p>Subtract (or add if <code>STACK_GROWS_DOWNWARD</code> is undefined) operand 1 from
|
|
the stack pointer to create space for dynamically allocated data.
|
|
</p>
|
|
<p>Store the resultant pointer to this space into operand 0. If you
|
|
are allocating space from the main stack, do this by emitting a
|
|
move insn to copy <code>virtual_stack_dynamic_rtx</code> to operand 0.
|
|
If you are allocating the space elsewhere, generate code to copy the
|
|
location of the space to operand 0. In the latter case, you must
|
|
ensure this space gets freed when the corresponding space on the main
|
|
stack is free.
|
|
</p>
|
|
<p>Do not define this pattern if all that must be done is the subtraction.
|
|
Some machines require other operations such as stack probes or
|
|
maintaining the back chain. Define this pattern to emit those
|
|
operations in addition to updating the stack pointer.
|
|
</p>
|
|
<a name="index-check_005fstack-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>check_stack</samp>’</dt>
|
|
<dd><p>If stack checking (see <a href="Stack-Checking.html#Stack-Checking">Stack Checking</a>) cannot be done on your system by
|
|
probing the stack, define this pattern to perform the needed check and signal
|
|
an error if the stack has overflowed. The single operand is the address in
|
|
the stack farthest from the current stack pointer that you need to validate.
|
|
Normally, on platforms where this pattern is needed, you would obtain the
|
|
stack limit from a global or thread-specific variable or register.
|
|
</p>
|
|
<a name="index-probe_005fstack_005faddress-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>probe_stack_address</samp>’</dt>
|
|
<dd><p>If stack checking (see <a href="Stack-Checking.html#Stack-Checking">Stack Checking</a>) can be done on your system by
|
|
probing the stack but without the need to actually access it, define this
|
|
pattern and signal an error if the stack has overflowed. The single operand
|
|
is the memory address in the stack that needs to be probed.
|
|
</p>
|
|
<a name="index-probe_005fstack-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>probe_stack</samp>’</dt>
|
|
<dd><p>If stack checking (see <a href="Stack-Checking.html#Stack-Checking">Stack Checking</a>) can be done on your system by
|
|
probing the stack but doing it with a “store zero” instruction is not valid
|
|
or optimal, define this pattern to do the probing differently and signal an
|
|
error if the stack has overflowed. The single operand is the memory reference
|
|
in the stack that needs to be probed.
|
|
</p>
|
|
<a name="index-nonlocal_005fgoto-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>nonlocal_goto</samp>’</dt>
|
|
<dd><p>Emit code to generate a non-local goto, e.g., a jump from one function
|
|
to a label in an outer function. This pattern has four arguments,
|
|
each representing a value to be used in the jump. The first
|
|
argument is to be loaded into the frame pointer, the second is
|
|
the address to branch to (code to dispatch to the actual label),
|
|
the third is the address of a location where the stack is saved,
|
|
and the last is the address of the label, to be placed in the
|
|
location for the incoming static chain.
|
|
</p>
|
|
<p>On most machines you need not define this pattern, since GCC will
|
|
already generate the correct code, which is to load the frame pointer
|
|
and static chain, restore the stack (using the
|
|
‘<samp>restore_stack_nonlocal</samp>’ pattern, if defined), and jump indirectly
|
|
to the dispatcher. You need only define this pattern if this code will
|
|
not work on your machine.
|
|
</p>
|
|
<a name="index-nonlocal_005fgoto_005freceiver-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>nonlocal_goto_receiver</samp>’</dt>
|
|
<dd><p>This pattern, if defined, contains code needed at the target of a
|
|
nonlocal goto after the code already generated by GCC. You will not
|
|
normally need to define this pattern. A typical reason why you might
|
|
need this pattern is if some value, such as a pointer to a global table,
|
|
must be restored when the frame pointer is restored. Note that a nonlocal
|
|
goto only occurs within a unit-of-translation, so a global table pointer
|
|
that is shared by all functions of a given module need not be restored.
|
|
There are no arguments.
|
|
</p>
|
|
<a name="index-exception_005freceiver-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>exception_receiver</samp>’</dt>
|
|
<dd><p>This pattern, if defined, contains code needed at the site of an
|
|
exception handler that isn’t needed at the site of a nonlocal goto. You
|
|
will not normally need to define this pattern. A typical reason why you
|
|
might need this pattern is if some value, such as a pointer to a global
|
|
table, must be restored after control flow is branched to the handler of
|
|
an exception. There are no arguments.
|
|
</p>
|
|
<a name="index-builtin_005fsetjmp_005fsetup-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>builtin_setjmp_setup</samp>’</dt>
|
|
<dd><p>This pattern, if defined, contains additional code needed to initialize
|
|
the <code>jmp_buf</code>. You will not normally need to define this pattern.
|
|
A typical reason why you might need this pattern is if some value, such
|
|
as a pointer to a global table, must be restored. Though it is
|
|
preferred that the pointer value be recalculated if possible (given the
|
|
address of a label for instance). The single argument is a pointer to
|
|
the <code>jmp_buf</code>. Note that the buffer is five words long and that
|
|
the first three are normally used by the generic mechanism.
|
|
</p>
|
|
<a name="index-builtin_005fsetjmp_005freceiver-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>builtin_setjmp_receiver</samp>’</dt>
|
|
<dd><p>This pattern, if defined, contains code needed at the site of a
|
|
built-in setjmp that isn’t needed at the site of a nonlocal goto. You
|
|
will not normally need to define this pattern. A typical reason why you
|
|
might need this pattern is if some value, such as a pointer to a global
|
|
table, must be restored. It takes one argument, which is the label
|
|
to which builtin_longjmp transferred control; this pattern may be emitted
|
|
at a small offset from that label.
|
|
</p>
|
|
<a name="index-builtin_005flongjmp-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>builtin_longjmp</samp>’</dt>
|
|
<dd><p>This pattern, if defined, performs the entire action of the longjmp.
|
|
You will not normally need to define this pattern unless you also define
|
|
<code>builtin_setjmp_setup</code>. The single argument is a pointer to the
|
|
<code>jmp_buf</code>.
|
|
</p>
|
|
<a name="index-eh_005freturn-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>eh_return</samp>’</dt>
|
|
<dd><p>This pattern, if defined, affects the way <code>__builtin_eh_return</code>,
|
|
and thence the call frame exception handling library routines, are
|
|
built. It is intended to handle non-trivial actions needed along
|
|
the abnormal return path.
|
|
</p>
|
|
<p>The address of the exception handler to which the function should return
|
|
is passed as operand to this pattern. It will normally need to copied by
|
|
the pattern to some special register or memory location.
|
|
If the pattern needs to determine the location of the target call
|
|
frame in order to do so, it may use <code>EH_RETURN_STACKADJ_RTX</code>,
|
|
if defined; it will have already been assigned.
|
|
</p>
|
|
<p>If this pattern is not defined, the default action will be to simply
|
|
copy the return address to <code>EH_RETURN_HANDLER_RTX</code>. Either
|
|
that macro or this pattern needs to be defined if call frame exception
|
|
handling is to be used.
|
|
</p>
|
|
<a name="index-prologue-instruction-pattern"></a>
|
|
<a name="prologue-instruction-pattern"></a></dd>
|
|
<dt>‘<samp>prologue</samp>’</dt>
|
|
<dd><p>This pattern, if defined, emits RTL for entry to a function. The function
|
|
entry is responsible for setting up the stack frame, initializing the frame
|
|
pointer register, saving callee saved registers, etc.
|
|
</p>
|
|
<p>Using a prologue pattern is generally preferred over defining
|
|
<code>TARGET_ASM_FUNCTION_PROLOGUE</code> to emit assembly code for the prologue.
|
|
</p>
|
|
<p>The <code>prologue</code> pattern is particularly useful for targets which perform
|
|
instruction scheduling.
|
|
</p>
|
|
<a name="index-window_005fsave-instruction-pattern"></a>
|
|
<a name="window_005fsave-instruction-pattern"></a></dd>
|
|
<dt>‘<samp>window_save</samp>’</dt>
|
|
<dd><p>This pattern, if defined, emits RTL for a register window save. It should
|
|
be defined if the target machine has register windows but the window events
|
|
are decoupled from calls to subroutines. The canonical example is the SPARC
|
|
architecture.
|
|
</p>
|
|
<a name="index-epilogue-instruction-pattern"></a>
|
|
<a name="epilogue-instruction-pattern"></a></dd>
|
|
<dt>‘<samp>epilogue</samp>’</dt>
|
|
<dd><p>This pattern emits RTL for exit from a function. The function
|
|
exit is responsible for deallocating the stack frame, restoring callee saved
|
|
registers and emitting the return instruction.
|
|
</p>
|
|
<p>Using an epilogue pattern is generally preferred over defining
|
|
<code>TARGET_ASM_FUNCTION_EPILOGUE</code> to emit assembly code for the epilogue.
|
|
</p>
|
|
<p>The <code>epilogue</code> pattern is particularly useful for targets which perform
|
|
instruction scheduling or which have delay slots for their return instruction.
|
|
</p>
|
|
<a name="index-sibcall_005fepilogue-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>sibcall_epilogue</samp>’</dt>
|
|
<dd><p>This pattern, if defined, emits RTL for exit from a function without the final
|
|
branch back to the calling function. This pattern will be emitted before any
|
|
sibling call (aka tail call) sites.
|
|
</p>
|
|
<p>The <code>sibcall_epilogue</code> pattern must not clobber any arguments used for
|
|
parameter passing or any stack slots for arguments passed to the current
|
|
function.
|
|
</p>
|
|
<a name="index-trap-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>trap</samp>’</dt>
|
|
<dd><p>This pattern, if defined, signals an error, typically by causing some
|
|
kind of signal to be raised. Among other places, it is used by the Java
|
|
front end to signal ‘invalid array index’ exceptions.
|
|
</p>
|
|
<a name="index-ctrapMM4-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>ctrap<var>MM</var>4</samp>’</dt>
|
|
<dd><p>Conditional trap instruction. Operand 0 is a piece of RTL which
|
|
performs a comparison, and operands 1 and 2 are the arms of the
|
|
comparison. Operand 3 is the trap code, an integer.
|
|
</p>
|
|
<p>A typical <code>ctrap</code> pattern looks like
|
|
</p>
|
|
<div class="smallexample">
|
|
<pre class="smallexample">(define_insn "ctrapsi4"
|
|
[(trap_if (match_operator 0 "trap_operator"
|
|
[(match_operand 1 "register_operand")
|
|
(match_operand 2 "immediate_operand")])
|
|
(match_operand 3 "const_int_operand" "i"))]
|
|
""
|
|
"…")
|
|
</pre></div>
|
|
|
|
<a name="index-prefetch-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>prefetch</samp>’</dt>
|
|
<dd><p>This pattern, if defined, emits code for a non-faulting data prefetch
|
|
instruction. Operand 0 is the address of the memory to prefetch. Operand 1
|
|
is a constant 1 if the prefetch is preparing for a write to the memory
|
|
address, or a constant 0 otherwise. Operand 2 is the expected degree of
|
|
temporal locality of the data and is a value between 0 and 3, inclusive; 0
|
|
means that the data has no temporal locality, so it need not be left in the
|
|
cache after the access; 3 means that the data has a high degree of temporal
|
|
locality and should be left in all levels of cache possible; 1 and 2 mean,
|
|
respectively, a low or moderate degree of temporal locality.
|
|
</p>
|
|
<p>Targets that do not support write prefetches or locality hints can ignore
|
|
the values of operands 1 and 2.
|
|
</p>
|
|
<a name="index-blockage-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>blockage</samp>’</dt>
|
|
<dd><p>This pattern defines a pseudo insn that prevents the instruction
|
|
scheduler and other passes from moving instructions and using register
|
|
equivalences across the boundary defined by the blockage insn.
|
|
This needs to be an UNSPEC_VOLATILE pattern or a volatile ASM.
|
|
</p>
|
|
<a name="index-memory_005fbarrier-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>memory_barrier</samp>’</dt>
|
|
<dd><p>If the target memory model is not fully synchronous, then this pattern
|
|
should be defined to an instruction that orders both loads and stores
|
|
before the instruction with respect to loads and stores after the instruction.
|
|
This pattern has no operands.
|
|
</p>
|
|
<a name="index-sync_005fcompare_005fand_005fswapmode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>sync_compare_and_swap<var>mode</var></samp>’</dt>
|
|
<dd><p>This pattern, if defined, emits code for an atomic compare-and-swap
|
|
operation. Operand 1 is the memory on which the atomic operation is
|
|
performed. Operand 2 is the “old” value to be compared against the
|
|
current contents of the memory location. Operand 3 is the “new” value
|
|
to store in the memory if the compare succeeds. Operand 0 is the result
|
|
of the operation; it should contain the contents of the memory
|
|
before the operation. If the compare succeeds, this should obviously be
|
|
a copy of operand 2.
|
|
</p>
|
|
<p>This pattern must show that both operand 0 and operand 1 are modified.
|
|
</p>
|
|
<p>This pattern must issue any memory barrier instructions such that all
|
|
memory operations before the atomic operation occur before the atomic
|
|
operation and all memory operations after the atomic operation occur
|
|
after the atomic operation.
|
|
</p>
|
|
<p>For targets where the success or failure of the compare-and-swap
|
|
operation is available via the status flags, it is possible to
|
|
avoid a separate compare operation and issue the subsequent
|
|
branch or store-flag operation immediately after the compare-and-swap.
|
|
To this end, GCC will look for a <code>MODE_CC</code> set in the
|
|
output of <code>sync_compare_and_swap<var>mode</var></code>; if the machine
|
|
description includes such a set, the target should also define special
|
|
<code>cbranchcc4</code> and/or <code>cstorecc4</code> instructions. GCC will then
|
|
be able to take the destination of the <code>MODE_CC</code> set and pass it
|
|
to the <code>cbranchcc4</code> or <code>cstorecc4</code> pattern as the first
|
|
operand of the comparison (the second will be <code>(const_int 0)</code>).
|
|
</p>
|
|
<p>For targets where the operating system may provide support for this
|
|
operation via library calls, the <code>sync_compare_and_swap_optab</code>
|
|
may be initialized to a function with the same interface as the
|
|
<code>__sync_val_compare_and_swap_<var>n</var></code> built-in. If the entire
|
|
set of <var>__sync</var> builtins are supported via library calls, the
|
|
target can initialize all of the optabs at once with
|
|
<code>init_sync_libfuncs</code>.
|
|
For the purposes of C++11 <code>std::atomic::is_lock_free</code>, it is
|
|
assumed that these library calls do <em>not</em> use any kind of
|
|
interruptable locking.
|
|
</p>
|
|
<a name="index-sync_005faddmode-instruction-pattern"></a>
|
|
<a name="index-sync_005fsubmode-instruction-pattern"></a>
|
|
<a name="index-sync_005fiormode-instruction-pattern"></a>
|
|
<a name="index-sync_005fandmode-instruction-pattern"></a>
|
|
<a name="index-sync_005fxormode-instruction-pattern"></a>
|
|
<a name="index-sync_005fnandmode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>sync_add<var>mode</var></samp>’, ‘<samp>sync_sub<var>mode</var></samp>’</dt>
|
|
<dt>‘<samp>sync_ior<var>mode</var></samp>’, ‘<samp>sync_and<var>mode</var></samp>’</dt>
|
|
<dt>‘<samp>sync_xor<var>mode</var></samp>’, ‘<samp>sync_nand<var>mode</var></samp>’</dt>
|
|
<dd><p>These patterns emit code for an atomic operation on memory.
|
|
Operand 0 is the memory on which the atomic operation is performed.
|
|
Operand 1 is the second operand to the binary operator.
|
|
</p>
|
|
<p>This pattern must issue any memory barrier instructions such that all
|
|
memory operations before the atomic operation occur before the atomic
|
|
operation and all memory operations after the atomic operation occur
|
|
after the atomic operation.
|
|
</p>
|
|
<p>If these patterns are not defined, the operation will be constructed
|
|
from a compare-and-swap operation, if defined.
|
|
</p>
|
|
<a name="index-sync_005fold_005faddmode-instruction-pattern"></a>
|
|
<a name="index-sync_005fold_005fsubmode-instruction-pattern"></a>
|
|
<a name="index-sync_005fold_005fiormode-instruction-pattern"></a>
|
|
<a name="index-sync_005fold_005fandmode-instruction-pattern"></a>
|
|
<a name="index-sync_005fold_005fxormode-instruction-pattern"></a>
|
|
<a name="index-sync_005fold_005fnandmode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>sync_old_add<var>mode</var></samp>’, ‘<samp>sync_old_sub<var>mode</var></samp>’</dt>
|
|
<dt>‘<samp>sync_old_ior<var>mode</var></samp>’, ‘<samp>sync_old_and<var>mode</var></samp>’</dt>
|
|
<dt>‘<samp>sync_old_xor<var>mode</var></samp>’, ‘<samp>sync_old_nand<var>mode</var></samp>’</dt>
|
|
<dd><p>These patterns emit code for an atomic operation on memory,
|
|
and return the value that the memory contained before the operation.
|
|
Operand 0 is the result value, operand 1 is the memory on which the
|
|
atomic operation is performed, and operand 2 is the second operand
|
|
to the binary operator.
|
|
</p>
|
|
<p>This pattern must issue any memory barrier instructions such that all
|
|
memory operations before the atomic operation occur before the atomic
|
|
operation and all memory operations after the atomic operation occur
|
|
after the atomic operation.
|
|
</p>
|
|
<p>If these patterns are not defined, the operation will be constructed
|
|
from a compare-and-swap operation, if defined.
|
|
</p>
|
|
<a name="index-sync_005fnew_005faddmode-instruction-pattern"></a>
|
|
<a name="index-sync_005fnew_005fsubmode-instruction-pattern"></a>
|
|
<a name="index-sync_005fnew_005fiormode-instruction-pattern"></a>
|
|
<a name="index-sync_005fnew_005fandmode-instruction-pattern"></a>
|
|
<a name="index-sync_005fnew_005fxormode-instruction-pattern"></a>
|
|
<a name="index-sync_005fnew_005fnandmode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>sync_new_add<var>mode</var></samp>’, ‘<samp>sync_new_sub<var>mode</var></samp>’</dt>
|
|
<dt>‘<samp>sync_new_ior<var>mode</var></samp>’, ‘<samp>sync_new_and<var>mode</var></samp>’</dt>
|
|
<dt>‘<samp>sync_new_xor<var>mode</var></samp>’, ‘<samp>sync_new_nand<var>mode</var></samp>’</dt>
|
|
<dd><p>These patterns are like their <code>sync_old_<var>op</var></code> counterparts,
|
|
except that they return the value that exists in the memory location
|
|
after the operation, rather than before the operation.
|
|
</p>
|
|
<a name="index-sync_005flock_005ftest_005fand_005fsetmode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>sync_lock_test_and_set<var>mode</var></samp>’</dt>
|
|
<dd><p>This pattern takes two forms, based on the capabilities of the target.
|
|
In either case, operand 0 is the result of the operand, operand 1 is
|
|
the memory on which the atomic operation is performed, and operand 2
|
|
is the value to set in the lock.
|
|
</p>
|
|
<p>In the ideal case, this operation is an atomic exchange operation, in
|
|
which the previous value in memory operand is copied into the result
|
|
operand, and the value operand is stored in the memory operand.
|
|
</p>
|
|
<p>For less capable targets, any value operand that is not the constant 1
|
|
should be rejected with <code>FAIL</code>. In this case the target may use
|
|
an atomic test-and-set bit operation. The result operand should contain
|
|
1 if the bit was previously set and 0 if the bit was previously clear.
|
|
The true contents of the memory operand are implementation defined.
|
|
</p>
|
|
<p>This pattern must issue any memory barrier instructions such that the
|
|
pattern as a whole acts as an acquire barrier, that is all memory
|
|
operations after the pattern do not occur until the lock is acquired.
|
|
</p>
|
|
<p>If this pattern is not defined, the operation will be constructed from
|
|
a compare-and-swap operation, if defined.
|
|
</p>
|
|
<a name="index-sync_005flock_005freleasemode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>sync_lock_release<var>mode</var></samp>’</dt>
|
|
<dd><p>This pattern, if defined, releases a lock set by
|
|
<code>sync_lock_test_and_set<var>mode</var></code>. Operand 0 is the memory
|
|
that contains the lock; operand 1 is the value to store in the lock.
|
|
</p>
|
|
<p>If the target doesn’t implement full semantics for
|
|
<code>sync_lock_test_and_set<var>mode</var></code>, any value operand which is not
|
|
the constant 0 should be rejected with <code>FAIL</code>, and the true contents
|
|
of the memory operand are implementation defined.
|
|
</p>
|
|
<p>This pattern must issue any memory barrier instructions such that the
|
|
pattern as a whole acts as a release barrier, that is the lock is
|
|
released only after all previous memory operations have completed.
|
|
</p>
|
|
<p>If this pattern is not defined, then a <code>memory_barrier</code> pattern
|
|
will be emitted, followed by a store of the value to the memory operand.
|
|
</p>
|
|
<a name="index-atomic_005fcompare_005fand_005fswapmode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>atomic_compare_and_swap<var>mode</var></samp>’</dt>
|
|
<dd><p>This pattern, if defined, emits code for an atomic compare-and-swap
|
|
operation with memory model semantics. Operand 2 is the memory on which
|
|
the atomic operation is performed. Operand 0 is an output operand which
|
|
is set to true or false based on whether the operation succeeded. Operand
|
|
1 is an output operand which is set to the contents of the memory before
|
|
the operation was attempted. Operand 3 is the value that is expected to
|
|
be in memory. Operand 4 is the value to put in memory if the expected
|
|
value is found there. Operand 5 is set to 1 if this compare and swap is to
|
|
be treated as a weak operation. Operand 6 is the memory model to be used
|
|
if the operation is a success. Operand 7 is the memory model to be used
|
|
if the operation fails.
|
|
</p>
|
|
<p>If memory referred to in operand 2 contains the value in operand 3, then
|
|
operand 4 is stored in memory pointed to by operand 2 and fencing based on
|
|
the memory model in operand 6 is issued.
|
|
</p>
|
|
<p>If memory referred to in operand 2 does not contain the value in operand 3,
|
|
then fencing based on the memory model in operand 7 is issued.
|
|
</p>
|
|
<p>If a target does not support weak compare-and-swap operations, or the port
|
|
elects not to implement weak operations, the argument in operand 5 can be
|
|
ignored. Note a strong implementation must be provided.
|
|
</p>
|
|
<p>If this pattern is not provided, the <code>__atomic_compare_exchange</code>
|
|
built-in functions will utilize the legacy <code>sync_compare_and_swap</code>
|
|
pattern with an <code>__ATOMIC_SEQ_CST</code> memory model.
|
|
</p>
|
|
<a name="index-atomic_005floadmode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>atomic_load<var>mode</var></samp>’</dt>
|
|
<dd><p>This pattern implements an atomic load operation with memory model
|
|
semantics. Operand 1 is the memory address being loaded from. Operand 0
|
|
is the result of the load. Operand 2 is the memory model to be used for
|
|
the load operation.
|
|
</p>
|
|
<p>If not present, the <code>__atomic_load</code> built-in function will either
|
|
resort to a normal load with memory barriers, or a compare-and-swap
|
|
operation if a normal load would not be atomic.
|
|
</p>
|
|
<a name="index-atomic_005fstoremode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>atomic_store<var>mode</var></samp>’</dt>
|
|
<dd><p>This pattern implements an atomic store operation with memory model
|
|
semantics. Operand 0 is the memory address being stored to. Operand 1
|
|
is the value to be written. Operand 2 is the memory model to be used for
|
|
the operation.
|
|
</p>
|
|
<p>If not present, the <code>__atomic_store</code> built-in function will attempt to
|
|
perform a normal store and surround it with any required memory fences. If
|
|
the store would not be atomic, then an <code>__atomic_exchange</code> is
|
|
attempted with the result being ignored.
|
|
</p>
|
|
<a name="index-atomic_005fexchangemode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>atomic_exchange<var>mode</var></samp>’</dt>
|
|
<dd><p>This pattern implements an atomic exchange operation with memory model
|
|
semantics. Operand 1 is the memory location the operation is performed on.
|
|
Operand 0 is an output operand which is set to the original value contained
|
|
in the memory pointed to by operand 1. Operand 2 is the value to be
|
|
stored. Operand 3 is the memory model to be used.
|
|
</p>
|
|
<p>If this pattern is not present, the built-in function
|
|
<code>__atomic_exchange</code> will attempt to preform the operation with a
|
|
compare and swap loop.
|
|
</p>
|
|
<a name="index-atomic_005faddmode-instruction-pattern"></a>
|
|
<a name="index-atomic_005fsubmode-instruction-pattern"></a>
|
|
<a name="index-atomic_005formode-instruction-pattern"></a>
|
|
<a name="index-atomic_005fandmode-instruction-pattern"></a>
|
|
<a name="index-atomic_005fxormode-instruction-pattern"></a>
|
|
<a name="index-atomic_005fnandmode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>atomic_add<var>mode</var></samp>’, ‘<samp>atomic_sub<var>mode</var></samp>’</dt>
|
|
<dt>‘<samp>atomic_or<var>mode</var></samp>’, ‘<samp>atomic_and<var>mode</var></samp>’</dt>
|
|
<dt>‘<samp>atomic_xor<var>mode</var></samp>’, ‘<samp>atomic_nand<var>mode</var></samp>’</dt>
|
|
<dd><p>These patterns emit code for an atomic operation on memory with memory
|
|
model semantics. Operand 0 is the memory on which the atomic operation is
|
|
performed. Operand 1 is the second operand to the binary operator.
|
|
Operand 2 is the memory model to be used by the operation.
|
|
</p>
|
|
<p>If these patterns are not defined, attempts will be made to use legacy
|
|
<code>sync</code> patterns, or equivalent patterns which return a result. If
|
|
none of these are available a compare-and-swap loop will be used.
|
|
</p>
|
|
<a name="index-atomic_005ffetch_005faddmode-instruction-pattern"></a>
|
|
<a name="index-atomic_005ffetch_005fsubmode-instruction-pattern"></a>
|
|
<a name="index-atomic_005ffetch_005formode-instruction-pattern"></a>
|
|
<a name="index-atomic_005ffetch_005fandmode-instruction-pattern"></a>
|
|
<a name="index-atomic_005ffetch_005fxormode-instruction-pattern"></a>
|
|
<a name="index-atomic_005ffetch_005fnandmode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>atomic_fetch_add<var>mode</var></samp>’, ‘<samp>atomic_fetch_sub<var>mode</var></samp>’</dt>
|
|
<dt>‘<samp>atomic_fetch_or<var>mode</var></samp>’, ‘<samp>atomic_fetch_and<var>mode</var></samp>’</dt>
|
|
<dt>‘<samp>atomic_fetch_xor<var>mode</var></samp>’, ‘<samp>atomic_fetch_nand<var>mode</var></samp>’</dt>
|
|
<dd><p>These patterns emit code for an atomic operation on memory with memory
|
|
model semantics, and return the original value. Operand 0 is an output
|
|
operand which contains the value of the memory location before the
|
|
operation was performed. Operand 1 is the memory on which the atomic
|
|
operation is performed. Operand 2 is the second operand to the binary
|
|
operator. Operand 3 is the memory model to be used by the operation.
|
|
</p>
|
|
<p>If these patterns are not defined, attempts will be made to use legacy
|
|
<code>sync</code> patterns. If none of these are available a compare-and-swap
|
|
loop will be used.
|
|
</p>
|
|
<a name="index-atomic_005fadd_005ffetchmode-instruction-pattern"></a>
|
|
<a name="index-atomic_005fsub_005ffetchmode-instruction-pattern"></a>
|
|
<a name="index-atomic_005for_005ffetchmode-instruction-pattern"></a>
|
|
<a name="index-atomic_005fand_005ffetchmode-instruction-pattern"></a>
|
|
<a name="index-atomic_005fxor_005ffetchmode-instruction-pattern"></a>
|
|
<a name="index-atomic_005fnand_005ffetchmode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>atomic_add_fetch<var>mode</var></samp>’, ‘<samp>atomic_sub_fetch<var>mode</var></samp>’</dt>
|
|
<dt>‘<samp>atomic_or_fetch<var>mode</var></samp>’, ‘<samp>atomic_and_fetch<var>mode</var></samp>’</dt>
|
|
<dt>‘<samp>atomic_xor_fetch<var>mode</var></samp>’, ‘<samp>atomic_nand_fetch<var>mode</var></samp>’</dt>
|
|
<dd><p>These patterns emit code for an atomic operation on memory with memory
|
|
model semantics and return the result after the operation is performed.
|
|
Operand 0 is an output operand which contains the value after the
|
|
operation. Operand 1 is the memory on which the atomic operation is
|
|
performed. Operand 2 is the second operand to the binary operator.
|
|
Operand 3 is the memory model to be used by the operation.
|
|
</p>
|
|
<p>If these patterns are not defined, attempts will be made to use legacy
|
|
<code>sync</code> patterns, or equivalent patterns which return the result before
|
|
the operation followed by the arithmetic operation required to produce the
|
|
result. If none of these are available a compare-and-swap loop will be
|
|
used.
|
|
</p>
|
|
<a name="index-atomic_005ftest_005fand_005fset-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>atomic_test_and_set</samp>’</dt>
|
|
<dd><p>This pattern emits code for <code>__builtin_atomic_test_and_set</code>.
|
|
Operand 0 is an output operand which is set to true if the previous
|
|
previous contents of the byte was "set", and false otherwise. Operand 1
|
|
is the <code>QImode</code> memory to be modified. Operand 2 is the memory
|
|
model to be used.
|
|
</p>
|
|
<p>The specific value that defines "set" is implementation defined, and
|
|
is normally based on what is performed by the native atomic test and set
|
|
instruction.
|
|
</p>
|
|
<a name="index-mem_005fthread_005ffencemode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>mem_thread_fence<var>mode</var></samp>’</dt>
|
|
<dd><p>This pattern emits code required to implement a thread fence with
|
|
memory model semantics. Operand 0 is the memory model to be used.
|
|
</p>
|
|
<p>If this pattern is not specified, all memory models except
|
|
<code>__ATOMIC_RELAXED</code> will result in issuing a <code>sync_synchronize</code>
|
|
barrier pattern.
|
|
</p>
|
|
<a name="index-mem_005fsignal_005ffencemode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>mem_signal_fence<var>mode</var></samp>’</dt>
|
|
<dd><p>This pattern emits code required to implement a signal fence with
|
|
memory model semantics. Operand 0 is the memory model to be used.
|
|
</p>
|
|
<p>This pattern should impact the compiler optimizers the same way that
|
|
mem_signal_fence does, but it does not need to issue any barrier
|
|
instructions.
|
|
</p>
|
|
<p>If this pattern is not specified, all memory models except
|
|
<code>__ATOMIC_RELAXED</code> will result in issuing a <code>sync_synchronize</code>
|
|
barrier pattern.
|
|
</p>
|
|
<a name="index-get_005fthread_005fpointermode-instruction-pattern"></a>
|
|
<a name="index-set_005fthread_005fpointermode-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>get_thread_pointer<var>mode</var></samp>’</dt>
|
|
<dt>‘<samp>set_thread_pointer<var>mode</var></samp>’</dt>
|
|
<dd><p>These patterns emit code that reads/sets the TLS thread pointer. Currently,
|
|
these are only needed if the target needs to support the
|
|
<code>__builtin_thread_pointer</code> and <code>__builtin_set_thread_pointer</code>
|
|
builtins.
|
|
</p>
|
|
<p>The get/set patterns have a single output/input operand respectively,
|
|
with <var>mode</var> intended to be <code>Pmode</code>.
|
|
</p>
|
|
<a name="index-stack_005fprotect_005fset-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>stack_protect_set</samp>’</dt>
|
|
<dd><p>This pattern, if defined, moves a <code>ptr_mode</code> value from the memory
|
|
in operand 1 to the memory in operand 0 without leaving the value in
|
|
a register afterward. This is to avoid leaking the value some place
|
|
that an attacker might use to rewrite the stack guard slot after
|
|
having clobbered it.
|
|
</p>
|
|
<p>If this pattern is not defined, then a plain move pattern is generated.
|
|
</p>
|
|
<a name="index-stack_005fprotect_005ftest-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>stack_protect_test</samp>’</dt>
|
|
<dd><p>This pattern, if defined, compares a <code>ptr_mode</code> value from the
|
|
memory in operand 1 with the memory in operand 0 without leaving the
|
|
value in a register afterward and branches to operand 2 if the values
|
|
were equal.
|
|
</p>
|
|
<p>If this pattern is not defined, then a plain compare pattern and
|
|
conditional branch pattern is used.
|
|
</p>
|
|
<a name="index-clear_005fcache-instruction-pattern"></a>
|
|
</dd>
|
|
<dt>‘<samp>clear_cache</samp>’</dt>
|
|
<dd><p>This pattern, if defined, flushes the instruction cache for a region of
|
|
memory. The region is bounded to by the Pmode pointers in operand 0
|
|
inclusive and operand 1 exclusive.
|
|
</p>
|
|
<p>If this pattern is not defined, a call to the library function
|
|
<code>__clear_cache</code> is used.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
<hr>
|
|
<div class="header">
|
|
<p>
|
|
Next: <a href="Pattern-Ordering.html#Pattern-Ordering" accesskey="n" rel="next">Pattern Ordering</a>, Previous: <a href="Constraints.html#Constraints" accesskey="p" rel="prev">Constraints</a>, Up: <a href="Machine-Desc.html#Machine-Desc" accesskey="u" rel="up">Machine Desc</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
|
|
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|
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|
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