[llvm-commits] [llvm] r163035 - in /llvm/trunk: lib/Target/X86/X86InstrFMA.td lib/Target/X86/X86InstrInfo.cpp test/CodeGen/X86/fma_patterns.ll

[Jakob Stoklund Olesen]

On Aug 31, 2012, at 4:10 PM, Craig Topper <craig.topper at gmail.com> wrote:

> Author: ctopper
> Date: Fri Aug 31 18:10:34 2012
> New Revision: 163035
> 
> URL: http://llvm.org/viewvc/llvm-project?rev=163035&view=rev
> Log:
> Mark FMA4 instructions as commutable and add them to the folding tables.
> 

> multiclass fma4s<bits<8> opc, string OpcodeStr, RegisterClass RC,
>                  X86MemOperand x86memop, ValueType OpVT, SDNode OpNode,
>                  PatFrag mem_frag> {
> +  let isCommutable = 1 in
>   def rr : FMA4<opc, MRMSrcReg, (outs RC:$dst),
>            (ins RC:$src1, RC:$src2, RC:$src3),
>            !strconcat(OpcodeStr,

Hi Craig,

I am not sure it is safe to mark 3-input instructions as commutable. See TargetInstrInfoImpl::findCommutedOpIndices().

Why do you need to do that?

/jakob