[PATCH] D157717: [X86][Codegen] Remove dead code for ADCX/ADOX

[Kan Shengchen via Phabricator via llvm-commits]

skan marked 2 inline comments as done.
skan added inline comments.


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Comment at: llvm/lib/Target/X86/X86InstrArithmetic.td:1377
 
-let Predicates = [HasADX], Defs = [EFLAGS], Uses = [EFLAGS],
-    Constraints = "$src1 = $dst", hasSideEffects = 0 in {
+let Defs = [EFLAGS], Uses = [EFLAGS], Constraints = "$src1 = $dst", hasSideEffects = 0 in {
   let SchedRW = [WriteADC], isCommutable = 1 in {
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craig.topper wrote:
> skan wrote:
> > craig.topper wrote:
> > > Why delete the predcate?
> > Except assembler predicate like `In64BitMode`, a predicate only has effect when the pattern is not empty.
> > There is no pattern for ADCX/ADOX, so I remove the pattern. 
> I thought it could be used by https://reviews.llvm.org/D148516 that can use it to filter illegal instructions from llvm-exegesis testing. But I guess that uses the AssemblerPredicate so only filters In64BitMode. That seems kind of broken for its intended usage.
I see. It seems that you prefer to keep the predicate. Let me revert the change in this file. 


Repository:
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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D157717/new/

https://reviews.llvm.org/D157717