[PATCH] D144154: [X86]Use Class to refactor ArithMetic td file in X86

Wed Feb 15 18:57:42 PST 2023

skan added inline comments.

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Comment at: llvm/lib/Target/X86/X86InstrArithmetic.td:741
+let Defs = [AX,DX,EFLAGS], Uses = [AX] in
+def IMUL16r : MulOpR<0xF7, MRM5r, "imul", Xi16, WriteIMul16, []>;
+// EAX,EDX = EAX*GR32
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XinWang10 wrote:
> skan wrote:
> > Could we define `MulOpR` as a multiclass and use `defm IMUL`?
> I don't know if it is necessary? In my understanding, class and multiclass is designed for reuse, but if I rewrite a MulOpR as a multiclass here for IMUL, seems it has only one user here?
> 
What's difference? You already define class `MulOpR` for MUL and IMUL, and if we change it to multiclass, couldn't we use it for MUL and IMUL as well? And the suffix "8r", "16r", "32r", "64r" can be written only once.

Repository:
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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D144154/new/

https://reviews.llvm.org/D144154