[PATCH] D109949: [x86][AMX] Support undef and zeroinitializer for x86_amx

[Xiang Zhang via Phabricator via llvm-commits]

xiangzhangllvm added inline comments.


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Comment at: llvm/lib/IR/Verifier.cpp:4603-4606
     if (auto *Const = dyn_cast<Constant>(V))
-      Assert(!Const->getType()->isX86_AMXTy(),
+      Assert(!(Const->getType()->isX86_AMXTy() && !Const->isNullValue() &&
+               !isa<UndefValue>(V)),
              "const x86_amx is not allowed in argument!");
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I think we can remove this code, it is strange here.


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Comment at: llvm/lib/Target/X86/X86LowerAMXType.cpp:308
       Instruction &Inst = *II++;
+      // handle with amx_type of undef and zeroinitializer
+      if (auto *Intr = dyn_cast<IntrinsicInst>(&Inst)) {
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This way is finding which operand is amx null/undef, then create a tilezero to replace the operand.
here may be create a lot of tilezeros.

I think here must be a better way to do it. 

e.g. From the value side, replace all of uses of it.



Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D109949/new/

https://reviews.llvm.org/D109949