[PATCH] D137811: InstCombine: Port amdgcn.class intrinsic combines to is.fpclass

[Serge Pavlov via Phabricator via llvm-commits]

sepavloff added inline comments.


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Comment at: llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp:824
+    // Equivalent of isnan. Replace with standard fcmp.
+    Value *FCmp = Builder.CreateFCmpUNO(Src0, Src0);
+    FCmp->takeName(&II);
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Is it profitable to make such replacement early? Is there any advantage, at least hypothetical? 


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Comment at: llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp:846-850
+#if 0
+    if (isa<UndefValue>(Src0)) {
+      return replaceInstUsesWith(II, UndefValue::get(II.getType()));
+    }
+#endif
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Deleted code?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D137811/new/

https://reviews.llvm.org/D137811