[PATCH] D28405: SimplifyLibCalls: Replace fabs libcalls with intrinsics

[Eli Friedman via Phabricator via llvm-commits]

efriedma added a comment.

I'd still like to see a test which checks the transform fabsl() -> llvm.fabs.f80().



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Comment at: lib/Transforms/InstCombine/InstCombineCalls.cpp:1644
+                                           { ExtSrc->getType() });
+      Value *NewFabs = Builder->CreateCall(F, ExtSrc);
+      NewFabs->takeName(II);
----------------
Fast-math flags?


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Comment at: test/Transforms/InstCombine/fabs.ll:16
 ; CHECK-NEXT: %mul = fmul float %x, %x
-; CHECK-NEXT: %fabsf = tail call float @fabsf(float %mul)
+; CHECK-NEXT: %fabsf = call float @llvm.fabs.f32(float %mul)
 ; CHECK-NEXT: ret float %fabsf
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efriedma wrote:
> This is probably going to fail on Windows... maybe change the test to call llvm.fabs rather than fabs?
Still probably going to fail on Windows, where fabsf() doesn't exist.


https://reviews.llvm.org/D28405