InstCombine: fold fcmp (fneg x), (fneg y) -> fcmp x, y
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128627 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/InstCombine/InstCombineCompares.cpp b/lib/Transforms/InstCombine/InstCombineCompares.cpp
index 6743885..cb434bd 100644
--- a/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -2855,6 +2855,11 @@
}
}
+ // fcmp (fneg x), (fneg y) -> fcmp x, y
+ Value *X, *Y;
+ if (match(Op0, m_FNeg(m_Value(X))) && match(Op1, m_FNeg(m_Value(Y))))
+ return new FCmpInst(I.getPredicate(), X, Y);
+
// fcmp (fpext x), (fpext y) -> fcmp x, y
if (FPExtInst *LHSExt = dyn_cast<FPExtInst>(Op0))
if (FPExtInst *RHSExt = dyn_cast<FPExtInst>(Op1))
diff --git a/test/Transforms/InstCombine/fcmp.ll b/test/Transforms/InstCombine/fcmp.ll
index f869a18..66607ea 100644
--- a/test/Transforms/InstCombine/fcmp.ll
+++ b/test/Transforms/InstCombine/fcmp.ll
@@ -40,3 +40,12 @@
; CHECK: @test5
; CHECK-NEXT: fcmp olt float %a, -1.0
}
+
+define i1 @test6(float %x, float %y) nounwind {
+ %neg1 = fsub float -0.000000e+00, %x
+ %neg2 = fsub float -0.000000e+00, %y
+ %cmp = fcmp ogt float %neg1, %neg2
+ ret i1 %cmp
+; CHECK: @test6
+; CHECK-NEXT: fcmp ogt float %x, %y
+}