[InstSimplify] sqrt(X) * sqrt(X) --> X

This was misplaced in InstCombine. We can loosen the FMF as a follow-up step.

llvm-svn: 325965

2 files changed, 15 insertions, 11 deletions

diff --git a/llvm/test/Transforms/InstCombine/fmul.ll b/llvm/test/Transforms/InstCombine/fmul.ll
index 1c05475ba07..2eaa7c3e761 100644
--- a/llvm/test/Transforms/InstCombine/fmul.ll
+++ b/llvm/test/Transforms/InstCombine/fmul.ll
@@ -172,19 +172,8 @@ define float @test11(float %x, float %y) {
   ret float %c
 }
 
-; PR21126: http://llvm.org/bugs/show_bug.cgi?id=21126
-; With unsafe/fast math, sqrt(X) * sqrt(X) is just X.
 declare double @llvm.sqrt.f64(double)
 
-define double @sqrt_squared1(double %f) {
-; CHECK-LABEL: @sqrt_squared1(
-; CHECK-NEXT:    ret double [[F:%.*]]
-;
-  %sqrt = call double @llvm.sqrt.f64(double %f)
-  %mul = fmul fast double %sqrt, %sqrt
-  ret double %mul
-}
-
 ; With unsafe/fast math, sqrt(X) * sqrt(X) is just X,
 ; but make sure another use of the sqrt is intact.
 ; Note that the remaining fmul is altered but is not 'fast'
diff --git a/llvm/test/Transforms/InstSimplify/fast-math.ll b/llvm/test/Transforms/InstSimplify/fast-math.ll
index f4f31236e5c..dbf17a2fcee 100644
--- a/llvm/test/Transforms/InstSimplify/fast-math.ll
+++ b/llvm/test/Transforms/InstSimplify/fast-math.ll
@@ -203,3 +203,18 @@ define float @fdiv_neg_swapped2(float %f) {
   %div = fdiv nnan float %f, %neg
   ret float %div
 }
+
+; PR21126: http://llvm.org/bugs/show_bug.cgi?id=21126
+; With unsafe/fast math, sqrt(X) * sqrt(X) is just X.
+
+declare double @llvm.sqrt.f64(double)
+
+define double @sqrt_squared(double %f) {
+; CHECK-LABEL: @sqrt_squared(
+; CHECK-NEXT:    ret double [[F:%.*]]
+;
+  %sqrt = call double @llvm.sqrt.f64(double %f)
+  %mul = fmul fast double %sqrt, %sqrt
+  ret double %mul
+}
+