LLVM currently represents floating-point negation as -0.0 - x. Fix
FastISel to recognize this pattern and emit a floating-point
negation using xor.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80963 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGen/X86/fast-isel-fneg.ll b/test/CodeGen/X86/fast-isel-fneg.ll
new file mode 100644
index 0000000..41b288b
--- /dev/null
+++ b/test/CodeGen/X86/fast-isel-fneg.ll
@@ -0,0 +1,15 @@
+; RUN: llvm-as < %s | llc -fast-isel -march=x86-64 | FileCheck %s
+
+; CHECK: doo:
+; CHECK: xorpd
+define double @doo(double %x) nounwind {
+ %y = fsub double -0.0, %x
+ ret double %y
+}
+
+; CHECK: foo:
+; CHECK: xorps
+define float @foo(float %x) nounwind {
+ %y = fsub float -0.0, %x
+ ret float %y
+}