Fix the folding of floating-point math library calls, like sin(infinity),

so that it detects errors on platforms where libm doesn't set errno.
It's still subject to host libm details though.

llvm-svn: 114148

1 files changed, 19 insertions, 0 deletions

diff --git a/llvm/test/Transforms/InstCombine/fold-calls.ll b/llvm/test/Transforms/InstCombine/fold-calls.ll
new file mode 100644
index 00000000000..2b11771969f
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/fold-calls.ll
@@ -0,0 +1,19 @@
+; RUN: opt -instcombine -S < %s | FileCheck %s
+
+; This shouldn't fold, because sin(inf) is invalid.
+; CHECK: @foo
+; CHECK:   %t = call double @sin(double 0x7FF0000000000000)
+define double @foo() {
+  %t = call double @sin(double 0x7FF0000000000000)
+  ret double %t
+}
+
+; This should fold.
+; CHECK: @bar
+; CHECK:   ret double 0x3FDA6026360C2F91
+define double @bar() {
+  %t = call double @sin(double 9.0)
+  ret double %t
+}
+
+declare double @sin(double)