Imported Upstream version 6.0.0.172

Former-commit-id: f3cc9b82f3e5bd8f0fd3ebc098f789556b44e9cd

external/llvm/test/Transforms/InstCombine/constant-fold-libfunc.ll

@@ -0,0 +1,31 @@
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+declare double @acos(double)
+
+; Check that functions without any function attributes are simplified.
+
+define double @test_simplify_acos() {
+; CHECK-LABEL: @test_simplify_acos
+  %pi = call double @acos(double -1.000000e+00)
+; CHECK-NOT: call double @acos
+; CHECK: ret double 0x400921FB54442D18
+  ret double %pi
+}
+
+; Check that we don't constant fold builtin functions.
+
+define double @test_acos_nobuiltin() {
+; CHECK-LABEL: @test_acos_nobuiltin
+  %pi = call double @acos(double -1.000000e+00) nobuiltin 
+; CHECK: call double @acos(double -1.000000e+00)
+  ret double %pi
+}
+
+; Check that we don't constant fold strictfp results that require rounding.
+
+define double @test_acos_strictfp() {
+; CHECK-LABEL: @test_acos_strictfp
+  %pi = call double @acos(double -1.000000e+00) strictfp 
+; CHECK: call double @acos(double -1.000000e+00)
+  ret double %pi
+}