[CodeGen] fix const-ness of cbrt and fma

cbrt() is always constant because it can't overflow or underflow. Therefore, it can't set errno.

fma() is not always constant because it can overflow or underflow. Therefore, it can set errno.
But we know that it never sets errno on GNU / MSVC, so make it constant in those environments.

Differential Revision: https://reviews.llvm.org/D39641

llvm-svn: 318093

1 files changed, 22 insertions, 6 deletions

diff --git a/clang/test/CodeGen/math-builtins.c b/clang/test/CodeGen/math-builtins.c
index cb9b5974584..fb494f2e1f5 100644
--- a/clang/test/CodeGen/math-builtins.c
+++ b/clang/test/CodeGen/math-builtins.c
@@ -1,5 +1,7 @@
 // RUN: %clang_cc1 -triple x86_64-unknown-unknown -w -S -o - -emit-llvm              %s | FileCheck %s -check-prefix=NO__ERRNO
 // RUN: %clang_cc1 -triple x86_64-unknown-unknown -w -S -o - -emit-llvm -fmath-errno %s | FileCheck %s -check-prefix=HAS_ERRNO
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown-gnu -w -S -o - -emit-llvm -fmath-errno %s | FileCheck %s --check-prefix=HAS_ERRNO_GNU
+// RUN: %clang_cc1 -triple x86_64-unknown-windows-msvc -w -S -o - -emit-llvm -fmath-errno %s | FileCheck %s --check-prefix=HAS_ERRNO_WIN
 
 // Test attributes and codegen of math builtins.
 
@@ -175,9 +177,9 @@ void foo(double *d, float f, float *fp, long double *l, int *i, const char *c) {
 // NO__ERRNO: declare double @cbrt(double) [[READNONE]]
 // NO__ERRNO: declare float @cbrtf(float) [[READNONE]]
 // NO__ERRNO: declare x86_fp80 @cbrtl(x86_fp80) [[READNONE]]
-// HAS_ERRNO: declare double @cbrt(double) [[NOT_READNONE]]
-// HAS_ERRNO: declare float @cbrtf(float) [[NOT_READNONE]]
-// HAS_ERRNO: declare x86_fp80 @cbrtl(x86_fp80) [[NOT_READNONE]]
+// HAS_ERRNO: declare double @cbrt(double) [[READNONE]]
+// HAS_ERRNO: declare float @cbrtf(float) [[READNONE]]
+// HAS_ERRNO: declare x86_fp80 @cbrtl(x86_fp80) [[READNONE]]
 
   __builtin_ceil(f);       __builtin_ceilf(f);      __builtin_ceill(f);
 
@@ -274,9 +276,20 @@ void foo(double *d, float f, float *fp, long double *l, int *i, const char *c) {
 // NO__ERRNO: declare double @llvm.fma.f64(double, double, double) [[READNONE_INTRINSIC]]
 // NO__ERRNO: declare float @llvm.fma.f32(float, float, float) [[READNONE_INTRINSIC]]
 // NO__ERRNO: declare x86_fp80 @llvm.fma.f80(x86_fp80, x86_fp80, x86_fp80) [[READNONE_INTRINSIC]]
-// HAS_ERRNO: declare double @llvm.fma.f64(double, double, double) [[READNONE_INTRINSIC]]
-// HAS_ERRNO: declare float @llvm.fma.f32(float, float, float) [[READNONE_INTRINSIC]]
-// HAS_ERRNO: declare x86_fp80 @llvm.fma.f80(x86_fp80, x86_fp80, x86_fp80) [[READNONE_INTRINSIC]]
+// HAS_ERRNO: declare double @fma(double, double, double) [[NOT_READNONE]]
+// HAS_ERRNO: declare float @fmaf(float, float, float) [[NOT_READNONE]]
+// HAS_ERRNO: declare x86_fp80 @fmal(x86_fp80, x86_fp80, x86_fp80) [[NOT_READNONE]]
+
+// On GNU or Win, fma never sets errno, so we can convert to the intrinsic.
+
+// HAS_ERRNO_GNU: declare double @llvm.fma.f64(double, double, double) [[READNONE_INTRINSIC:#[0-9]+]]
+// HAS_ERRNO_GNU: declare float @llvm.fma.f32(float, float, float) [[READNONE_INTRINSIC]]
+// HAS_ERRNO_GNU: declare x86_fp80 @llvm.fma.f80(x86_fp80, x86_fp80, x86_fp80) [[READNONE_INTRINSIC]]
+
+// HAS_ERRNO_WIN: declare double @llvm.fma.f64(double, double, double) [[READNONE_INTRINSIC:#[0-9]+]]
+// HAS_ERRNO_WIN: declare float @llvm.fma.f32(float, float, float) [[READNONE_INTRINSIC]]
+// Long double is just double on win, so no f80 use/declaration.
+// HAS_ERRNO_WIN-NOT: declare x86_fp80 @llvm.fma.f80(x86_fp80, x86_fp80, x86_fp80)
 
   __builtin_fmax(f,f);       __builtin_fmaxf(f,f);      __builtin_fmaxl(f,f);
 
@@ -558,3 +571,6 @@ void foo(double *d, float f, float *fp, long double *l, int *i, const char *c) {
 // HAS_ERRNO: attributes [[READNONE_INTRINSIC]] = { {{.*}}readnone{{.*}} }
 // HAS_ERRNO: attributes [[READNONE]] = { {{.*}}readnone{{.*}} }
 
+// HAS_ERRNO_GNU: attributes [[READNONE_INTRINSIC]] = { {{.*}}readnone{{.*}} }
+// HAS_ERRNO_WIN: attributes [[READNONE_INTRINSIC]] = { {{.*}}readnone{{.*}} }
+