The frexp, modf, and remquo builtins are not 'const'.

These functions return a second value by writing to a pointer argument,
so they cannot be marked 'readnone' which implies that they don't access
memory.

<rdar://problem/10070234>

llvm-svn: 139319

1 files changed, 41 insertions, 0 deletions

diff --git a/clang/test/CodeGen/builtin-attributes.c b/clang/test/CodeGen/builtin-attributes.c
index 822b8eecf7d..3781eba2669 100644
--- a/clang/test/CodeGen/builtin-attributes.c
+++ b/clang/test/CodeGen/builtin-attributes.c
@@ -15,3 +15,44 @@ void f1() {
 char* f2(char* a, char* b) {
   return __builtin_strstr(a, b);
 }
+
+// frexp is NOT readnone. It writes to its pointer argument.
+// <rdar://problem/10070234>
+//
+// CHECK: f3
+// CHECK: call double @frexp(double %
+// CHECK-NOT: readnone
+// CHECK: call float @frexpf(float %
+// CHECK-NOT: readnone
+// CHECK: call double @frexpl(double %
+// CHECK-NOT: readnone
+//
+// Same thing for modf and friends.
+//
+// CHECK: call double @modf(double %
+// CHECK-NOT: readnone
+// CHECK: call float @modff(float %
+// CHECK-NOT: readnone
+// CHECK: call double @modfl(double %
+// CHECK-NOT: readnone
+//
+// CHECK: call double @remquo(double %
+// CHECK-NOT: readnone
+// CHECK: call float @remquof(float %
+// CHECK-NOT: readnone
+// CHECK: call double @remquol(double %
+// CHECK-NOT: readnone
+// CHECK: ret
+int f3(double x) {
+  int e;
+  __builtin_frexp(x, &e);
+  __builtin_frexpf(x, &e);
+  __builtin_frexpl(x, &e);
+  __builtin_modf(x, &e);
+  __builtin_modff(x, &e);
+  __builtin_modfl(x, &e);
+  __builtin_remquo(x, x, &e);
+  __builtin_remquof(x, x, &e);
+  __builtin_remquol(x, x, &e);
+  return e;
+}