Files
clang-p2996/clang/test/CodeGenCXX/builtin-bit-cast-no-tbaa.cpp
Richard Smith 74ce7112c3 Fix behavior of __builtin_bit_cast when the From and To types are the
same.

We were missing the lvalue-to-rvalue conversion entirely in this case,
and in fact still need the full CK_LValueToRValueBitCast conversion to
perform a load with no TBAA.

llvm-svn: 373874
2019-10-07 02:45:12 +00:00

25 lines
787 B
C++

// RUN: %clang_cc1 -O3 -std=c++2a -S -emit-llvm -o - -disable-llvm-passes -triple x86_64-apple-macos10.14 %s | FileCheck %s
void test_scalar() {
// CHECK-LABEL: define void @_Z11test_scalarv
__builtin_bit_cast(float, 42);
// CHECK: load float, float* {{.*}}, align 4, !tbaa ![[MAY_ALIAS_TBAA:.*]]
}
void test_scalar2() {
// CHECK-LABEL: define void @_Z12test_scalar2v
struct S {int m;};
__builtin_bit_cast(int, S{42});
// CHECK: load i32, i32* {{.*}}, align 4, !tbaa ![[MAY_ALIAS_TBAA]]
}
int test_same_type(int &r) {
// CHECK: load i32, i32* {{.*}}, align 4, !tbaa ![[MAY_ALIAS_TBAA]]
return __builtin_bit_cast(int, r);
}
// CHECK: ![[CHAR_TBAA:.*]] = !{!"omnipotent char", {{.*}}, i64 0}
// CHECK: ![[MAY_ALIAS_TBAA]] = !{![[CHAR_TBAA]], ![[CHAR_TBAA]], i64 0}