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| // RUN: %clang_cc1 -std=c++1z -emit-llvm -triple x86_64-linux-gnu -o - %s | FileCheck %s
struct A {
A(int);
A(A&&);
A(const A&);
~A();
operator bool();
int arr[10];
};
A f();
void h();
// CHECK-LABEL: define {{.*}} @_Z1gv(
void g() {
// CHECK: %[[A:.*]] = alloca
// CHECK-NOT: alloca
// CHECK-NOT: call
// CHECK: call {{.*}} @_Z1fv({{.*}}* sret %[[A]])
A a = A( A{ f() } );
// CHECK-NOT: call
// CHECK: call void @_Z1hv(
h();
// CHECK-NOT: call
// CHECK: call void @_ZN1AD1Ev({{.*}}* %[[A]])
// CHECK-NOT: call
// CHECK-LABEL: }
}
void f(A);
// CHECK-LABEL: define {{.*}} @_Z1hv(
void h() {
// CHECK: %[[A:.*]] = alloca
// CHECK-NOT: alloca
// CHECK-NOT: call
// CHECK: call {{.*}} @_Z1fv({{.*}}* sret %[[A]])
// CHECK-NOT: call
// CHECK: call {{.*}} @_Z1f1A({{.*}}* %[[A]])
f(f());
// CHECK-NOT: call
// CHECK: call void @_ZN1AD1Ev({{.*}}* %[[A]])
// CHECK: call void @_Z1hv(
h();
// CHECK-NOT: call
// CHECK-LABEL: }
}
// We still pass classes with trivial copy/move constructors and destructors in
// registers, even if the copy is formally omitted.
struct B {
B(int);
int n;
};
B fB();
void fB(B);
// CHECK-LABEL: define {{.*}} @_Z1iv(
void i() {
// CHECK: %[[B:.*]] = alloca
// CHECK-NOT: alloca
// CHECK-NOT: call
// CHECK: %[[B_N:.*]] = call i32 @_Z2fBv()
// CHECK-NOT: call
// CHECK: store i32 %[[B_N]],
// CHECK-NOT: call
// CHECK: %[[B_N:.*]] = load i32
// CHECK-NOT: call
// CHECK: call void @_Z2fB1B(i32 %[[B_N]])
fB(fB());
// CHECK-LABEL: }
}
// CHECK-LABEL: define {{.*}} @_Z1jv(
void j() {
// CHECK: alloca %{{.*}}*
// CHECK: %[[OUTERTEMP:.*]] = alloca %{{.*}}
// CHECK: %[[INNERTEMP:.*]] = alloca %{{.*}}
// CHECK: call void @_ZN1AC1Ei(%{{.*}} %[[INNERTEMP]], i32 1)
// CHECK: call zeroext i1 @_ZN1AcvbEv(%{{.*}} %[[INNERTEMP]])
// CHECK: br i1
//
// CHECK: call void @_ZN1AC1EOS_(%{{.*}} %[[OUTERTEMP]], %{{.*}} %[[INNERTEMP]])
// CHECK: br label
//
// CHECK: call void @_ZN1AC1Ei(%{{.*}} %[[OUTERTEMP]], i32 2)
// CHECK: br label
//
// CHECK: call void @_ZN1AD1Ev(%{{.*}} %[[INNERTEMP]])
A &&a = A(1) ?: A(2);
// CHECK: call void @_Z1iv()
i();
// CHECK: call void @_ZN1AD1Ev(%{{.*}} %[[OUTERTEMP]])
}
|