mirror of
https://github.com/llvm/llvm-project.git
synced 2025-04-28 03:16:05 +00:00
122f88d481
When an object of class type is initialized from a prvalue of the same type (ignoring cv qualifications), use the prvalue to initialize the object directly instead of inserting a redundant elidable call to a copy constructor. llvm-svn: 288866
82 lines
1.5 KiB
C++
82 lines
1.5 KiB
C++
// 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();
|
|
|
|
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: }
|
|
}
|