llvm-project/clang/test/CodeGenCXX/copy-constructor-elim-2.cpp

97 lines
2.4 KiB
C++

// RUN: %clang_cc1 -triple armv7-none-eabi -emit-llvm -o - %s | FileCheck %s
struct A { int x; A(int); ~A(); };
A f() { return A(0); }
// CHECK-LABEL: define void @_Z1fv
// CHECK: call {{.*}} @_ZN1AC1Ei
// CHECK-NEXT: ret void
// Verify that we do not elide copies when constructing a base class.
namespace no_elide_base {
struct Base {
Base(const Base&);
~Base();
};
struct Other {
operator Base() const;
};
struct Derived : public virtual Base {
Derived(const Other &O);
};
// CHECK: define {{.*}} @_ZN13no_elide_base7DerivedC1ERKNS_5OtherE(%"struct.no_elide_base::Derived"* returned %this, %"struct.no_elide_base::Other"* dereferenceable({{[0-9]+}}) %O) unnamed_addr
Derived::Derived(const Other &O)
// CHECK: call {{.*}} @_ZNK13no_elide_base5OthercvNS_4BaseEEv
// CHECK: call {{.*}} @_ZN13no_elide_base4BaseC2ERKS0_
// CHECK: call {{.*}} @_ZN13no_elide_base4BaseD1Ev
: Base(O)
{
// CHECK: ret
}
}
// PR8683.
namespace PR8683 {
struct A {
A();
A(const A&);
A& operator=(const A&);
};
struct B {
A a;
};
void f() {
// Verify that we don't mark the copy constructor in this expression as elidable.
// CHECK: call {{.*}} @_ZN6PR86831AC1ERKS0_
A a = (B().a);
}
}
namespace PR12139 {
struct A {
A() : value(1) { }
A(A const &, int value = 2) : value(value) { }
int value;
static A makeA() { A a; a.value = 2; return a; }
};
// CHECK-LABEL: define i32 @_ZN7PR121394testEv
int test() {
// CHECK: call void @_ZN7PR121391A5makeAEv
// CHECK-NEXT: call %"struct.PR12139::A"* @_ZN7PR121391AC1ERKS0_i
A a(A::makeA(), 3);
// CHECK-NEXT: getelementptr inbounds
// CHECK-NEXT: load
// CHECK-NEXT: ret i32
return a.value;
}
}
namespace ElidableCallIsNotCopyCtor {
struct A { A(const A&); };
struct B : A {
B(B&);
B(A);
B(int);
};
void f() {
// Here, we construct via B(int) then B(A). The B(A) construction is
// elidable, but we don't have an AST representation for the case where we
// must elide not only a constructor call but also some argument
// conversions, so we don't elide it.
// CHECK-LABEL: define void @_ZN25ElidableCallIsNotCopyCtor1fEv(
// CHECK: call {{.*}} @_ZN25ElidableCallIsNotCopyCtor1BC1Ei(
// CHECK: call {{.*}} @_ZN25ElidableCallIsNotCopyCtor1AC1ERKS0_(
// CHECK: call {{.*}} @_ZN25ElidableCallIsNotCopyCtor1BC1ENS_1AE(
B b = 0;
}
}