clang/test/CodeGenCXX/cxx1z-copy-omission.cpp

   1 // RUN: %clang_cc1 -std=c++1z -emit-llvm -triple x86_64-linux-gnu -o - %s | FileCheck %s
   2
   3 struct A {
   4   A(int);
   5   A(A&&);
   6   A(const A&);
   7   ~A();
   8
   9   operator bool();
  10
  11   int arr[10];
  12 };
  13
  14 A f();
  15 void h();
  16
  17 // CHECK-LABEL: define {{.*}} @_Z1gv(
  18 void g() {
  19   // CHECK: %[[A:.*]] = alloca
  20   // CHECK-NOT: alloca
  21   // CHECK-NOT: call
  22   // CHECK: call {{.*}} @_Z1fv(ptr sret({{.*}}) align 4 %[[A]])
  23   A a = A( A{ f() } );
  24   // CHECK-NOT: call
  25
  26   // CHECK: call void @_Z1hv(
  27   h();
  28   // CHECK-NOT: call
  29
  30   // CHECK: call void @_ZN1AD1Ev(ptr {{[^,]*}} %[[A]])
  31   // CHECK-NOT: call
  32   // CHECK-LABEL: }
  33 }
  34
  35 void f(A);
  36
  37 // CHECK-LABEL: define {{.*}} @_Z1hv(
  38 void h() {
  39   // CHECK: %[[A:.*]] = alloca
  40   // CHECK-NOT: alloca
  41   // CHECK-NOT: call
  42
  43   // CHECK: call {{.*}} @_Z1fv(ptr sret({{.*}}) align 4 %[[A]])
  44   // CHECK-NOT: call
  45   // CHECK: call {{.*}} @_Z1f1A(ptr noundef %[[A]])
  46   f(f());
  47   // CHECK-NOT: call
  48   // CHECK: call void @_ZN1AD1Ev(ptr {{[^,]*}} %[[A]])
  49
  50   // CHECK: call void @_Z1hv(
  51   h();
  52
  53   // CHECK-NOT: call
  54   // CHECK-LABEL: }
  55 }
  56
  57 // We still pass classes with trivial copy/move constructors and destructors in
  58 // registers, even if the copy is formally omitted.
  59 struct B {
  60   B(int);
  61   int n;
  62 };
  63
  64 B fB();
  65 void fB(B);
  66
  67 // CHECK-LABEL: define {{.*}} @_Z1iv(
  68 void i() {
  69   // CHECK: %[[B:.*]] = alloca
  70   // CHECK-NOT: alloca
  71   // CHECK-NOT: call
  72
  73   // CHECK: %[[B_N:.*]] = call i32 @_Z2fBv()
  74   // CHECK-NOT: call
  75   // CHECK: store i32 %[[B_N]],
  76   // CHECK-NOT: call
  77   // CHECK: %[[B_N:.*]] = load i32
  78   // CHECK-NOT: call
  79   // CHECK: call void @_Z2fB1B(i32 %[[B_N]])
  80   fB(fB());
  81
  82   // CHECK-LABEL: }
  83 }
  84
  85 // CHECK-LABEL: define {{.*}} @_Z1jv(
  86 void j() {
  87   // CHECK:   alloca ptr
  88   // CHECK:   %[[OUTERTEMP:.*]] = alloca %{{.*}}
  89   // CHECK:   %[[INNERTEMP:.*]] = alloca %{{.*}}
  90   // CHECK:   call void @_ZN1AC1Ei(ptr {{.*}} %[[INNERTEMP]], i32 noundef 1)
  91   // CHECK:   call noundef zeroext i1 @_ZN1AcvbEv(ptr {{.*}} %[[INNERTEMP]])
  92   // CHECK:   br i1
  93   //
  94   // CHECK:   call void @_ZN1AC1EOS_(ptr {{.*}} %[[OUTERTEMP]], ptr {{.*}} %[[INNERTEMP]])
  95   // CHECK:   br label
  96   //
  97   // CHECK:   call void @_ZN1AC1Ei(ptr {{.*}} %[[OUTERTEMP]], i32 noundef 2)
  98   // CHECK:   br label
  99   //
 100   // CHECK:   call void @_ZN1AD1Ev(ptr {{.*}} %[[INNERTEMP]])
 101   A &&a = A(1) ?: A(2);
 102
 103   // CHECK:   call void @_Z1iv()
 104   i();
 105
 106   // CHECK:   call void @_ZN1AD1Ev(ptr {{.*}} %[[OUTERTEMP]])
 107 }