clang/test/CodeGenCXX/builtin-bit-cast.cpp

   1 // RUN: %clang_cc1 -std=c++2a -emit-llvm -o - -disable-llvm-passes -triple x86_64-apple-macos10.14 %s | FileCheck %s
   2
   3 void test_scalar(int &oper) {
   4   // CHECK-LABEL: define{{.*}} void @_Z11test_scalarRi
   5   __builtin_bit_cast(float, oper);
   6
   7   // CHECK: [[OPER:%.*]] = alloca ptr
   8   // CHECK: [[REF:%.*]] = load ptr, ptr
   9   // CHECK-NEXT: load float, ptr [[REF]]
  10 }
  11
  12 struct two_ints {
  13   int x;
  14   int y;
  15 };
  16
  17 unsigned long test_aggregate_to_scalar(two_ints &ti) {
  18   // CHECK-LABEL: define{{.*}} i64 @_Z24test_aggregate_to_scalarR8two_ints
  19   return __builtin_bit_cast(unsigned long, ti);
  20
  21   // CHECK: [[TI_ADDR:%.*]] = alloca ptr, align 8
  22   // CHECK: [[TI_LOAD:%.*]] = load ptr, ptr [[TI_ADDR]]
  23   // CHECK-NEXT: load i64, ptr [[TI_LOAD]]
  24 }
  25
  26 struct two_floats {
  27   float x;
  28   float y;
  29 };
  30
  31 two_floats test_aggregate_record(two_ints& ti) {
  32   // CHECK-LABEL: define{{.*}} <2 x float> @_Z21test_aggregate_recordR8two_int
  33    return __builtin_bit_cast(two_floats, ti);
  34
  35   // CHECK: [[RETVAL:%.*]] = alloca %struct.two_floats, align 4
  36   // CHECK: [[TI:%.*]] = alloca ptr, align 8
  37
  38   // CHECK: [[LOAD_TI:%.*]] = load ptr, ptr [[TI]]
  39   // CHECK: call void @llvm.memcpy.p0.p0.i64(ptr align 4 [[RETVAL]], ptr align 4 [[LOAD_TI]]
  40 }
  41
  42 two_floats test_aggregate_array(int (&ary)[2]) {
  43   // CHECK-LABEL: define{{.*}} <2 x float> @_Z20test_aggregate_arrayRA2_i
  44   return __builtin_bit_cast(two_floats, ary);
  45
  46   // CHECK: [[RETVAL:%.*]] = alloca %struct.two_floats, align 4
  47   // CHECK: [[ARY:%.*]] = alloca ptr, align 8
  48
  49   // CHECK: [[LOAD_ARY:%.*]] = load ptr, ptr [[ARY]]
  50   // CHECK: call void @llvm.memcpy.p0.p0.i64(ptr align 4 [[RETVAL]], ptr align 4 [[LOAD_ARY]]
  51 }
  52
  53 two_ints test_scalar_to_aggregate(unsigned long ul) {
  54   // CHECK-LABEL: define{{.*}} i64 @_Z24test_scalar_to_aggregatem
  55   return __builtin_bit_cast(two_ints, ul);
  56
  57   // CHECK: [[TI:%.*]] = alloca %struct.two_ints, align 4
  58   // CHECK: call void @llvm.memcpy.p0.p0.i64(ptr align 4 [[TI]]
  59 }
  60
  61 unsigned long test_complex(_Complex unsigned &cu) {
  62   // CHECK-LABEL: define{{.*}} i64 @_Z12test_complexRCj
  63   return __builtin_bit_cast(unsigned long, cu);
  64
  65   // CHECK: [[REF_ALLOCA:%.*]] = alloca ptr, align 8
  66   // CHECK-NEXT: store ptr {{.*}}, ptr [[REF_ALLOCA]]
  67   // CHECK-NEXT: [[REF:%.*]] = load ptr, ptr [[REF_ALLOCA]]
  68   // CHECK-NEXT: load i64, ptr [[REF]], align 4
  69 }
  70
  71 _Complex unsigned test_to_complex(unsigned long &ul) {
  72   // CHECK-LABEL: define{{.*}} i64 @_Z15test_to_complexRm
  73
  74   return __builtin_bit_cast(_Complex unsigned, ul);
  75
  76   // CHECK: [[REF:%.*]] = alloca ptr
  77   // CHECK: [[LOAD_REF:%.*]] = load ptr, ptr [[REF]]
  78 }
  79
  80 unsigned long test_array(int (&ary)[2]) {
  81   // CHECK-LABEL: define{{.*}} i64 @_Z10test_arrayRA2_i
  82   return __builtin_bit_cast(unsigned long, ary);
  83
  84   // CHECK: [[REF_ALLOCA:%.*]] = alloca ptr
  85   // CHECK: [[LOAD_REF:%.*]] = load ptr, ptr [[REF_ALLOCA]]
  86   // CHECK: load i64, ptr [[LOAD_REF]], align 4
  87 }
  88
  89 two_ints test_rvalue_aggregate() {
  90   // CHECK-LABEL: define{{.*}} i64 @_Z21test_rvalue_aggregate
  91   return __builtin_bit_cast(two_ints, 42ul);
  92
  93   // CHECK: [[TI:%.*]] = alloca %struct.two_ints, align 4
  94   // CHECK: call void @llvm.memcpy.p0.p0.i64(ptr align 4 [[TI]]
  95 }