clang/test/AST/const-fpfeatures.cpp

   1 // RUN: %clang_cc1 -emit-llvm -triple i386-linux -std=c++2a -Wno-unknown-pragmas %s -o - | FileCheck %s
   2
   3 // nextUp(1.F) == 0x1.000002p0F
   4
   5 constexpr float add_round_down(float x, float y) {
   6   #pragma STDC FENV_ROUND FE_DOWNWARD
   7   float res = x;
   8   res += y;
   9   return res;
  10 }
  11
  12 constexpr float add_round_up(float x, float y) {
  13   #pragma STDC FENV_ROUND FE_UPWARD
  14   float res = x;
  15   res += y;
  16   return res;
  17 }
  18
  19 float V1 = add_round_down(1.0F, 0x0.000001p0F);
  20 float V2 = add_round_up(1.0F, 0x0.000001p0F);
  21 // CHECK: @V1 = {{.*}} float 1.000000e+00
  22 // CHECK: @V2 = {{.*}} float 0x3FF0000020000000
  23
  24 constexpr float add_cast_round_down(float x, double y) {
  25   #pragma STDC FENV_ROUND FE_DOWNWARD
  26   float res = x;
  27   res += y;
  28   return res;
  29 }
  30
  31 constexpr float add_cast_round_up(float x, double y) {
  32   #pragma STDC FENV_ROUND FE_UPWARD
  33   float res = x;
  34   res += y;
  35   return res;
  36 }
  37
  38 float V3 = add_cast_round_down(1.0F, 0x0.000001p0F);
  39 float V4 = add_cast_round_up(1.0F, 0x0.000001p0F);
  40
  41 // CHECK: @V3 = {{.*}} float 1.000000e+00
  42 // CHECK: @V4 = {{.*}} float 0x3FF0000020000000
  43
  44 // The next three variables use the same function as initializer, only rounding
  45 // modes differ.
  46
  47 float V5 = []() -> float {
  48   return [](float x, float y)->float {
  49     #pragma STDC FENV_ROUND FE_UPWARD
  50     return x + y;
  51   }([](float x, float y) -> float {
  52       #pragma STDC FENV_ROUND FE_UPWARD
  53       return x + y;
  54     }(1.0F, 0x0.000001p0F),
  55   0x0.000001p0F);
  56 }();
  57 // CHECK: @V5 = {{.*}} float 0x3FF0000040000000
  58
  59 float V6 = []() -> float {
  60   return [](float x, float y)->float {
  61     #pragma STDC FENV_ROUND FE_DOWNWARD
  62     return x + y;
  63   }([](float x, float y) -> float {
  64       #pragma STDC FENV_ROUND FE_UPWARD
  65       return x + y;
  66     }(1.0F, 0x0.000001p0F),
  67   0x0.000001p0F);
  68 }();
  69 // CHECK: @V6 = {{.*}} float 0x3FF0000020000000
  70
  71 float V7 = []() -> float {
  72   return [](float x, float y)->float {
  73     #pragma STDC FENV_ROUND FE_DOWNWARD
  74     return x + y;
  75   }([](float x, float y) -> float {
  76       #pragma STDC FENV_ROUND FE_DOWNWARD
  77       return x + y;
  78     }(1.0F, 0x0.000001p0F),
  79   0x0.000001p0F);
  80 }();
  81 // CHECK: @V7 = {{.*}} float 1.000000e+00
  82
  83 #pragma STDC FENV_ROUND FE_DYNAMIC
  84
  85 template<float V> struct L {
  86   constexpr L() : value(V) {}
  87   float value;
  88 };
  89
  90 #pragma STDC FENV_ROUND FE_DOWNWARD
  91 L<0.1F> val_d;
  92 // CHECK: @val_d = {{.*}} { float 0x3FB9999980000000 }
  93
  94 #pragma STDC FENV_ROUND FE_UPWARD
  95 L<0.1F> val_u;
  96 // CHECK: @val_u = {{.*}} { float 0x3FB99999A0000000 }
  97
  98
  99 // Check literals in macros.
 100
 101 #pragma STDC FENV_ROUND FE_DOWNWARD
 102 #define CONSTANT_0_1 0.1F
 103
 104 #pragma STDC FENV_ROUND FE_UPWARD
 105 float C1_ru = CONSTANT_0_1;
 106 // CHECK: @C1_ru = {{.*}} float 0x3FB99999A0000000
 107
 108 #pragma STDC FENV_ROUND FE_DOWNWARD
 109 float C1_rd = CONSTANT_0_1;
 110 // CHECK: @C1_rd = {{.*}} float 0x3FB9999980000000
 111
 112 #pragma STDC FENV_ROUND FE_DOWNWARD
 113 #define PRAGMA(x) _Pragma(#x)
 114 #define CONSTANT_0_1_RM(v, rm) ([](){ PRAGMA(STDC FENV_ROUND rm); return v; }())
 115
 116 #pragma STDC FENV_ROUND FE_UPWARD
 117 float C2_rd = CONSTANT_0_1_RM(0.1F, FE_DOWNWARD);
 118 float C2_ru = CONSTANT_0_1_RM(0.1F, FE_UPWARD);
 119 // CHECK: @C2_rd = {{.*}} float 0x3FB9999980000000
 120 // CHECK: @C2_ru = {{.*}} float 0x3FB99999A0000000
 121
 122 #pragma STDC FENV_ROUND FE_DOWNWARD
 123 float C3_rd = CONSTANT_0_1_RM(0.1F, FE_DOWNWARD);
 124 float C3_ru = CONSTANT_0_1_RM(0.1F, FE_UPWARD);
 125 // CHECK: @C3_rd = {{.*}} float 0x3FB9999980000000
 126 // CHECK: @C3_ru = {{.*}} float 0x3FB99999A0000000
 127
 128 // Check literals in template instantiations.
 129
 130 #pragma STDC FENV_ROUND FE_DYNAMIC
 131
 132 template<typename T, T C>
 133 constexpr T foo() {
 134   return C;
 135 }
 136
 137 #pragma STDC FENV_ROUND FE_DOWNWARD
 138 float var_d = foo<float, 0.1F>();
 139 // CHECK: @var_d = {{.*}} float 0x3FB9999980000000
 140
 141 #pragma STDC FENV_ROUND FE_UPWARD
 142 float var_u = foo<float, 0.1F>();
 143 // CHECK: @var_u = {{.*}} float 0x3FB99999A0000000
 144
 145 #pragma STDC FENV_ROUND FE_DYNAMIC
 146
 147 template<typename T, T f> void foo2() {
 148   T Val = f;
 149 }
 150
 151 void func_01() {
 152   #pragma STDC FENV_ROUND FE_DOWNWARD
 153   foo2<float, 0.1f>();
 154 }
 155
 156 void func_02() {
 157   #pragma STDC FENV_ROUND FE_UPWARD
 158   foo2<float, 0.1f>();
 159 }
 160
 161 // CHECK-LABEL: define {{.*}} void @_Z4foo2IfTnT_Lf3dccccccEEvv()
 162 // CHECK:         store float 0x3FB9999980000000, ptr
 163
 164 // CHECK-LABEL: define {{.*}} void @_Z4foo2IfTnT_Lf3dcccccdEEvv()
 165 // CHECK:         store float 0x3FB99999A0000000, ptr
 166
 167
 168 #pragma STDC FENV_ROUND FE_DOWNWARD
 169 template <int C>
 170 float tfunc_01() {
 171   return 0.1F;  // Must be 0x3FB9999980000000 in all instantiations.
 172 }
 173 template float tfunc_01<0>();
 174 // CHECK-LABEL: define {{.*}} float @_Z8tfunc_01ILi0EEfv()
 175 // CHECK:         ret float 0x3FB9999980000000
 176
 177 #pragma STDC FENV_ROUND FE_UPWARD
 178 template float tfunc_01<1>();
 179 // CHECK-LABEL: define {{.*}} float @_Z8tfunc_01ILi1EEfv()
 180 // CHECK:         ret float 0x3FB9999980000000
 181
 182 template<> float tfunc_01<2>() {
 183   return 0.1F;
 184 }
 185 // CHECK-LABEL: define {{.*}} float @_Z8tfunc_01ILi2EEfv()
 186 // CHECK:         ret float 0x3FB99999A0000000