libgcc/config/rs6000/quad-float128.h

   1 /* Software floating-point emulation.
   2    Definitions for IEEE Quad Precision on the PowerPC.
   3    Copyright (C) 2016-2022 Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5    Contributed by Michael Meissner (meissner@linux.vnet.ibm.com).
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Lesser General Public
   9    License as published by the Free Software Foundation; either
  10    version 2.1 of the License, or (at your option) any later version.
  11
  12    In addition to the permissions in the GNU Lesser General Public
  13    License, the Free Software Foundation gives you unlimited
  14    permission to link the compiled version of this file into
  15    combinations with other programs, and to distribute those
  16    combinations without any restriction coming from the use of this
  17    file.  (The Lesser General Public License restrictions do apply in
  18    other respects; for example, they cover modification of the file,
  19    and distribution when not linked into a combine executable.)
  20
  21    The GNU C Library is distributed in the hope that it will be useful,
  22    but WITHOUT ANY WARRANTY; without even the implied warranty of
  23    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  24    Lesser General Public License for more details.
  25
  26    You should have received a copy of the GNU Lesser General Public
  27    License along with the GNU C Library; if not, see
  28    <http://www.gnu.org/licenses/>.  */
  29
  30 /* Override the types for IEEE 128-bit scalar and complex.  */
  31 #ifdef __LONG_DOUBLE_IEEE128__
  32 #define TFtype long double
  33 #define TCtype _Complex long double
  34
  35 #else
  36 #define TFtype _Float128
  37 #define TCtype _Complex _Float128
  38 #endif
  39
  40 /* Force the use of the VSX instruction set.  */
  41 #if defined(_ARCH_PPC) && (!defined(__VSX__) || !defined(__FLOAT128__))
  42 #pragma GCC target ("vsx,float128")
  43 #endif
  44
  45 #include <stddef.h>
  46 #include <quad.h>
  47
  48 #define IBM128_TYPE     __ibm128
  49
  50 /* Add prototypes of the library functions created.  In case the appropriate
  51    int/long types are not declared in scope by the time quad.h is included,
  52    provide our own version.  */
  53 typedef int      SItype_ppc  __attribute__ ((__mode__ (__SI__)));
  54 typedef int      DItype_ppc  __attribute__ ((__mode__ (__DI__)));
  55 typedef unsigned USItype_ppc __attribute__ ((__mode__ (__SI__)));
  56 typedef unsigned UDItype_ppc __attribute__ ((__mode__ (__DI__)));
  57
  58 #ifdef _ARCH_PPC64
  59 typedef int      TItype_ppc  __attribute__ ((__mode__ (__TI__)));
  60 typedef unsigned UTItype_ppc __attribute__ ((__mode__ (__TI__)));
  61 #endif
  62
  63 /* Software emulation functions.  */
  64 extern TFtype __addkf3_sw (TFtype, TFtype);
  65 extern TFtype __subkf3_sw (TFtype, TFtype);
  66 extern TFtype __mulkf3_sw (TFtype, TFtype);
  67 extern TFtype __divkf3_sw (TFtype, TFtype);
  68 extern TFtype __negkf2_sw (TFtype);
  69 extern TFtype __powikf2_sw (TFtype, SItype_ppc);
  70 extern CMPtype __eqkf2_sw (TFtype, TFtype);
  71 extern CMPtype __gekf2_sw (TFtype, TFtype);
  72 extern CMPtype __lekf2_sw (TFtype, TFtype);
  73 extern CMPtype __unordkf2_sw (TFtype, TFtype);
  74 extern TFtype __extendsfkf2_sw (float);
  75 extern TFtype __extenddfkf2_sw (double);
  76 extern float __trunckfsf2_sw (TFtype);
  77 extern double __trunckfdf2_sw (TFtype);
  78 extern SItype_ppc __fixkfsi_sw (TFtype);
  79 extern DItype_ppc __fixkfdi_sw (TFtype);
  80 extern USItype_ppc __fixunskfsi_sw (TFtype);
  81 extern UDItype_ppc __fixunskfdi_sw (TFtype);
  82 extern TFtype __floatsikf_sw (SItype_ppc);
  83 extern TFtype __floatdikf_sw (DItype_ppc);
  84 #ifdef _ARCH_PPC64
  85 extern TFtype __floattikf_sw (TItype_ppc);
  86 #endif
  87 extern TFtype __floatunsikf_sw (USItype_ppc);
  88 extern TFtype __floatundikf_sw (UDItype_ppc);
  89 #ifdef _ARCH_PPC64
  90 extern TFtype __floatuntikf_sw (UTItype_ppc);
  91 extern TItype_ppc __fixkfti_sw (TFtype);
  92 extern UTItype_ppc __fixunskfti_sw (TFtype);
  93 #endif
  94 extern IBM128_TYPE __extendkftf2_sw (TFtype);
  95 extern TFtype __trunctfkf2_sw (IBM128_TYPE);
  96 extern TCtype __mulkc3_sw (TFtype, TFtype, TFtype, TFtype);
  97 extern TCtype __divkc3_sw (TFtype, TFtype, TFtype, TFtype);
  98
  99 #ifdef _ARCH_PPC64
 100 extern TItype_ppc __fixkfti (TFtype);
 101 extern UTItype_ppc __fixunskfti (TFtype);
 102 extern TFtype __floattikf (TItype_ppc);
 103 extern TFtype __floatuntikf (UTItype_ppc);
 104 #endif
 105
 106 /* Functions using the ISA 3.0 hardware support.  If the code is compiled with
 107    -mcpu=power9, it will not use these functions, but if it was compiled with
 108    -mcpu=power7 or -mcpu=power8 and run on a ISA 3.0 system, it will use the
 109    hardware instruction.  */
 110 extern TFtype __addkf3_hw (TFtype, TFtype);
 111 extern TFtype __subkf3_hw (TFtype, TFtype);
 112 extern TFtype __mulkf3_hw (TFtype, TFtype);
 113 extern TFtype __divkf3_hw (TFtype, TFtype);
 114 extern TFtype __negkf2_hw (TFtype);
 115 extern TFtype __powikf2_hw (TFtype, SItype_ppc);
 116 extern CMPtype __eqkf2_hw (TFtype, TFtype);
 117 extern CMPtype __gekf2_hw (TFtype, TFtype);
 118 extern CMPtype __lekf2_hw (TFtype, TFtype);
 119 extern CMPtype __unordkf2_hw (TFtype, TFtype);
 120 extern TFtype __extendsfkf2_hw (float);
 121 extern TFtype __extenddfkf2_hw (double);
 122 extern float __trunckfsf2_hw (TFtype);
 123 extern double __trunckfdf2_hw (TFtype);
 124 extern SItype_ppc __fixkfsi_hw (TFtype);
 125 extern DItype_ppc __fixkfdi_hw (TFtype);
 126 extern USItype_ppc __fixunskfsi_hw (TFtype);
 127 extern UDItype_ppc __fixunskfdi_hw (TFtype);
 128 extern TFtype __floatsikf_hw (SItype_ppc);
 129 extern TFtype __floatdikf_hw (DItype_ppc);
 130 #ifdef _ARCH_PPC64
 131 extern TFtype __floattikf_hw (TItype_ppc);
 132 #endif
 133 extern TFtype __floatunsikf_hw (USItype_ppc);
 134 extern TFtype __floatundikf_hw (UDItype_ppc);
 135 #ifdef _ARCH_PPC64
 136 extern TFtype __floatuntikf_hw (UTItype_ppc);
 137 extern TItype_ppc __fixkfti_hw (TFtype);
 138 extern UTItype_ppc __fixunskfti_hw (TFtype);
 139 #endif
 140 extern IBM128_TYPE __extendkftf2_hw (TFtype);
 141 extern TFtype __trunctfkf2_hw (IBM128_TYPE);
 142 extern TCtype __mulkc3_hw (TFtype, TFtype, TFtype, TFtype);
 143 extern TCtype __divkc3_hw (TFtype, TFtype, TFtype, TFtype);
 144
 145 /* Ifunc function declarations, to automatically switch between software
 146    emulation and hardware support.  */
 147 extern TFtype __addkf3 (TFtype, TFtype);
 148 extern TFtype __subkf3 (TFtype, TFtype);
 149 extern TFtype __mulkf3 (TFtype, TFtype);
 150 extern TFtype __divkf3 (TFtype, TFtype);
 151 extern TFtype __negkf2 (TFtype);
 152 extern TFtype __powikf2 (TFtype, SItype_ppc);
 153 extern CMPtype __eqkf2 (TFtype, TFtype);
 154 extern CMPtype __nekf2 (TFtype, TFtype);
 155 extern CMPtype __gekf2 (TFtype, TFtype);
 156 extern CMPtype __gtkf2 (TFtype, TFtype);
 157 extern CMPtype __lekf2 (TFtype, TFtype);
 158 extern CMPtype __ltkf2 (TFtype, TFtype);
 159 extern CMPtype __unordkf2 (TFtype, TFtype);
 160 extern TFtype __extendsfkf2 (float);
 161 extern TFtype __extenddfkf2 (double);
 162 extern float __trunckfsf2 (TFtype);
 163 extern double __trunckfdf2 (TFtype);
 164 extern SItype_ppc __fixkfsi (TFtype);
 165 extern DItype_ppc __fixkfdi (TFtype);
 166 extern USItype_ppc __fixunskfsi (TFtype);
 167 extern UDItype_ppc __fixunskfdi (TFtype);
 168 extern TFtype __floatsikf (SItype_ppc);
 169 extern TFtype __floatdikf (DItype_ppc);
 170 #ifdef _ARCH_PPC64
 171 extern TFtype __floattikf (TItype_ppc);
 172 #endif
 173 extern TFtype __floatunsikf (USItype_ppc);
 174 extern TFtype __floatundikf (UDItype_ppc);
 175 #ifdef _ARCH_PPC64
 176 extern TFtype __floatuntikf (UTItype_ppc);
 177 extern TItype_ppc __fixkfti (TFtype);
 178 extern UTItype_ppc __fixunskfti (TFtype);
 179 #endif
 180 extern IBM128_TYPE __extendkftf2 (TFtype);
 181 extern TFtype __trunctfkf2 (IBM128_TYPE);
 182
 183 /* Complex __float128 built on __float128 interfaces.  */
 184 extern TCtype __mulkc3 (TFtype, TFtype, TFtype, TFtype);
 185 extern TCtype __divkc3 (TFtype, TFtype, TFtype, TFtype);
 186
 187 /* Convert IEEE 128-bit floating point to/from string.  We explicitly use
 188    _Float128 instead of TFmode because _strtokf and _strfromkf must be compiled
 189    with long double being IBM 128.  */
 190 extern _Float128 __strtokf (const char *, char **);
 191 extern int __strfromkf (char *restrict, size_t, const char *restrict,
 192                         _Float128);
 193
 194 /* Implementation of conversions between __ibm128 and __float128, to allow the
 195    same code to be used on systems with IEEE 128-bit emulation and with IEEE
 196    128-bit hardware support.  */
 197
 198 union ibm128_union {
 199   IBM128_TYPE ibm128;
 200   double dbl[2];
 201 };
 202
 203 #define CVT_FLOAT128_TO_IBM128(RESULT, VALUE)                           \
 204 {                                                                       \
 205   double __high, __low;                                                 \
 206   TFtype __value = (VALUE);                                             \
 207   union ibm128_union u;                                                 \
 208                                                                         \
 209   __high = (double) __value;                                            \
 210   if (__builtin_isnan (__high) || __builtin_isinf (__high))             \
 211     __low = 0.0;                                                        \
 212                                                                         \
 213   else                                                                  \
 214     {                                                                   \
 215       double __high_temp;                                               \
 216                                                                         \
 217       __low = (double) (__value - (TFtype) __high);                     \
 218       /* Renormalize low/high and move them into canonical IBM long     \
 219          double form.  */                                               \
 220       __high_temp = __high + __low;                                     \
 221       __low = (__high - __high_temp) + __low;                           \
 222       __high = __high_temp;                                             \
 223     }                                                                   \
 224                                                                         \
 225   u.dbl[0] = __high;                                                    \
 226   u.dbl[1] = __low;                                                     \
 227   RESULT = u.ibm128;                                                    \
 228 }
 229
 230 #define CVT_IBM128_TO_FLOAT128(RESULT, VALUE)                           \
 231 {                                                                       \
 232   union ibm128_union u;                                                 \
 233   double __high, __low;                                                 \
 234                                                                         \
 235   u.ibm128 = (VALUE);                                                   \
 236   __high = u.dbl[0];                                                    \
 237   __low = u.dbl[1];                                                     \
 238                                                                         \
 239   /* Handle the special cases of NAN and infinity.  */                  \
 240   if (__builtin_isnan (__high) || __builtin_isinf (__high))             \
 241     RESULT = (TFtype) __high;                                           \
 242                                                                         \
 243   /* If low is 0.0, there no need to do the add.  In addition,          \
 244      avoiding the add produces the correct sign if high is -0.0.  */    \
 245   else if (__low == 0.0)                                                \
 246     RESULT = (TFtype) __high;                                           \
 247                                                                         \
 248   else                                                                  \
 249     RESULT = ((TFtype) __high) + ((TFtype) __low);                      \
 250 }