VEX/priv/guest_generic_x87.h

   1
   2 /*---------------------------------------------------------------*/
   3 /*--- begin                               guest_generic_x87.h ---*/
   4 /*---------------------------------------------------------------*/
   5
   6 /*
   7    This file is part of Valgrind, a dynamic binary instrumentation
   8    framework.
   9
  10    Copyright (C) 2004-2017 OpenWorks LLP
  11       info@open-works.net
  12
  13    This program is free software; you can redistribute it and/or
  14    modify it under the terms of the GNU General Public License as
  15    published by the Free Software Foundation; either version 2 of the
  16    License, or (at your option) any later version.
  17
  18    This program is distributed in the hope that it will be useful, but
  19    WITHOUT ANY WARRANTY; without even the implied warranty of
  20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21    General Public License for more details.
  22
  23    You should have received a copy of the GNU General Public License
  24    along with this program; if not, see <http://www.gnu.org/licenses/>.
  25
  26    The GNU General Public License is contained in the file COPYING.
  27
  28    Neither the names of the U.S. Department of Energy nor the
  29    University of California nor the names of its contributors may be
  30    used to endorse or promote products derived from this software
  31    without prior written permission.
  32 */
  33
  34 /* This file contains functions for doing some x87-specific
  35    operations.  Both the amd64 and x86 front ends (guests) indirectly
  36    call these functions via guest helper calls.  By putting them here,
  37    code duplication is avoided.  Some of these functions are tricky
  38    and hard to verify, so there is much to be said for only having one
  39    copy thereof.
  40 */
  41
  42 #ifndef __VEX_GUEST_GENERIC_X87_H
  43 #define __VEX_GUEST_GENERIC_X87_H
  44
  45 #include "libvex_basictypes.h"
  46
  47
  48 /* Convert an IEEE754 double (64-bit) into an x87 extended double
  49    (80-bit), mimicing the hardware fairly closely.  Both numbers are
  50    stored little-endian.  Limitations, all of which could be fixed,
  51    given some level of hassle:
  52
  53    * Identity of NaNs is not preserved.
  54
  55    See comments in the code for more details.
  56 */
  57 extern
  58 void convert_f64le_to_f80le ( /*IN*/UChar* f64, /*OUT*/UChar* f80 );
  59
  60
  61 /* Convert an x87 extended double (80-bit) into an IEEE 754 double
  62    (64-bit), mimicking the hardware fairly closely.  Both numbers are
  63    stored little-endian.  Limitations, both of which could be fixed,
  64    given some level of hassle:
  65
  66    * Rounding following truncation could be a bit better.
  67
  68    * Identity of NaNs is not preserved.
  69
  70    See comments in the code for more details.
  71 */
  72 extern
  73 void convert_f80le_to_f64le ( /*IN*/UChar* f80, /*OUT*/UChar* f64 );
  74
  75
  76 /* Layout of the real x87 state. */
  77 typedef
  78    struct {
  79       UShort env[14];
  80       UChar  reg[80];
  81    }
  82    Fpu_State;
  83
  84 /* Offsets, in 16-bit ints, into the FPU environment (env) area. */
  85 #define FP_ENV_CTRL   0
  86 #define FP_ENV_STAT   2
  87 #define FP_ENV_TAG    4
  88 #define FP_ENV_IP     6 /* and 7 */
  89 #define FP_ENV_CS     8
  90 #define FP_ENV_LSTOP  9
  91 #define FP_ENV_OPOFF  10 /* and 11 */
  92 #define FP_ENV_OPSEL  12
  93 #define FP_REG(ii)    (10*(7-(ii)))
  94
  95
  96 /* Layout of the 16-bit FNSAVE x87 state. */
  97 typedef
  98    struct {
  99       UShort env[7];
 100       UChar  reg[80];
 101    }
 102    Fpu_State_16;
 103
 104 /* Offsets, in 16-bit ints, into the FPU environment (env) area. */
 105 #define FPS_ENV_CTRL   0
 106 #define FPS_ENV_STAT   1
 107 #define FPS_ENV_TAG    2
 108 #define FPS_ENV_IP     3
 109 #define FPS_ENV_CS     4
 110 #define FPS_ENV_OPOFF  5
 111 #define FPS_ENV_OPSEL  6
 112
 113
 114 /* Do the computations for x86/amd64 FXTRACT.  Called directly from
 115    generated code.  CLEAN HELPER. */
 116 extern ULong x86amd64g_calculate_FXTRACT ( ULong arg, HWord getExp );
 117
 118 /* Compute result and new OSZACP flags for all 8-bit PCMP{E,I}STR{I,M}
 119    variants.  See bigger comment on implementation of this function
 120    for details on call/return conventions. */
 121 extern Bool compute_PCMPxSTRx ( /*OUT*/V128* resV,
 122                                 /*OUT*/UInt* resOSZACP,
 123                                 V128* argLV,  V128* argRV,
 124                                 UInt zmaskL, UInt zmaskR,
 125                                 UInt imm8,   Bool isxSTRM );
 126
 127 /* Compute result and new OSZACP flags for all 16-bit PCMP{E,I}STR{I,M}
 128    variants.  See bigger comment on implementation of this function
 129    for details on call/return conventions. */
 130 extern Bool compute_PCMPxSTRx_wide ( /*OUT*/V128* resV,
 131                                      /*OUT*/UInt* resOSZACP,
 132                                      V128* argLV,  V128* argRV,
 133                                      UInt zmaskL, UInt zmaskR,
 134                                      UInt imm8,   Bool isxSTRM );
 135
 136 #endif /* ndef __VEX_GUEST_GENERIC_X87_H */
 137
 138 /*---------------------------------------------------------------*/
 139 /*--- end                                 guest_generic_x87.h ---*/
 140 /*---------------------------------------------------------------*/