| /* Intel 387 floating point stuff. |
| Copyright 1988, 1989, 1991, 1992, 1993, 1994, 1998, 1999, 2000, |
| 2001, 2002 Free Software Foundation, Inc. |
| |
| This file is part of GDB. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program; if not, write to the Free Software |
| Foundation, Inc., 59 Temple Place - Suite 330, |
| Boston, MA 02111-1307, USA. */ |
| |
| #include "defs.h" |
| #include "frame.h" |
| #include "inferior.h" |
| #include "language.h" |
| #include "value.h" |
| #include "gdbcore.h" |
| #include "floatformat.h" |
| #include "regcache.h" |
| #include "gdb_assert.h" |
| #include "gdb_string.h" |
| #include "doublest.h" |
| |
| #include "i386-tdep.h" |
| |
| /* FIXME: Eliminate the next two functions when we have the time to |
| change all the callers. */ |
| |
| void i387_to_double (char *from, char *to); |
| void double_to_i387 (char *from, char *to); |
| |
| void |
| i387_to_double (char *from, char *to) |
| { |
| floatformat_to_double (&floatformat_i387_ext, from, (double *) to); |
| } |
| |
| void |
| double_to_i387 (char *from, char *to) |
| { |
| floatformat_from_double (&floatformat_i387_ext, (double *) from, to); |
| } |
| |
| |
| /* FIXME: The functions on this page are used by the old `info float' |
| implementations that a few of the i386 targets provide. These |
| functions should be removed if all of these have been converted to |
| use the generic implementation based on the new register file |
| layout. */ |
| |
| static void print_387_control_bits (unsigned int control); |
| static void print_387_status_bits (unsigned int status); |
| |
| static void |
| print_387_control_bits (unsigned int control) |
| { |
| switch ((control >> 8) & 3) |
| { |
| case 0: |
| puts_unfiltered (" 24 bit; "); |
| break; |
| case 1: |
| puts_unfiltered (" (bad); "); |
| break; |
| case 2: |
| puts_unfiltered (" 53 bit; "); |
| break; |
| case 3: |
| puts_unfiltered (" 64 bit; "); |
| break; |
| } |
| switch ((control >> 10) & 3) |
| { |
| case 0: |
| puts_unfiltered ("NEAR; "); |
| break; |
| case 1: |
| puts_unfiltered ("DOWN; "); |
| break; |
| case 2: |
| puts_unfiltered ("UP; "); |
| break; |
| case 3: |
| puts_unfiltered ("CHOP; "); |
| break; |
| } |
| if (control & 0x3f) |
| { |
| puts_unfiltered ("mask"); |
| if (control & 0x0001) |
| puts_unfiltered (" INVAL"); |
| if (control & 0x0002) |
| puts_unfiltered (" DENOR"); |
| if (control & 0x0004) |
| puts_unfiltered (" DIVZ"); |
| if (control & 0x0008) |
| puts_unfiltered (" OVERF"); |
| if (control & 0x0010) |
| puts_unfiltered (" UNDER"); |
| if (control & 0x0020) |
| puts_unfiltered (" LOS"); |
| puts_unfiltered (";"); |
| } |
| |
| if (control & 0xe080) |
| warning ("\nreserved bits on: %s", |
| local_hex_string (control & 0xe080)); |
| } |
| |
| void |
| print_387_control_word (unsigned int control) |
| { |
| printf_filtered ("control %s:", local_hex_string(control & 0xffff)); |
| print_387_control_bits (control); |
| puts_unfiltered ("\n"); |
| } |
| |
| static void |
| print_387_status_bits (unsigned int status) |
| { |
| printf_unfiltered (" flags %d%d%d%d; ", |
| (status & 0x4000) != 0, |
| (status & 0x0400) != 0, |
| (status & 0x0200) != 0, |
| (status & 0x0100) != 0); |
| printf_unfiltered ("top %d; ", (status >> 11) & 7); |
| if (status & 0xff) |
| { |
| puts_unfiltered ("excep"); |
| if (status & 0x0001) puts_unfiltered (" INVAL"); |
| if (status & 0x0002) puts_unfiltered (" DENOR"); |
| if (status & 0x0004) puts_unfiltered (" DIVZ"); |
| if (status & 0x0008) puts_unfiltered (" OVERF"); |
| if (status & 0x0010) puts_unfiltered (" UNDER"); |
| if (status & 0x0020) puts_unfiltered (" LOS"); |
| if (status & 0x0040) puts_unfiltered (" STACK"); |
| } |
| } |
| |
| void |
| print_387_status_word (unsigned int status) |
| { |
| printf_filtered ("status %s:", local_hex_string (status & 0xffff)); |
| print_387_status_bits (status); |
| puts_unfiltered ("\n"); |
| } |
| |
| |
| /* Implement the `info float' layout based on the register definitions |
| in `tm-i386.h'. */ |
| |
| /* Print the floating point number specified by RAW. */ |
| static void |
| print_i387_value (char *raw, struct ui_file *file) |
| { |
| DOUBLEST value; |
| |
| /* Using extract_typed_floating here might affect the representation |
| of certain numbers such as NaNs, even if GDB is running natively. |
| This is fine since our caller already detects such special |
| numbers and we print the hexadecimal representation anyway. */ |
| value = extract_typed_floating (raw, builtin_type_i387_ext); |
| |
| /* We try to print 19 digits. The last digit may or may not contain |
| garbage, but we'd better print one too many. We need enough room |
| to print the value, 1 position for the sign, 1 for the decimal |
| point, 19 for the digits and 6 for the exponent adds up to 27. */ |
| #ifdef PRINTF_HAS_LONG_DOUBLE |
| fprintf_filtered (file, " %-+27.19Lg", (long double) value); |
| #else |
| fprintf_filtered (file, " %-+27.19g", (double) value); |
| #endif |
| } |
| |
| /* Print the classification for the register contents RAW. */ |
| static void |
| print_i387_ext (unsigned char *raw, struct ui_file *file) |
| { |
| int sign; |
| int integer; |
| unsigned int exponent; |
| unsigned long fraction[2]; |
| |
| sign = raw[9] & 0x80; |
| integer = raw[7] & 0x80; |
| exponent = (((raw[9] & 0x7f) << 8) | raw[8]); |
| fraction[0] = ((raw[3] << 24) | (raw[2] << 16) | (raw[1] << 8) | raw[0]); |
| fraction[1] = (((raw[7] & 0x7f) << 24) | (raw[6] << 16) |
| | (raw[5] << 8) | raw[4]); |
| |
| if (exponent == 0x7fff && integer) |
| { |
| if (fraction[0] == 0x00000000 && fraction[1] == 0x00000000) |
| /* Infinity. */ |
| fprintf_filtered (file, " %cInf", (sign ? '-' : '+')); |
| else if (sign && fraction[0] == 0x00000000 && fraction[1] == 0x40000000) |
| /* Real Indefinite (QNaN). */ |
| fputs_unfiltered (" Real Indefinite (QNaN)", file); |
| else if (fraction[1] & 0x40000000) |
| /* QNaN. */ |
| fputs_filtered (" QNaN", file); |
| else |
| /* SNaN. */ |
| fputs_filtered (" SNaN", file); |
| } |
| else if (exponent < 0x7fff && exponent > 0x0000 && integer) |
| /* Normal. */ |
| print_i387_value (raw, file); |
| else if (exponent == 0x0000) |
| { |
| /* Denormal or zero. */ |
| print_i387_value (raw, file); |
| |
| if (integer) |
| /* Pseudo-denormal. */ |
| fputs_filtered (" Pseudo-denormal", file); |
| else if (fraction[0] || fraction[1]) |
| /* Denormal. */ |
| fputs_filtered (" Denormal", file); |
| } |
| else |
| /* Unsupported. */ |
| fputs_filtered (" Unsupported", file); |
| } |
| |
| /* Print the status word STATUS. */ |
| static void |
| print_i387_status_word (unsigned int status, struct ui_file *file) |
| { |
| fprintf_filtered (file, "Status Word: %s", |
| local_hex_string_custom (status, "04")); |
| fputs_filtered (" ", file); |
| fprintf_filtered (file, " %s", (status & 0x0001) ? "IE" : " "); |
| fprintf_filtered (file, " %s", (status & 0x0002) ? "DE" : " "); |
| fprintf_filtered (file, " %s", (status & 0x0004) ? "ZE" : " "); |
| fprintf_filtered (file, " %s", (status & 0x0008) ? "OE" : " "); |
| fprintf_filtered (file, " %s", (status & 0x0010) ? "UE" : " "); |
| fprintf_filtered (file, " %s", (status & 0x0020) ? "PE" : " "); |
| fputs_filtered (" ", file); |
| fprintf_filtered (file, " %s", (status & 0x0080) ? "ES" : " "); |
| fputs_filtered (" ", file); |
| fprintf_filtered (file, " %s", (status & 0x0040) ? "SF" : " "); |
| fputs_filtered (" ", file); |
| fprintf_filtered (file, " %s", (status & 0x0100) ? "C0" : " "); |
| fprintf_filtered (file, " %s", (status & 0x0200) ? "C1" : " "); |
| fprintf_filtered (file, " %s", (status & 0x0400) ? "C2" : " "); |
| fprintf_filtered (file, " %s", (status & 0x4000) ? "C3" : " "); |
| |
| fputs_filtered ("\n", file); |
| |
| fprintf_filtered (file, |
| " TOP: %d\n", ((status >> 11) & 7)); |
| } |
| |
| /* Print the control word CONTROL. */ |
| static void |
| print_i387_control_word (unsigned int control, struct ui_file *file) |
| { |
| fprintf_filtered (file, "Control Word: %s", |
| local_hex_string_custom (control, "04")); |
| fputs_filtered (" ", file); |
| fprintf_filtered (file, " %s", (control & 0x0001) ? "IM" : " "); |
| fprintf_filtered (file, " %s", (control & 0x0002) ? "DM" : " "); |
| fprintf_filtered (file, " %s", (control & 0x0004) ? "ZM" : " "); |
| fprintf_filtered (file, " %s", (control & 0x0008) ? "OM" : " "); |
| fprintf_filtered (file, " %s", (control & 0x0010) ? "UM" : " "); |
| fprintf_filtered (file, " %s", (control & 0x0020) ? "PM" : " "); |
| |
| fputs_filtered ("\n", file); |
| |
| fputs_filtered (" PC: ", file); |
| switch ((control >> 8) & 3) |
| { |
| case 0: |
| fputs_filtered ("Single Precision (24-bits)\n", file); |
| break; |
| case 1: |
| fputs_filtered ("Reserved\n", file); |
| break; |
| case 2: |
| fputs_filtered ("Double Precision (53-bits)\n", file); |
| break; |
| case 3: |
| fputs_filtered ("Extended Precision (64-bits)\n", file); |
| break; |
| } |
| |
| fputs_filtered (" RC: ", file); |
| switch ((control >> 10) & 3) |
| { |
| case 0: |
| fputs_filtered ("Round to nearest\n", file); |
| break; |
| case 1: |
| fputs_filtered ("Round down\n", file); |
| break; |
| case 2: |
| fputs_filtered ("Round up\n", file); |
| break; |
| case 3: |
| fputs_filtered ("Round toward zero\n", file); |
| break; |
| } |
| } |
| |
| /* Print out the i387 floating point state. Note that we ignore FRAME |
| in the code below. That's OK since floating-point registers are |
| never saved on the stack. */ |
| |
| void |
| i387_print_float_info (struct gdbarch *gdbarch, struct ui_file *file, |
| struct frame_info *frame, const char *args) |
| { |
| char buf[4]; |
| ULONGEST fctrl; |
| ULONGEST fstat; |
| ULONGEST ftag; |
| ULONGEST fiseg; |
| ULONGEST fioff; |
| ULONGEST foseg; |
| ULONGEST fooff; |
| ULONGEST fop; |
| int fpreg; |
| int top; |
| |
| frame_register_read (frame, FCTRL_REGNUM, buf); |
| fctrl = extract_unsigned_integer (buf, 4); |
| frame_register_read (frame, FSTAT_REGNUM, buf); |
| fstat = extract_unsigned_integer (buf, 4); |
| frame_register_read (frame, FTAG_REGNUM, buf); |
| ftag = extract_unsigned_integer (buf, 4); |
| frame_register_read (frame, FISEG_REGNUM, buf); |
| fiseg = extract_unsigned_integer (buf, 4); |
| frame_register_read (frame, FIOFF_REGNUM, buf); |
| fioff = extract_unsigned_integer (buf, 4); |
| frame_register_read (frame, FOSEG_REGNUM, buf); |
| foseg = extract_unsigned_integer (buf, 4); |
| frame_register_read (frame, FOOFF_REGNUM, buf); |
| fooff = extract_unsigned_integer (buf, 4); |
| frame_register_read (frame, FOP_REGNUM, buf); |
| fop = extract_unsigned_integer (buf, 4); |
| |
| top = ((fstat >> 11) & 7); |
| |
| for (fpreg = 7; fpreg >= 0; fpreg--) |
| { |
| unsigned char raw[FPU_REG_RAW_SIZE]; |
| int tag = (ftag >> (fpreg * 2)) & 3; |
| int i; |
| |
| fprintf_filtered (file, "%sR%d: ", fpreg == top ? "=>" : " ", fpreg); |
| |
| switch (tag) |
| { |
| case 0: |
| fputs_filtered ("Valid ", file); |
| break; |
| case 1: |
| fputs_filtered ("Zero ", file); |
| break; |
| case 2: |
| fputs_filtered ("Special ", file); |
| break; |
| case 3: |
| fputs_filtered ("Empty ", file); |
| break; |
| } |
| |
| frame_register_read (frame, (fpreg + 8 - top) % 8 + FP0_REGNUM, raw); |
| |
| fputs_filtered ("0x", file); |
| for (i = 9; i >= 0; i--) |
| fprintf_filtered (file, "%02x", raw[i]); |
| |
| if (tag != 3) |
| print_i387_ext (raw, file); |
| |
| fputs_filtered ("\n", file); |
| } |
| |
| fputs_filtered ("\n", file); |
| |
| print_i387_status_word (fstat, file); |
| print_i387_control_word (fctrl, file); |
| fprintf_filtered (file, "Tag Word: %s\n", |
| local_hex_string_custom (ftag, "04")); |
| fprintf_filtered (file, "Instruction Pointer: %s:", |
| local_hex_string_custom (fiseg, "02")); |
| fprintf_filtered (file, "%s\n", local_hex_string_custom (fioff, "08")); |
| fprintf_filtered (file, "Operand Pointer: %s:", |
| local_hex_string_custom (foseg, "02")); |
| fprintf_filtered (file, "%s\n", local_hex_string_custom (fooff, "08")); |
| fprintf_filtered (file, "Opcode: %s\n", |
| local_hex_string_custom (fop ? (fop | 0xd800) : 0, "04")); |
| } |
| |
| /* FIXME: kettenis/2000-05-21: Right now more than a few i386 targets |
| define their own routines to manage the floating-point registers in |
| GDB's register array. Most (if not all) of these targets use the |
| format used by the "fsave" instruction in their communication with |
| the OS. They should all be converted to use the routines below. */ |
| |
| /* At fsave_offset[REGNUM] you'll find the offset to the location in |
| the data structure used by the "fsave" instruction where GDB |
| register REGNUM is stored. */ |
| |
| static int fsave_offset[] = |
| { |
| 28 + 0 * FPU_REG_RAW_SIZE, /* FP0_REGNUM through ... */ |
| 28 + 1 * FPU_REG_RAW_SIZE, |
| 28 + 2 * FPU_REG_RAW_SIZE, |
| 28 + 3 * FPU_REG_RAW_SIZE, |
| 28 + 4 * FPU_REG_RAW_SIZE, |
| 28 + 5 * FPU_REG_RAW_SIZE, |
| 28 + 6 * FPU_REG_RAW_SIZE, |
| 28 + 7 * FPU_REG_RAW_SIZE, /* ... FP7_REGNUM. */ |
| 0, /* FCTRL_REGNUM (16 bits). */ |
| 4, /* FSTAT_REGNUM (16 bits). */ |
| 8, /* FTAG_REGNUM (16 bits). */ |
| 16, /* FISEG_REGNUM (16 bits). */ |
| 12, /* FIOFF_REGNUM. */ |
| 24, /* FOSEG_REGNUM. */ |
| 20, /* FOOFF_REGNUM. */ |
| 18 /* FOP_REGNUM (bottom 11 bits). */ |
| }; |
| |
| #define FSAVE_ADDR(fsave, regnum) (fsave + fsave_offset[regnum - FP0_REGNUM]) |
| |
| |
| /* Fill register REGNUM in GDB's register array with the appropriate |
| value from *FSAVE. This function masks off any of the reserved |
| bits in *FSAVE. */ |
| |
| void |
| i387_supply_register (int regnum, char *fsave) |
| { |
| /* Most of the FPU control registers occupy only 16 bits in |
| the fsave area. Give those a special treatment. */ |
| if (regnum >= FPC_REGNUM |
| && regnum != FIOFF_REGNUM && regnum != FOOFF_REGNUM) |
| { |
| unsigned char val[4]; |
| |
| memcpy (val, FSAVE_ADDR (fsave, regnum), 2); |
| val[2] = val[3] = 0; |
| if (regnum == FOP_REGNUM) |
| val[1] &= ((1 << 3) - 1); |
| supply_register (regnum, val); |
| } |
| else |
| supply_register (regnum, FSAVE_ADDR (fsave, regnum)); |
| } |
| |
| /* Fill GDB's register array with the floating-point register values |
| in *FSAVE. This function masks off any of the reserved |
| bits in *FSAVE. */ |
| |
| void |
| i387_supply_fsave (char *fsave) |
| { |
| int i; |
| |
| for (i = FP0_REGNUM; i < XMM0_REGNUM; i++) |
| i387_supply_register (i, fsave); |
| } |
| |
| /* Fill register REGNUM (if it is a floating-point register) in *FSAVE |
| with the value in GDB's register array. If REGNUM is -1, do this |
| for all registers. This function doesn't touch any of the reserved |
| bits in *FSAVE. */ |
| |
| void |
| i387_fill_fsave (char *fsave, int regnum) |
| { |
| int i; |
| |
| for (i = FP0_REGNUM; i < XMM0_REGNUM; i++) |
| if (regnum == -1 || regnum == i) |
| { |
| /* Most of the FPU control registers occupy only 16 bits in |
| the fsave area. Give those a special treatment. */ |
| if (i >= FPC_REGNUM |
| && i != FIOFF_REGNUM && i != FOOFF_REGNUM) |
| { |
| unsigned char buf[4]; |
| |
| regcache_collect (i, buf); |
| |
| if (i == FOP_REGNUM) |
| { |
| /* The opcode occupies only 11 bits. Make sure we |
| don't touch the other bits. */ |
| buf[1] &= ((1 << 3) - 1); |
| buf[1] |= ((FSAVE_ADDR (fsave, i))[1] & ~((1 << 3) - 1)); |
| } |
| memcpy (FSAVE_ADDR (fsave, i), buf, 2); |
| } |
| else |
| regcache_collect (i, FSAVE_ADDR (fsave, i)); |
| } |
| } |
| |
| |
| /* At fxsave_offset[REGNUM] you'll find the offset to the location in |
| the data structure used by the "fxsave" instruction where GDB |
| register REGNUM is stored. */ |
| |
| static int fxsave_offset[] = |
| { |
| 32, /* FP0_REGNUM through ... */ |
| 48, |
| 64, |
| 80, |
| 96, |
| 112, |
| 128, |
| 144, /* ... FP7_REGNUM (80 bits each). */ |
| 0, /* FCTRL_REGNUM (16 bits). */ |
| 2, /* FSTAT_REGNUM (16 bits). */ |
| 4, /* FTAG_REGNUM (16 bits). */ |
| 12, /* FISEG_REGNUM (16 bits). */ |
| 8, /* FIOFF_REGNUM. */ |
| 20, /* FOSEG_REGNUM (16 bits). */ |
| 16, /* FOOFF_REGNUM. */ |
| 6, /* FOP_REGNUM (bottom 11 bits). */ |
| 160, /* XMM0_REGNUM through ... */ |
| 176, |
| 192, |
| 208, |
| 224, |
| 240, |
| 256, |
| 272, /* ... XMM7_REGNUM (128 bits each). */ |
| 24, /* MXCSR_REGNUM. */ |
| }; |
| |
| #define FXSAVE_ADDR(fxsave, regnum) \ |
| (fxsave + fxsave_offset[regnum - FP0_REGNUM]) |
| |
| static int i387_tag (unsigned char *raw); |
| |
| |
| /* Fill GDB's register array with the floating-point and SSE register |
| values in *FXSAVE. This function masks off any of the reserved |
| bits in *FXSAVE. */ |
| |
| void |
| i387_supply_fxsave (char *fxsave) |
| { |
| int i, last_regnum = MXCSR_REGNUM; |
| |
| if (gdbarch_tdep (current_gdbarch)->num_xmm_regs == 0) |
| last_regnum = FOP_REGNUM; |
| |
| for (i = FP0_REGNUM; i <= last_regnum; i++) |
| { |
| /* Most of the FPU control registers occupy only 16 bits in |
| the fxsave area. Give those a special treatment. */ |
| if (i >= FPC_REGNUM && i < XMM0_REGNUM |
| && i != FIOFF_REGNUM && i != FOOFF_REGNUM) |
| { |
| unsigned char val[4]; |
| |
| memcpy (val, FXSAVE_ADDR (fxsave, i), 2); |
| val[2] = val[3] = 0; |
| if (i == FOP_REGNUM) |
| val[1] &= ((1 << 3) - 1); |
| else if (i== FTAG_REGNUM) |
| { |
| /* The fxsave area contains a simplified version of the |
| tag word. We have to look at the actual 80-bit FP |
| data to recreate the traditional i387 tag word. */ |
| |
| unsigned long ftag = 0; |
| int fpreg; |
| int top; |
| |
| top = (((FXSAVE_ADDR (fxsave, FSTAT_REGNUM))[1] >> 3) & 0x7); |
| |
| for (fpreg = 7; fpreg >= 0; fpreg--) |
| { |
| int tag; |
| |
| if (val[0] & (1 << fpreg)) |
| { |
| int regnum = (fpreg + 8 - top) % 8 + FP0_REGNUM; |
| tag = i387_tag (FXSAVE_ADDR (fxsave, regnum)); |
| } |
| else |
| tag = 3; /* Empty */ |
| |
| ftag |= tag << (2 * fpreg); |
| } |
| val[0] = ftag & 0xff; |
| val[1] = (ftag >> 8) & 0xff; |
| } |
| supply_register (i, val); |
| } |
| else |
| supply_register (i, FXSAVE_ADDR (fxsave, i)); |
| } |
| } |
| |
| /* Fill register REGNUM (if it is a floating-point or SSE register) in |
| *FXSAVE with the value in GDB's register array. If REGNUM is -1, do |
| this for all registers. This function doesn't touch any of the |
| reserved bits in *FXSAVE. */ |
| |
| void |
| i387_fill_fxsave (char *fxsave, int regnum) |
| { |
| int i, last_regnum = MXCSR_REGNUM; |
| |
| if (gdbarch_tdep (current_gdbarch)->num_xmm_regs == 0) |
| last_regnum = FOP_REGNUM; |
| |
| for (i = FP0_REGNUM; i <= last_regnum; i++) |
| if (regnum == -1 || regnum == i) |
| { |
| /* Most of the FPU control registers occupy only 16 bits in |
| the fxsave area. Give those a special treatment. */ |
| if (i >= FPC_REGNUM && i < XMM0_REGNUM |
| && i != FIOFF_REGNUM && i != FDOFF_REGNUM) |
| { |
| unsigned char buf[4]; |
| |
| regcache_collect (i, buf); |
| |
| if (i == FOP_REGNUM) |
| { |
| /* The opcode occupies only 11 bits. Make sure we |
| don't touch the other bits. */ |
| buf[1] &= ((1 << 3) - 1); |
| buf[1] |= ((FXSAVE_ADDR (fxsave, i))[1] & ~((1 << 3) - 1)); |
| } |
| else if (i == FTAG_REGNUM) |
| { |
| /* Converting back is much easier. */ |
| |
| unsigned short ftag; |
| int fpreg; |
| |
| ftag = (buf[1] << 8) | buf[0]; |
| buf[0] = 0; |
| buf[1] = 0; |
| |
| for (fpreg = 7; fpreg >= 0; fpreg--) |
| { |
| int tag = (ftag >> (fpreg * 2)) & 3; |
| |
| if (tag != 3) |
| buf[0] |= (1 << fpreg); |
| } |
| } |
| memcpy (FXSAVE_ADDR (fxsave, i), buf, 2); |
| } |
| else |
| regcache_collect (i, FXSAVE_ADDR (fxsave, i)); |
| } |
| } |
| |
| /* Recreate the FTW (tag word) valid bits from the 80-bit FP data in |
| *RAW. */ |
| |
| static int |
| i387_tag (unsigned char *raw) |
| { |
| int integer; |
| unsigned int exponent; |
| unsigned long fraction[2]; |
| |
| integer = raw[7] & 0x80; |
| exponent = (((raw[9] & 0x7f) << 8) | raw[8]); |
| fraction[0] = ((raw[3] << 24) | (raw[2] << 16) | (raw[1] << 8) | raw[0]); |
| fraction[1] = (((raw[7] & 0x7f) << 24) | (raw[6] << 16) |
| | (raw[5] << 8) | raw[4]); |
| |
| if (exponent == 0x7fff) |
| { |
| /* Special. */ |
| return (2); |
| } |
| else if (exponent == 0x0000) |
| { |
| if (fraction[0] == 0x0000 && fraction[1] == 0x0000 && !integer) |
| { |
| /* Zero. */ |
| return (1); |
| } |
| else |
| { |
| /* Special. */ |
| return (2); |
| } |
| } |
| else |
| { |
| if (integer) |
| { |
| /* Valid. */ |
| return (0); |
| } |
| else |
| { |
| /* Special. */ |
| return (2); |
| } |
| } |
| } |