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authorMark Kettenis <kettenis@gnu.org>2000-08-10 14:54:51 +0000
committerMark Kettenis <kettenis@gnu.org>2000-08-10 14:54:51 +0000
commite2890f080481667b088d9909e43295ad7e26e15e (patch)
tree62ae6d6e6fffbd35cd16dc21042393afef324768 /gdb/i387-nat.c
parent2e685b93dfef9012b6b1c25dc92e79a4b0a18dcc (diff)
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* i387-nat.h (i387_supply_fsave, i387_fill_fsave): Make extern.
(i387_supply_fxsave, i387_fill_fxsave): New prototypes. * i387-nat.c (i387_supply_fsave): Declare `val' as `unsigned int'. (fxsave_offset): New variable. (FXSAVE_ADDR): New macro. (i387_supply_fxsave, i387_fill_fxsave, i387_tag): New functions.
Diffstat (limited to 'gdb/i387-nat.c')
-rw-r--r--gdb/i387-nat.c211
1 files changed, 209 insertions, 2 deletions
diff --git a/gdb/i387-nat.c b/gdb/i387-nat.c
index 17e67b4..7698608 100644
--- a/gdb/i387-nat.c
+++ b/gdb/i387-nat.c
@@ -1,5 +1,5 @@
/* Native-dependent code for the i387.
- Copyright (C) 2000 Free Software Foundation, Inc.
+ Copyright 2000 Free Software Foundation, Inc.
This file is part of GDB.
@@ -71,7 +71,7 @@ i387_supply_fsave (char *fsave)
if (i >= FIRST_FPU_CTRL_REGNUM
&& i != FCOFF_REGNUM && i != FDOFF_REGNUM)
{
- unsigned val = *(unsigned short *) (FSAVE_ADDR (fsave, i));
+ unsigned int val = *(unsigned short *) (FSAVE_ADDR (fsave, i));
if (i == FOP_REGNUM)
{
@@ -123,3 +123,210 @@ i387_fill_fsave (char *fsave, int regno)
REGISTER_RAW_SIZE (i));
}
}
+
+
+/* At fxsave_offset[REGNO] you'll find the offset to the location in
+ the data structure used by the "fxsave" instruction where GDB
+ register REGNO 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, /* FCS_REGNUM (16 bits). */
+ 8, /* FCOFF_REGNUM. */
+ 20, /* FDS_REGNUM (16 bits). */
+ 16, /* FDOFF_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;
+
+ for (i = FP0_REGNUM; i <= MXCSR_REGNUM; i++)
+ {
+ /* Most of the FPU control registers occupy only 16 bits in
+ the fxsave area. Give those a special treatment. */
+ if (i >= FIRST_FPU_CTRL_REGNUM && i < XMM0_REGNUM
+ && i != FCOFF_REGNUM && i != FDOFF_REGNUM)
+ {
+ unsigned long val = *(unsigned short *) (FXSAVE_ADDR (fxsave, i));
+
+ if (i == FOP_REGNUM)
+ {
+ val &= ((1 << 11) - 1);
+ supply_register (i, (char *) &val);
+ }
+ 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;
+ unsigned long fstat;
+ int fpreg;
+ int top;
+
+ fstat = *(unsigned short *) (FXSAVE_ADDR (fxsave, FSTAT_REGNUM));
+ top = ((fstat >> 11) & 0x111);
+
+ for (fpreg = 7; fpreg >= 0; fpreg--)
+ {
+ int tag = 0x11;
+
+ if (val & (1 << fpreg))
+ {
+ int regnum = (fpreg + 8 - top) % 8 + FP0_REGNUM;
+ tag = i387_tag (FXSAVE_ADDR (fxsave, regnum));
+ }
+
+ ftag |= tag << (2 * fpreg);
+ }
+ supply_register (i, (char *) &ftag);
+ }
+ else
+ supply_register (i, (char *) &val);
+ }
+ else
+ supply_register (i, FXSAVE_ADDR (fxsave, i));
+ }
+}
+
+/* Fill register REGNO (if it is a floating-point or SSE register) in
+ *FXSAVE with the value in GDB's register array. If REGNO 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 regno)
+{
+ int i;
+
+ for (i = FP0_REGNUM; i <= MXCSR_REGNUM; i++)
+ if (regno == -1 || regno == i)
+ {
+ /* Most of the FPU control registers occupy only 16 bits in
+ the fxsave area. Give those a special treatment. */
+ if (i >= FIRST_FPU_CTRL_REGNUM && i < XMM0_REGNUM
+ && i != FCOFF_REGNUM && i != FDOFF_REGNUM)
+ {
+ if (i == FOP_REGNUM)
+ {
+ unsigned short oldval, newval;
+
+ /* The opcode occupies only 11 bits. */
+ oldval = (*(unsigned short *) (FXSAVE_ADDR (fxsave, i)));
+ newval = *(unsigned short *) &registers[REGISTER_BYTE (i)];
+ newval &= ((1 << 11) - 1);
+ newval |= oldval & ~((1 << 11) - 1);
+ memcpy (FXSAVE_ADDR (fxsave, i), &newval, 2);
+ }
+ else if (i == FTAG_REGNUM)
+ {
+ /* Converting back is much easier. */
+
+ unsigned char val = 0;
+ unsigned short ftag;
+ int fpreg;
+
+ ftag = *(unsigned short *) &registers[REGISTER_BYTE (i)];
+
+ for (fpreg = 7; fpreg >= 0; fpreg--)
+ {
+ int tag = (ftag >> (fpreg * 2)) & 0x11;
+
+ if (tag != 0x11)
+ val |= (1 << fpreg);
+ }
+
+ memcpy (FXSAVE_ADDR (fxsave, i), &val, 2);
+ }
+ else
+ memcpy (FXSAVE_ADDR (fxsave, i),
+ &registers[REGISTER_BYTE (i)], 2);
+ }
+ else
+ memcpy (FXSAVE_ADDR (fxsave, i), &registers[REGISTER_BYTE (i)],
+ REGISTER_RAW_SIZE (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 (0x10);
+ }
+ else if (exponent == 0x0000)
+ {
+ if (integer)
+ {
+ /* Valid. */
+ return (0x00);
+ }
+ else
+ {
+ /* Special. */
+ return (0x10);
+ }
+ }
+ else
+ {
+ if (fraction[0] == 0x0000 && fraction[1] == 0x0000 && !integer)
+ {
+ /* Zero. */
+ return (0x01);
+ }
+ else
+ {
+ /* Special. */
+ return (0x10);
+ }
+ }
+}