Submition of i386.record.floating.point.patch

paawan oza
2009-06-01T14:55:09Z

Hi,

I am sorry for the inconvenience caused last time, during patch submition.
this time I am trying to post everything in email body.

******************************************************
ChangeLog:
******************************************************
Current: gdb-6.8.50.20090531
2009-05-31 Oza <paawan1982@yahoo.com>

* i386-tdep.c: Support for floating point recording.
* i386-tdep.h: floating point registers enumaration added.
-------------------------------------------------------

******************************************************
README:
******************************************************
Patch description:

-> Provides floating point support for i386 (reversible debugging:record-replay)
-> previously gdb was not recording floating point registers, now all the floating point registers which are likely to be changed by floating point instructions, are recorded and replayed.
-> the patch intends to provide the full support for all i386 floating point instructions.
---------------------------------------------------------

******************************************************
Patch:i386-record-floats.patch
******************************************************
diff -urN gdb.orig/i386-tdep.c gdb.new/i386-tdep.c
--- gdb.orig/i386-tdep.c 2009-05-29 17:08:40.000000000 -0400
+++ gdb.new/i386-tdep.c 2009-06-01 20:02:23.000000000 -0400
@@ -543,6 +543,9 @@
/* The maximum number of saved registers. This should include all
registers mentioned above, and %eip. */
#define I386_NUM_SAVED_REGS I386_NUM_GREGS
+#define I386_SAVE_FPU_REGS 0xFFFD
+#define I386_SAVE_FPU_ENV 0xFFFE
+#define I386_SAVE_FPU_ENV_REG_STACK 0xFFFF

struct i386_frame_cache
{
@@ -2985,6 +2988,54 @@
return 0;
}

+/* Record the value of floating point registers which will be changed by the current instruction
+ to "record_arch_list".
+ return -1 if something is wrong. */
+
+static int i386_record_floats(struct i386_record_s *ir, uint32_t iregnum)
+{
+ int i;
+
+ /* Oza : push/pop of fpu stack is going to happen
+ currently we store st0-st7 registers, but we need not store all registers all the time.
+ using fstatus, we use 11-13 bits which gives us stack top and hence we optimize our storage. */
+ if (I386_SAVE_FPU_REGS == iregnum)
+ {
+ for (i=I386_ST0_REGNUM;i<=I386_ST7_REGNUM;i++)
+ {
+ if (record_arch_list_add_reg (ir->regcache,i))
+ return -1;
+ }
+ }
+ else if (I386_SAVE_FPU_ENV == iregnum)
+ {
+ for (i=I386_FCTRL;i<=I386_FOP;i++)
+ {
+ if (record_arch_list_add_reg (ir->regcache,i))
+ return -1;
+ }
+ }
+ else if (I386_SAVE_FPU_ENV_REG_STACK == iregnum)
+ {
+ for (i=I386_ST0_REGNUM;i<=I386_FOP;i++)
+ {
+ if (record_arch_list_add_reg (ir->regcache,i))
+ return -1;
+ }
+ }
+ else if (iregnum >= I386_ST0_REGNUM && iregnum <= I386_FOP)
+ {
+ if (record_arch_list_add_reg (ir->regcache,iregnum))
+ return -1;
+ }
+ else
+ {
+ /* param Error */
+ return -1;
+ }
+ return 0;
+}
+
/* Parse the current instruction and record the values of the registers and
memory that will be changed in current instruction to "record_arch_list".
Return -1 if something wrong. */
@@ -4035,7 +4086,6 @@
break;

/* floats */
- /* It just record the memory change of instrcution. */
case 0xd8:
case 0xd9:
case 0xda:
@@ -4056,39 +4106,49 @@
return -1;
switch (ir.reg)
{
- case 0x00:
- case 0x01:
case 0x02:
- case 0x03:
+ case 0x12:
+ case 0x22:
+ case 0x32:
+ /* for FCOM, FICOM nothing to do */
+ break;
+ case 0x03:
+ case 0x13:
+ case 0x23:
+ case 0x33:
+ /* FCOMP, FICOMP pop FPU stack, store all */
+ if (i386_record_floats(&ir, I386_SAVE_FPU_REGS))
+ return -1;
+ break;
+ case 0x00:
+ case 0x01:
case 0x04:
case 0x05:
case 0x06:
case 0x07:
case 0x10:
- case 0x11:
- case 0x12:
- case 0x13:
+ case 0x11:
case 0x14:
case 0x15:
case 0x16:
case 0x17:
case 0x20:
case 0x21:
- case 0x22:
- case 0x23:
case 0x24:
case 0x25:
case 0x26:
case 0x27:
case 0x30:
case 0x31:
- case 0x32:
- case 0x33:
case 0x34:
case 0x35:
case 0x36:
case 0x37:
- break;
+ /* FADD, FMUL, FSUB, FSUBR, FDIV, FDIVR, FIADD, FIMUL, FISUB, FISUBR, FIDIV, FIDIVR
+ ModR/M.reg is an extension of code, always affects st(0) register */
+ if (i386_record_floats(&ir, I386_ST0_REGNUM))
+ return -1;
+ break;
case 0x08:
case 0x0a:
case 0x0b:
@@ -4096,6 +4156,7 @@
case 0x19:
case 0x1a:
case 0x1b:
+ case 0x1d:
case 0x28:
case 0x29:
case 0x2a:
@@ -4103,11 +4164,16 @@
case 0x38:
case 0x39:
case 0x3a:
- case 0x3b:
+ case 0x3b:
+ case 0x3c:
+ case 0x3d:
switch (ir.reg & 7)
{
case 0:
- break;
+ /* FLD, FILD */
+ if (i386_record_floats(&ir, I386_SAVE_FPU_REGS))
+ return -1;
+ break;
case 1:
switch (ir.reg >> 4)
{
@@ -4120,6 +4186,7 @@
return -1;
break;
case 3:
+ break;
default:
if (record_arch_list_add_mem (addr, 2))
return -1;
@@ -4130,15 +4197,42 @@
switch (ir.reg >> 4)
{
case 0:
+ if (record_arch_list_add_mem (addr, 4))
+ return -1;
+ if (3 == (ir.reg & 7))
+ {
+ /* FSTP m32fp */
+ if (i386_record_floats(&ir, I386_SAVE_FPU_REGS))
+ return -1;
+ }
+ break;
case 1:
if (record_arch_list_add_mem (addr, 4))
return -1;
+ if ((3 == (ir.reg & 7)) || (5 == (ir.reg & 7)) || (7 == (ir.reg & 7)))
+ {
+ /* FSTP */
+ if (i386_record_floats(&ir, I386_SAVE_FPU_REGS))
+ return -1;
+ }
break;
case 2:
if (record_arch_list_add_mem (addr, 8))
return -1;
+ if (3 == (ir.reg & 7))
+ {
+ /* FSTP m64fp */
+ if (i386_record_floats(&ir, I386_SAVE_FPU_REGS))
+ return -1;
+ }
break;
case 3:
+ if ((3 <= (ir.reg & 7)) && (6 <= (ir.reg & 7)))
+ {
+ /* FISTP, FBLD, FILD, FBSTP */
+ if (i386_record_floats(&ir, I386_SAVE_FPU_REGS))
+ return -1;
+ }
default:
if (record_arch_list_add_mem (addr, 2))
return -1;
@@ -4147,54 +4241,71 @@
break;
}
break;
- case 0x0c:
- case 0x0d:
- case 0x1d:
- case 0x2c:
- case 0x3c:
- case 0x3d:
- break;
- case 0x0e:
+ case 0x0c:
+ /* FLDENV */
+ if (i386_record_floats(&ir, I386_SAVE_FPU_ENV_REG_STACK))
+ return -1;
+ break;
+ case 0x0d:
+ /* FLDCW */
+ if (i386_record_floats(&ir, I386_FCTRL))
+ return -1;
+ break;
+ case 0x2c:
+ /* FRTSTOR */
+ if (i386_record_floats(&ir, I386_SAVE_FPU_ENV_REG_STACK))
+ return -1;
+ break;
+ case 0x0e:
if (ir.dflag)
{
- if (record_arch_list_add_mem (addr, 28))
- return -1;
+ if (record_arch_list_add_mem (addr, 28))
+ return -1;
}
else
{
- if (record_arch_list_add_mem (addr, 14))
- return -1;
+ if (record_arch_list_add_mem (addr, 14))
+ return -1;
}
break;
- case 0x0f:
- case 0x2f:
+ case 0x0f:
+ case 0x2f:
if (record_arch_list_add_mem (addr, 2))
return -1;
break;
- case 0x1f:
- case 0x3e:
+ case 0x1f:
+ case 0x3e:
if (record_arch_list_add_mem (addr, 10))
return -1;
+ /* FSTP, FBSTP */
+ if (i386_record_floats(&ir, I386_SAVE_FPU_REGS))
+ return -1;
break;
- case 0x2e:
+ case 0x2e:
if (ir.dflag)
{
- if (record_arch_list_add_mem (addr, 28))
- return -1;
- addr += 28;
+ if (record_arch_list_add_mem (addr, 28))
+ return -1;
+ addr += 28;
}
else
{
- if (record_arch_list_add_mem (addr, 14))
- return -1;
- addr += 14;
+ if (record_arch_list_add_mem (addr, 14))
+ return -1;
+ addr += 14;
}
if (record_arch_list_add_mem (addr, 80))
return -1;
+ /* FSAVE */
+ if (i386_record_floats(&ir, I386_SAVE_FPU_ENV_REG_STACK))
+ return -1;
break;
- case 0x3f:
+ case 0x3f:
if (record_arch_list_add_mem (addr, 8))
return -1;
+ /* FISTP */
+ if (i386_record_floats(&ir, I386_SAVE_FPU_REGS))
+ return -1;
break;
default:
ir.addr -= 2;
@@ -4202,9 +4313,180 @@
goto no_support;
break;
}
- }
+ }
+ /* opcode is an extension of modR/M byte */
+ else
+ {
+ switch (opcode)
+ {
+ case 0xd8:
+ if (i386_record_floats(&ir, I386_ST0_REGNUM))
+ return -1;
+ break;
+ case 0xd9:
+ if (0x0c == (ir.modrm >> 4))
+ {
+ if ((ir.modrm & 0x0f) <= 7)
+ {
+ if (i386_record_floats(&ir, I386_SAVE_FPU_REGS))
+ return -1;
+ }
+ else
+ {
+ if (i386_record_floats(&ir, I386_ST0_REGNUM))
+ return -1;
+ /* if only st(0) is changing, then we have already recorded */
+ if ((ir.modrm & 0x0f) - 0x08)
+ {
+ if (i386_record_floats(&ir, I386_ST0_REGNUM + ((ir.modrm & 0x0f) - 0x08)))
+ return -1;
+ }
+ }
+ }
+ else
+ {
+ switch(ir.modrm)
+ {
+ case 0xe0:
+ case 0xe1:
+ case 0xf0:
+ case 0xf5:
+ case 0xf8:
+ case 0xfa:
+ case 0xfc:
+ case 0xfe:
+ case 0xff:
+ if (i386_record_floats(&ir, I386_ST0_REGNUM))
+ return -1;
+ break;
+ case 0xf1:
+ case 0xf2:
+ case 0xf3:
+ case 0xf4:
+ case 0xf6:
+ case 0xf7:
+ case 0xe8:
+ case 0xe9:
+ case 0xea:
+ case 0xeb:
+ case 0xec:
+ case 0xed:
+ case 0xee:
+ case 0xf9:
+ case 0xfb:
+ if (i386_record_floats(&ir, I386_SAVE_FPU_REGS))
+ return -1;
+ break;
+ case 0xfd:
+ if (i386_record_floats(&ir, I386_ST0_REGNUM))
+ return -1;
+ if (i386_record_floats(&ir, I386_ST1_REGNUM))
+ return -1;
+ break;
+ }
+ }
+ break;
+ case 0xda:
+ if (0xe9 == ir.modrm)
+ {
+ if (i386_record_floats(&ir, I386_SAVE_FPU_REGS))
+ return -1;
+ }
+ else if ((0x0c == ir.modrm >> 4) || (0x0d == ir.modrm >> 4))
+ {
+ if (i386_record_floats(&ir, I386_ST0_REGNUM))
+ return -1;
+ if (((ir.modrm & 0x0f) > 0) && ((ir.modrm & 0x0f) <= 7))
+ {
+ if (i386_record_floats(&ir, I386_ST0_REGNUM + (ir.modrm & 0x0f)))
+ return -1;
+ }
+ else if ((ir.modrm & 0x0f) - 0x08)
+ {
+ if (i386_record_floats(&ir, I386_ST0_REGNUM + ((ir.modrm & 0x0f) - 0x08)))
+ return -1;
+ }
+ }
+ break;
+ case 0xdb:
+ if (0xe3 == ir.modrm)
+ {
+ if (i386_record_floats(&ir, I386_SAVE_FPU_ENV))
+ return -1;
+ }
+ else if ((0x0c == ir.modrm >> 4) || (0x0d == ir.modrm >> 4))
+ {
+ if (i386_record_floats(&ir, I386_ST0_REGNUM))
+ return -1;
+ if (((ir.modrm & 0x0f) > 0) && ((ir.modrm & 0x0f) <= 7))
+ {
+ if (i386_record_floats(&ir, I386_ST0_REGNUM + (ir.modrm & 0x0f)))
+ return -1;
+ }
+ else if ((ir.modrm & 0x0f) - 0x08)
+ {
+ if (i386_record_floats(&ir, I386_ST0_REGNUM + ((ir.modrm & 0x0f) - 0x08)))
+ return -1;
+ }
+ }
+ break;
+ case 0xdc:
+ if ((0x0c == ir.modrm >> 4) || (0x0d == ir.modrm >> 4) || (0x0f == ir.modrm >> 4))
+ {
+ if ((ir.modrm & 0x0f) <= 7)
+ {
+ if (i386_record_floats(&ir, I386_ST0_REGNUM + (ir.modrm & 0x0f)))
+ return -1;
+ }
+ else
+ {
+ if (i386_record_floats(&ir, I386_ST0_REGNUM + ((ir.modrm & 0x0f) - 0x08)))
+ return -1;
+ }
+ }
+ break;
+ case 0xdd:
+ if (0x0c == ir.modrm >> 4)
+ {
+ if (i386_record_floats(&ir,I386_FTAG))
+ return -1;
+ }
+ else if ((0x0d == ir.modrm >> 4) || (0x0e == ir.modrm >> 4))
+ {
+ if ((ir.modrm & 0x0f) <= 7)
+ {
+ if (i386_record_floats(&ir, I386_ST0_REGNUM + (ir.modrm & 0x0f)))
+ return -1;
+ }
+ else
+ {
+ if (i386_record_floats(&ir, I386_SAVE_FPU_REGS))
+ return -1;
+ }
+ }
+ break;
+ case 0xde:
+ if ((0x0c == ir.modrm >> 4) || (0x0e == ir.modrm >> 4) || (0x0f == ir.modrm >> 4) || (0xd9 == ir.modrm))
+ {
+ if (i386_record_floats(&ir, I386_SAVE_FPU_REGS))
+ return -1;
+ }
+ break;
+ case 0xdf:
+ if (0xe0 == ir.modrm)
+ {
+ if (record_arch_list_add_reg (ir.regcache, I386_EAX_REGNUM))
+ return -1;
+ }
+ else if ((0x0f == ir.modrm >> 4) || (0x0e == ir.modrm >> 4))
+ {
+ if (i386_record_floats(&ir, I386_SAVE_FPU_REGS))
+ return -1;
+ }
+ break;
+ }
+ }
break;
-
/* string ops */
/* movsS */
case 0xa4:
@@ -4623,10 +4905,17 @@
/* fwait */
/* XXX */
case 0x9b:
- printf_unfiltered (_("Process record doesn't support instruction "
- "fwait.\n"));
- ir.addr -= 1;
- goto no_support;
+ if (target_read_memory (ir.addr, &tmpu8, 1))
+ {
+ if (record_debug)
+ printf_unfiltered (_("Process record: error reading memory at "
+ "addr 0x%s len = 1.\n"),
+ paddr_nz (ir.addr));
+ return -1;
+ }
+ opcode = (uint32_t) tmpu8;
+ ir.addr++;
+ goto reswitch;
break;

/* int3 */
diff -urN gdb.orig/i386-tdep.h gdb.new/i386-tdep.h
--- gdb.orig/i386-tdep.h 2009-05-17 17:56:44.000000000 -0400
+++ gdb.new/i386-tdep.h 2009-05-31 16:33:14.000000000 -0400
@@ -145,7 +145,22 @@
I386_ES_REGNUM, /* %es */
I386_FS_REGNUM, /* %fs */
I386_GS_REGNUM, /* %gs */
- I386_ST0_REGNUM /* %st(0) */
+ I386_ST0_REGNUM, /* %st(0) */
+ I386_ST1_REGNUM, /* %st(1) */
+ I386_ST2_REGNUM, /* %st(2) */
+ I386_ST3_REGNUM, /* %st(3) */
+ I386_ST4_REGNUM, /* %st(4) */
+ I386_ST5_REGNUM, /* %st(5) */
+ I386_ST6_REGNUM, /* %st(6) */
+ I386_ST7_REGNUM, /* %st(7) */
+ I386_FCTRL, /* floating point env regs : FCTRL-FOP */
+ I386_FSTAT,
+ I386_FTAG,
+ I386_FISEG,
+ I386_FIOFF,
+ I386_FOSEG,
+ I386_FOOFF,
+ I386_FOP
};

#define I386_NUM_GREGS 16

*******************************************************
test-example which does basic verification for the patch.
*******************************************************

#include <stdio.h>
#include <math.h>

int main()
{
float no1,no2,no3,no4,no5,no6,no7;
double x = 100.345, y = 25.7789;
long double ldx = 88888888888888888888.88, ldy = 9999999999999999999.99;
float result,resultd,resultld;
no1 = 10.45;
no2 = 20.77;
no3 = 156.89874646;
no4 = 14.56;
no5 = 11.11;
no6 = 66.77;
no7 = 88.88;

result = no1 + no2 + no3 + no4 + no5 + no6 + no7;
printf("result is %f\n",result);

result = fmodf(no2,no1);
printf("result is %f\n",result);

resultd = fmod(x,y);
printf("result is %f\n",resultd);

resultld = fmodl(ldy,ldy);
printf("result is %f\n",resultld);

result = fabsf(no1);
printf("result is %f\n",result);

result = no3 / no4;
printf("result is %f\n",result);

result = no1 * no2 * no3 * no4;
printf("result is %f\n",result);

result = sin(30);
printf("result is %f\n",result);

result = cos(30);
printf("result is %f\n",result);

result = tan(30);
printf("result is %f\n",result);

result = atan(30);
printf("result is %f\n",result);

result = sqrt(no3);
printf("result is %f\n",result);

result = log10(no3);
printf("result is %f\n",result);

result = log(no3);
printf("result is %f\n",result);

result = exp10(no3);
printf("result is %f\n",result);

result = exp(no3);
printf("result is %f\n",result);

ldy = 88888888888888888888.88;
if (ldx == ldy)
ldy = 7777777777777777777777777777.777;
else
ldy = 666666666666666666666666666.666;

}

please send the review comments for the patch.

Regards,
Oza.