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Binary rewriting bugs fixed -- still segfault's with Unix benchmarkin…
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…g tool
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John Detter committed Jun 20, 2016
1 parent b495a41 commit c2a2e27
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Showing 2 changed files with 36 additions and 23 deletions.
57 changes: 35 additions & 22 deletions common/src/arch-x86.C
View file
Original file line number Diff line number Diff line change
Expand Up @@ -8211,6 +8211,12 @@ ia32_instruction& ia32_decode(unsigned int capa, const unsigned char* addr, ia32
return instruct;
}

// printf("PREFIXES(%d): ", instruct.size);

// int x;
// for(x = 0;x < instruct.size;x++)
// printf("%x ", addr[x]);

/* Skip the prefixes so that we don't decode them again */
addr = addr_orig + instruct.size;

Expand All @@ -8223,13 +8229,17 @@ ia32_instruction& ia32_decode(unsigned int capa, const unsigned char* addr, ia32
/* FPU decoding success. Return immediately */
return instruct;
}

/* Opcode decoding failed */
instruct.entry = NULL;
instruct.legacy_type = ILLEGAL;
return instruct;
}

// printf("OP(%d): ", instruct.size - x);

// for(;x < instruct.size;x++)
// printf("%x ", addr_orig[x]);

if(!gotit)
assert(!"Didn't find a valid instruction, however decode suceeded.");

Expand All @@ -8239,6 +8249,10 @@ ia32_instruction& ia32_decode(unsigned int capa, const unsigned char* addr, ia32
/* Do the operand decoding */
ia32_decode_operands(pref, *gotit, addr, instruct, instruct.mac);

// printf("OPERANDS(%d): ", instruct.size - x);
// for(;x < instruct.size;x++)
// printf("%x ", addr_orig[x]);

/* Decode the memory accesses if requested */
if(capa & IA32_DECODE_MEMACCESS)
{
Expand Down Expand Up @@ -8457,18 +8471,20 @@ ia32_instruction& ia32_decode(unsigned int capa, const unsigned char* addr, ia32
}

instruct.entry = gotit;

// printf("LEN: %d\n", instruct.size);
return instruct;
}

int ia32_decode_opcode(unsigned int capa, const unsigned char* addr,
ia32_instruction& instruct, ia32_entry** gotit_ret)
{
ia32_prefixes& pref = instruct.prf;
ia32_prefixes& pref = instruct.prf;
unsigned int table, nxtab, idx;
int sseidx = 0;
ia32_entry* gotit = NULL;
int condbits = 0;

#ifdef VEX_DEBUG
/* Dump the VEX header */
printf("IS VEX PRESENT? %s\n", pref.vex_present ? "YES" : "NO");
Expand All @@ -8491,7 +8507,7 @@ int ia32_decode_opcode(unsigned int capa, const unsigned char* addr,
}
#endif

/* Is there a VEX prefix for this instruction? */
/* Is there a VEX prefix for this instruction? */
if(pref.vex_present)
{
#ifdef VEX_PEDANTIC
Expand Down Expand Up @@ -8567,7 +8583,7 @@ int ia32_decode_opcode(unsigned int capa, const unsigned char* addr,
condbits = idx & 0x0F;
}

/* Find the correct entry in the tables */
/* Find the correct entry in the tables */
while(nxtab != t_done)
{
table = nxtab;
Expand Down Expand Up @@ -8756,11 +8772,11 @@ int ia32_decode_opcode(unsigned int capa, const unsigned char* addr,
case Grp2:
case Grp11:
/* leave table unchanged because operands are in not
defined in group map, unless this is an invalid index
into the group, in which case we need the instruction
to reflect its illegal status */
defined in group map, unless this is an invalid index
into the group, in which case we need the instruction
to reflect its illegal status */
if(groupMap[idx][reg].id == e_No_Entry)
gotit = &groupMap[idx][reg];
gotit = &groupMap[idx][reg];
nxtab = groupMap[idx][reg].otable;
assert(nxtab==t_done || nxtab==t_ill);
break;
Expand Down Expand Up @@ -8822,7 +8838,7 @@ int ia32_decode_opcode(unsigned int capa, const unsigned char* addr,
nxtab = t_done;
break;
case t_vexl:
/* This can have a vex prefix */
/* This can have a vex prefix */
if(!pref.vex_present)
{
/* If this instruction is valid without it, then it's fine */
Expand Down Expand Up @@ -8866,7 +8882,7 @@ int ia32_decode_opcode(unsigned int capa, const unsigned char* addr,
#ifdef VEX_DEBUG
fprintf(stderr, "VEXW ENTRY: VEXW%x\n", idx);
fprintf(stderr, "VEXW MAX ENTRY: VEXW%lx\n",
(sizeof(vexWMap) / sizeof(vexWMap[0])) - 1);
(sizeof(vexWMap) / sizeof(vexWMap[0])) - 1);
#endif

/* Set the current entry */
Expand Down Expand Up @@ -8919,7 +8935,7 @@ int ia32_decode_opcode(unsigned int capa, const unsigned char* addr,
{
printf("MISSING INSTRUCTION IN TABLE: %s\n",
(pref.vex_m_mmmm == 1 ? "twoByteMap" :
(pref.vex_m_mmmm == 2 ? "threeByteMap" : "threeByteMap2")));
(pref.vex_m_mmmm == 2 ? "threeByteMap" : "threeByteMap2")));
printf(" SSE_IDX: %d\n", sseidx);
}
#endif
Expand All @@ -8945,6 +8961,12 @@ int ia32_decode_opcode(unsigned int capa, const unsigned char* addr,
instruct.loc->opcode_position = pref.getCount();
}

/* make adjustments for instruction redefined in 64-bit mode */
if(mode_64)
{
ia32_translate_for_64(&gotit);
}

/* Set the condition bits if we need to */
if(capa & IA32_DECODE_CONDITION)
{
Expand All @@ -8953,17 +8975,9 @@ int ia32_decode_opcode(unsigned int capa, const unsigned char* addr,
instruct.cond->set(condbits);
}

/* make adjustments for instruction redefined in 64-bit mode */
if(mode_64)
{
ia32_translate_for_64(&gotit);
}

if(gotit_ret)
*gotit_ret = gotit;



return 0;
}

Expand Down Expand Up @@ -9883,8 +9897,8 @@ bool ia32_decode_prefixes(const unsigned char* addr, ia32_instruction& instruct)
ia32_prefixes& pref = instruct.prf;
ia32_locations* loc = instruct.loc;
/* Initilize the prefix */
pref.count = 0;
memset(pref.prfx, 0, 5);
pref.count = 0;
pref.opcode_prefix = 0;
bool in_prefix = true;

Expand Down Expand Up @@ -10231,7 +10245,6 @@ unsigned int ia32_emulate_old_type(ia32_instruction& instruct)
switch(pref.vex_type)
{
case VEX_TYPE_VEX2:
printf("HIT VEX2\n");
insnType |= PREFIX_AVX;
break;
case VEX_TYPE_VEX3:
Expand Down
2 changes: 1 addition & 1 deletion dyninstAPI/src/codegen-x86.C
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1322,7 +1322,7 @@ bool insnCodeGen::modifyDisp(signed long newDisp, instruction &insn, codeGen &ge
origInsn += pref_count;

/* Decode the opcode */
if(ia32_decode_opcode(/* capa*/0, origInsn, instruct, NULL))
if(ia32_decode_opcode(IA32_FULL_DECODER, origInsn, instruct, NULL))
assert(!"Couldn't decode opcode of already known instruction!\n");

/* Calculate the amount of opcode bytes */
Expand Down

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