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zydis
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Merged internal encoder AVX/REX structs 

- It was pretty redundant before
  - Required unnecessary routing logic
  - Minor decrease of required stack memory
- Added `ZydisEmitMVEX` and generally more MVEX support
This commit is contained in:
Joel Höner 2017-08-03 02:04:39 +02:00
parent 9437e89006
commit c0fd657f15
1 changed files with 109 additions and 172 deletions
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281
src/Encoder.c
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@ -77,65 +77,28 @@ typedef struct ZydisRawInstruction_
} imms[2];
struct
{
// REX bits
uint8_t W;
uint8_t R;
uint8_t X;
uint8_t B;
} rex;
struct
{
uint8_t R;
uint8_t X;
uint8_t B;
uint8_t m_mmmm;
uint8_t W;
uint8_t vvvv;
uint8_t L;
uint8_t pp;
} xop;
struct
{
uint8_t R;
uint8_t X;
uint8_t B;
uint8_t m_mmmm;
uint8_t W;
uint8_t vvvv;
uint8_t L;
uint8_t pp;
} vex;
struct
{
uint8_t R;
uint8_t X;
uint8_t B;
uint8_t R2;
// XOP/VEX bits
uint8_t mm;
uint8_t W;
uint8_t vvvv;
uint8_t L;
uint8_t pp;
// EVEX/MVEX bits
uint8_t R2;
uint8_t z;
uint8_t L2;
uint8_t L;
uint8_t b;
uint8_t V2;
uint8_t aaa;
} evex;
struct
{
uint8_t R;
uint8_t X;
uint8_t B;
uint8_t R2;
uint8_t mmmm;
uint8_t W;
uint8_t vvvv;
uint8_t pp;
uint8_t E;
uint8_t mask; // `.aaa` / `.kkk`
uint8_t SSS;
uint8_t V2;
uint8_t kkk;
} mvex;
uint8_t E;
} bits;
struct
{
uint8_t mod;
@ -265,10 +228,10 @@ static ZydisStatus ZydisEmitREX(ZydisEncoderContext* ctx)
ZYDIS_CHECK(ZydisEmitByte(
ctx,
0x40 |
(ctx->raw.rex.W & 0x01) << 3 |
(ctx->raw.rex.R & 0x01) << 2 |
(ctx->raw.rex.X & 0x01) << 1 |
(ctx->raw.rex.B & 0x01) << 0
(ctx->raw.bits.W & 0x01) << 3 |
(ctx->raw.bits.R & 0x01) << 2 |
(ctx->raw.bits.X & 0x01) << 1 |
(ctx->raw.bits.B & 0x01) << 0
));
return ZYDIS_STATUS_SUCCESS;
}
@ -278,18 +241,16 @@ static ZydisStatus ZydisEmitVEX(ZydisEncoderContext* ctx)
ZYDIS_ASSERT(ctx);
// Can we use short 2-byte VEX encoding?
if (ctx->raw.vex.X == 0 &&
ctx->raw.vex.B == 0 &&
ctx->raw.vex.W == 0 &&
ctx->raw.vex.m_mmmm == 1)
if (ctx->raw.bits.X == 0 && ctx->raw.bits.B == 0 &&
ctx->raw.bits.W == 0 && ctx->raw.bits.mm == 1)
{
ZYDIS_CHECK(ZydisEmitByte(ctx, 0xC5));
ZYDIS_CHECK(ZydisEmitByte(
ctx,
(~ctx->raw.vex.R & 0x01) << 7 |
(~ctx->raw.vex.vvvv & 0x0F) << 3 |
( ctx->raw.vex.L & 0x01) << 2 |
( ctx->raw.vex.pp & 0x03) << 0
(~ctx->raw.bits.R & 0x01) << 7 |
(~ctx->raw.bits.vvvv & 0x0F) << 3 |
( ctx->raw.bits.L & 0x01) << 2 |
( ctx->raw.bits.pp & 0x03) << 0
));
}
// Nope, use 3-byte VEX.
@ -298,17 +259,17 @@ static ZydisStatus ZydisEmitVEX(ZydisEncoderContext* ctx)
ZYDIS_CHECK(ZydisEmitByte(ctx, 0xC4));
ZYDIS_CHECK(ZydisEmitByte(
ctx,
(~ctx->raw.vex.R & 0x01) << 7 |
(~ctx->raw.vex.X & 0x01) << 6 |
(~ctx->raw.vex.B & 0x01) << 5 |
( ctx->raw.vex.m_mmmm & 0x1F) << 0
(~ctx->raw.bits.R & 0x01) << 7 |
(~ctx->raw.bits.X & 0x01) << 6 |
(~ctx->raw.bits.B & 0x01) << 5 |
( ctx->raw.bits.mm & 0x1F) << 0
));
ZYDIS_CHECK(ZydisEmitByte(
ctx,
( ctx->raw.vex.W & 0x01) << 7 |
(~ctx->raw.vex.vvvv & 0x0F) << 3 |
( ctx->raw.vex.L & 0x01) << 2 |
( ctx->raw.vex.pp & 0x03) << 0
( ctx->raw.bits.W & 0x01) << 7 |
(~ctx->raw.bits.vvvv & 0x0F) << 3 |
( ctx->raw.bits.L & 0x01) << 2 |
( ctx->raw.bits.pp & 0x03) << 0
));
}
@ -321,26 +282,54 @@ static ZydisStatus ZydisEmitEVEX(ZydisEncoderContext* ctx)
ZYDIS_CHECK(ZydisEmitByte(ctx, 0x62));
ZYDIS_CHECK(ZydisEmitByte(
ctx,
(ctx->raw.evex.R & 0x01) << 7 |
(ctx->raw.evex.X & 0x01) << 6 |
(ctx->raw.evex.B & 0x01) << 5 |
(ctx->raw.evex.R2 & 0x01) << 4 |
(ctx->raw.evex.mm & 0x03) << 0
(ctx->raw.bits.R & 0x01) << 7 |
(ctx->raw.bits.X & 0x01) << 6 |
(ctx->raw.bits.B & 0x01) << 5 |
(ctx->raw.bits.R2 & 0x01) << 4 |
(ctx->raw.bits.mm & 0x03) << 0
));
ZYDIS_CHECK(ZydisEmitByte(
ctx,
(ctx->raw.evex.W & 0x01) << 7 |
(ctx->raw.evex.vvvv & 0x0F) << 3 |
(ctx->raw.evex.pp & 0x03) << 0
(ctx->raw.bits.W & 0x01) << 7 |
(ctx->raw.bits.vvvv & 0x0F) << 3 |
(ctx->raw.bits.pp & 0x03) << 0
));
ZYDIS_CHECK(ZydisEmitByte(
ctx,
(ctx->raw.evex.z & 0x01) << 7 |
(ctx->raw.evex.L2 & 0x01) << 6 |
(ctx->raw.evex.L & 0x01) << 5 |
(ctx->raw.evex.b & 0x01) << 4 |
(ctx->raw.evex.V2 & 0x01) << 3 |
(ctx->raw.evex.aaa & 0x07) << 0
(ctx->raw.bits.z & 0x01) << 7 |
(ctx->raw.bits.L2 & 0x01) << 6 |
(ctx->raw.bits.L & 0x01) << 5 |
(ctx->raw.bits.b & 0x01) << 4 |
(ctx->raw.bits.V2 & 0x01) << 3 |
(ctx->raw.bits.mask & 0x07) << 0
));
return ZYDIS_STATUS_SUCCESS;
}
static ZydisStatus ZydisEmitMVEX(ZydisEncoderContext* ctx)
{
ZYDIS_ASSERT(ctx);
ZYDIS_CHECK(ZydisEmitByte(ctx, 0x62));
ZYDIS_CHECK(ZydisEmitByte(
ctx,
(ctx->raw.bits.R & 0x01) << 7 |
(ctx->raw.bits.X & 0x01) << 6 |
(ctx->raw.bits.B & 0x01) << 5 |
(ctx->raw.bits.R2 & 0x01) << 4 |
(ctx->raw.bits.mm & 0x0F) << 0
));
ZYDIS_CHECK(ZydisEmitByte(
ctx,
(ctx->raw.bits.W & 0x01) << 7 |
(ctx->raw.bits.vvvv & 0x0F) << 3 |
(ctx->raw.bits.pp & 0x03) << 0
));
ZYDIS_CHECK(ZydisEmitByte(
ctx,
(ctx->raw.bits.E & 0x01) << 7 |
(ctx->raw.bits.SSS & 0x07) << 4 |
(ctx->raw.bits.V2 & 0x01) << 3 |
(ctx->raw.bits.mask & 0x07) << 0
));
return ZYDIS_STATUS_SUCCESS;
}
@ -351,17 +340,17 @@ static ZydisStatus ZydisEmitXOP(ZydisEncoderContext* ctx)
ZYDIS_CHECK(ZydisEmitByte(ctx, 0x8F));
ZYDIS_CHECK(ZydisEmitByte(
ctx,
(ctx->raw.xop.R & 0x01) << 7 |
(ctx->raw.xop.X & 0x01) << 6 |
(ctx->raw.xop.B & 0x01) << 5 |
(ctx->raw.xop.m_mmmm & 0x1F) << 0
(ctx->raw.bits.R & 0x01) << 7 |
(ctx->raw.bits.X & 0x01) << 6 |
(ctx->raw.bits.B & 0x01) << 5 |
(ctx->raw.bits.mm & 0x1F) << 0
));
ZYDIS_CHECK(ZydisEmitByte(
ctx,
(ctx->raw.xop.W & 0x01) << 7 |
(ctx->raw.xop.vvvv & 0x0F) << 3 |
(ctx->raw.xop.L & 0x01) << 2 |
(ctx->raw.xop.pp & 0x03) << 0
(ctx->raw.bits.W & 0x01) << 7 |
(ctx->raw.bits.vvvv & 0x0F) << 3 |
(ctx->raw.bits.L & 0x01) << 2 |
(ctx->raw.bits.pp & 0x03) << 0
));
return ZYDIS_STATUS_SUCCESS;
}
@ -689,18 +678,19 @@ static ZydisStatus ZydisPrepareOpcode(ZydisEncoderContext* ctx, const ZydisInstr
}
break;
case ZYDIS_INSTRUCTION_ENCODING_VEX:
ctx->raw.vex.m_mmmm = match->insn->opcodeMap;
ZYDIS_ASSERT(ctx->raw.vex.m_mmmm <= 0x03);
ctx->raw.bits.mm = match->insn->opcodeMap;
ZYDIS_ASSERT(ctx->raw.bits.mm <= 0x03);
break;
case ZYDIS_INSTRUCTION_ENCODING_EVEX:
ctx->raw.evex.mm = match->insn->opcodeMap;
ZYDIS_ASSERT(ctx->raw.evex.mm <= 0x03);
case ZYDIS_INSTRUCTION_ENCODING_MVEX:
ctx->raw.bits.mm = match->insn->opcodeMap;
ZYDIS_ASSERT(ctx->raw.bits.mm <= 0x03);
break;
case ZYDIS_INSTRUCTION_ENCODING_XOP:
ctx->raw.xop.m_mmmm =
ctx->raw.bits.mm =
match->insn->opcodeMap - ZYDIS_OPCODE_MAP_XOP8 + 0x08;
ZYDIS_ASSERT(ctx->raw.xop.m_mmmm >= 0x08);
ZYDIS_ASSERT(ctx->raw.xop.m_mmmm <= 0x0B);
ZYDIS_ASSERT(ctx->raw.bits.mm >= 0x08);
ZYDIS_ASSERT(ctx->raw.bits.mm <= 0x0B);
break;
default:
ZYDIS_UNREACHABLE;
@ -731,57 +721,18 @@ static ZydisStatus ZydisPrepareRegOperand(ZydisEncoderContext* ctx,
// No top bit? Quick exit.
if (!topBit) return ZYDIS_STATUS_SUCCESS;
switch (ctx->req->encoding)
if ((ctx->req->encoding == ZYDIS_INSTRUCTION_ENCODING_DEFAULT ||
ctx->req->encoding == ZYDIS_INSTRUCTION_ENCODING_3DNOW) && topBit)
{
case ZYDIS_INSTRUCTION_ENCODING_DEFAULT:
case ZYDIS_INSTRUCTION_ENCODING_3DNOW:
switch (topBitDst)
{
case 'B': ctx->raw.rex.B = topBit; break;
case 'R': ctx->raw.rex.R = topBit; break;
case 'X': ctx->raw.rex.X = topBit; break;
default: ZYDIS_UNREACHABLE;
}
if (topBit) ctx->raw.derivedAttrs |= ZYDIS_ATTRIB_HAS_REX;
break;
case ZYDIS_INSTRUCTION_ENCODING_VEX:
switch (topBitDst)
{
case 'B': ctx->raw.vex.B = topBit; break;
case 'R': ctx->raw.vex.R = topBit; break;
case 'X': ctx->raw.vex.X = topBit; break;
default: ZYDIS_UNREACHABLE;
}
break;
case ZYDIS_INSTRUCTION_ENCODING_XOP:
switch (topBitDst)
{
case 'B': ctx->raw.xop.B = topBit; break;
case 'R': ctx->raw.xop.R = topBit; break;
case 'X': ctx->raw.xop.X = topBit; break;
default: ZYDIS_UNREACHABLE;
}
break;
case ZYDIS_INSTRUCTION_ENCODING_EVEX:
switch (topBitDst)
{
case 'B': ctx->raw.evex.B = topBit; break;
case 'R': ctx->raw.evex.R = topBit; break;
case 'X': ctx->raw.evex.X = topBit; break;
default: ZYDIS_UNREACHABLE;
}
break;
case ZYDIS_INSTRUCTION_ENCODING_MVEX:
switch (topBitDst)
{
case 'B': ctx->raw.mvex.B = topBit; break;
case 'R': ctx->raw.mvex.R = topBit; break;
case 'X': ctx->raw.mvex.X = topBit; break;
default: ZYDIS_UNREACHABLE;
}
break;
default:
return ZYDIS_STATUS_IMPOSSIBLE_INSTRUCTION; // TODO
ctx->raw.derivedAttrs |= ZYDIS_ATTRIB_HAS_REX;
}
switch (topBitDst)
{
case 'B': ctx->raw.bits.B = topBit; break;
case 'R': ctx->raw.bits.R = topBit; break;
case 'X': ctx->raw.bits.X = topBit; break;
default: ZYDIS_UNREACHABLE;
}
return ZYDIS_STATUS_SUCCESS;
@ -1008,26 +959,20 @@ static ZydisStatus ZydisPrepareOperand(ZydisEncoderContext* ctx,
int16_t reg = ZydisRegisterGetId(reqOperand->reg);
if (reg == -1) return ZYDIS_STATUS_INVALID_PARAMETER;
ctx->raw.opcode += reg & 0x07;
ctx->raw.rex.B = (reg & 0x08) >> 3;
if (ctx->raw.rex.B) ctx->raw.derivedAttrs |= ZYDIS_ATTRIB_HAS_REX;
ctx->raw.bits.B = (reg & 0x08) >> 3;
if (ctx->raw.bits.B) ctx->raw.derivedAttrs |= ZYDIS_ATTRIB_HAS_REX;
break;
}
case ZYDIS_OPERAND_ENCODING_NDSNDD:
{
int16_t reg = ZydisRegisterGetId(reqOperand->reg);
if (reg == -1) return ZYDIS_STATUS_INVALID_PARAMETER;
ctx->raw.vex.vvvv = ctx->raw.xop.vvvv = ctx->raw.evex.vvvv = reg & 0x0F;
ctx->raw.bits.vvvv = ctx->raw.bits.vvvv = ctx->raw.bits.vvvv = reg & 0x0F;
break;
}
case ZYDIS_OPERAND_ENCODING_MASK:
{
uint8_t regId = reqOperand->reg - ZYDIS_REGISTER_K0;
switch (match->insn->encoding)
{
case ZYDIS_INSTRUCTION_ENCODING_EVEX: ctx->raw.evex.aaa = regId; break;
case ZYDIS_INSTRUCTION_ENCODING_MVEX: ctx->raw.mvex.kkk = regId; break;
default: ZYDIS_UNREACHABLE;
}
ctx->raw.bits.mask = reqOperand->reg - ZYDIS_REGISTER_K0;
} break;
case ZYDIS_OPERAND_ENCODING_IS4:
{
@ -1085,14 +1030,11 @@ static void ZydisPrepareMandatoryPrefixes(ZydisEncoderContext* ctx,
case ZYDIS_INSTRUCTION_ENCODING_3DNOW:
ctx->raw.mandatoryPrefix = prefix;
break;
case ZYDIS_INSTRUCTION_ENCODING_VEX:
ctx->raw.vex.pp = prefix;
break;
case ZYDIS_INSTRUCTION_ENCODING_EVEX:
ctx->raw.evex.pp = prefix;
break;
case ZYDIS_INSTRUCTION_ENCODING_XOP:
ctx->raw.xop.pp = prefix;
case ZYDIS_INSTRUCTION_ENCODING_VEX:
case ZYDIS_INSTRUCTION_ENCODING_EVEX:
case ZYDIS_INSTRUCTION_ENCODING_MVEX:
ctx->raw.bits.pp = prefix;
break;
default:
ZYDIS_UNREACHABLE;
@ -1481,15 +1423,9 @@ ZydisStatus ZydisEncoderEncodeInstruction(void* buffer, size_t* bufferLen,
// TODO: Check compatibility of requested prefixes to found instruction.
// Prepare prefix bits.
ctx.raw.evex.B = match.insn->evexB;
ctx.raw.evex.L = match.insn->vectorLength & 0x01;
ctx.raw.evex.L2 = match.insn->vectorLength & 0x02;
ctx.raw.vex.L = match.insn->vectorLength & 0x01;
if (match.insn->rexW)
{
ctx.raw.rex.W = 1;
ctx.raw.derivedAttrs |= ZYDIS_ATTRIB_HAS_REX;
}
ctx.raw.bits.B = match.insn->evexB;
ctx.raw.bits.L = match.insn->vectorLength & 0x01;
ctx.raw.bits.L2 = match.insn->vectorLength & 0x02;
ZydisPrepareMandatoryPrefixes(&ctx, &match);
// Prepare opcode.
@ -1511,6 +1447,7 @@ ZydisStatus ZydisEncoderEncodeInstruction(void* buffer, size_t* bufferLen,
switch (match.insn->encoding)
{
case ZYDIS_INSTRUCTION_ENCODING_MVEX: ZYDIS_CHECK(ZydisEmitMVEX(&ctx)); break;
case ZYDIS_INSTRUCTION_ENCODING_EVEX: ZYDIS_CHECK(ZydisEmitEVEX(&ctx)); break;
case ZYDIS_INSTRUCTION_ENCODING_VEX: ZYDIS_CHECK(ZydisEmitVEX (&ctx)); break;
case ZYDIS_INSTRUCTION_ENCODING_XOP: ZYDIS_CHECK(ZydisEmitXOP (&ctx)); break;