sourcemod/public/jit/x86/assembler-x86.h
David Anderson e69e9eddc7 Change float comparison operators to return false for NaN (bug 6107, r=ds).
--HG--
extra : rebase_source : a11c56fb23d6617545def3591ec6100dd143eb3e
2014-04-22 19:40:45 -07:00

978 lines
25 KiB
C++

/**
* vim: set ts=8 sts=2 sw=2 tw=99 et:
* =============================================================================
* SourcePawn JIT SDK
* Copyright (C) 2004-2008 AlliedModders LLC. All rights reserved.
* =============================================================================
*
* This program is free software; you can redistribute it and/or modify it under
* the terms of the GNU General Public License, version 3.0, as published by the
* Free Software Foundation.
*
* 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, see <http://www.gnu.org/licenses/>.
*
* As a special exception, AlliedModders LLC gives you permission to link the
* code of this program (as well as its derivative works) to "Half-Life 2," the
* "Source Engine," the "SourcePawn JIT," and any Game MODs that run on software
* by the Valve Corporation. You must obey the GNU General Public License in
* all respects for all other code used. Additionally, AlliedModders LLC grants
* this exception to all derivative works. AlliedModders LLC defines further
* exceptions, found in LICENSE.txt (as of this writing, version JULY-31-2007),
* or <http://www.sourcemod.net/license.php>.
*
* Version: $Id$
*/
#ifndef _include_sourcepawn_assembler_x86_h__
#define _include_sourcepawn_assembler_x86_h__
#include <assembler.h>
#include <am-vector.h>
#include <string.h>
struct Register
{
const char *name() const {
static const char *names[] = {
"eax", "ecx", "edx", "ebx", "esp", "ebp", "esi", "edi"
};
return names[code];
}
int code;
bool operator == (const Register &other) const {
return code == other.code;
}
bool operator != (const Register &other) const {
return code != other.code;
}
};
// X86 has an ancient FPU (called x87) which has a stack of registers
// numbered st0 through st7.
struct FpuRegister
{
const char *name() const {
static const char *names[] = {
"st0", "st1", "st2", "st3", "st4", "st5", "st6", "st7"
};
return names[code];
}
int code;
bool operator == (const FpuRegister &other) const {
return code == other.code;
}
bool operator != (const FpuRegister &other) const {
return code != other.code;
}
};
struct FloatRegister
{
const char *name() const {
static const char *names[] = {
"xmm0", "xmm1", "xmm2", "xmm3", "xmm4", "xmm5", "xmm6", "xmm7"
};
return names[code];
}
int code;
bool operator == (const FloatRegister &other) const {
return code == other.code;
}
bool operator != (const FloatRegister &other) const {
return code != other.code;
}
};
struct CPUFeatures
{
CPUFeatures()
{
memset(this, 0, sizeof(*this));
}
bool fpu;
bool mmx;
bool sse;
bool sse2;
bool sse3;
bool ssse3;
bool sse4_1;
bool sse4_2;
bool avx;
bool avx2;
};
const Register eax = { 0 };
const Register ecx = { 1 };
const Register edx = { 2 };
const Register ebx = { 3 };
const Register esp = { 4 };
const Register ebp = { 5 };
const Register esi = { 6 };
const Register edi = { 7 };
const Register r8_al = { 0 };
const Register r8_cl = { 1 };
const Register r8_dl = { 2 };
const Register r8_bl = { 3 };
const Register r8_ah = { 4 };
const Register r8_ch = { 5 };
const Register r8_dh = { 6 };
const Register r8_bh = { 7 };
const FpuRegister st0 = { 0 };
const FpuRegister st1 = { 1 };
const FpuRegister st2 = { 2 };
const FpuRegister st3 = { 3 };
const FpuRegister st4 = { 4 };
const FpuRegister st5 = { 5 };
const FpuRegister st6 = { 6 };
const FpuRegister st7 = { 7 };
const FloatRegister xmm0 = { 0 };
const FloatRegister xmm1 = { 1 };
const FloatRegister xmm2 = { 2 };
const FloatRegister xmm3 = { 3 };
const FloatRegister xmm4 = { 4 };
const FloatRegister xmm5 = { 5 };
const FloatRegister xmm6 = { 6 };
const FloatRegister xmm7 = { 7 };
static const uint8_t kModeDisp0 = 0;
static const uint8_t kModeDisp8 = 1;
static const uint8_t kModeDisp32 = 2;
static const uint8_t kModeReg = 3;
static const uint8_t kNoIndex = 4;
static const uint8_t kSIB = 4;
static const uint8_t kRIP = 5;
enum ConditionCode {
overflow,
no_overflow,
below,
not_below,
equal,
not_equal,
not_above,
above,
negative,
not_negative,
even_parity,
odd_parity,
less,
not_less,
not_greater,
greater,
zero = equal,
not_zero = not_equal,
less_equal = not_greater,
below_equal = not_above,
greater_equal = not_less,
above_equal = not_below,
parity = even_parity,
not_parity = odd_parity
};
enum Scale {
NoScale,
ScaleTwo,
ScaleFour,
ScaleEight,
ScalePointer = ScaleFour
};
struct Operand
{
friend class AssemblerX86;
public:
Operand(Register reg, int32_t disp) {
if (reg == esp) {
// If the reg is esp, we need a SIB encoding.
if (disp == 0)
sib_disp0(NoScale, kNoIndex, reg.code);
else if (disp >= SCHAR_MIN && disp <= SCHAR_MAX)
sib_disp8(NoScale, kNoIndex, reg.code, disp);
else
sib_disp32(NoScale, kNoIndex, reg.code, disp);
} else if (disp == 0 && reg != ebp) {
// note, [ebp+0] is disp32/rip
modrm_disp0(reg.code);
} else if (disp >= SCHAR_MIN && disp <= SCHAR_MAX) {
modrm_disp8(reg.code, disp);
} else {
modrm_disp32(reg.code, disp);
}
}
Operand(Register base, Scale scale, int32_t disp = 0) {
if (disp == 0 && base != ebp)
sib_disp0(scale, kNoIndex, base.code);
else if (disp >= SCHAR_MIN && disp <= SCHAR_MAX)
sib_disp8(scale, kNoIndex, base.code, disp);
else
sib_disp32(scale, kNoIndex, base.code, disp);
}
Operand(Register base, Register index, Scale scale, int32_t disp = 0) {
assert(index.code != kNoIndex);
if (disp == 0 && base != ebp)
sib_disp0(scale, index.code, base.code);
else if (disp >= SCHAR_MIN && disp <= SCHAR_MAX)
sib_disp8(scale, index.code, base.code, disp);
else
sib_disp32(scale, index.code, base.code, disp);
}
explicit Operand(ExternalAddress address) {
modrm(kModeDisp0, kRIP);
*reinterpret_cast<const void **>(bytes_ + 1) = address.address();
}
bool isRegister() const {
return mode() == kModeReg;
}
bool isRegister(Register r) const {
return mode() == kModeReg && rm() == r.code;
}
int registerCode() const {
return rm();
}
uint8_t getByte(size_t index) const {
assert(index < length());
return bytes_[index];
}
size_t length() const {
if (mode() == kModeDisp0 && rm() == kRIP)
return 5;
size_t sib = (mode() != kModeReg && rm() == kSIB);
if (mode() == kModeDisp32)
return 5 + sib;
if (mode() == kModeDisp8)
return 2 + sib;
return 1 + sib;
}
private:
explicit Operand(Register reg) {
modrm(kModeReg, reg.code);
}
void modrm(uint8_t mode, uint8_t rm) {
assert(mode <= 3);
assert(rm <= 7);
bytes_[0] = (mode << 6) | rm;
}
void modrm_disp0(uint8_t rm) {
modrm(kModeDisp0, rm);
}
void modrm_disp8(uint8_t rm, int8_t disp) {
modrm(kModeDisp8, rm);
bytes_[1] = disp;
}
void modrm_disp32(uint8_t rm, int32_t disp) {
modrm(kModeDisp32, rm);
*reinterpret_cast<int32_t *>(bytes_ + 1) = disp;
}
void sib(uint8_t mode, Scale scale, uint8_t index, uint8_t base) {
modrm(mode, kSIB);
assert(scale <= 3);
assert(index <= 7);
assert(base <= 7);
bytes_[1] = (uint8_t(scale) << 6) | (index << 3) | base;
}
void sib_disp0(Scale scale, uint8_t index, uint8_t base) {
sib(kModeDisp0, scale, index, base);
}
void sib_disp8(Scale scale, uint8_t index, uint8_t base, int8_t disp) {
sib(kModeDisp8, scale, index, base);
bytes_[2] = disp;
}
void sib_disp32(Scale scale, uint8_t index, uint8_t base, int32_t disp) {
sib(kModeDisp32, scale, index, base);
*reinterpret_cast<int32_t *>(bytes_ + 2) = disp;
}
private:
uint8_t rm() const {
return bytes_[0] & 7;
}
uint8_t mode() const {
return bytes_[0] >> 6;
}
private:
uint8_t bytes_[6];
};
class AssemblerX86 : public Assembler
{
private:
// List of processor features; to be used, this must be filled in at
// startup.
static CPUFeatures X86Features;
public:
static void SetFeatures(const CPUFeatures &features) {
X86Features = features;
}
static const CPUFeatures &Features() {
return X86Features;
}
void movl(Register dest, Register src) {
emit1(0x89, src.code, dest.code);
}
void movl(Register dest, const Operand &src) {
emit1(0x8b, dest.code, src);
}
void movl(const Operand &dest, Register src) {
emit1(0x89, src.code, dest);
}
void movl(Register dest, int32_t imm) {
emit1(0xb8 + dest.code);
writeInt32(imm);
}
void movl(const Operand &dest, int32_t imm) {
if (dest.isRegister())
emit1(0xb8 + dest.registerCode());
else
emit1(0xc7, 0, dest);
writeInt32(imm);
}
void movw(const Operand &dest, Register src) {
emit1(0x89, src.code, dest);
}
void movw(Register dest, const Operand &src) {
emit1(0x8b, dest.code, src);
}
void movb(const Operand &dest, Register src) {
emit1(0x88, src.code, dest);
}
void movb(Register dest, const Operand &src) {
emit1(0x8a, dest.code, src);
}
void movzxb(Register dest, const Operand &src) {
emit2(0x0f, 0xb6, dest.code, src);
}
void movzxb(Register dest, const Register src) {
emit2(0x0f, 0xb6, dest.code, src.code);
}
void movzxw(Register dest, const Operand &src) {
emit2(0x0f, 0xb7, dest.code, src);
}
void movzxw(Register dest, const Register src) {
emit2(0x0f, 0xb7, dest.code, src.code);
}
void lea(Register dest, const Operand &src) {
emit1(0x8d, dest.code, src);
}
void xchgl(Register dest, Register src) {
if (src == eax)
emit1(0x90 + dest.code);
else if (dest == eax)
emit1(0x90 + src.code);
else
emit1(0x87, src.code, dest.code);
}
void shll_cl(Register dest) {
shift_cl(dest.code, 4);
}
void shll(Register dest, uint8_t imm) {
shift_imm(dest.code, 4, imm);
}
void shll(const Operand &dest, uint8_t imm) {
shift_imm(dest, 4, imm);
}
void shrl_cl(Register dest) {
shift_cl(dest.code, 5);
}
void shrl(Register dest, uint8_t imm) {
shift_imm(dest.code, 5, imm);
}
void shrl(const Operand &dest, uint8_t imm) {
shift_imm(dest, 5, imm);
}
void sarl_cl(Register dest) {
shift_cl(dest.code, 7);
}
void sarl(Register dest, uint8_t imm) {
shift_imm(dest.code, 7, imm);
}
void sarl(const Operand &dest, uint8_t imm) {
shift_imm(dest, 7, imm);
}
void cmpl(Register left, int32_t imm) {
alu_imm(7, imm, Operand(left));
}
void cmpl(const Operand &left, int32_t imm) {
alu_imm(7, imm, left);
}
void cmpl(Register left, Register right) {
emit1(0x39, right.code, left.code);
}
void cmpl(const Operand &left, Register right) {
emit1(0x39, right.code, left);
}
void cmpl(Register left, const Operand &right) {
emit1(0x3b, left.code, right);
}
void andl(Register dest, int32_t imm) {
alu_imm(4, imm, Operand(dest));
}
void andl(const Operand &dest, int32_t imm) {
alu_imm(4, imm, dest);
}
void andl(Register dest, Register src) {
emit1(0x21, src.code, dest.code);
}
void andl(const Operand &dest, Register src) {
emit1(0x21, src.code, dest);
}
void andl(Register dest, const Operand &src) {
emit1(0x23, dest.code, src);
}
void orl(Register dest, Register src) {
emit1(0x09, src.code, dest.code);
}
void orl(const Operand &dest, Register src) {
emit1(0x09, src.code, dest);
}
void orl(Register dest, const Operand &src) {
emit1(0x0b, dest.code, src);
}
void xorl(Register dest, Register src) {
emit1(0x31, src.code, dest.code);
}
void xorl(const Operand &dest, Register src) {
emit1(0x31, src.code, dest);
}
void xorl(Register dest, const Operand &src) {
emit1(0x33, dest.code, src);
}
void subl(Register dest, Register src) {
emit1(0x29, src.code, dest.code);
}
void subl(const Operand &dest, Register src) {
emit1(0x29, src.code, dest);
}
void subl(Register dest, const Operand &src) {
emit1(0x2b, dest.code, src);
}
void subl(Register dest, int32_t imm) {
alu_imm(5, imm, Operand(dest));
}
void subl(const Operand &dest, int32_t imm) {
alu_imm(5, imm, dest);
}
void addl(Register dest, Register src) {
emit1(0x01, src.code, dest.code);
}
void addl(const Operand &dest, Register src) {
emit1(0x01, src.code, dest);
}
void addl(Register dest, const Operand &src) {
emit1(0x03, dest.code, src);
}
void addl(Register dest, int32_t imm) {
alu_imm(0, imm, Operand(dest));
}
void addl(const Operand &dest, int32_t imm) {
alu_imm(0, imm, dest);
}
void imull(Register dest, const Operand &src) {
emit2(0x0f, 0xaf, dest.code, src);
}
void imull(Register dest, Register src) {
emit2(0x0f, 0xaf, dest.code, src.code);
}
void imull(Register dest, const Operand &src, int32_t imm) {
if (imm >= SCHAR_MIN && imm <= SCHAR_MAX) {
emit1(0x6b, dest.code, src);
*pos_++ = imm;
} else {
emit1(0x69, dest.code, src);
writeInt32(imm);
}
}
void imull(Register dest, Register src, int32_t imm) {
imull(dest, Operand(src), imm);
}
void testl(const Operand &op1, Register op2) {
emit1(0x85, op2.code, op1);
}
void testl(Register op1, Register op2) {
emit1(0x85, op2.code, op1.code);
}
void set(ConditionCode cc, const Operand &dest) {
emit2(0x0f, 0x90 + uint8_t(cc), 0, dest);
}
void set(ConditionCode cc, Register dest) {
emit2(0x0f, 0x90 + uint8_t(cc), 0, dest.code);
}
void negl(Register srcdest) {
emit1(0xf7, 3, srcdest.code);
}
void negl(const Operand &srcdest) {
emit1(0xf7, 3, srcdest);
}
void notl(Register srcdest) {
emit1(0xf7, 2, srcdest.code);
}
void notl(const Operand &srcdest) {
emit1(0xf7, 2, srcdest);
}
void idivl(Register dividend) {
emit1(0xf7, 7, dividend.code);
}
void idivl(const Operand &dividend) {
emit1(0xf7, 7, dividend);
}
void ret() {
emit1(0xc3);
}
void cld() {
emit1(0xfc);
}
void push(Register reg) {
emit1(0x50 + reg.code);
}
void push(const Operand &src) {
if (src.isRegister())
emit1(0x50 + src.registerCode());
else
emit1(0xff, 6, src);
}
void push(int32_t imm) {
emit1(0x68);
writeInt32(imm);
}
void pop(Register reg) {
emit1(0x58 + reg.code);
}
void pop(const Operand &src) {
if (src.isRegister())
emit1(0x58 + src.registerCode());
else
emit1(0x8f, 0, src);
}
void rep_movsb() {
emit2(0xf3, 0xa4);
}
void rep_movsd() {
emit2(0xf3, 0xa5);
}
void rep_stosd() {
emit2(0xf3, 0xab);
}
void breakpoint() {
emit1(0xcc);
}
void fld32(const Operand &src) {
emit1(0xd9, 0, src);
}
void fild32(const Operand &src) {
emit1(0xdb, 0, src);
}
void fistp32(const Operand &dest) {
emit1(0xdb, 3, dest);
}
void fadd32(const Operand &src) {
emit1(0xd8, 0, src);
}
void fsub32(const Operand &src) {
emit1(0xd8, 4, src);
}
void fmul32(const Operand &src) {
emit1(0xd8, 1, src);
}
void fdiv32(const Operand &src) {
emit1(0xd8, 6, src);
}
void fstp32(const Operand &dest) {
emit1(0xd9, 3, dest);
}
void fstp(FpuRegister src) {
emit2(0xdd, 0xd8 + src.code);
}
void fldcw(const Operand &src) {
emit1(0xd9, 5, src);
}
void fstcw(const Operand &dest) {
emit2(0x9b, 0xd9, 7, dest);
}
void fsubr32(const Operand &src) {
emit1(0xd8, 5, src);
}
void fldz() {
emit2(0xd9, 0xee);
}
// Compare st0 with stN.
void fucomip(FpuRegister other) {
emit2(0xdf, 0xe8 + other.code);
}
// At least one argument of these forms must be st0.
void fadd32(FpuRegister dest, FpuRegister src) {
assert(dest == st0 || src == st0);
if (dest == st0)
emit2(0xd8, 0xc0 + dest.code);
else
emit2(0xdc, 0xc0 + src.code);
}
void jmp32(Label *dest) {
emit1(0xe9);
emitJumpTarget(dest);
}
void jmp(Label *dest) {
int8_t d8;
if (canEmitSmallJump(dest, &d8)) {
emit2(0xeb, d8);
} else {
emit1(0xe9);
emitJumpTarget(dest);
}
}
void jmp(Register target) {
emit1(0xff, 4, target.code);
}
void jmp(const Operand &target) {
emit1(0xff, 4, target);
}
void j32(ConditionCode cc, Label *dest) {
emit2(0x0f, 0x80 + uint8_t(cc));
emitJumpTarget(dest);
}
void j(ConditionCode cc, Label *dest) {
int8_t d8;
if (canEmitSmallJump(dest, &d8)) {
emit2(0x70 + uint8_t(cc), d8);
} else {
emit2(0x0f, 0x80 + uint8_t(cc));
emitJumpTarget(dest);
}
}
void call(Label *dest) {
emit1(0xe8);
emitJumpTarget(dest);
}
void bind(Label *target) {
if (outOfMemory()) {
// If we ran out of memory, the code stream is potentially invalid and
// we cannot use the embedded linked list.
target->bind(pc());
return;
}
assert(!target->bound());
uint32_t status = target->status();
while (Label::More(status)) {
// Grab the offset. It should be at least a 1byte op + rel32.
uint32_t offset = Label::ToOffset(status);
assert(offset >= 5);
// Grab the delta from target to pc.
ptrdiff_t delta = pos_ - (buffer() + offset);
assert(delta >= INT_MIN && delta <= INT_MAX);
int32_t *p = reinterpret_cast<int32_t *>(buffer() + offset - 4);
status = *p;
*p = delta;
}
target->bind(pc());
}
void bind(DataLabel *address) {
if (outOfMemory())
return;
if (address->used()) {
uint32_t offset = DataLabel::ToOffset(address->status());
*reinterpret_cast<int32_t *>(buffer() + offset - 4) = position() - int32_t(offset);
}
address->bind(pc());
}
void movl(Register dest, DataLabel *src) {
emit1(0xb8 + dest.code);
if (src->bound()) {
writeInt32(int32_t(src->offset()) - (position() + 4));
} else {
writeInt32(0xabcdef0);
src->use(pc());
}
if (!local_refs_.append(pc()))
outOfMemory_ = true;
}
void emit_absolute_address(Label *address) {
if (address->bound())
writeUint32(int32_t(address->offset()) - (position() + 4));
else
writeUint32(address->addPending(position() + 4));
if (!local_refs_.append(pc()))
outOfMemory_ = true;
}
void call(Register target) {
emit1(0xff, 2, target.code);
}
void call(const Operand &target) {
emit1(0xff, 2, target);
}
void call(ExternalAddress address) {
emit1(0xe8);
writeInt32(address.value());
if (!external_refs_.append(pc()))
outOfMemory_ = true;
}
void jmp(ExternalAddress address) {
assert(sizeof(address) == sizeof(int32_t));
emit1(0xe9);
writeInt32(address.value());
if (!external_refs_.append(pc()))
outOfMemory_ = true;
}
void cpuid() {
emit2(0x0f, 0xa2);
}
// SSE operations can only be used if the feature detection function has
// been run *and* detected the appropriate level of functionality.
void movss(FloatRegister dest, const Operand &src) {
assert(Features().sse);
emit3(0xf3, 0x0f, 0x10, dest.code, src);
}
void cvttss2si(Register dest, Register src) {
assert(Features().sse);
emit3(0xf3, 0x0f, 0x2c, dest.code, src.code);
}
void cvttss2si(Register dest, const Operand &src) {
assert(Features().sse);
emit3(0xf3, 0x0f, 0x2c, dest.code, src);
}
void cvtss2si(Register dest, Register src) {
assert(Features().sse);
emit3(0xf3, 0x0f, 0x2d, dest.code, src.code);
}
void cvtss2si(Register dest, const Operand &src) {
assert(Features().sse);
emit3(0xf3, 0x0f, 0x2d, dest.code, src);
}
void cvtsi2ss(FloatRegister dest, Register src) {
assert(Features().sse);
emit3(0xf3, 0x0f, 0x2a, dest.code, src.code);
}
void cvtsi2ss(FloatRegister dest, const Operand &src) {
assert(Features().sse);
emit3(0xf3, 0x0f, 0x2a, dest.code, src);
}
void addss(FloatRegister dest, const Operand &src) {
assert(Features().sse);
emit3(0xf3, 0x0f, 0x58, dest.code, src);
}
void subss(FloatRegister dest, const Operand &src) {
assert(Features().sse);
emit3(0xf3, 0x0f, 0x5c, dest.code, src);
}
void mulss(FloatRegister dest, const Operand &src) {
assert(Features().sse);
emit3(0xf3, 0x0f, 0x59, dest.code, src);
}
void divss(FloatRegister dest, const Operand &src) {
assert(Features().sse);
emit3(0xf3, 0x0f, 0x5e, dest.code, src);
}
void xorps(FloatRegister dest, FloatRegister src) {
assert(Features().sse);
emit2(0x0f, 0x57, src.code, dest.code);
}
void ucomiss(FloatRegister left, FloatRegister right) {
emit2(0x0f, 0x2e, right.code, left.code);
}
void ucomiss(const Operand &left, FloatRegister right) {
emit2(0x0f, 0x2e, right.code, left);
}
// SSE2-only instructions.
void movd(Register dest, FloatRegister src) {
assert(Features().sse2);
emit3(0x66, 0x0f, 0x7e, dest.code, src.code);
}
void movd(Register dest, const Operand &src) {
assert(Features().sse2);
emit3(0x66, 0x0f, 0x7e, dest.code, src);
}
static void PatchRel32Absolute(uint8_t *ip, void *ptr) {
int32_t delta = uint32_t(ptr) - uint32_t(ip);
*reinterpret_cast<int32_t *>(ip - 4) = delta;
}
void emitToExecutableMemory(void *code) {
assert(!outOfMemory());
// Relocate anything we emitted as rel32 with an external pointer.
uint8_t *base = reinterpret_cast<uint8_t *>(code);
memcpy(base, buffer(), length());
for (size_t i = 0; i < external_refs_.length(); i++) {
size_t offset = external_refs_[i];
PatchRel32Absolute(base + offset, *reinterpret_cast<void **>(base + offset - 4));
}
// Relocate everything we emitted as an abs32 with an internal offset. Note
// that in the code stream, we use relative offsets so we can use both Label
// and DataLabel.
for (size_t i = 0; i < local_refs_.length(); i++) {
size_t offset = local_refs_[i];
int32_t delta = *reinterpret_cast<int32_t *>(base + offset - 4);
*reinterpret_cast<void **>(base + offset - 4) = base + offset + delta;
}
}
void align(uint32_t bytes) {
int32_t delta = (pc() & ~(bytes - 1)) + bytes - pc();
for (int32_t i = 0; i < delta; i++)
emit1(0xcc);
}
private:
bool canEmitSmallJump(Label *dest, int8_t *deltap) {
if (!dest->bound())
return false;
// All small jumps are assumed to be 2 bytes.
ptrdiff_t delta = ptrdiff_t(dest->offset()) - (position() + 2);
if (delta < SCHAR_MIN || delta > SCHAR_MAX)
return false;
*deltap = delta;
return true;
}
void emitJumpTarget(Label *dest) {
if (dest->bound()) {
ptrdiff_t delta = ptrdiff_t(dest->offset()) - (position() + 4);
assert(delta >= INT_MIN && delta <= INT_MAX);
writeInt32(delta);
} else {
writeUint32(dest->addPending(position() + 4));
}
}
void emit(uint8_t reg, const Operand &operand) {
*pos_++ = operand.getByte(0) | (reg << 3);
size_t length = operand.length();
for (size_t i = 1; i < length; i++)
*pos_++ = operand.getByte(i);
}
void emit1(uint8_t opcode) {
ensureSpace();
*pos_++ = opcode;
}
void emit1(uint8_t opcode, uint8_t reg, uint8_t opreg) {
ensureSpace();
assert(reg <= 7);
assert(opreg <= 7);
*pos_++ = opcode;
*pos_++ = (kModeReg << 6) | (reg << 3) | opreg;
}
void emit1(uint8_t opcode, uint8_t reg, const Operand &operand) {
ensureSpace();
assert(reg <= 7);
*pos_++ = opcode;
emit(reg, operand);
}
void emit2(uint8_t prefix, uint8_t opcode) {
ensureSpace();
*pos_++ = prefix;
*pos_++ = opcode;
}
void emit2(uint8_t prefix, uint8_t opcode, uint8_t reg, uint8_t opreg) {
emit2(prefix, opcode);
assert(reg <= 7);
*pos_++ = (kModeReg << 6) | (reg << 3) | opreg;
}
void emit2(uint8_t prefix, uint8_t opcode, uint8_t reg, const Operand &operand) {
emit2(prefix, opcode);
emit(reg, operand);
}
void emit3(uint8_t prefix1, uint8_t prefix2, uint8_t opcode) {
ensureSpace();
*pos_++ = prefix1;
*pos_++ = prefix2;
*pos_++ = opcode;
}
void emit3(uint8_t prefix1, uint8_t prefix2, uint8_t opcode, uint8_t reg, uint8_t opreg) {
emit3(prefix1, prefix2, opcode);
assert(reg <= 7);
*pos_++ = (kModeReg << 6) | (reg << 3) | opreg;
}
void emit3(uint8_t prefix1, uint8_t prefix2, uint8_t opcode, uint8_t reg, const Operand &operand) {
emit3(prefix1, prefix2, opcode);
emit(reg, operand);
}
template <typename T>
void shift_cl(const T &t, uint8_t r) {
emit1(0xd3, r, t);
}
template <typename T>
void shift_imm(const T &t, uint8_t r, int32_t imm) {
if (imm == 1) {
emit1(0xd1, r, t);
} else {
emit1(0xc1, r, t);
*pos_++ = imm & 0x1F;
}
}
void alu_imm(uint8_t r, int32_t imm, const Operand &operand) {
if (imm >= SCHAR_MIN && imm <= SCHAR_MAX) {
emit1(0x83, r, operand);
*pos_++ = uint8_t(imm & 0xff);
} else if (operand.isRegister(eax)) {
emit1(0x05 | (r << 3));
writeInt32(imm);
} else {
emit1(0x81, r, operand);
writeInt32(imm);
}
}
private:
ke::Vector<uint32_t> external_refs_;
ke::Vector<uint32_t> local_refs_;
};
#endif // _include_sourcepawn_assembler_x86_h__