cosmopolitan/tool/build/lib/modrm.c

249 lines
8.3 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ This program is free software; you can redistribute it and/or modify │
│ it under the terms of the GNU General Public License as published by │
│ the Free Software Foundation; version 2 of the License. │
│ │
│ 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, write to the Free Software │
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
│ 02110-1301 USA │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/log/check.h"
#include "tool/build/lib/endian.h"
#include "tool/build/lib/machine.h"
#include "tool/build/lib/memory.h"
#include "tool/build/lib/modrm.h"
/**
* Computes virtual address based on modrm and sib bytes.
*/
int64_t ComputeAddress(const struct Machine *m, uint32_t rde) {
uint64_t i;
DCHECK(m->xedd->op.has_modrm);
DCHECK(!IsModrmRegister(rde));
i = m->xedd->op.disp;
if (!SibExists(rde)) {
if (IsRipRelative(rde)) {
i += m->ip;
} else {
i += Read64(RegRexbRm(m, rde));
}
} else {
DCHECK(m->xedd->op.has_sib);
if (SibHasBase(rde)) {
i += Read64(RegRexbBase(m, rde));
}
if (SibHasIndex(rde)) {
i += Read64(RegRexxIndex(m, rde)) << m->xedd->op.scale;
}
}
i += GetSegment(m);
if (Asz(rde)) i &= 0xffffffff;
return i;
}
void *ComputeReserveAddressRead(struct Machine *m, uint32_t rde, size_t n) {
int64_t v;
v = ComputeAddress(m, rde);
SetReadAddr(m, v, n);
return ReserveAddress(m, v, n);
}
void *ComputeReserveAddressRead1(struct Machine *m, uint32_t rde) {
return ComputeReserveAddressRead(m, rde, 1);
}
void *ComputeReserveAddressRead8(struct Machine *m, uint32_t rde) {
return ComputeReserveAddressRead(m, rde, 8);
}
void *ComputeReserveAddressWrite(struct Machine *m, uint32_t rde, size_t n) {
int64_t v;
v = ComputeAddress(m, rde);
SetWriteAddr(m, v, n);
return ReserveAddress(m, v, n);
}
void *ComputeReserveAddressWrite1(struct Machine *m, uint32_t rde) {
return ComputeReserveAddressWrite(m, rde, 1);
}
void *ComputeReserveAddressWrite4(struct Machine *m, uint32_t rde) {
return ComputeReserveAddressWrite(m, rde, 4);
}
void *ComputeReserveAddressWrite8(struct Machine *m, uint32_t rde) {
return ComputeReserveAddressWrite(m, rde, 8);
}
uint8_t *GetModrmRegisterMmPointerRead(struct Machine *m, uint32_t rde,
size_t n) {
if (IsModrmRegister(rde)) {
return MmRm(m, rde);
} else {
return ComputeReserveAddressRead(m, rde, n);
}
}
uint8_t *GetModrmRegisterMmPointerRead8(struct Machine *m, uint32_t rde) {
return GetModrmRegisterMmPointerRead(m, rde, 8);
}
uint8_t *GetModrmRegisterMmPointerWrite(struct Machine *m, uint32_t rde,
size_t n) {
if (IsModrmRegister(rde)) {
return MmRm(m, rde);
} else {
return ComputeReserveAddressWrite(m, rde, n);
}
}
uint8_t *GetModrmRegisterMmPointerWrite8(struct Machine *m, uint32_t rde) {
return GetModrmRegisterMmPointerWrite(m, rde, 8);
}
uint8_t *GetModrmRegisterBytePointerRead(struct Machine *m, uint32_t rde) {
int64_t v;
if (IsModrmRegister(rde)) {
return ByteRexbRm(m, rde);
} else {
return ComputeReserveAddressRead1(m, rde);
}
}
uint8_t *GetModrmRegisterBytePointerWrite(struct Machine *m, uint32_t rde) {
int64_t v;
if (IsModrmRegister(rde)) {
return ByteRexbRm(m, rde);
} else {
return ComputeReserveAddressWrite1(m, rde);
}
}
uint8_t *GetModrmRegisterWordPointerRead(struct Machine *m, uint32_t rde,
size_t n) {
if (IsModrmRegister(rde)) {
return RegRexbRm(m, rde);
} else {
return ComputeReserveAddressRead(m, rde, n);
}
}
uint8_t *GetModrmRegisterWordPointerRead2(struct Machine *m, uint32_t rde) {
return GetModrmRegisterWordPointerRead(m, rde, 2);
}
uint8_t *GetModrmRegisterWordPointerRead4(struct Machine *m, uint32_t rde) {
return GetModrmRegisterWordPointerRead(m, rde, 4);
}
uint8_t *GetModrmRegisterWordPointerRead8(struct Machine *m, uint32_t rde) {
return GetModrmRegisterWordPointerRead(m, rde, 8);
}
uint8_t *GetModrmRegisterWordPointerReadOsz(struct Machine *m, uint32_t rde) {
if (!Osz(rde)) {
return GetModrmRegisterWordPointerRead8(m, rde);
} else {
return GetModrmRegisterWordPointerRead2(m, rde);
}
}
uint8_t *GetModrmRegisterWordPointerReadOszRexw(struct Machine *m,
uint32_t rde) {
if (Rexw(rde)) {
return GetModrmRegisterWordPointerRead8(m, rde);
} else if (!Osz(rde)) {
return GetModrmRegisterWordPointerRead4(m, rde);
} else {
return GetModrmRegisterWordPointerRead2(m, rde);
}
}
uint8_t *GetModrmRegisterWordPointerWrite(struct Machine *m, uint32_t rde,
size_t n) {
if (IsModrmRegister(rde)) {
return RegRexbRm(m, rde);
} else {
return ComputeReserveAddressWrite(m, rde, n);
}
}
uint8_t *GetModrmRegisterWordPointerWrite4(struct Machine *m, uint32_t rde) {
return GetModrmRegisterWordPointerWrite(m, rde, 4);
}
uint8_t *GetModrmRegisterWordPointerWrite8(struct Machine *m, uint32_t rde) {
return GetModrmRegisterWordPointerWrite(m, rde, 8);
}
uint8_t *GetModrmRegisterWordPointerWriteOszRexw(struct Machine *m,
uint32_t rde) {
if (Rexw(rde)) {
return GetModrmRegisterWordPointerWrite(m, rde, 8);
} else if (!Osz(rde)) {
return GetModrmRegisterWordPointerWrite(m, rde, 4);
} else {
return GetModrmRegisterWordPointerWrite(m, rde, 2);
}
}
uint8_t *GetModrmRegisterWordPointerWriteOsz(struct Machine *m, uint32_t rde) {
if (!Osz(rde)) {
return GetModrmRegisterWordPointerWrite(m, rde, 8);
} else {
return GetModrmRegisterWordPointerWrite(m, rde, 2);
}
}
uint8_t *GetModrmRegisterXmmPointerRead(struct Machine *m, uint32_t rde,
size_t n) {
if (IsModrmRegister(rde)) {
return XmmRexbRm(m, rde);
} else {
return ComputeReserveAddressRead(m, rde, n);
}
}
uint8_t *GetModrmRegisterXmmPointerRead4(struct Machine *m, uint32_t rde) {
return GetModrmRegisterXmmPointerRead(m, rde, 4);
}
uint8_t *GetModrmRegisterXmmPointerRead8(struct Machine *m, uint32_t rde) {
return GetModrmRegisterXmmPointerRead(m, rde, 8);
}
uint8_t *GetModrmRegisterXmmPointerRead16(struct Machine *m, uint32_t rde) {
return GetModrmRegisterXmmPointerRead(m, rde, 16);
}
uint8_t *GetModrmRegisterXmmPointerWrite(struct Machine *m, uint32_t rde,
size_t n) {
if (IsModrmRegister(rde)) {
return XmmRexbRm(m, rde);
} else {
return ComputeReserveAddressWrite(m, rde, n);
}
}
uint8_t *GetModrmRegisterXmmPointerWrite4(struct Machine *m, uint32_t rde) {
return GetModrmRegisterXmmPointerWrite(m, rde, 4);
}
uint8_t *GetModrmRegisterXmmPointerWrite8(struct Machine *m, uint32_t rde) {
return GetModrmRegisterXmmPointerWrite(m, rde, 8);
}
uint8_t *GetModrmRegisterXmmPointerWrite16(struct Machine *m, uint32_t rde) {
return GetModrmRegisterXmmPointerWrite(m, rde, 16);
}