75 lines
3.5 KiB
C
75 lines
3.5 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/macros.h"
|
|
#include "libc/str/str.h"
|
|
#include "third_party/xed/x86.h"
|
|
#include "tool/build/lib/machine.h"
|
|
#include "tool/build/lib/memory.h"
|
|
#include "tool/build/lib/stats.h"
|
|
#include "tool/build/lib/throw.h"
|
|
|
|
static bool IsOpcodeEqual(uint8_t *a, uint8_t b[16], size_t size) {
|
|
if (likely(size)) {
|
|
return memcmp(a, b, size) == 0;
|
|
} else {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
void LoadInstruction(struct Machine *m) {
|
|
unsigned i;
|
|
enum XedError err;
|
|
uint8_t *addr, *toil, copy[15];
|
|
if ((i = 0x1000 - (m->ip & 0xfff)) >= 15) {
|
|
if (ROUNDDOWN(m->ip, 0x1000) == m->codevirt && m->ip) {
|
|
addr = m->codereal + (m->ip & 0xfff);
|
|
} else {
|
|
m->codevirt = ROUNDDOWN(m->ip, 0x1000);
|
|
m->codereal = ResolveAddress(m, m->codevirt);
|
|
addr = m->codereal + (m->ip & 0xfff);
|
|
}
|
|
m->xedd = m->icache + (m->ip & (ARRAYLEN(m->icache) - 1));
|
|
if (IsOpcodeEqual(addr, m->xedd->bytes, m->xedd->length)) {
|
|
taken++;
|
|
} else {
|
|
ntaken++;
|
|
xed_decoded_inst_zero_set_mode(m->xedd, XED_MACHINE_MODE_LONG_64);
|
|
if (xed_instruction_length_decode(m->xedd, addr, 15)) {
|
|
HaltMachine(m, kMachineDecodeError);
|
|
}
|
|
}
|
|
} else {
|
|
m->xedd = m->icache;
|
|
xed_decoded_inst_zero_set_mode(m->xedd, XED_MACHINE_MODE_LONG_64);
|
|
addr = ResolveAddress(m, m->ip);
|
|
if ((toil = FindReal(m, m->ip + i))) {
|
|
memcpy(copy, addr, i);
|
|
memcpy(copy + i, toil, 15 - i);
|
|
if ((err = xed_instruction_length_decode(m->xedd, copy, 15))) {
|
|
HaltMachine(m, kMachineDecodeError);
|
|
}
|
|
} else {
|
|
if ((err = xed_instruction_length_decode(m->xedd, addr, i))) {
|
|
HaltMachine(m, kMachineDecodeError);
|
|
}
|
|
}
|
|
}
|
|
}
|