/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "disassembler_mips.h"
#include <iostream>
#include "base/logging.h"
#include "base/stringprintf.h"
#include "thread.h"
namespace art {
namespace mips {
struct MipsInstruction {
uint32_t mask;
uint32_t value;
const char* name;
const char* args_fmt;
bool Matches(uint32_t instruction) const {
return (instruction & mask) == value;
}
};
static const uint32_t kOpcodeShift = 26;
static const uint32_t kCop1 = (17 << kOpcodeShift);
static const uint32_t kITypeMask = (0x3f << kOpcodeShift);
static const uint32_t kJTypeMask = (0x3f << kOpcodeShift);
static const uint32_t kRTypeMask = ((0x3f << kOpcodeShift) | (0x3f));
static const uint32_t kSpecial2Mask = (0x3f << kOpcodeShift);
static const uint32_t kFpMask = kRTypeMask;
static const MipsInstruction gMipsInstructions[] = {
// "sll r0, r0, 0" is the canonical "nop", used in delay slots.
{ 0xffffffff, 0, "nop", "" },
// R-type instructions.
{ kRTypeMask, 0, "sll", "DTA", },
// 0, 1, movci
{ kRTypeMask, 2, "srl", "DTA", },
{ kRTypeMask, 3, "sra", "DTA", },
{ kRTypeMask, 4, "sllv", "DTS", },
{ kRTypeMask, 6, "srlv", "DTS", },
{ kRTypeMask, 7, "srav", "DTS", },
{ kRTypeMask, 8, "jr", "S", },
{ kRTypeMask | (0x1f << 11), 9 | (31 << 11), "jalr", "S", }, // rd = 31 is implicit.
{ kRTypeMask, 9, "jalr", "DS", }, // General case.
{ kRTypeMask | (0x1f << 6), 10, "movz", "DST", },
{ kRTypeMask | (0x1f << 6), 11, "movn", "DST", },
{ kRTypeMask, 12, "syscall", "", }, // TODO: code
{ kRTypeMask, 13, "break", "", }, // TODO: code
{ kRTypeMask, 15, "sync", "", }, // TODO: type
{ kRTypeMask, 16, "mfhi", "D", },
{ kRTypeMask, 17, "mthi", "S", },
{ kRTypeMask, 18, "mflo", "D", },
{ kRTypeMask, 19, "mtlo", "S", },
{ kRTypeMask, 24, "mult", "ST", },
{ kRTypeMask, 25, "multu", "ST", },
{ kRTypeMask, 26, "div", "ST", },
{ kRTypeMask, 27, "divu", "ST", },
{ kRTypeMask, 32, "add", "DST", },
{ kRTypeMask, 33, "addu", "DST", },
{ kRTypeMask, 34, "sub", "DST", },
{ kRTypeMask, 35, "subu", "DST", },
{ kRTypeMask, 36, "and", "DST", },
{ kRTypeMask, 37, "or", "DST", },
{ kRTypeMask, 38, "xor", "DST", },
{ kRTypeMask, 39, "nor", "DST", },
{ kRTypeMask, 42, "slt", "DST", },
{ kRTypeMask, 43, "sltu", "DST", },
// 0, 48, tge
// 0, 49, tgeu
// 0, 50, tlt
// 0, 51, tltu
// 0, 52, teq
// 0, 54, tne
// SPECIAL2
{ kSpecial2Mask | 0x7ff, (28 << kOpcodeShift) | 2, "mul", "DST" },
{ kSpecial2Mask | 0x7ff, (28 << kOpcodeShift) | 32, "clz", "DS" },
{ kSpecial2Mask | 0xffff, (28 << kOpcodeShift) | 0, "madd", "ST" },
{ kSpecial2Mask | 0xffff, (28 << kOpcodeShift) | 1, "maddu", "ST" },
{ kSpecial2Mask | 0xffff, (28 << kOpcodeShift) | 2, "mul", "DST" },
{ kSpecial2Mask | 0xffff, (28 << kOpcodeShift) | 4, "msub", "ST" },
{ kSpecial2Mask | 0xffff, (28 << kOpcodeShift) | 5, "msubu", "ST" },
{ kSpecial2Mask | 0x3f, (28 << kOpcodeShift) | 0x3f, "sdbbp", "" }, // TODO: code
// J-type instructions.
{ kJTypeMask, 2 << kOpcodeShift, "j", "L" },
{ kJTypeMask, 3 << kOpcodeShift, "jal", "L" },
// I-type instructions.
{ kITypeMask, 4 << kOpcodeShift, "beq", "STB" },
{ kITypeMask, 5 << kOpcodeShift, "bne", "STB" },
{ kITypeMask | (0x1f << 16), 1 << kOpcodeShift | (1 << 16), "bgez", "SB" },
{ kITypeMask | (0x1f << 16), 1 << kOpcodeShift | (0 << 16), "bltz", "SB" },
{ kITypeMask | (0x1f << 16), 1 << kOpcodeShift | (2 << 16), "bltzl", "SB" },
{ kITypeMask | (0x1f << 16), 1 << kOpcodeShift | (16 << 16), "bltzal", "SB" },
{ kITypeMask | (0x1f << 16), 1 << kOpcodeShift | (18 << 16), "bltzall", "SB" },
{ kITypeMask | (0x1f << 16), 6 << kOpcodeShift | (0 << 16), "blez", "SB" },
{ kITypeMask | (0x1f << 16), 7 << kOpcodeShift | (0 << 16), "bgtz", "SB" },
{ 0xffff0000, (4 << kOpcodeShift), "b", "B" },
{ 0xffff0000, (1 << kOpcodeShift) | (17 << 16), "bal", "B" },
{ kITypeMask, 8 << kOpcodeShift, "addi", "TSi", },
{ kITypeMask, 9 << kOpcodeShift, "addiu", "TSi", },
{ kITypeMask, 10 << kOpcodeShift, "slti", "TSi", },
{ kITypeMask, 11 << kOpcodeShift, "sltiu", "TSi", },
{ kITypeMask, 12 << kOpcodeShift, "andi", "TSi", },
{ kITypeMask, 13 << kOpcodeShift, "ori", "TSi", },
{ kITypeMask, 14 << kOpcodeShift, "ori", "TSi", },
{ kITypeMask, 15 << kOpcodeShift, "lui", "TI", },
{ kITypeMask, 32u << kOpcodeShift, "lb", "TO", },
{ kITypeMask, 33u << kOpcodeShift, "lh", "TO", },
{ kITypeMask, 35u << kOpcodeShift, "lw", "TO", },
{ kITypeMask, 36u << kOpcodeShift, "lbu", "TO", },
{ kITypeMask, 37u << kOpcodeShift, "lhu", "TO", },
{ kITypeMask, 40u << kOpcodeShift, "sb", "TO", },
{ kITypeMask, 41u << kOpcodeShift, "sh", "TO", },
{ kITypeMask, 43u << kOpcodeShift, "sw", "TO", },
{ kITypeMask, 49u << kOpcodeShift, "lwc1", "tO", },
{ kITypeMask, 57u << kOpcodeShift, "swc1", "tO", },
// Floating point.
{ kFpMask, kCop1 | 0, "add", "fdst" },
{ kFpMask, kCop1 | 1, "sub", "fdst" },
{ kFpMask, kCop1 | 2, "mul", "fdst" },
{ kFpMask, kCop1 | 3, "div", "fdst" },
{ kFpMask | (0x1f << 16), kCop1 | 4, "sqrt", "fdst" },
{ kFpMask | (0x1f << 16), kCop1 | 5, "abs", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 6, "mov", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 7, "neg", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 8, "round.l", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 9, "trunc.l", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 10, "ceil.l", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 11, "floor.l", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 12, "round.w", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 13, "trunc.w", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 14, "ceil.w", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 15, "floor.w", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 32, "cvt.s", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 33, "cvt.d", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 36, "cvt.w", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 37, "cvt.l", "fds" },
{ kFpMask | (0x1f << 16), kCop1 | 38, "cvt.ps", "fds" },
};
static uint32_t ReadU32(const uint8_t* ptr) {
// We only support little-endian MIPS.
return ptr[0] | (ptr[1] << 8) | (ptr[2] << 16) | (ptr[3] << 24);
}
static void DumpMips(std::ostream& os, const uint8_t* instr_ptr) {
uint32_t instruction = ReadU32(instr_ptr);
uint32_t rs = (instruction >> 21) & 0x1f; // I-type, R-type.
uint32_t rt = (instruction >> 16) & 0x1f; // I-type, R-type.
uint32_t rd = (instruction >> 11) & 0x1f; // R-type.
uint32_t sa = (instruction >> 6) & 0x1f; // R-type.
std::string opcode;
std::ostringstream args;
// TODO: remove this!
uint32_t op = (instruction >> 26) & 0x3f;
uint32_t function = (instruction & 0x3f); // R-type.
opcode = StringPrintf("op=%d fn=%d", op, function);
for (size_t i = 0; i < arraysize(gMipsInstructions); ++i) {
if (gMipsInstructions[i].Matches(instruction)) {
opcode = gMipsInstructions[i].name;
for (const char* args_fmt = gMipsInstructions[i].args_fmt; *args_fmt; ++args_fmt) {
switch (*args_fmt) {
case 'A': // sa (shift amount).
args << sa;
break;
case 'B': // Branch offset.
{
int32_t offset = static_cast<int16_t>(instruction & 0xffff);
offset <<= 2;
offset += 4; // Delay slot.
args << StringPrintf("%p ; %+d", instr_ptr + offset, offset);
}
break;
case 'D': args << 'r' << rd; break;
case 'd': args << 'f' << rd; break;
case 'f': // Floating point "fmt".
{
size_t fmt = (instruction >> 21) & 0x7; // TODO: other fmts?
switch (fmt) {
case 0: opcode += ".s"; break;
case 1: opcode += ".d"; break;
case 4: opcode += ".w"; break;
case 5: opcode += ".l"; break;
case 6: opcode += ".ps"; break;
default: opcode += ".?"; break;
}
continue; // No ", ".
}
break;
case 'I': // Upper 16-bit immediate.
args << reinterpret_cast<void*>((instruction & 0xffff) << 16);
break;
case 'i': // Sign-extended lower 16-bit immediate.
args << static_cast<int16_t>(instruction & 0xffff);
break;
case 'L': // Jump label.
{
// TODO: is this right?
uint32_t instr_index = (instruction & 0x1ffffff);
uint32_t target = (instr_index << 2);
target |= (reinterpret_cast<uintptr_t>(instr_ptr + 4) & 0xf0000000);
args << reinterpret_cast<void*>(target);
}
break;
case 'O': // +x(rs)
{
int32_t offset = static_cast<int16_t>(instruction & 0xffff);
args << StringPrintf("%+d(r%d)", offset, rs);
if (rs == 17) {
args << " ; ";
Thread::DumpThreadOffset(args, offset, 4);
}
}
break;
case 'S': args << 'r' << rs; break;
case 's': args << 'f' << rs; break;
case 'T': args << 'r' << rt; break;
case 't': args << 'f' << rt; break;
}
if (*(args_fmt + 1)) {
args << ", ";
}
}
break;
}
}
os << StringPrintf("%p: %08x\t%-7s ", instr_ptr, instruction, opcode.c_str()) << args.str() << '\n';
}
DisassemblerMips::DisassemblerMips() {
}
size_t DisassemblerMips::Dump(std::ostream& os, const uint8_t* begin) {
DumpMips(os, begin);
return 4;
}
void DisassemblerMips::Dump(std::ostream& os, const uint8_t* begin, const uint8_t* end) {
for (const uint8_t* cur = begin; cur < end; cur += 4) {
DumpMips(os, cur);
}
}
} // namespace mips
} // namespace art