Files
ppsspp/Core/MIPS/MIPSDis.cpp
T
Henrik RydgårdandClaude Opus 5.5 6d122f416e Keep JIT block entries and replacement hooks out of PSP memory
The JITs used to find a block by overwriting its first instruction with an "emuhack" holding
the offset into the code space, and replacement functions installed their own emuhack the same
way. Anything that read code (savestates, the debugger, memory dumps, cheats, the function
hasher, games reading their own code) had to translate them back.

Blocks now live in a block shadow: one u32 per guest instruction, indexed by the PC masked with
BLOCK_SHADOW_MASK (1GB on 64-bit, folding the kernel and uncached mirrors; 256MB on 32-bit, iOS
and Switch, where address space is short), with the low bits cleared so a misaligned PC can't
read across two entries. Only the ranges under memory views are committed, so a bad PC still
faults in the dispatcher, and the shadow is reserved before the memory map so it can't land in
a gap of the 4GB window. Entries hold full 32-bit offsets, lifting the 16MB limit. The
dispatchers on every backend, and the IR interpreter's loop, look blocks up there.

A hooked instruction without a compiled block gets the JIT's hook value in its entry: the offset
of the dispatcher's compile path (1 for the interpreters, the IR arena keeping that offset
empty), so dispatching there compiles a block, and the frontends substitute the hook. Compiling
replaces the entry with the block's, and destroying the block puts the hook value back. The hook
value is rewritten when the JIT changes or regenerates its dispatcher.

Hooks live in a map keyed by the masked address, and are dropped when the game overwrites the
hooked instruction, or when an icache invalidation finds the function's hash (immediates masked,
as when matching it) changed. Those checks run when queued invalidations are processed, since
cheats and the debugger queue them before writing. Installing and removing hooks invalidates
deferred, as it happens in HLE calls that can run inside a block. The cache instruction goes
through MIPSState, so it drops changed hooks too.

With clean memory, the save/clear/restore around savestates, memory reads and dumps goes away,
as do the source-range invalidations in the memcpy replacements, sceDmac and the cheats.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
2026-10-11 10:33:30 +02:00

358 lines
11 KiB
C++

// Copyright (c) 2012- PPSSPP Project.
// 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 2.0 or later versions.
// 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 2.0 for more details.
// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/
// Official git repository and contact information can be found at
// https://github.com/hrydgard/ppsspp and http://www.ppsspp.org/.
#include "Common/StringUtils.h"
#include "Core/HLE/HLE.h"
#include "Core/MemMap.h"
#include "Core/MIPS/MIPS.h"
#include "Core/MIPS/MIPSCodeUtils.h"
#include "Core/MIPS/MIPSDis.h"
#include "Core/MIPS/MIPSTables.h"
#include "Core/MIPS/MIPSDebugInterface.h"
#define _RS ((op>>21) & 0x1F)
#define _RT ((op>>16) & 0x1F)
#define _RD ((op>>11) & 0x1F)
#define _FS ((op>>11) & 0x1F)
#define _FT ((op>>16) & 0x1F)
#define _FD ((op>>6 ) & 0x1F)
#define _POS ((op>>6 ) & 0x1F)
#define _SIZE ((op>>11) & 0x1F)
#define RN(i) (currentDebugMIPS->GetRegName(0, i).c_str())
#define FN(i) (currentDebugMIPS->GetRegName(1, i).c_str())
//#define VN(i) (currentDebugMIPS->GetRegName(2, i).c_str())
namespace MIPSDis
{
std::string SignedHex(int i) {
char temp[32];
int offset = 0;
if (i < 0)
{
temp[0] = '-';
offset = 1;
i = -i;
}
snprintf(&temp[offset], sizeof(temp) - offset, "0x%X", i);
return temp;
}
void Dis_Generic(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
snprintf(out, outSize, "%s\t --- unknown ---", MIPSGetName(op));
}
void Dis_Cache(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int imm = SignExtend16ToS32(op & 0xFFFF);
int rs = _RS;
int func = (op >> 16) & 0x1F;
snprintf(out, outSize, "%s\tfunc=%i, %s(%s)", MIPSGetName(op), func, RN(rs), SignedHex(imm).c_str());
}
void Dis_mxc1(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int fs = _FS;
int rt = _RT;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t%s, %s", name, RN(rt), FN(fs));
}
void Dis_FPU3op(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int ft = _FT;
int fs = _FS;
int fd = _FD;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t%s, %s, %s", name, FN(fd), FN(fs), FN(ft));
}
void Dis_FPU2op(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int fs = _FS;
int fd = _FD;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t%s, %s", name, FN(fd), FN(fs));
}
void Dis_FPULS(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int offset = SignExtend16ToS32(op & 0xFFFF);
int ft = _FT;
int rs = _RS;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t%s, %s(%s)", name, FN(ft), SignedHex(offset).c_str(), RN(rs));
}
void Dis_FPUComp(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int fs = _FS;
int ft = _FT;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t%s, %s", name, FN(fs), FN(ft));
}
void Dis_FPUBranch(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
u32 off = pc;
int imm = SignExtend16ToS32(op & 0xFFFF) << 2;
off += imm + 4;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t->$%08x", name, off);
}
void Dis_RelBranch(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
u32 off = pc;
int imm = SignExtend16ToS32(op & 0xFFFF) << 2;
int rs = _RS;
off += imm + 4;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t%s, ->$%08x", name, RN(rs), off);
}
void Dis_Syscall(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
const u32 callno = (op>>6) & 0xFFFFF; //20 bits
const int funcNum = callno & 0xFFF;
const int moduleNum = (callno & 0xFF000) >> 12;
const char *funcName = GetHLEFuncName(moduleNum, funcNum);
if (funcName) {
snprintf(out, outSize, "syscall\t %s", funcName);
} else {
snprintf(out, outSize, "syscall\t %02x:%03x", moduleNum, funcNum);
}
}
void Dis_ToHiloTransfer(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int rs = _RS;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t%s", name, RN(rs));
}
void Dis_FromHiloTransfer(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int rd = _RD;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t%s", name, RN(rd));
}
void Dis_RelBranch2(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
u32 off = pc;
int imm = SignExtend16ToS32(op & 0xFFFF) << 2;
int rt = _RT;
int rs = _RS;
off += imm + 4;
const char *name = MIPSGetName(op);
int o = op>>26;
if (o==4 && rs == rt)//beq
snprintf(out, outSize, "b\t->$%08x", off);
else if (o==20 && rs == rt)//beql
snprintf(out, outSize, "bl\t->$%08x", off);
else
snprintf(out, outSize, "%s\t%s, %s, ->$%08x", name, RN(rs), RN(rt), off);
}
void Dis_IType(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
u32 uimm = op & 0xFFFF;
u32 suimm = SignExtend16ToU32(op);
s32 simm = SignExtend16ToS32(op);
int rt = _RT;
int rs = _RS;
const char *name = MIPSGetName(op);
switch (op >> 26)
{
case 8: //addi
case 9: //addiu
case 10: //slti
snprintf(out, outSize, "%s\t%s, %s, %s", name, RN(rt), RN(rs), SignedHex(simm).c_str());
break;
case 11: //sltiu
snprintf(out, outSize, "%s\t%s, %s, 0x%X", name, RN(rt), RN(rs), suimm);
break;
default:
snprintf(out, outSize, "%s\t%s, %s, 0x%X", name, RN(rt), RN(rs), uimm);
break;
}
}
void Dis_ori(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
u32 uimm = op & 0xFFFF;
int rt = _RT;
int rs = _RS;
const char *name = MIPSGetName(op);
if (rs == 0)
snprintf(out, outSize, "li\t%s, 0x%X", RN(rt), uimm);
else
snprintf(out, outSize, "%s\t%s, %s, 0x%X", name, RN(rt), RN(rs), uimm);
}
void Dis_IType1(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
u32 uimm = op & 0xFFFF;
int rt = _RT;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t%s, 0x%X", name, RN(rt), uimm);
}
void Dis_addi(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int imm = SignExtend16ToS32(op & 0xFFFF);
int rt = _RT;
int rs = _RS;
if (rs == 0)
snprintf(out, outSize, "li\t%s, %s", RN(rt), SignedHex(imm).c_str());
else
Dis_IType(op, pc, out, outSize);
}
void Dis_ITypeMem(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int imm = SignExtend16ToS32(op & 0xFFFF);
int rt = _RT;
int rs = _RS;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t%s, %s(%s)", name, RN(rt), SignedHex(imm).c_str(), RN(rs));
}
void Dis_RType2(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int rs = _RS;
int rd = _RD;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t%s, %s", name, RN(rd), RN(rs));
}
void Dis_RType3(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int rt = _RT;
int rs = _RS;
int rd = _RD;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t%s, %s, %s", name, RN(rd), RN(rs), RN(rt));
}
void Dis_addu(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int rt = _RT;
int rs = _RS;
int rd = _RD;
const char *name = MIPSGetName(op);
if (rs==0 && rt==0)
snprintf(out, outSize, "li\t%s, 0", RN(rd));
else if (rs == 0)
snprintf(out, outSize, "move\t%s, %s", RN(rd), RN(rt));
else if (rt == 0)
snprintf(out, outSize, "move\t%s, %s", RN(rd), RN(rs));
else
snprintf(out, outSize, "%s\t%s, %s, %s", name, RN(rd), RN(rs), RN(rt));
}
void Dis_ShiftType(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int rt = _RT;
int rs = _RS;
int rd = _RD;
int sa = (op>>6) & 0x1F;
const char *name = MIPSGetName(op);
if (((op & 0x3f) == 2) && rs == 1)
name = "rotr";
if (((op & 0x3f) == 6) && sa == 1)
name = "rotrv";
snprintf(out, outSize, "%s\t%s, %s, 0x%X", name, RN(rd), RN(rt), sa);
}
void Dis_VarShiftType(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int rt = _RT;
int rs = _RS;
int rd = _RD;
int sa = (op>>6) & 0x1F;
const char *name = MIPSGetName(op);
if (((op & 0x3f) == 6) && sa == 1)
name = "rotrv";
snprintf(out, outSize, "%s\t%s, %s, %s", name, RN(rd), RN(rt), RN(rs));
}
void Dis_MulDivType(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int rt = _RT;
int rs = _RS;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t%s, %s", name, RN(rs), RN(rt));
}
void Dis_Special3(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int rs = _RS;
int Rt = _RT;
int pos = _POS;
const char *name = MIPSGetName(op);
switch (op & 0x3f)
{
case 0x0: //ext
{
int size = _SIZE + 1;
snprintf(out, outSize, "%s\t%s, %s, 0x%X, 0x%X", name, RN(Rt), RN(rs), pos, size);
}
break;
case 0x4: // ins
{
int size = (_SIZE + 1) - pos;
snprintf(out, outSize, "%s\t%s, %s, 0x%X, 0x%X", name, RN(Rt), RN(rs), pos, size);
}
break;
}
}
void Dis_JumpType(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
u32 off = ((op & 0x03FFFFFF) << 2);
u32 addr = (pc & 0xF0000000) | off;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t->$%08x", name, addr);
}
void Dis_JumpRegType(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int rs = _RS;
int rd = _RD;
const char *name = MIPSGetName(op);
if ((op & 0x3f) == 9 && rd != MIPS_REG_RA)
snprintf(out, outSize, "%s\t%s,->%s", name, RN(rd), RN(rs));
else
snprintf(out, outSize, "%s\t->%s", name, RN(rs));
}
void Dis_Allegrex(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int rt = _RT;
int rd = _RD;
const char *name = MIPSGetName(op);
snprintf(out, outSize, "%s\t%s,%s", name, RN(rd), RN(rt));
}
void Dis_Allegrex2(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
int rt = _RT;
int rd = _RD;
const char *name = MIPSGetName(op);
snprintf(out, outSize,"%s\t%s,%s", name, RN(rd), RN(rt));
}
void Dis_Emuhack(MIPSOpcode op, uint32_t pc, char *out, size_t outSize) {
auto resolved = Memory::Read_Instruction(pc);
char disasm[256];
if (MIPS_IS_EMUHACK(resolved)) {
truncate_cpy(disasm, sizeof(disasm), "(invalid emuhack)");
} else {
MIPSDisAsm(resolved, pc, disasm, sizeof(disasm), true);
}
// Memory doesn't hold these, but the CPU cores substitute CallRepl for a replaced instruction.
switch (op.encoding >> 24) {
case 0x6a:
snprintf(out, outSize, "* replacement: %s", disasm);
break;
default:
snprintf(out, outSize, "* (invalid): %s", disasm);
break;
}
}
}