ppsspp/Core/MIPS/ARM/ArmAsm.cpp
2018-06-06 17:31:56 -07:00

273 lines
8.2 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 "ppsspp_config.h"
#if PPSSPP_ARCH(ARM)
#include "Core/MemMap.h"
#include "Core/MIPS/MIPS.h"
#include "Core/System.h"
#include "Core/CoreTiming.h"
#include "Common/MemoryUtil.h"
#include "Common/CPUDetect.h"
#include "Common/ArmEmitter.h"
#include "Core/MIPS/ARM/ArmJit.h"
#include "Core/MIPS/JitCommon/JitCommon.h"
using namespace ArmGen;
//static int temp32; // unused?
static const bool enableDebug = false;
static const bool disasm = false;
//static bool enableStatistics = false; //unused?
//The standard ARM calling convention allocates the 16 ARM registers as:
// r15 is the program counter.
// r14 is the link register. (The BL instruction, used in a subroutine call, stores the return address in this register).
// r13 is the stack pointer. (The Push/Pop instructions in "Thumb" operating mode use this register only).
// r12 is the Intra-Procedure-call scratch register.
// r4 to r11: used to hold local variables.
// r0 to r3: used to hold argument values passed to a subroutine, and also hold results returned from a subroutine.
// Mappable registers:
// R2, R3, R4, R5, R6, R8, R11
// STATIC ALLOCATION ARM:
// R10 : MIPS state
// R11 : Memory base pointer.
// R7 : Down counter
extern volatile CoreState coreState;
void ShowPC(u32 sp) {
ERROR_LOG(JIT, "ShowPC : %08x ArmSP : %08x", currentMIPS->pc, sp);
// Sleep(1);
}
void DisassembleArm(const u8 *data, int size);
// PLAN: no more block numbers - crazy opcodes just contain offset within
// dynarec buffer
// At this offset - 4, there is an int specifying the block number.
namespace MIPSComp {
using namespace ArmJitConstants;
void ArmJit::GenerateFixedCode() {
const u8 *start = AlignCodePage();
BeginWrite();
// LR == SCRATCHREG2 on ARM32 so it needs to be pushed.
restoreRoundingMode = AlignCode16(); {
PUSH(1, R_LR);
VMRS(SCRATCHREG2);
// Outside the JIT we run with round-to-nearest and flush0 off.
BIC(SCRATCHREG2, SCRATCHREG2, AssumeMakeOperand2((3 | 4) << 22));
VMSR(SCRATCHREG2);
POP(1, R_PC);
}
// Must preserve SCRATCHREG1 (R0), destroys SCRATCHREG2 (LR)
applyRoundingMode = AlignCode16(); {
PUSH(2, SCRATCHREG1, R_LR);
LDR(SCRATCHREG2, CTXREG, offsetof(MIPSState, fcr31));
TST(SCRATCHREG2, AssumeMakeOperand2(1 << 24));
AND(SCRATCHREG2, SCRATCHREG2, Operand2(3));
SetCC(CC_NEQ);
ADD(SCRATCHREG2, SCRATCHREG2, Operand2(4));
SetCC(CC_AL);
// We can skip if the rounding mode is nearest (0) and flush is not set.
// (as restoreRoundingMode cleared it out anyway)
CMP(SCRATCHREG2, Operand2(0));
FixupBranch skip = B_CC(CC_EQ);
// MIPS Rounding Mode: ARM Rounding Mode
// 0: Round nearest 0
// 1: Round to zero 3
// 2: Round up (ceil) 1
// 3: Round down (floor) 2
AND(SCRATCHREG1, SCRATCHREG2, Operand2(3));
CMP(SCRATCHREG1, Operand2(1));
SetCC(CC_EQ); ADD(SCRATCHREG2, SCRATCHREG2, Operand2(2));
SetCC(CC_GT); SUB(SCRATCHREG2, SCRATCHREG2, Operand2(1));
SetCC(CC_AL);
VMRS(SCRATCHREG1);
// Assume we're always in round-to-nearest mode beforehand.
// But we need to clear flush to zero in this case anyway.
BIC(SCRATCHREG1, SCRATCHREG1, AssumeMakeOperand2((3 | 4) << 22));
ORR(SCRATCHREG1, SCRATCHREG1, Operand2(SCRATCHREG2, ST_LSL, 22));
VMSR(SCRATCHREG1);
SetJumpTarget(skip);
POP(2, SCRATCHREG1, R_PC);
}
FlushLitPool();
enterDispatcher = AlignCode16();
DEBUG_LOG(JIT, "Base: %08x", (u32)Memory::base);
SetCC(CC_AL);
PUSH(9, R4, R5, R6, R7, R8, R9, R10, R11, R_LR);
// Take care to 8-byte align stack for function calls.
// We are misaligned here because of an odd number of args for PUSH.
// It's not like x86 where you need to account for an extra 4 bytes
// consumed by CALL.
SUB(R_SP, R_SP, 4);
// Now we are correctly aligned and plan to stay that way.
if (cpu_info.bNEON) {
VPUSH(D8, 8);
}
// Fixed registers, these are always kept when in Jit context.
// R8 is used to hold flags during delay slots. Not always needed.
// R13 cannot be used as it's the stack pointer.
// TODO: Consider statically allocating:
// * r2-r4
// Really starting to run low on registers already though...
// R11, R10, R9
MOVP2R(MEMBASEREG, Memory::base);
MOVP2R(CTXREG, mips_);
MOVP2R(JITBASEREG, GetBasePtr());
RestoreDowncount();
MovFromPC(R0);
outerLoopPCInR0 = GetCodePtr();
MovToPC(R0);
outerLoop = GetCodePtr();
SaveDowncount();
RestoreRoundingMode(true);
QuickCallFunction(R0, &CoreTiming::Advance);
ApplyRoundingMode(true);
RestoreDowncount();
FixupBranch skipToCoreStateCheck = B(); //skip the downcount check
dispatcherCheckCoreState = GetCodePtr();
// The result of slice decrementation should be in flags if somebody jumped here
// IMPORTANT - We jump on negative, not carry!!!
FixupBranch bailCoreState = B_CC(CC_MI);
SetJumpTarget(skipToCoreStateCheck);
MOVI2R(R0, (u32)(uintptr_t)&coreState);
LDR(R0, R0);
CMP(R0, 0);
FixupBranch badCoreState = B_CC(CC_NEQ);
FixupBranch skipToRealDispatch2 = B(); //skip the sync and compare first time
dispatcherPCInR0 = GetCodePtr();
// TODO: Do we always need to write PC to RAM here?
MovToPC(R0);
// At this point : flags = EQ. Fine for the next check, no need to jump over it.
dispatcher = GetCodePtr();
// The result of slice decrementation should be in flags if somebody jumped here
// IMPORTANT - We jump on negative, not carry!!!
FixupBranch bail = B_CC(CC_MI);
SetJumpTarget(skipToRealDispatch2);
dispatcherNoCheck = GetCodePtr();
// Debug
if (enableDebug) {
MOV(R0, R13);
QuickCallFunction(R1, (void *)&ShowPC);
}
LDR(R0, CTXREG, offsetof(MIPSState, pc));
// TODO: In practice, do we ever run code from uncached space (| 0x40000000)? If not, we can remove this BIC.
BIC(R0, R0, Operand2(0xC0, 4)); // &= 0x3FFFFFFF
LDR(R0, MEMBASEREG, R0);
AND(R1, R0, Operand2(0xFF, 4)); // rotation is to the right, in 2-bit increments.
BIC(R0, R0, Operand2(0xFF, 4));
CMP(R1, Operand2(MIPS_EMUHACK_OPCODE >> 24, 4));
SetCC(CC_EQ);
// IDEA - we have 26 bits, why not just use offsets from base of code?
// Another idea: Shift the bloc number left by two in the op, this would let us do
// LDR(R0, R9, R0); here, replacing the next instructions.
#ifdef IOS
// On iOS, R9 (JITBASEREG) is volatile. We have to reload it.
MOVI2R(JITBASEREG, (u32)(uintptr_t)GetBasePtr());
#endif
ADD(R0, R0, JITBASEREG);
B(R0);
SetCC(CC_AL);
// No block found, let's jit
SaveDowncount();
RestoreRoundingMode(true);
QuickCallFunction(R2, (void *)&MIPSComp::JitAt);
ApplyRoundingMode(true);
RestoreDowncount();
B(dispatcherNoCheck); // no point in special casing this
SetJumpTarget(bail);
SetJumpTarget(bailCoreState);
MOVI2R(R0, (u32)(uintptr_t)&coreState);
LDR(R0, R0);
CMP(R0, 0);
B_CC(CC_EQ, outerLoop);
SetJumpTarget(badCoreState);
SaveDowncount();
RestoreRoundingMode(true);
// Doing this above the downcount for better pipelining (slightly.)
if (cpu_info.bNEON) {
VPOP(D8, 8);
}
ADD(R_SP, R_SP, 4);
POP(9, R4, R5, R6, R7, R8, R9, R10, R11, R_PC); // Returns
// Uncomment if you want to see the output...
if (disasm) {
INFO_LOG(JIT, "THE DISASM ========================");
DisassembleArm(start, GetCodePtr() - start);
INFO_LOG(JIT, "END OF THE DISASM ========================");
}
// Don't forget to zap the instruction cache!
FlushLitPool();
FlushIcache();
// Let's spare the pre-generated code from unprotect-reprotect.
AlignCodePage();
EndWrite();
}
} // namespace MIPSComp
#endif // PPSSPP_ARCH(ARM)