JitX64/RegAlloc: Improve documentation and improve method names

This commit is contained in:
MerryMage 2016-03-22 02:43:32 +00:00
parent 26c18cc21e
commit 550fef508e
5 changed files with 156 additions and 94 deletions

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@ -67,7 +67,7 @@ void JitX64::CondManager::CompileCond(const ConditionCode new_cond) {
cc = CC_NE;
break;
case ConditionCode::HI: { //c & !z
const X64Reg tmp = jit->reg_alloc.AllocAndLockTemp();
const X64Reg tmp = jit->reg_alloc.AllocTemp();
jit->code->MOVZX(64, 8, tmp, jit->MJitStateZFlag());
jit->code->CMP(8, jit->MJitStateCFlag(), R(tmp));
cc = CC_BE;
@ -75,7 +75,7 @@ void JitX64::CondManager::CompileCond(const ConditionCode new_cond) {
break;
}
case ConditionCode::LS: { //!c | z
const X64Reg tmp = jit->reg_alloc.AllocAndLockTemp();
const X64Reg tmp = jit->reg_alloc.AllocTemp();
jit->code->MOVZX(64, 8, tmp, jit->MJitStateZFlag());
jit->code->CMP(8, jit->MJitStateCFlag(), R(tmp));
cc = CC_A;
@ -83,7 +83,7 @@ void JitX64::CondManager::CompileCond(const ConditionCode new_cond) {
break;
}
case ConditionCode::GE: { // n == v
const X64Reg tmp = jit->reg_alloc.AllocAndLockTemp();
const X64Reg tmp = jit->reg_alloc.AllocTemp();
jit->code->MOVZX(64, 8, tmp, jit->MJitStateVFlag());
jit->code->CMP(8, jit->MJitStateNFlag(), R(tmp));
cc = CC_NE;
@ -91,7 +91,7 @@ void JitX64::CondManager::CompileCond(const ConditionCode new_cond) {
break;
}
case ConditionCode::LT: { // n != v
const X64Reg tmp = jit->reg_alloc.AllocAndLockTemp();
const X64Reg tmp = jit->reg_alloc.AllocTemp();
jit->code->MOVZX(64, 8, tmp, jit->MJitStateVFlag());
jit->code->CMP(8, jit->MJitStateNFlag(), R(tmp));
cc = CC_E;
@ -99,7 +99,7 @@ void JitX64::CondManager::CompileCond(const ConditionCode new_cond) {
break;
}
case ConditionCode::GT: { // !z & (n == v)
const X64Reg tmp = jit->reg_alloc.AllocAndLockTemp();
const X64Reg tmp = jit->reg_alloc.AllocTemp();
jit->code->MOVZX(64, 8, tmp, jit->MJitStateNFlag());
jit->code->XOR(8, R(tmp), jit->MJitStateVFlag());
jit->code->OR(8, R(tmp), jit->MJitStateZFlag());
@ -109,7 +109,7 @@ void JitX64::CondManager::CompileCond(const ConditionCode new_cond) {
break;
}
case ConditionCode::LE: { // z | (n != v)
X64Reg tmp = jit->reg_alloc.AllocAndLockTemp();
X64Reg tmp = jit->reg_alloc.AllocTemp();
jit->code->MOVZX(64, 8, tmp, jit->MJitStateNFlag());
jit->code->XOR(8, R(tmp), jit->MJitStateVFlag());
jit->code->OR(8, R(tmp), jit->MJitStateZFlag());

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@ -11,91 +11,50 @@ namespace JitX64 {
using namespace Gen;
void JitX64::CompileDataProcessingHelper(ArmReg Rn_index, ArmReg Rd_index, std::function<void(X64Reg)> body) {
// The major consideration is if Rn and/or Rd == R15.
if (Rd_index == 15) {
X64Reg Rd = reg_alloc.AllocAndLockTemp();
reg_alloc.LockArm(Rn_index);
if (Rn_index == 15) {
// TODO: In this case we can actually calculat the final result.
// We can also use CompileJumpToBB instead of having to use CompileReturnToDispatch.
code->MOV(32, R(Rd), Imm32(GetReg15Value()));
} else {
code->MOV(32, R(Rd), reg_alloc.ArmR(Rn_index));
}
body(Rd);
reg_alloc.UnlockArm(Rn_index);
code->MOV(32, MJitStateArmPC(), R(Rd));
reg_alloc.UnlockTemp(Rd);
} else if (Rn_index == 15) {
X64Reg Rd = reg_alloc.BindNoLoadAndLockArm(Rd_index);
reg_alloc.MarkDirty(Rd_index);
if (Rn_index == 15) {
X64Reg Rd = reg_alloc.WriteOnlyLockArm(Rd_index);
code->MOV(32, R(Rd), Imm32(GetReg15Value()));
body(Rd);
reg_alloc.UnlockArm(Rd_index);
} else if (Rn_index == Rd_index) {
X64Reg Rd = reg_alloc.BindAndLockArm(Rd_index);
} else if (Rn_index == Rd_index) { // Note: Rd_index cannot possibly be 15 in this case.
X64Reg Rd = reg_alloc.LoadAndLockArm(Rd_index);
reg_alloc.MarkDirty(Rd_index);
body(Rd);
reg_alloc.UnlockArm(Rd_index);
} else {
X64Reg Rd = reg_alloc.BindNoLoadAndLockArm(Rd_index);
reg_alloc.MarkDirty(Rd_index);
X64Reg Rd = reg_alloc.WriteOnlyLockArm(Rd_index);
reg_alloc.LockArm(Rn_index);
code->MOV(32, R(Rd), reg_alloc.ArmR(Rn_index));
body(Rd);
reg_alloc.UnlockArm(Rd_index);
reg_alloc.UnlockArm(Rn_index);
reg_alloc.UnlockArm(Rd_index);
}
}
void JitX64::CompileDataProcessingHelper_Reverse(ArmReg Rn_index, ArmReg Rd_index, std::function<void(X64Reg)> body) {
// The major consideration is if Rn and/or Rd == R15.
if (Rd_index != Rn_index) {
X64Reg Rd = INVALID_REG;
if (Rd_index == 15) {
Rd = reg_alloc.AllocAndLockTemp();
} else {
Rd = reg_alloc.BindNoLoadAndLockArm(Rd_index);
reg_alloc.MarkDirty(Rd_index);
}
X64Reg Rd = reg_alloc.WriteOnlyLockArm(Rd_index);
body(Rd);
if (Rd_index == 15) {
code->MOV(32, MJitStateArmPC(), R(Rd));
reg_alloc.UnlockTemp(Rd);
} else {
reg_alloc.UnlockArm(Rd_index);
}
reg_alloc.UnlockArm(Rd_index);
} else {
X64Reg tmp = reg_alloc.AllocAndLockTemp();
X64Reg tmp = reg_alloc.AllocTemp();
body(tmp);
// TODO: Efficiency: Could implement this as a register rebind instead of needing to MOV.
reg_alloc.LockArm(Rd_index);
reg_alloc.LockAndDirtyArm(Rd_index);
code->MOV(32, reg_alloc.ArmR(Rd_index), R(tmp));
reg_alloc.UnlockArm(Rd_index);
reg_alloc.UnlockTemp(tmp);
reg_alloc.UnlockTemp(tmp);
}
}
@ -228,7 +187,7 @@ void JitX64::MOV_imm(Cond cond, bool S, ArmReg Rd_index, int rotate, ArmImm8 imm
u32 immediate = rotr(imm8, rotate * 2);
if (Rd_index != 15) {
reg_alloc.LockArm(Rd_index);
reg_alloc.LockAndDirtyArm(Rd_index);
code->MOV(32, reg_alloc.ArmR(Rd_index), Imm32(immediate));
reg_alloc.UnlockArm(Rd_index);
} else {
@ -260,7 +219,7 @@ void JitX64::MVN_imm(Cond cond, bool S, ArmReg Rd_index, int rotate, ArmImm8 imm
u32 immediate = rotr(imm8, rotate * 2);
if (Rd_index != 15) {
reg_alloc.LockArm(Rd_index);
reg_alloc.LockAndDirtyArm(Rd_index);
code->MOV(32, reg_alloc.ArmR(Rd_index), Imm32(~immediate));
reg_alloc.UnlockArm(Rd_index);
} else {
@ -429,7 +388,7 @@ void JitX64::TEQ_imm(Cond cond, ArmReg Rn_index, int rotate, ArmImm8 imm8) {
u32 immediate = rotr(imm8, rotate * 2);
X64Reg Rn = reg_alloc.AllocAndLockTemp();
X64Reg Rn = reg_alloc.AllocTemp();
if (Rn_index == 15) {
code->MOV(32, R(Rn), Imm32(GetReg15Value()));
@ -462,10 +421,10 @@ void JitX64::TST_imm(Cond cond, ArmReg Rn_index, int rotate, ArmImm8 imm8) {
X64Reg Rn;
if (Rn_index == 15) {
Rn = reg_alloc.AllocAndLockTemp();
Rn = reg_alloc.AllocTemp();
code->MOV(32, R(Rn), Imm32(GetReg15Value()));
} else {
Rn = reg_alloc.BindAndLockArm(Rn_index);
Rn = reg_alloc.LoadAndLockArm(Rn_index);
}
code->TEST(32, R(Rn), Imm32(immediate));

View File

@ -3,6 +3,8 @@
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <cstring>
#include "common/assert.h"
#include "common/make_unique.h"
#include "common/x64/abi.h"

View File

@ -40,7 +40,7 @@ static Gen::OpArg MJitStateCpuReg(ArmReg arm_reg) {
static_assert(std::is_same<decltype(JitState::cpu_state), ARMul_State>::value, "JitState::cpu_state must be ARMul_State");
static_assert(std::is_same<decltype(ARMul_State::Reg), std::array<u32, 16>>::value, "ARMul_State::Reg must be std::array<u32, 16>");
ASSERT(arm_reg >= 0 && arm_reg <= 14);
ASSERT(arm_reg >= 0 && arm_reg <= 15);
return Gen::MDisp(jit_state_reg, offsetof(JitState, cpu_state) + offsetof(ARMul_State, Reg) + (arm_reg) * sizeof(u32));
}
@ -112,6 +112,8 @@ void RegAlloc::UnlockX64(Gen::X64Reg x64_reg) {
}
void RegAlloc::FlushArm(ArmReg arm_reg) {
ASSERT(arm_reg >= 0 && arm_reg <= 15);
ArmState& arm_state = arm_gpr[arm_reg];
Gen::X64Reg x64_reg = GetX64For(arm_reg);
X64State& x64_state = x64_gpr[x64_reg_to_index.at(x64_reg)];
@ -129,6 +131,8 @@ void RegAlloc::FlushArm(ArmReg arm_reg) {
}
void RegAlloc::LockArm(ArmReg arm_reg) {
ASSERT(arm_reg >= 0 && arm_reg <= 14); // Not valid for R15 (cannot read from it)
ArmState& arm_state = arm_gpr[arm_reg];
ASSERT(!arm_state.locked);
@ -145,7 +149,18 @@ void RegAlloc::LockArm(ArmReg arm_reg) {
}
}
Gen::X64Reg RegAlloc::BindMaybeLoadAndLockArm(ArmReg arm_reg, bool load) {
void RegAlloc::LockAndDirtyArm(ArmReg arm_reg) {
ASSERT(arm_reg >= 0 && arm_reg <= 14); // Not valid for R15 (cannot read from it)
ArmState& arm_state = arm_gpr[arm_reg];
LockArm(arm_reg);
if (arm_state.location.IsSimpleReg()) {
MarkDirty(arm_reg);
}
}
Gen::X64Reg RegAlloc::BindArmToX64(ArmReg arm_reg, bool load) {
ArmState& arm_state = arm_gpr[arm_reg];
ASSERT(!arm_state.locked);
@ -176,15 +191,27 @@ Gen::X64Reg RegAlloc::BindMaybeLoadAndLockArm(ArmReg arm_reg, bool load) {
return x64_reg;
}
Gen::X64Reg RegAlloc::BindAndLockArm(ArmReg arm_reg) {
return BindMaybeLoadAndLockArm(arm_reg, true);
Gen::X64Reg RegAlloc::LoadAndLockArm(ArmReg arm_reg) {
ASSERT(arm_reg >= 0 && arm_reg <= 14); // Not valid for R15 (cannot read from it)
const Gen::X64Reg x64_reg = BindArmToX64(arm_reg, true);
return x64_reg;
}
Gen::X64Reg RegAlloc::BindNoLoadAndLockArm(ArmReg arm_reg) {
return BindMaybeLoadAndLockArm(arm_reg, false);
Gen::X64Reg RegAlloc::WriteOnlyLockArm(ArmReg arm_reg) {
ASSERT(arm_reg >= 0 && arm_reg <= 15); // Valid for R15 (we're not reading from it)
const Gen::X64Reg x64_reg = BindArmToX64(arm_reg, false);
MarkDirty(arm_reg);
return x64_reg;
}
void RegAlloc::UnlockArm(ArmReg arm_reg) {
ASSERT(arm_reg >= 0 && arm_reg <= 15);
ArmState& arm_state = arm_gpr[arm_reg];
ASSERT(arm_state.locked);
@ -258,7 +285,7 @@ Gen::OpArg RegAlloc::ArmR(ArmReg arm_reg) {
return arm_state.location;
}
Gen::X64Reg RegAlloc::AllocAndLockTemp() {
Gen::X64Reg RegAlloc::AllocTemp() {
const Gen::X64Reg x64_reg = AllocReg();
X64State& x64_state = x64_gpr[x64_reg_to_index.at(x64_reg)];
x64_state.locked = true;
@ -277,7 +304,7 @@ void RegAlloc::UnlockTemp(Gen::X64Reg x64_reg) {
x64_state.state = X64State::State::Free;
}
Gen::X64Reg RegAlloc::BindAndLockMemoryMap() {
Gen::X64Reg RegAlloc::LoadMemoryMap() {
// First check to see if it exists.
for (auto i : x64_reg_to_index) {
X64State& x64_state = x64_gpr[i.second];
@ -327,7 +354,7 @@ void RegAlloc::AssertNoLocked() {
}
Gen::X64Reg RegAlloc::AllocReg() {
// TODO: This is terrible.
// TODO: Improve with an actual register allocator as this is terrible.
// First check to see if there anything free.
for (auto i : x64_reg_to_index) {

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@ -22,10 +22,30 @@ namespace JitX64 {
class RegAlloc final {
private:
struct ArmState {
Gen::OpArg location;
bool locked;
/**
* Where is the current value of this register?
* There are two options:
* - In an x64 register, in which case location.IsSimpleReg() == true.
* - In memory in ARMul_State, in which case location == MJitStateCpuReg(arm_reg).
*/
Gen::OpArg location = { 0, 0, Gen::INVALID_REG, Gen::INVALID_REG };
bool locked = false;
};
/**
* Possible states of X64State:
*
* Free (locked must be false): This x64 reg is free to be allocated for any purpose.
* Temp (locked must be true): This x64 reg is being used as a temporary for a calculation.
* DirtyArmReg (arm_reg is valid): This x64 reg holds the value of an ARM reg.
* It's value has been changed since being loaded from memory.
* This value must be flushed back to memory.
* CleanArmReg (arm_reg is valid): This x64 reg holds the value of an ARM reg.
* It's value has not been changed from when it's been loaded from memory.
* This value may be discarded.
* MemoryMap: This value holds a pointer to the ARM page table (current unimplemented).
* UserManuallyLocked: User has called LockX64 on this register. Must call UnlockX64 to unlock.
*/
struct X64State {
enum class State {
Free,
@ -36,9 +56,9 @@ private:
UserManuallyLocked
};
bool locked;
State state;
ArmReg arm_reg;
bool locked = false;
State state = State::Free;
ArmReg arm_reg = -1; ///< Only holds a valid value when state == DirtyArmReg / CleanArmReg
};
std::array<ArmState, 15> arm_gpr;
@ -47,9 +67,15 @@ private:
Gen::XEmitter* code = nullptr;
public:
RegAlloc() { Init(nullptr); }
/// Initialise register allocator (call compiling a basic block as it resets internal state)
void Init(Gen::XEmitter* emitter);
// Manually load and unlock x64 registers:
// This is required rarely. The most significant case is when shifting,
// because shift instructions must use the CL register.
/// Ensures that the state of that register is State::Free.
void FlushX64(Gen::X64Reg x64_reg);
/// Locks a register: Marks it as in-use so it isn't allocated.
@ -57,49 +83,97 @@ public:
/// Unlocks a register: Allows it to be used for allocation again.
void UnlockX64(Gen::X64Reg x64_reg);
// Working with ARM registers:
/**
* Locks an ARM register so it doesn't move.
* ARM reg may either be in a x64 reg or in memory.
* We're going to read from it only. (Use ArmR to do so.)
* Call UnlockArm when done.
*/
void LockArm(ArmReg arm_reg);
/**
* Locks an ARM register so it doesn't move.
* ARM reg may either be in a x64 reg or in memory.
* We're going to read and/or write to it. (Use ArmR to do so.)
* Call UnlockArm when done.
*/
void LockAndDirtyArm(ArmReg arm_reg);
/// Gets the current location of this ARM register. (ASSERTS IF NOT LOCKED!)
Gen::OpArg ArmR(ArmReg arm_reg);
/**
* Allocates a x64 register for an ARM register and ensure it's value is loaded into it.
* ARM reg is in an x64 reg.
* We're going to read from it only. (Call MarkDirty if you want to write to it.)
* Call UnlockArm when done.
*/
Gen::X64Reg LoadAndLockArm(ArmReg arm_reg);
/**
* Allocates a x64 register for an ARM register and doesn't bother loading it's value to it.
* ARM reg is in an x64 reg.
* We're going to write to it only. (DO NOT READ, WRITE-ONLY. Also MarkDirty has been called for you.)
* Call UnlockArm when done.
*/
Gen::X64Reg WriteOnlyLockArm(ArmReg arm_reg);
/**
* Marks an ARM register as dirty.
* If you don't mark something as dirty it won't be flushed back to memory.
* May only be called while an ARM register is locked.
*/
void MarkDirty(ArmReg arm_reg);
/// Unlock ARM register.
void UnlockArm(ArmReg arm_reg);
/// Ensures that this ARM register is not in an x64 register.
void FlushArm(ArmReg arm_reg);
/// Locks an ARM register so it doesn't move.
void LockArm(ArmReg arm_reg);
/// Allocates a x64 register for an ARM register and loads its value into it if necessary.
Gen::X64Reg BindAndLockArm(ArmReg arm_reg);
/// Allocates a x64 register for an ARM register but does not load a value.
Gen::X64Reg BindNoLoadAndLockArm(ArmReg arm_reg);
/// Unlock ARM register so the register is free to move and the underlying x64 register is available (if any).
void UnlockArm(ArmReg arm_reg);
/// Flush all ARM registers.
void FlushAllArm();
/// Marks an ARM register as dirty. If you don't mark something as dirty it won't be flushed.
void MarkDirty(ArmReg arm_reg);
/// Flush absolutely everything.
/**
* Flush absolutely everything.
* You MUST always flush everything:
* - just before a branch occurs
* - just before calling into the interpreter
* - just before calling a host function
* - just before returning to the dispatcher
* - just before jumping to a new BB
*/
void FlushEverything();
/// Gets the x64 register which corresponds to that ARM register. (ASSERTS IF NOT IN A x64 REG OR NOT LOCKED!)
Gen::X64Reg GetX64For(ArmReg arm_reg);
/// Gets the current location of this ARM register. (ASSERTS IF NOT LOCKED!)
Gen::OpArg ArmR(ArmReg arm_reg);
// Temporaries:
/// Allocates a temporary register
Gen::X64Reg AllocAndLockTemp();
Gen::X64Reg AllocTemp();
/// Releases a temporary register
void UnlockTemp(Gen::X64Reg x64_reg);
// Page table:
/// Gets the x64 register with the address of the memory map in it. Allocates one if one doesn't already exist.
Gen::X64Reg BindAndLockMemoryMap();
Gen::X64Reg LoadMemoryMap();
/// Releases the memory map register.
void UnlockMemoryMap(Gen::X64Reg x64_reg);
// JitState pointer:
/// Returns the register in which the JitState pointer is stored.
Gen::X64Reg JitStateReg();
// Debug:
void AssertNoLocked();
private:
/// INTERNAL: Allocates a register that is free. Flushes registers that are not locked if necessary.
Gen::X64Reg AllocReg();
/// INTERNAL: Implementation of BindNoLoadAndLockArm and BindAndLockArm
Gen::X64Reg BindMaybeLoadAndLockArm(ArmReg arm_reg, bool load);
/// INTERNAL: Binds an ARM register to an X64 register. Retrieves binding if already bound.
Gen::X64Reg BindArmToX64(ArmReg arm_reg, bool load);
};
}