rjx-mirror/ARMeilleure/Instructions/InstEmitMemoryHelper.cs
FICTURE7 92f7f163ef
Improve static branch prediction along fast path for memory accesses (#1484)
* Improve static branch prediction along fast path for memory accesses

* Set PPTC interval version
2020-08-31 20:55:15 -03:00

621 lines
22 KiB
C#

using ARMeilleure.Decoders;
using ARMeilleure.IntermediateRepresentation;
using ARMeilleure.Translation;
using ARMeilleure.Translation.PTC;
using System;
using System.Reflection;
using static ARMeilleure.Instructions.InstEmitHelper;
using static ARMeilleure.IntermediateRepresentation.OperandHelper;
namespace ARMeilleure.Instructions
{
static class InstEmitMemoryHelper
{
private const int PageBits = 12;
private const int PageMask = (1 << PageBits) - 1;
private enum Extension
{
Zx,
Sx32,
Sx64
}
public static void EmitLoadZx(ArmEmitterContext context, Operand address, int rt, int size)
{
EmitLoad(context, address, Extension.Zx, rt, size);
}
public static void EmitLoadSx32(ArmEmitterContext context, Operand address, int rt, int size)
{
EmitLoad(context, address, Extension.Sx32, rt, size);
}
public static void EmitLoadSx64(ArmEmitterContext context, Operand address, int rt, int size)
{
EmitLoad(context, address, Extension.Sx64, rt, size);
}
private static void EmitLoad(ArmEmitterContext context, Operand address, Extension ext, int rt, int size)
{
bool isSimd = IsSimd(context);
if ((uint)size > (isSimd ? 4 : 3))
{
throw new ArgumentOutOfRangeException(nameof(size));
}
if (isSimd)
{
EmitReadVector(context, address, context.VectorZero(), rt, 0, size);
}
else
{
EmitReadInt(context, address, rt, size);
}
if (!isSimd && !(context.CurrOp is OpCode32 && rt == State.RegisterAlias.Aarch32Pc))
{
Operand value = GetInt(context, rt);
if (ext == Extension.Sx32 || ext == Extension.Sx64)
{
OperandType destType = ext == Extension.Sx64 ? OperandType.I64 : OperandType.I32;
switch (size)
{
case 0: value = context.SignExtend8 (destType, value); break;
case 1: value = context.SignExtend16(destType, value); break;
case 2: value = context.SignExtend32(destType, value); break;
}
}
SetInt(context, rt, value);
}
}
public static void EmitLoadSimd(
ArmEmitterContext context,
Operand address,
Operand vector,
int rt,
int elem,
int size)
{
EmitReadVector(context, address, vector, rt, elem, size);
}
public static void EmitStore(ArmEmitterContext context, Operand address, int rt, int size)
{
bool isSimd = IsSimd(context);
if ((uint)size > (isSimd ? 4 : 3))
{
throw new ArgumentOutOfRangeException(nameof(size));
}
if (isSimd)
{
EmitWriteVector(context, address, rt, 0, size);
}
else
{
EmitWriteInt(context, address, rt, size);
}
}
public static void EmitStoreSimd(
ArmEmitterContext context,
Operand address,
int rt,
int elem,
int size)
{
EmitWriteVector(context, address, rt, elem, size);
}
private static bool IsSimd(ArmEmitterContext context)
{
return context.CurrOp is IOpCodeSimd &&
!(context.CurrOp is OpCodeSimdMemMs ||
context.CurrOp is OpCodeSimdMemSs);
}
private static void EmitReadInt(ArmEmitterContext context, Operand address, int rt, int size)
{
Operand lblSlowPath = Label();
Operand lblEnd = Label();
Operand isUnalignedAddr = EmitAddressCheck(context, address, size);
context.BranchIfTrue(lblSlowPath, isUnalignedAddr);
Operand physAddr = EmitPtPointerLoad(context, address, lblSlowPath, write: false);
Operand value = null;
switch (size)
{
case 0: value = context.Load8 (physAddr); break;
case 1: value = context.Load16(physAddr); break;
case 2: value = context.Load (OperandType.I32, physAddr); break;
case 3: value = context.Load (OperandType.I64, physAddr); break;
}
SetInt(context, rt, value);
context.Branch(lblEnd);
context.MarkLabel(lblSlowPath);
EmitReadIntFallback(context, address, rt, size);
context.MarkLabel(lblEnd);
}
public static Operand EmitReadIntAligned(ArmEmitterContext context, Operand address, int size)
{
if ((uint)size > 4)
{
throw new ArgumentOutOfRangeException(nameof(size));
}
Operand isUnalignedAddr = EmitAddressCheck(context, address, size);
Operand lblFastPath = Label();
context.BranchIfFalse(lblFastPath, isUnalignedAddr);
// The call is not expected to return (it should throw).
context.Call(typeof(NativeInterface).GetMethod(nameof(NativeInterface.ThrowInvalidMemoryAccess)), address);
context.MarkLabel(lblFastPath);
Operand physAddr = EmitPtPointerLoad(context, address, null, write: false);
return size switch
{
0 => context.Load8(physAddr),
1 => context.Load16(physAddr),
2 => context.Load(OperandType.I32, physAddr),
3 => context.Load(OperandType.I64, physAddr),
_ => context.Load(OperandType.V128, physAddr)
};
}
private static void EmitReadVector(
ArmEmitterContext context,
Operand address,
Operand vector,
int rt,
int elem,
int size)
{
Operand lblSlowPath = Label();
Operand lblEnd = Label();
Operand isUnalignedAddr = EmitAddressCheck(context, address, size);
context.BranchIfTrue(lblSlowPath, isUnalignedAddr);
Operand physAddr = EmitPtPointerLoad(context, address, lblSlowPath, write: false);
Operand value = null;
switch (size)
{
case 0: value = context.VectorInsert8 (vector, context.Load8(physAddr), elem); break;
case 1: value = context.VectorInsert16(vector, context.Load16(physAddr), elem); break;
case 2: value = context.VectorInsert (vector, context.Load(OperandType.I32, physAddr), elem); break;
case 3: value = context.VectorInsert (vector, context.Load(OperandType.I64, physAddr), elem); break;
case 4: value = context.Load (OperandType.V128, physAddr); break;
}
context.Copy(GetVec(rt), value);
context.Branch(lblEnd);
context.MarkLabel(lblSlowPath);
EmitReadVectorFallback(context, address, vector, rt, elem, size);
context.MarkLabel(lblEnd);
}
private static Operand VectorCreate(ArmEmitterContext context, Operand value)
{
return context.VectorInsert(context.VectorZero(), value, 0);
}
private static void EmitWriteInt(ArmEmitterContext context, Operand address, int rt, int size)
{
Operand lblSlowPath = Label();
Operand lblEnd = Label();
Operand isUnalignedAddr = EmitAddressCheck(context, address, size);
context.BranchIfTrue(lblSlowPath, isUnalignedAddr);
Operand physAddr = EmitPtPointerLoad(context, address, lblSlowPath, write: true);
Operand value = GetInt(context, rt);
if (size < 3 && value.Type == OperandType.I64)
{
value = context.ConvertI64ToI32(value);
}
switch (size)
{
case 0: context.Store8 (physAddr, value); break;
case 1: context.Store16(physAddr, value); break;
case 2: context.Store (physAddr, value); break;
case 3: context.Store (physAddr, value); break;
}
context.Branch(lblEnd);
context.MarkLabel(lblSlowPath);
EmitWriteIntFallback(context, address, rt, size);
context.MarkLabel(lblEnd);
}
public static void EmitWriteIntAligned(ArmEmitterContext context, Operand address, Operand value, int size)
{
if ((uint)size > 4)
{
throw new ArgumentOutOfRangeException(nameof(size));
}
Operand isUnalignedAddr = EmitAddressCheck(context, address, size);
Operand lblFastPath = Label();
context.BranchIfFalse(lblFastPath, isUnalignedAddr);
// The call is not expected to return (it should throw).
context.Call(typeof(NativeInterface).GetMethod(nameof(NativeInterface.ThrowInvalidMemoryAccess)), address);
context.MarkLabel(lblFastPath);
Operand physAddr = EmitPtPointerLoad(context, address, null, write: true);
if (size < 3 && value.Type == OperandType.I64)
{
value = context.ConvertI64ToI32(value);
}
if (size == 0)
{
context.Store8(physAddr, value);
}
else if (size == 1)
{
context.Store16(physAddr, value);
}
else
{
context.Store(physAddr, value);
}
}
private static void EmitWriteVector(
ArmEmitterContext context,
Operand address,
int rt,
int elem,
int size)
{
Operand lblSlowPath = Label();
Operand lblEnd = Label();
Operand isUnalignedAddr = EmitAddressCheck(context, address, size);
context.BranchIfTrue(lblSlowPath, isUnalignedAddr);
Operand physAddr = EmitPtPointerLoad(context, address, lblSlowPath, write: true);
Operand value = GetVec(rt);
switch (size)
{
case 0: context.Store8 (physAddr, context.VectorExtract8(value, elem)); break;
case 1: context.Store16(physAddr, context.VectorExtract16(value, elem)); break;
case 2: context.Store (physAddr, context.VectorExtract(OperandType.I32, value, elem)); break;
case 3: context.Store (physAddr, context.VectorExtract(OperandType.I64, value, elem)); break;
case 4: context.Store (physAddr, value); break;
}
context.Branch(lblEnd);
context.MarkLabel(lblSlowPath);
EmitWriteVectorFallback(context, address, rt, elem, size);
context.MarkLabel(lblEnd);
}
public static Operand EmitAddressCheck(ArmEmitterContext context, Operand address, int size)
{
ulong addressCheckMask = ~((1UL << context.Memory.AddressSpaceBits) - 1);
addressCheckMask |= (1u << size) - 1;
return context.BitwiseAnd(address, Const(address.Type, (long)addressCheckMask));
}
public static Operand EmitPtPointerLoad(ArmEmitterContext context, Operand address, Operand lblSlowPath, bool write)
{
int ptLevelBits = context.Memory.AddressSpaceBits - 12; // 12 = Number of page bits.
int ptLevelSize = 1 << ptLevelBits;
int ptLevelMask = ptLevelSize - 1;
Operand pte = Ptc.State == PtcState.Disabled
? Const(context.Memory.PageTablePointer.ToInt64())
: Const(context.Memory.PageTablePointer.ToInt64(), true, Ptc.PageTablePointerIndex);
int bit = PageBits;
// Load page table entry from the page table.
// This was designed to support multi-level page tables of any size, however right
// now we only use flat page tables (so there's only one level).
// The page table entry contains the host address where the page is located.
// Additionally, the higher 16-bits of the host address may contain extra information
// used for write tracking, so this must be handled here aswell.
do
{
Operand addrPart = context.ShiftRightUI(address, Const(bit));
bit += ptLevelBits;
if (bit < context.Memory.AddressSpaceBits)
{
addrPart = context.BitwiseAnd(addrPart, Const(addrPart.Type, ptLevelMask));
}
Operand pteOffset = context.ShiftLeft(addrPart, Const(3));
if (pteOffset.Type == OperandType.I32)
{
pteOffset = context.ZeroExtend32(OperandType.I64, pteOffset);
}
Operand pteAddress = context.Add(pte, pteOffset);
pte = context.Load(OperandType.I64, pteAddress);
}
while (bit < context.Memory.AddressSpaceBits);
if (lblSlowPath != null)
{
context.BranchIf(lblSlowPath, pte, Const(0L), Comparison.LessOrEqual);
}
else
{
// When no label is provided to jump to a slow path if the address is invalid,
// we do the validation ourselves, and throw if needed.
if (write)
{
Operand lblNotWatched = Label();
// Is the page currently being monitored for modifications? If so we need to call MarkRegionAsModified.
context.BranchIf(lblNotWatched, pte, Const(0L), Comparison.GreaterOrEqual);
// Mark the region as modified. Size here doesn't matter as address is assumed to be size aligned here.
context.Call(typeof(NativeInterface).GetMethod(nameof(NativeInterface.MarkRegionAsModified)), address, Const(1UL));
context.MarkLabel(lblNotWatched);
}
Operand lblNonNull = Label();
// Skip exception if the PTE address is non-null (not zero).
context.BranchIfTrue(lblNonNull, pte);
// The call is not expected to return (it should throw).
context.Call(typeof(NativeInterface).GetMethod(nameof(NativeInterface.ThrowInvalidMemoryAccess)), address);
context.MarkLabel(lblNonNull);
pte = context.BitwiseAnd(pte, Const(0xffffffffffffUL));
}
Operand pageOffset = context.BitwiseAnd(address, Const(address.Type, PageMask));
if (pageOffset.Type == OperandType.I32)
{
pageOffset = context.ZeroExtend32(OperandType.I64, pageOffset);
}
return context.Add(pte, pageOffset);
}
private static void EmitReadIntFallback(ArmEmitterContext context, Operand address, int rt, int size)
{
MethodInfo info = null;
switch (size)
{
case 0: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.ReadByte)); break;
case 1: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.ReadUInt16)); break;
case 2: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.ReadUInt32)); break;
case 3: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.ReadUInt64)); break;
}
SetInt(context, rt, context.Call(info, address));
}
private static void EmitReadVectorFallback(
ArmEmitterContext context,
Operand address,
Operand vector,
int rt,
int elem,
int size)
{
MethodInfo info = null;
switch (size)
{
case 0: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.ReadByte)); break;
case 1: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.ReadUInt16)); break;
case 2: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.ReadUInt32)); break;
case 3: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.ReadUInt64)); break;
case 4: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.ReadVector128)); break;
}
Operand value = context.Call(info, address);
switch (size)
{
case 0: value = context.VectorInsert8 (vector, value, elem); break;
case 1: value = context.VectorInsert16(vector, value, elem); break;
case 2: value = context.VectorInsert (vector, value, elem); break;
case 3: value = context.VectorInsert (vector, value, elem); break;
}
context.Copy(GetVec(rt), value);
}
private static void EmitWriteIntFallback(ArmEmitterContext context, Operand address, int rt, int size)
{
MethodInfo info = null;
switch (size)
{
case 0: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.WriteByte)); break;
case 1: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.WriteUInt16)); break;
case 2: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.WriteUInt32)); break;
case 3: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.WriteUInt64)); break;
}
Operand value = GetInt(context, rt);
if (size < 3 && value.Type == OperandType.I64)
{
value = context.ConvertI64ToI32(value);
}
context.Call(info, address, value);
}
private static void EmitWriteVectorFallback(
ArmEmitterContext context,
Operand address,
int rt,
int elem,
int size)
{
MethodInfo info = null;
switch (size)
{
case 0: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.WriteByte)); break;
case 1: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.WriteUInt16)); break;
case 2: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.WriteUInt32)); break;
case 3: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.WriteUInt64)); break;
case 4: info = typeof(NativeInterface).GetMethod(nameof(NativeInterface.WriteVector128)); break;
}
Operand value = null;
if (size < 4)
{
switch (size)
{
case 0: value = context.VectorExtract8 (GetVec(rt), elem); break;
case 1: value = context.VectorExtract16(GetVec(rt), elem); break;
case 2: value = context.VectorExtract (OperandType.I32, GetVec(rt), elem); break;
case 3: value = context.VectorExtract (OperandType.I64, GetVec(rt), elem); break;
}
}
else
{
value = GetVec(rt);
}
context.Call(info, address, value);
}
private static Operand GetInt(ArmEmitterContext context, int rt)
{
return context.CurrOp is OpCode32 ? GetIntA32(context, rt) : GetIntOrZR(context, rt);
}
private static void SetInt(ArmEmitterContext context, int rt, Operand value)
{
if (context.CurrOp is OpCode32)
{
SetIntA32(context, rt, value);
}
else
{
SetIntOrZR(context, rt, value);
}
}
// ARM32 helpers.
public static Operand GetMemM(ArmEmitterContext context, bool setCarry = true)
{
switch (context.CurrOp)
{
case OpCode32MemRsImm op: return GetMShiftedByImmediate(context, op, setCarry);
case OpCode32MemReg op: return GetIntA32(context, op.Rm);
case OpCode32Mem op: return Const(op.Immediate);
case OpCode32SimdMemImm op: return Const(op.Immediate);
default: throw InvalidOpCodeType(context.CurrOp);
}
}
private static Exception InvalidOpCodeType(OpCode opCode)
{
return new InvalidOperationException($"Invalid OpCode type \"{opCode?.GetType().Name ?? "null"}\".");
}
public static Operand GetMShiftedByImmediate(ArmEmitterContext context, OpCode32MemRsImm op, bool setCarry)
{
Operand m = GetIntA32(context, op.Rm);
int shift = op.Immediate;
if (shift == 0)
{
switch (op.ShiftType)
{
case ShiftType.Lsr: shift = 32; break;
case ShiftType.Asr: shift = 32; break;
case ShiftType.Ror: shift = 1; break;
}
}
if (shift != 0)
{
setCarry &= false;
switch (op.ShiftType)
{
case ShiftType.Lsl: m = InstEmitAluHelper.GetLslC(context, m, setCarry, shift); break;
case ShiftType.Lsr: m = InstEmitAluHelper.GetLsrC(context, m, setCarry, shift); break;
case ShiftType.Asr: m = InstEmitAluHelper.GetAsrC(context, m, setCarry, shift); break;
case ShiftType.Ror:
if (op.Immediate != 0)
{
m = InstEmitAluHelper.GetRorC(context, m, setCarry, shift);
}
else
{
m = InstEmitAluHelper.GetRrxC(context, m, setCarry);
}
break;
}
}
return m;
}
}
}