Ryujinx/src/ARMeilleure/Instructions/InstEmitAlu32.cs
gdkchan 808803d97a
CPU: Fix PC alignment for ADR thumb instruction (#6613)
* Fix PC alignment for ADR thumb instruction

* PPTC version bump
2024-04-07 18:17:49 -03:00

945 lines
29 KiB
C#

using ARMeilleure.Decoders;
using ARMeilleure.IntermediateRepresentation;
using ARMeilleure.State;
using ARMeilleure.Translation;
using System.Diagnostics.CodeAnalysis;
using static ARMeilleure.Instructions.InstEmitAluHelper;
using static ARMeilleure.Instructions.InstEmitHelper;
using static ARMeilleure.IntermediateRepresentation.Operand.Factory;
namespace ARMeilleure.Instructions
{
[SuppressMessage("Style", "IDE0059: Remove unnecessary value assignment")]
static partial class InstEmit32
{
public static void Add(ArmEmitterContext context)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
Operand n = GetAluN(context);
Operand m = GetAluM(context, setCarry: false);
if (op.Rn == RegisterAlias.Aarch32Pc && op is OpCodeT32AluImm12)
{
// For ADR, PC is always 4 bytes aligned, even in Thumb mode.
n = context.BitwiseAnd(n, Const(~3u));
}
Operand res = context.Add(n, m);
if (ShouldSetFlags(context))
{
EmitNZFlagsCheck(context, res);
EmitAddsCCheck(context, n, res);
EmitAddsVCheck(context, n, m, res);
}
EmitAluStore(context, res);
}
public static void Adc(ArmEmitterContext context)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
Operand n = GetAluN(context);
Operand m = GetAluM(context, setCarry: false);
Operand res = context.Add(n, m);
Operand carry = GetFlag(PState.CFlag);
res = context.Add(res, carry);
if (ShouldSetFlags(context))
{
EmitNZFlagsCheck(context, res);
EmitAdcsCCheck(context, n, res);
EmitAddsVCheck(context, n, m, res);
}
EmitAluStore(context, res);
}
public static void And(ArmEmitterContext context)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
Operand n = GetAluN(context);
Operand m = GetAluM(context);
Operand res = context.BitwiseAnd(n, m);
if (ShouldSetFlags(context))
{
EmitNZFlagsCheck(context, res);
}
EmitAluStore(context, res);
}
public static void Bfc(ArmEmitterContext context)
{
IOpCode32AluBf op = (IOpCode32AluBf)context.CurrOp;
Operand d = GetIntA32(context, op.Rd);
Operand res = context.BitwiseAnd(d, Const(~op.DestMask));
SetIntA32(context, op.Rd, res);
}
public static void Bfi(ArmEmitterContext context)
{
IOpCode32AluBf op = (IOpCode32AluBf)context.CurrOp;
Operand n = GetIntA32(context, op.Rn);
Operand d = GetIntA32(context, op.Rd);
Operand part = context.BitwiseAnd(n, Const(op.SourceMask));
if (op.Lsb != 0)
{
part = context.ShiftLeft(part, Const(op.Lsb));
}
Operand res = context.BitwiseAnd(d, Const(~op.DestMask));
res = context.BitwiseOr(res, context.BitwiseAnd(part, Const(op.DestMask)));
SetIntA32(context, op.Rd, res);
}
public static void Bic(ArmEmitterContext context)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
Operand n = GetAluN(context);
Operand m = GetAluM(context);
Operand res = context.BitwiseAnd(n, context.BitwiseNot(m));
if (ShouldSetFlags(context))
{
EmitNZFlagsCheck(context, res);
}
EmitAluStore(context, res);
}
public static void Clz(ArmEmitterContext context)
{
Operand m = GetAluM(context, setCarry: false);
Operand res = context.CountLeadingZeros(m);
EmitAluStore(context, res);
}
public static void Cmp(ArmEmitterContext context)
{
Operand n = GetAluN(context);
Operand m = GetAluM(context, setCarry: false);
Operand res = context.Subtract(n, m);
EmitNZFlagsCheck(context, res);
EmitSubsCCheck(context, n, res);
EmitSubsVCheck(context, n, m, res);
}
public static void Cmn(ArmEmitterContext context)
{
Operand n = GetAluN(context);
Operand m = GetAluM(context, setCarry: false);
Operand res = context.Add(n, m);
EmitNZFlagsCheck(context, res);
EmitAddsCCheck(context, n, res);
EmitAddsVCheck(context, n, m, res);
}
public static void Eor(ArmEmitterContext context)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
Operand n = GetAluN(context);
Operand m = GetAluM(context);
Operand res = context.BitwiseExclusiveOr(n, m);
if (ShouldSetFlags(context))
{
EmitNZFlagsCheck(context, res);
}
EmitAluStore(context, res);
}
public static void Mov(ArmEmitterContext context)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
Operand m = GetAluM(context);
if (ShouldSetFlags(context))
{
EmitNZFlagsCheck(context, m);
}
EmitAluStore(context, m);
}
public static void Movt(ArmEmitterContext context)
{
IOpCode32AluImm16 op = (IOpCode32AluImm16)context.CurrOp;
Operand d = GetIntA32(context, op.Rd);
Operand imm = Const(op.Immediate << 16); // Immeditate value as top halfword.
Operand res = context.BitwiseAnd(d, Const(0x0000ffff));
res = context.BitwiseOr(res, imm);
EmitAluStore(context, res);
}
public static void Mul(ArmEmitterContext context)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
Operand n = GetAluN(context);
Operand m = GetAluM(context);
Operand res = context.Multiply(n, m);
if (ShouldSetFlags(context))
{
EmitNZFlagsCheck(context, res);
}
EmitAluStore(context, res);
}
public static void Mvn(ArmEmitterContext context)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
Operand m = GetAluM(context);
Operand res = context.BitwiseNot(m);
if (ShouldSetFlags(context))
{
EmitNZFlagsCheck(context, res);
}
EmitAluStore(context, res);
}
public static void Orr(ArmEmitterContext context)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
Operand n = GetAluN(context);
Operand m = GetAluM(context);
Operand res = context.BitwiseOr(n, m);
if (ShouldSetFlags(context))
{
EmitNZFlagsCheck(context, res);
}
EmitAluStore(context, res);
}
public static void Orn(ArmEmitterContext context)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
Operand n = GetAluN(context);
Operand m = GetAluM(context);
Operand res = context.BitwiseOr(n, context.BitwiseNot(m));
if (ShouldSetFlags(context))
{
EmitNZFlagsCheck(context, res);
}
EmitAluStore(context, res);
}
public static void Pkh(ArmEmitterContext context)
{
OpCode32AluRsImm op = (OpCode32AluRsImm)context.CurrOp;
Operand n = GetAluN(context);
Operand m = GetAluM(context);
Operand res;
bool tbform = op.ShiftType == ShiftType.Asr;
if (tbform)
{
res = context.BitwiseOr(context.BitwiseAnd(n, Const(0xFFFF0000)), context.BitwiseAnd(m, Const(0xFFFF)));
}
else
{
res = context.BitwiseOr(context.BitwiseAnd(m, Const(0xFFFF0000)), context.BitwiseAnd(n, Const(0xFFFF)));
}
EmitAluStore(context, res);
}
public static void Rbit(ArmEmitterContext context)
{
Operand m = GetAluM(context);
Operand res = EmitReverseBits32Op(context, m);
EmitAluStore(context, res);
}
public static void Rev(ArmEmitterContext context)
{
Operand m = GetAluM(context);
Operand res = context.ByteSwap(m);
EmitAluStore(context, res);
}
public static void Rev16(ArmEmitterContext context)
{
Operand m = GetAluM(context);
Operand res = EmitReverseBytes16_32Op(context, m);
EmitAluStore(context, res);
}
public static void Revsh(ArmEmitterContext context)
{
Operand m = GetAluM(context);
Operand res = EmitReverseBytes16_32Op(context, m);
EmitAluStore(context, context.SignExtend16(OperandType.I32, res));
}
public static void Rsc(ArmEmitterContext context)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
Operand n = GetAluN(context);
Operand m = GetAluM(context, setCarry: false);
Operand res = context.Subtract(m, n);
Operand borrow = context.BitwiseExclusiveOr(GetFlag(PState.CFlag), Const(1));
res = context.Subtract(res, borrow);
if (ShouldSetFlags(context))
{
EmitNZFlagsCheck(context, res);
EmitSbcsCCheck(context, m, n);
EmitSubsVCheck(context, m, n, res);
}
EmitAluStore(context, res);
}
public static void Rsb(ArmEmitterContext context)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
Operand n = GetAluN(context);
Operand m = GetAluM(context, setCarry: false);
Operand res = context.Subtract(m, n);
if (ShouldSetFlags(context))
{
EmitNZFlagsCheck(context, res);
EmitSubsCCheck(context, m, res);
EmitSubsVCheck(context, m, n, res);
}
EmitAluStore(context, res);
}
public static void Sadd8(ArmEmitterContext context)
{
EmitAddSub8(context, add: true, unsigned: false);
}
public static void Sbc(ArmEmitterContext context)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
Operand n = GetAluN(context);
Operand m = GetAluM(context, setCarry: false);
Operand res = context.Subtract(n, m);
Operand borrow = context.BitwiseExclusiveOr(GetFlag(PState.CFlag), Const(1));
res = context.Subtract(res, borrow);
if (ShouldSetFlags(context))
{
EmitNZFlagsCheck(context, res);
EmitSbcsCCheck(context, n, m);
EmitSubsVCheck(context, n, m, res);
}
EmitAluStore(context, res);
}
public static void Sbfx(ArmEmitterContext context)
{
IOpCode32AluBf op = (IOpCode32AluBf)context.CurrOp;
var msb = op.Lsb + op.Msb; // For this instruction, the msb is actually a width.
Operand n = GetIntA32(context, op.Rn);
Operand res = context.ShiftRightSI(context.ShiftLeft(n, Const(31 - msb)), Const(31 - op.Msb));
SetIntA32(context, op.Rd, res);
}
public static void Sdiv(ArmEmitterContext context)
{
EmitDiv(context, unsigned: false);
}
public static void Sel(ArmEmitterContext context)
{
IOpCode32AluReg op = (IOpCode32AluReg)context.CurrOp;
Operand n = GetIntA32(context, op.Rn);
Operand m = GetIntA32(context, op.Rm);
Operand ge0 = context.ZeroExtend8(OperandType.I32, context.Negate(GetFlag(PState.GE0Flag)));
Operand ge1 = context.ZeroExtend8(OperandType.I32, context.Negate(GetFlag(PState.GE1Flag)));
Operand ge2 = context.ZeroExtend8(OperandType.I32, context.Negate(GetFlag(PState.GE2Flag)));
Operand ge3 = context.Negate(GetFlag(PState.GE3Flag));
Operand mask = context.BitwiseOr(ge0, context.ShiftLeft(ge1, Const(8)));
mask = context.BitwiseOr(mask, context.ShiftLeft(ge2, Const(16)));
mask = context.BitwiseOr(mask, context.ShiftLeft(ge3, Const(24)));
Operand res = context.BitwiseOr(context.BitwiseAnd(n, mask), context.BitwiseAnd(m, context.BitwiseNot(mask)));
SetIntA32(context, op.Rd, res);
}
public static void Shadd8(ArmEmitterContext context)
{
EmitHadd8(context, unsigned: false);
}
public static void Shsub8(ArmEmitterContext context)
{
EmitHsub8(context, unsigned: false);
}
public static void Ssat(ArmEmitterContext context)
{
OpCode32Sat op = (OpCode32Sat)context.CurrOp;
EmitSat(context, -(1 << op.SatImm), (1 << op.SatImm) - 1);
}
public static void Ssat16(ArmEmitterContext context)
{
OpCode32Sat16 op = (OpCode32Sat16)context.CurrOp;
EmitSat16(context, -(1 << op.SatImm), (1 << op.SatImm) - 1);
}
public static void Ssub8(ArmEmitterContext context)
{
EmitAddSub8(context, add: false, unsigned: false);
}
public static void Sub(ArmEmitterContext context)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
Operand n = GetAluN(context);
Operand m = GetAluM(context, setCarry: false);
if (op.Rn == RegisterAlias.Aarch32Pc && op is OpCodeT32AluImm12)
{
// For ADR, PC is always 4 bytes aligned, even in Thumb mode.
n = context.BitwiseAnd(n, Const(~3u));
}
Operand res = context.Subtract(n, m);
if (ShouldSetFlags(context))
{
EmitNZFlagsCheck(context, res);
EmitSubsCCheck(context, n, res);
EmitSubsVCheck(context, n, m, res);
}
EmitAluStore(context, res);
}
public static void Sxtb(ArmEmitterContext context)
{
EmitSignExtend(context, true, 8);
}
public static void Sxtb16(ArmEmitterContext context)
{
EmitExtend16(context, true);
}
public static void Sxth(ArmEmitterContext context)
{
EmitSignExtend(context, true, 16);
}
public static void Teq(ArmEmitterContext context)
{
Operand n = GetAluN(context);
Operand m = GetAluM(context);
Operand res = context.BitwiseExclusiveOr(n, m);
EmitNZFlagsCheck(context, res);
}
public static void Tst(ArmEmitterContext context)
{
Operand n = GetAluN(context);
Operand m = GetAluM(context);
Operand res = context.BitwiseAnd(n, m);
EmitNZFlagsCheck(context, res);
}
public static void Uadd8(ArmEmitterContext context)
{
EmitAddSub8(context, add: true, unsigned: true);
}
public static void Ubfx(ArmEmitterContext context)
{
IOpCode32AluBf op = (IOpCode32AluBf)context.CurrOp;
var msb = op.Lsb + op.Msb; // For this instruction, the msb is actually a width.
Operand n = GetIntA32(context, op.Rn);
Operand res = context.ShiftRightUI(context.ShiftLeft(n, Const(31 - msb)), Const(31 - op.Msb));
SetIntA32(context, op.Rd, res);
}
public static void Udiv(ArmEmitterContext context)
{
EmitDiv(context, unsigned: true);
}
public static void Uhadd8(ArmEmitterContext context)
{
EmitHadd8(context, unsigned: true);
}
public static void Uhsub8(ArmEmitterContext context)
{
EmitHsub8(context, unsigned: true);
}
public static void Usat(ArmEmitterContext context)
{
OpCode32Sat op = (OpCode32Sat)context.CurrOp;
EmitSat(context, 0, op.SatImm == 32 ? (int)(~0) : (1 << op.SatImm) - 1);
}
public static void Usat16(ArmEmitterContext context)
{
OpCode32Sat16 op = (OpCode32Sat16)context.CurrOp;
EmitSat16(context, 0, (1 << op.SatImm) - 1);
}
public static void Usub8(ArmEmitterContext context)
{
EmitAddSub8(context, add: false, unsigned: true);
}
public static void Uxtb(ArmEmitterContext context)
{
EmitSignExtend(context, false, 8);
}
public static void Uxtb16(ArmEmitterContext context)
{
EmitExtend16(context, false);
}
public static void Uxth(ArmEmitterContext context)
{
EmitSignExtend(context, false, 16);
}
private static void EmitSignExtend(ArmEmitterContext context, bool signed, int bits)
{
IOpCode32AluUx op = (IOpCode32AluUx)context.CurrOp;
Operand m = GetAluM(context);
Operand res;
if (op.RotateBits == 0)
{
res = m;
}
else
{
Operand rotate = Const(op.RotateBits);
res = context.RotateRight(m, rotate);
}
switch (bits)
{
case 8:
res = (signed) ? context.SignExtend8(OperandType.I32, res) : context.ZeroExtend8(OperandType.I32, res);
break;
case 16:
res = (signed) ? context.SignExtend16(OperandType.I32, res) : context.ZeroExtend16(OperandType.I32, res);
break;
}
if (op.Add)
{
res = context.Add(res, GetAluN(context));
}
EmitAluStore(context, res);
}
private static void EmitExtend16(ArmEmitterContext context, bool signed)
{
IOpCode32AluUx op = (IOpCode32AluUx)context.CurrOp;
Operand m = GetAluM(context);
Operand res;
if (op.RotateBits == 0)
{
res = m;
}
else
{
Operand rotate = Const(op.RotateBits);
res = context.RotateRight(m, rotate);
}
Operand low16, high16;
if (signed)
{
low16 = context.SignExtend8(OperandType.I32, res);
high16 = context.SignExtend8(OperandType.I32, context.ShiftRightUI(res, Const(16)));
}
else
{
low16 = context.ZeroExtend8(OperandType.I32, res);
high16 = context.ZeroExtend8(OperandType.I32, context.ShiftRightUI(res, Const(16)));
}
if (op.Add)
{
Operand n = GetAluN(context);
Operand lowAdd, highAdd;
if (signed)
{
lowAdd = context.SignExtend16(OperandType.I32, n);
highAdd = context.SignExtend16(OperandType.I32, context.ShiftRightUI(n, Const(16)));
}
else
{
lowAdd = context.ZeroExtend16(OperandType.I32, n);
highAdd = context.ZeroExtend16(OperandType.I32, context.ShiftRightUI(n, Const(16)));
}
low16 = context.Add(low16, lowAdd);
high16 = context.Add(high16, highAdd);
}
res = context.BitwiseOr(
context.ZeroExtend16(OperandType.I32, low16),
context.ShiftLeft(context.ZeroExtend16(OperandType.I32, high16), Const(16)));
EmitAluStore(context, res);
}
private static void EmitDiv(ArmEmitterContext context, bool unsigned)
{
Operand n = GetAluN(context);
Operand m = GetAluM(context);
Operand zero = Const(m.Type, 0);
Operand divisorIsZero = context.ICompareEqual(m, zero);
Operand lblBadDiv = Label();
Operand lblEnd = Label();
context.BranchIfTrue(lblBadDiv, divisorIsZero);
if (!unsigned)
{
// ARM64 behaviour: If Rn == INT_MIN && Rm == -1, Rd = INT_MIN (overflow).
// TODO: tests to ensure A32 works the same
Operand intMin = Const(int.MinValue);
Operand minus1 = Const(-1);
Operand nIsIntMin = context.ICompareEqual(n, intMin);
Operand mIsMinus1 = context.ICompareEqual(m, minus1);
Operand lblGoodDiv = Label();
context.BranchIfFalse(lblGoodDiv, context.BitwiseAnd(nIsIntMin, mIsMinus1));
EmitAluStore(context, intMin);
context.Branch(lblEnd);
context.MarkLabel(lblGoodDiv);
}
Operand res = unsigned
? context.DivideUI(n, m)
: context.Divide(n, m);
EmitAluStore(context, res);
context.Branch(lblEnd);
context.MarkLabel(lblBadDiv);
EmitAluStore(context, zero);
context.MarkLabel(lblEnd);
}
private static void EmitAddSub8(ArmEmitterContext context, bool add, bool unsigned)
{
IOpCode32AluReg op = (IOpCode32AluReg)context.CurrOp;
Operand n = GetIntA32(context, op.Rn);
Operand m = GetIntA32(context, op.Rm);
Operand res = Const(0);
for (int byteSel = 0; byteSel < 4; byteSel++)
{
Operand shift = Const(byteSel * 8);
Operand nByte = context.ShiftRightUI(n, shift);
Operand mByte = context.ShiftRightUI(m, shift);
nByte = unsigned ? context.ZeroExtend8(OperandType.I32, nByte) : context.SignExtend8(OperandType.I32, nByte);
mByte = unsigned ? context.ZeroExtend8(OperandType.I32, mByte) : context.SignExtend8(OperandType.I32, mByte);
Operand resByte = add ? context.Add(nByte, mByte) : context.Subtract(nByte, mByte);
res = context.BitwiseOr(res, context.ShiftLeft(context.ZeroExtend8(OperandType.I32, resByte), shift));
SetFlag(context, PState.GE0Flag + byteSel, unsigned && add
? context.ShiftRightUI(resByte, Const(8))
: context.ShiftRightUI(context.BitwiseNot(resByte), Const(31)));
}
SetIntA32(context, op.Rd, res);
}
private static void EmitHadd8(ArmEmitterContext context, bool unsigned)
{
IOpCode32AluReg op = (IOpCode32AluReg)context.CurrOp;
Operand m = GetIntA32(context, op.Rm);
Operand n = GetIntA32(context, op.Rn);
Operand xor, res, carry;
// This relies on the equality x+y == ((x&y) << 1) + (x^y).
// Note that x^y always contains the LSB of the result.
// Since we want to calculate (x+y)/2, we can instead calculate (x&y) + ((x^y)>>1).
// We mask by 0x7F to remove the LSB so that it doesn't leak into the field below.
res = context.BitwiseAnd(m, n);
carry = context.BitwiseExclusiveOr(m, n);
xor = context.ShiftRightUI(carry, Const(1));
xor = context.BitwiseAnd(xor, Const(0x7F7F7F7Fu));
res = context.Add(res, xor);
if (!unsigned)
{
// Propagates the sign bit from (x^y)>>1 upwards by one.
carry = context.BitwiseAnd(carry, Const(0x80808080u));
res = context.BitwiseExclusiveOr(res, carry);
}
SetIntA32(context, op.Rd, res);
}
private static void EmitHsub8(ArmEmitterContext context, bool unsigned)
{
IOpCode32AluReg op = (IOpCode32AluReg)context.CurrOp;
Operand m = GetIntA32(context, op.Rm);
Operand n = GetIntA32(context, op.Rn);
Operand left, right, carry, res;
// This relies on the equality x-y == (x^y) - (((x^y)&y) << 1).
// Note that x^y always contains the LSB of the result.
// Since we want to calculate (x+y)/2, we can instead calculate ((x^y)>>1) - ((x^y)&y).
carry = context.BitwiseExclusiveOr(m, n);
left = context.ShiftRightUI(carry, Const(1));
right = context.BitwiseAnd(carry, m);
// We must now perform a partitioned subtraction.
// We can do this because minuend contains 7 bit fields.
// We use the extra bit in minuend as a bit to borrow from; we set this bit.
// We invert this bit at the end as this tells us if that bit was borrowed from.
res = context.BitwiseOr(left, Const(0x80808080));
res = context.Subtract(res, right);
res = context.BitwiseExclusiveOr(res, Const(0x80808080));
if (!unsigned)
{
// We then sign extend the result into this bit.
carry = context.BitwiseAnd(carry, Const(0x80808080));
res = context.BitwiseExclusiveOr(res, carry);
}
SetIntA32(context, op.Rd, res);
}
private static void EmitSat(ArmEmitterContext context, int intMin, int intMax)
{
OpCode32Sat op = (OpCode32Sat)context.CurrOp;
Operand n = GetIntA32(context, op.Rn);
int shift = DecodeImmShift(op.ShiftType, op.Imm5);
switch (op.ShiftType)
{
case ShiftType.Lsl:
if (shift == 32)
{
n = Const(0);
}
else
{
n = context.ShiftLeft(n, Const(shift));
}
break;
case ShiftType.Asr:
if (shift == 32)
{
n = context.ShiftRightSI(n, Const(31));
}
else
{
n = context.ShiftRightSI(n, Const(shift));
}
break;
}
Operand lblCheckLtIntMin = Label();
Operand lblNoSat = Label();
Operand lblEnd = Label();
context.BranchIfFalse(lblCheckLtIntMin, context.ICompareGreater(n, Const(intMax)));
SetFlag(context, PState.QFlag, Const(1));
SetIntA32(context, op.Rd, Const(intMax));
context.Branch(lblEnd);
context.MarkLabel(lblCheckLtIntMin);
context.BranchIfFalse(lblNoSat, context.ICompareLess(n, Const(intMin)));
SetFlag(context, PState.QFlag, Const(1));
SetIntA32(context, op.Rd, Const(intMin));
context.Branch(lblEnd);
context.MarkLabel(lblNoSat);
SetIntA32(context, op.Rd, n);
context.MarkLabel(lblEnd);
}
private static void EmitSat16(ArmEmitterContext context, int intMin, int intMax)
{
OpCode32Sat16 op = (OpCode32Sat16)context.CurrOp;
void SetD(int part, Operand value)
{
if (part == 0)
{
SetIntA32(context, op.Rd, context.ZeroExtend16(OperandType.I32, value));
}
else
{
SetIntA32(context, op.Rd, context.BitwiseOr(GetIntA32(context, op.Rd), context.ShiftLeft(value, Const(16))));
}
}
Operand n = GetIntA32(context, op.Rn);
Operand nLow = context.SignExtend16(OperandType.I32, n);
Operand nHigh = context.ShiftRightSI(n, Const(16));
for (int part = 0; part < 2; part++)
{
Operand nPart = part == 0 ? nLow : nHigh;
Operand lblCheckLtIntMin = Label();
Operand lblNoSat = Label();
Operand lblEnd = Label();
context.BranchIfFalse(lblCheckLtIntMin, context.ICompareGreater(nPart, Const(intMax)));
SetFlag(context, PState.QFlag, Const(1));
SetD(part, Const(intMax));
context.Branch(lblEnd);
context.MarkLabel(lblCheckLtIntMin);
context.BranchIfFalse(lblNoSat, context.ICompareLess(nPart, Const(intMin)));
SetFlag(context, PState.QFlag, Const(1));
SetD(part, Const(intMin));
context.Branch(lblEnd);
context.MarkLabel(lblNoSat);
SetD(part, nPart);
context.MarkLabel(lblEnd);
}
}
private static void EmitAluStore(ArmEmitterContext context, Operand value)
{
IOpCode32Alu op = (IOpCode32Alu)context.CurrOp;
EmitGenericAluStoreA32(context, op.Rd, ShouldSetFlags(context), value);
}
}
}