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[FAST486]

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Implement CMPXCHG.


svn path=/branches/ntvdm/; revision=60712
This commit is contained in:
Aleksandar Andrejevic 2013-10-19 18:56:58 +00:00
parent a98544e517
commit 75a0ca07a1
2 changed files with 160 additions and 2 deletions
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160
lib/fast486/extraops.c
View file

@ -214,8 +214,8 @@ Fast486ExtendedHandlers[FAST486_NUM_OPCODE_HANDLERS] =
NULL, // TODO: OPCODE 0xAD NOT IMPLEMENTED
NULL, // TODO: OPCODE 0xAE NOT IMPLEMENTED
NULL, // TODO: OPCODE 0xAF NOT IMPLEMENTED
NULL, // TODO: OPCODE 0xB0 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0xB1 NOT IMPLEMENTED
Fast486ExtOpcodeCmpXchgByte,
Fast486ExtOpcodeCmpXchg,
NULL, // TODO: OPCODE 0xB2 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0xB3 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0xB4 NOT IMPLEMENTED
@ -338,6 +338,162 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodePopGs)
return Fast486LoadSegment(State, FAST486_REG_GS, LOWORD(NewSelector));
}
FAST486_OPCODE_HANDLER(Fast486ExtOpcodeCmpXchgByte)
{
FAST486_MOD_REG_RM ModRegRm;
UCHAR Accumulator = State->GeneralRegs[FAST486_REG_EAX].LowByte;
UCHAR Source, Destination, Result;
BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;;
if (State->PrefixFlags & FAST486_PREFIX_ADSIZE)
{
/* The ADSIZE prefix toggles the size */
AddressSize = !AddressSize;
}
/* Get the operands */
if (!Fast486ParseModRegRm(State, AddressSize, &ModRegRm))
{
/* Exception occurred */
return FALSE;
}
/* Read the operands */
if (!Fast486ReadModrmByteOperands(State, &ModRegRm, &Source, &Destination))
{
/* Exception occurred */
return FALSE;
}
/* Compare AL with the destination */
Result = Accumulator - Destination;
/* Update the flags */
State->Flags.Cf = Accumulator < Destination;
State->Flags.Of = ((Accumulator & SIGN_FLAG_BYTE) != (Destination & SIGN_FLAG_BYTE))
&& ((Accumulator & SIGN_FLAG_BYTE) != (Result & SIGN_FLAG_BYTE));
State->Flags.Af = (Accumulator & 0x0F) < (Destination & 0x0F);
State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
State->Flags.Sf = (Result & SIGN_FLAG_BYTE) ? TRUE : FALSE;
State->Flags.Pf = Fast486CalculateParity(Result);
if (State->Flags.Zf)
{
/* Load the source operand into the destination */
return Fast486WriteModrmByteOperands(State, &ModRegRm, FALSE, Source);
}
else
{
/* Load the destination into AL */
State->GeneralRegs[FAST486_REG_EAX].LowByte = Destination;
}
/* Return success */
return TRUE;
}
FAST486_OPCODE_HANDLER(Fast486ExtOpcodeCmpXchg)
{
FAST486_MOD_REG_RM ModRegRm;
BOOLEAN OperandSize, AddressSize;
OperandSize = AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
if (State->PrefixFlags & FAST486_PREFIX_OPSIZE)
{
/* The OPSIZE prefix toggles the size */
OperandSize = !OperandSize;
}
if (State->PrefixFlags & FAST486_PREFIX_ADSIZE)
{
/* The ADSIZE prefix toggles the size */
AddressSize = !AddressSize;
}
/* Get the operands */
if (!Fast486ParseModRegRm(State, AddressSize, &ModRegRm))
{
/* Exception occurred */
return FALSE;
}
if (OperandSize)
{
ULONG Source, Destination, Result;
ULONG Accumulator = State->GeneralRegs[FAST486_REG_EAX].Long;
/* Read the operands */
if (!Fast486ReadModrmDwordOperands(State, &ModRegRm, &Source, &Destination))
{
/* Exception occurred */
return FALSE;
}
/* Compare EAX with the destination */
Result = Accumulator - Destination;
/* Update the flags */
State->Flags.Cf = Accumulator < Destination;
State->Flags.Of = ((Accumulator & SIGN_FLAG_LONG) != (Destination & SIGN_FLAG_LONG))
&& ((Accumulator & SIGN_FLAG_LONG) != (Result & SIGN_FLAG_LONG));
State->Flags.Af = (Accumulator & 0x0F) < (Destination & 0x0F);
State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
State->Flags.Sf = (Result & SIGN_FLAG_LONG) ? TRUE : FALSE;
State->Flags.Pf = Fast486CalculateParity(Result);
if (State->Flags.Zf)
{
/* Load the source operand into the destination */
return Fast486WriteModrmDwordOperands(State, &ModRegRm, FALSE, Source);
}
else
{
/* Load the destination into EAX */
State->GeneralRegs[FAST486_REG_EAX].Long = Destination;
}
}
else
{
USHORT Source, Destination, Result;
USHORT Accumulator = State->GeneralRegs[FAST486_REG_EAX].LowWord;
/* Read the operands */
if (!Fast486ReadModrmWordOperands(State, &ModRegRm, &Source, &Destination))
{
/* Exception occurred */
return FALSE;
}
/* Compare AX with the destination */
Result = Accumulator - Destination;
/* Update the flags */
State->Flags.Cf = Accumulator < Destination;
State->Flags.Of = ((Accumulator & SIGN_FLAG_WORD) != (Destination & SIGN_FLAG_WORD))
&& ((Accumulator & SIGN_FLAG_WORD) != (Result & SIGN_FLAG_WORD));
State->Flags.Af = (Accumulator & 0x0F) < (Destination & 0x0F);
State->Flags.Zf = (Result == 0) ? TRUE : FALSE;
State->Flags.Sf = (Result & SIGN_FLAG_WORD) ? TRUE : FALSE;
State->Flags.Pf = Fast486CalculateParity(Result);
if (State->Flags.Zf)
{
/* Load the source operand into the destination */
return Fast486WriteModrmWordOperands(State, &ModRegRm, FALSE, Source);
}
else
{
/* Load the destination into AX */
State->GeneralRegs[FAST486_REG_EAX].LowWord = Destination;
}
}
/* Return success */
return TRUE;
}
FAST486_OPCODE_HANDLER(Fast486ExtOpcodeConditionalJmp)
{
BOOLEAN Jump = FALSE;

2
lib/fast486/extraops.h
View file

@ -27,6 +27,8 @@ FAST486_OPCODE_HANDLER(Fast486ExtOpcodePushFs);
FAST486_OPCODE_HANDLER(Fast486ExtOpcodePopFs);
FAST486_OPCODE_HANDLER(Fast486ExtOpcodePushGs);
FAST486_OPCODE_HANDLER(Fast486ExtOpcodePopGs);
FAST486_OPCODE_HANDLER(Fast486ExtOpcodeCmpXchgByte);
FAST486_OPCODE_HANDLER(Fast486ExtOpcodeCmpXchg);
FAST486_OPCODE_HANDLER(Fast486ExtOpcodeConditionalJmp);
FAST486_OPCODE_HANDLER(Fast486ExtOpcodeConditionalSet);
FAST486_OPCODE_HANDLER(Fast486OpcodeExtended);