[SOFT386]

Implement extended conditional jumps.


svn path=/branches/ntvdm/; revision=60699
This commit is contained in:
Aleksandar Andrejevic 2013-10-19 00:35:06 +00:00
parent 2095b2a844
commit 9b02129308
2 changed files with 139 additions and 16 deletions

View file

@ -31,6 +31,7 @@
#include <soft386.h>
#include "opcodes.h"
#include "common.h"
#include "extraops.h"
/* PUBLIC VARIABLES ***********************************************************/
@ -165,22 +166,22 @@ Soft386ExtendedHandlers[SOFT386_NUM_OPCODE_HANDLERS] =
NULL, // TODO: OPCODE 0x7D NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x7E NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x7F NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x80 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x81 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x82 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x83 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x84 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x85 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x86 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x87 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x88 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x89 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x8A NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x8B NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x8C NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x8D NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x8E NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x8F NOT IMPLEMENTED
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
Soft386ExtOpcodeConditionalJmp,
NULL, // TODO: OPCODE 0x90 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x91 NOT IMPLEMENTED
NULL, // TODO: OPCODE 0x92 NOT IMPLEMENTED
@ -297,6 +298,127 @@ Soft386ExtendedHandlers[SOFT386_NUM_OPCODE_HANDLERS] =
/* PUBLIC FUNCTIONS ***********************************************************/
SOFT386_OPCODE_HANDLER(Soft386ExtOpcodeConditionalJmp)
{
BOOLEAN Jump = FALSE;
LONG Offset = 0;
BOOLEAN Size = State->SegmentRegs[SOFT386_REG_CS].Size;
if (State->PrefixFlags & SOFT386_PREFIX_OPSIZE)
{
/* The OPSIZE prefix toggles the size */
Size = !Size;
}
if (State->PrefixFlags & SOFT386_PREFIX_LOCK)
{
/* Invalid prefix */
Soft386Exception(State, SOFT386_EXCEPTION_UD);
return FALSE;
}
/* Make sure this is the right instruction */
ASSERT((Opcode & 0xF0) == 0x80);
/* Fetch the offset */
if (Size)
{
if (!Soft386FetchDword(State, (PULONG)&Offset))
{
/* Exception occurred */
return FALSE;
}
}
else
{
SHORT Value;
if (!Soft386FetchWord(State, (PUSHORT)&Value))
{
/* Exception occurred */
return FALSE;
}
/* Sign-extend */
Offset = (LONG)Value;
}
switch ((Opcode & 0x0F) >> 1)
{
/* JO / JNO */
case 0:
{
Jump = State->Flags.Of;
break;
}
/* JC / JNC */
case 1:
{
Jump = State->Flags.Cf;
break;
}
/* JZ / JNZ */
case 2:
{
Jump = State->Flags.Zf;
break;
}
/* JBE / JNBE */
case 3:
{
Jump = State->Flags.Cf || State->Flags.Zf;
break;
}
/* JS / JNS */
case 4:
{
Jump = State->Flags.Sf;
break;
}
/* JP / JNP */
case 5:
{
Jump = State->Flags.Pf;
break;
}
/* JL / JNL */
case 6:
{
Jump = State->Flags.Sf != State->Flags.Of;
break;
}
/* JLE / JNLE */
case 7:
{
Jump = (State->Flags.Sf != State->Flags.Of) || State->Flags.Zf;
break;
}
}
if (Opcode & 1)
{
/* Invert the result */
Jump = !Jump;
}
if (Jump)
{
/* Move the instruction pointer */
State->InstPtr.Long += Offset;
}
/* Return success */
return TRUE;
}
SOFT386_OPCODE_HANDLER(Soft386OpcodeExtended)
{
UCHAR SecondOpcode;

View file

@ -23,6 +23,7 @@
#define _EXTRAOPS_H_
/* DEFINES ********************************************************************/
SOFT386_OPCODE_HANDLER(Soft386ExtOpcodeConditionalJmp);
SOFT386_OPCODE_HANDLER(Soft386OpcodeExtended);
#endif // _EXTRAOPS_H_