/*++
Copyright (c) 1994 Microsoft Corporation
Module Name:
operand.c
Abstract:
This module implements the operand functions necessary to decode x86
instruction operands.
Author:
David N. Cutler (davec) 3-Sep-1994
Environment:
Kernel mode only.
Revision History:
--*/
#include "nthal.h"
#include "emulate.h"
ULONG
XmPushPopSegment (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG Index;
//
// Push or pop segment register.
//
Index = P->OpcodeControl.FormatType;
P->DataType = WORD_DATA;
if (P->FunctionIndex == X86_PUSH_OP) {
XmSetSourceValue(P, (PVOID)(&P->SegmentRegister[Index]));
} else {
XmSetDestinationValue(P, (PVOID)(&P->SegmentRegister[Index]));
}
return TRUE;
}
ULONG
XmLoadSegment (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG Index;
ULONG DataType;
PVOID Operand;
ULONG Number;
//
// Load a segment register and a displacement value into register.
//
Index = P->OpcodeControl.FormatType;
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
Operand = XmEvaluateAddressSpecifier(P, &Number);
if (!Operand) return FALSE;
if (P->RegisterOffsetAddress != FALSE) {
longjmp(&P->JumpBuffer[0], XM_ILLEGAL_REGISTER_SPECIFIER);
}
XmSetSourceValue(P, Operand);
DataType = P->DataType;
P->DataType = WORD_DATA;
Operand = XmGetOffsetAddress(P, P->Offset + DataType + 1);
XmSetDestinationValue(P, Operand);
P->SegmentRegister[Index - FormatLoadSegmentES] = P->DstValue.Word;
P->DataType = DataType;
P->DstLong = (ULONG UNALIGNED *)(&P->Gpr[Number].Exx);
return TRUE;
}
ULONG
XmGroup1General (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
//
// Group 1 opcodes with general operand specifier and a direction
// bit.
//
XmSetDataType(P);
Operand = XmEvaluateAddressSpecifier(P, &Number);
if (!Operand) return FALSE;
if ((P->CurrentOpcode & DIRECTION_BIT) == 0) {
XmSetDestinationValue(P, Operand);
XmSetSourceValue(P, XmGetRegisterAddress(P, Number));
} else {
XmSetDestinationValue(P, XmGetRegisterAddress(P, Number));
XmSetSourceValue(P, Operand);
}
return TRUE;
}
ULONG
XmGroup1Immediate (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
ULONG Source;
//
// Group 1 opcode with general operand specifier and an immediate
// operand.
//
XmSetDataType(P);
Operand = XmEvaluateAddressSpecifier(P, &Number);
Source = XmGetImmediateSourceValue(P, P->CurrentOpcode & SIGN_BIT);
XmSetDestinationValue(P, Operand);
XmSetImmediateSourceValue(P, Source);
P->FunctionIndex += Number;
return TRUE;
}
ULONG
XmGroup2By1 (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
ULONG Source;
//
// Group 2 shift opcodes with a general operand specifier and a
// shift count of 1.
//
XmSetDataType(P);
Operand = XmEvaluateAddressSpecifier(P, &Number);
if (!Operand) return FALSE;
Source = 1;
XmSetImmediateSourceValue(P, Source);
XmSetDestinationValue(P, Operand);
P->FunctionIndex += Number;
return TRUE;
}
ULONG
XmGroup2ByCL (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
ULONG Source;
//
// Group 2 shift opcodes with a general operand specifier and a
// CL shift count.
//
XmSetDataType(P);
Operand = XmEvaluateAddressSpecifier(P, &Number);
if (!Operand) return FALSE;
Source = (ULONG)P->Gpr[CL].Xl & 0x1f;
XmSetImmediateSourceValue(P, Source);
XmSetDestinationValue(P, Operand);
P->FunctionIndex += Number;
return TRUE;
}
ULONG
XmGroup2ByByte (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
ULONG Source;
//
// Group 2 shift opcodes with a general operand specifier and a
// byte immediate shift count.
//
XmSetDataType(P);
Operand = XmEvaluateAddressSpecifier(P, &Number);
Source = XmGetByteImmediate(P) & 0x1f;
XmSetImmediateSourceValue(P, Source);
XmSetDestinationValue(P, Operand);
P->FunctionIndex += Number;
return TRUE;
}
ULONG
XmGroup3General (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
ULONG Source;
//
// Group 3 opcodes with general operand specifier.
//
// N.B. The test operator for this group has an immediate operand
// and the multiply and divide operators use the accumulator
// as a source. The not and neg operators are unary.
//
XmSetDataType(P);
Operand = XmEvaluateAddressSpecifier(P, &Number);
P->FunctionIndex += Number;
if (P->FunctionIndex == X86_TEST_OP) {
Source = XmGetImmediateSourceValue(P, 0);
XmSetDestinationValue(P, Operand);
XmSetImmediateSourceValue(P, Source);
} else {
//
// If the operation is a mulitply or divide, then there is an
// implied operand which is AL, AX, or EAX. If the operation is
// a divide, then there is an additional implied operand which
// is AH, DX, or EDX.
//
if ((Number & 0x4) != 0) {
if ((Number & 0x2) == 0) {
XmSetDestinationValue(P, (PVOID)(&P->Gpr[EAX].Exx));
} else {
P->DstLong = (UNALIGNED ULONG *)(&P->Gpr[EAX].Exx);
}
XmSetSourceValue(P, Operand);
} else {
XmSetDestinationValue(P, Operand);
}
}
return TRUE;
}
ULONG
XmGroup45General (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG DataType;
PVOID Operand;
ULONG Number;
//
// Group 4 and group 5 unary opcodes with general operand specifier.
//
XmSetDataType(P);
Operand = XmEvaluateAddressSpecifier(P, &Number);
if (!Operand) return FALSE;
if (P->OpcodeControl.FormatType == FormatGroup4General) {
Number &= 0x1;
}
P->FunctionIndex += Number;
if (P->FunctionIndex == X86_PUSH_OP) {
XmSetSourceValue(P, Operand);
} else {
//
// If the operation is a call or jump that specifies a segment,
// then get the segment value.
//
XmSetDestinationValue(P, Operand);
if ((Number == 3) || (Number == 5)) {
if (P->RegisterOffsetAddress != FALSE) {
longjmp(&P->JumpBuffer[0], XM_ILLEGAL_REGISTER_SPECIFIER);
}
DataType = P->DataType;
P->DataType = WORD_DATA;
Operand = XmGetOffsetAddress(P, P->Offset + DataType + 1);
XmSetSourceValue(P, Operand);
P->DstSegment = P->SrcValue.Word;
P->DataType = DataType;
}
}
return TRUE;
}
ULONG
XmGroup8BitOffset (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Offset;
ULONG Number;
//
// Bit test opcodes with an immediate bit offset and a memory or
// register operand.
//
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
Operand = XmEvaluateAddressSpecifier(P, &Number);
Offset = XmGetByteImmediate(P);
XmSetImmediateSourceValue(P, Offset);
if (P->RegisterOffsetAddress == FALSE) {
if (P->DataType == LONG_DATA) {
Offset = (P->SrcValue.Long >> 5) << 2;
} else {
Offset = (P->SrcValue.Long >> 4) << 1;
}
Operand = XmGetOffsetAddress(P, Offset + P->Offset);
}
if (P->DataType == LONG_DATA) {
P->SrcValue.Long &= 0x1f;
} else {
P->SrcValue.Long &= 0xf;
}
XmSetDestinationValue(P, Operand);
P->FunctionIndex += (Number & 0x3);
return TRUE;
}
ULONG
XmOpcodeRegister (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG Number;
//
// Unary opodes with a general register encoded in the low
// 3 bits of the opcode value.
//
Number = P->CurrentOpcode & 0x7;
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
if (P->FunctionIndex == X86_PUSH_OP) {
XmSetSourceValue(P, (PVOID)(&P->Gpr[Number].Exx));
} else {
XmSetDestinationValue(P, (PVOID)(&P->Gpr[Number].Exx));
}
return TRUE;
}
ULONG
XmLongJump (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG Offset;
//
// Long jump with opcode containing the control for conditional
// jumps. The destination of the jump is stored in the destination
// value and the jump control is stored in the sources value.
//
if (P->OpsizePrefixActive != FALSE) {
Offset = XmGetLongImmediate(P);
P->DstValue.Long = P->Eip + Offset;
} else {
Offset = XmGetWordImmediate(P);
P->DstValue.Long = (USHORT)(Offset + P->Eip);
}
P->SrcValue.Long = P->CurrentOpcode & 0xf;
return TRUE;
}
ULONG
XmShortJump (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG Offset;
//
// Short jump with opcode containing the control for conditional
// jumps. The destination of the jump is stored in the destination
// value and the jump control is stored in the sources value.
//
Offset = (ULONG)XmGetSignedByteImmediateToWord(P);
P->DstValue.Long = (USHORT)(Offset + P->Eip);
P->SrcValue.Long = P->CurrentOpcode & 0xf;
return TRUE;
}
ULONG
XmSetccByte (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG Number;
//
// General byte destination with reg field ignored and the opcode
// containing the condition control.
//
P->DataType = BYTE_DATA;
P->DstByte = (UCHAR UNALIGNED *)XmEvaluateAddressSpecifier(P, &Number);
P->SrcValue.Long = P->CurrentOpcode & 0xf;
return TRUE;
}
ULONG
XmAccumImmediate (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG Source;
//
// Accumulator destination and immediate source operands.
//
XmSetDataType(P);
Source = XmGetImmediateSourceValue(P, 0);
XmSetDestinationValue(P, (PVOID)(&P->Gpr[EAX].Exx));
XmSetImmediateSourceValue(P, Source);
return TRUE;
}
ULONG
XmAccumRegister (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG Number;
//
// Accumulator destination and a general register source encoded in
// the low 3-bits of the opcode value.
//
Number = P->CurrentOpcode & 0x7;
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
XmSetSourceValue(P, (PVOID)(&P->Gpr[Number].Exx));
XmSetDestinationValue(P, (PVOID)(&P->Gpr[EAX].Exx));
return TRUE;
}
ULONG
XmMoveGeneral (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
//
// Move opcodes with general operand specifier and a direction bit.
//
XmSetDataType(P);
Operand = XmEvaluateAddressSpecifier(P, &Number);
if (!Operand) return FALSE;
if ((P->CurrentOpcode & DIRECTION_BIT) == 0) {
P->DstLong = (ULONG UNALIGNED *)Operand;
XmSetSourceValue(P, XmGetRegisterAddress(P, Number));
} else {
P->DstLong = (ULONG UNALIGNED *)XmGetRegisterAddress(P, Number);
XmSetSourceValue(P, Operand);
}
return TRUE;
}
ULONG
XmMoveImmediate (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
ULONG Source;
//
// Move opcodes with general operand specifier and an immediate
// operand.
//
XmSetDataType(P);
Operand = XmEvaluateAddressSpecifier(P, &Number);
P->DstLong = (ULONG UNALIGNED *)Operand;
Source = XmGetImmediateSourceValue(P, 0);
XmSetImmediateSourceValue(P, Source);
return TRUE;
}
ULONG
XmMoveRegImmediate (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG Number;
//
// Move register immediate opcodes with a general register encoded
// in the low 3-bits of the opcode value and an immediate operand.
//
Number = P->CurrentOpcode & 0x7;
if ((P->CurrentOpcode & 0x8) == 0) {
P->DataType = BYTE_DATA;
} else {
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
}
P->DstLong = (ULONG UNALIGNED *)XmGetRegisterAddress(P, Number);
XmSetImmediateSourceValue(P, XmGetImmediateSourceValue(P, 0));
return TRUE;
}
ULONG
XmSegmentOffset (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Offset;
//
// Move opcodes with an implied accumlator operand and an immediate
// segment offset and a direction bit.
//
XmSetDataType(P);
if (P->OpaddrPrefixActive != FALSE) {
Offset = XmGetLongImmediate(P);
} else {
Offset = XmGetWordImmediate(P);
}
Operand = XmGetOffsetAddress(P, Offset);
if ((P->CurrentOpcode & DIRECTION_BIT) == 0) {
P->DstLong = (ULONG UNALIGNED *)(&P->Gpr[EAX].Exx);
XmSetSourceValue(P, Operand);
} else {
P->DstLong = (ULONG UNALIGNED *)Operand;
XmSetSourceValue(P, &P->Gpr[EAX].Exx);
}
return TRUE;
}
ULONG
XmMoveSegment (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
//
// Move segment opcodes with general operand specifier and a direction
// bit.
//
P->DataType = WORD_DATA;
Operand = XmEvaluateAddressSpecifier(P, &Number);
if (!Operand) return FALSE;
if ((P->CurrentOpcode & DIRECTION_BIT) == 0) {
P->DstLong = (ULONG UNALIGNED *)Operand;
XmSetSourceValue(P, (PVOID)(&P->SegmentRegister[Number]));
} else {
P->DstLong = (ULONG UNALIGNED *)(&P->SegmentRegister[Number]);
XmSetSourceValue(P, Operand);
}
return TRUE;
}
ULONG
XmMoveXxGeneral (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
//
// Move zero or sign extended opcodes with general operand specifier.
//
if ((P->CurrentOpcode & WIDTH_BIT) == 0) {
P->DataType = BYTE_DATA;
} else {
P->DataType = WORD_DATA;
}
Operand = XmEvaluateAddressSpecifier(P, &Number);
if (!Operand) return FALSE;
XmSetSourceValue(P, Operand);
if (P->DataType == BYTE_DATA) {
if ((P->CurrentOpcode & 0x8) == 0) {
P->SrcValue.Long = (ULONG)P->SrcValue.Byte;
} else {
P->SrcValue.Long = (ULONG)((LONG)((SCHAR)P->SrcValue.Byte));
}
} else {
if ((P->CurrentOpcode & 0x8) == 0) {
P->SrcValue.Long = (ULONG)P->SrcValue.Word;
} else {
P->SrcValue.Long = (ULONG)((LONG)((SHORT)P->SrcValue.Word));
}
}
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
P->SrcValue.Long &= 0xffff;
}
P->DstLong = (UNALIGNED ULONG *)(&P->Gpr[Number].Exx);
return TRUE;
}
ULONG
XmFlagsRegister (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
//
// Flags register source or destination with a stack source or
// destination.
//
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
if (P->FunctionIndex == X86_PUSH_OP) {
XmSetSourceValue(P, (PVOID)(&P->AllFlags));
} else {
XmSetDestinationValue(P, (PVOID)(&P->AllFlags));
}
return TRUE;
}
ULONG
XmPushImmediate (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG Source;
//
// Push opcode with an immediate operand.
//
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
Source = XmGetImmediateSourceValue(P, P->CurrentOpcode & SIGN_BIT);
XmSetImmediateSourceValue(P, Source);
return TRUE;
}
ULONG
XmPopGeneral (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
//
// Pop opcode with a general specifier.
//
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
Operand = XmEvaluateAddressSpecifier(P, &Number);
if (!Operand) return FALSE;
XmSetDestinationValue(P, Operand);
return TRUE;
}
ULONG
XmImulImmediate (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG Number;
PVOID Operand;
ULONG Source;
//
// Multiply signed opcode with a general specifier and an immediate
// operand.
//
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
Operand = XmEvaluateAddressSpecifier(P, &Number);
Source = XmGetImmediateSourceValue(P, P->CurrentOpcode & SIGN_BIT);
XmSetImmediateSourceValue(P, Source);
XmSetDestinationValue(P, Operand);
P->DstLong = (UNALIGNED ULONG *)(&P->Gpr[Number].Exx);
return TRUE;
}
ULONG
XmStringOperands (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
//
// String opcode with implicit operands of eSI and eDI.
//
XmSetDataType(P);
return TRUE;
}
ULONG
XmEffectiveOffset (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
//
// Effective offset opcodes with general operand specifier.
//
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
P->ComputeOffsetAddress = TRUE;
Operand = XmEvaluateAddressSpecifier(P, &Number);
if (P->RegisterOffsetAddress != FALSE) {
longjmp(&P->JumpBuffer[0], XM_ILLEGAL_REGISTER_SPECIFIER);
}
P->SrcValue.Long = (ULONG)((ULONG_PTR)Operand);
XmTraceSource(P, P->SrcValue.Long);
P->DstLong = (ULONG UNALIGNED *)(&P->Gpr[Number].Exx);
return TRUE;
}
ULONG
XmImmediateJump (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
//
// Immediate long jump with the destination offset and new CS
// segment value. The destination of the jump is stored in the
// destination value and the new CS segment value is stored in
// destination segment.
//
if (P->OpsizePrefixActive != FALSE) {
P->DstValue.Long = XmGetLongImmediate(P);
} else {
P->DstValue.Long = XmGetWordImmediate(P);
}
P->DstSegment = XmGetWordImmediate(P);
return TRUE;
}
ULONG
XmImmediateEnter (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
enter
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
//
// Enter operands with an allocation size and level number.
//
P->SrcValue.Long = XmGetWordImmediate(P);
P->DstValue.Long = XmGetByteImmediate(P) & 0x1f;
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
return TRUE;
}
ULONG
XmGeneralBitOffset (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Offset;
ULONG Number;
//
// Bit test opcodes with a register bit offset and a memory or
// register operand.
//
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
Operand = XmEvaluateAddressSpecifier(P, &Number);
XmSetSourceValue(P, (PVOID)(&P->Gpr[Number].Exx));
if (P->RegisterOffsetAddress == FALSE) {
if (P->DataType == LONG_DATA) {
Offset = (P->SrcValue.Long >> 5) << 2;
} else {
Offset = (P->SrcValue.Long >> 4) << 1;
}
Operand = XmGetOffsetAddress(P, Offset + P->Offset);
}
if (P->DataType == LONG_DATA) {
P->SrcValue.Long &= 0x1f;
} else {
P->SrcValue.Long &= 0xf;
}
XmSetDestinationValue(P, Operand);
return TRUE;
}
ULONG
XmShiftDouble (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
shld shrd
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
ULONG Source;
//
// Shift double operators with an immediate byte or cl shift count.
//
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
Operand = XmEvaluateAddressSpecifier(P, &Number);
if ((P->CurrentOpcode & 0x1) == 0) {
Source = XmGetByteImmediate(P);
} else {
Source = P->Gpr[CX].Xl;
}
if (P->DataType == LONG_DATA) {
P->Shift = (UCHAR)(Source & 0x1f);
} else {
P->Shift = (UCHAR)(Source & 0xf);
}
XmSetSourceValue(P, (PVOID)(&P->Gpr[Number].Exx));
XmSetDestinationValue(P, Operand);
return TRUE;
}
ULONG
XmPortImmediate (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG Source;
//
// In/out opcodes with an immediate port and all other operands implied.
//
Source = (ULONG)XmGetByteImmediate(P);
P->DataType = WORD_DATA;
XmSetImmediateSourceValue(P, Source);
XmSetDataType(P);
return TRUE;
}
ULONG
XmPortDX (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG Source;
//
// In/out opcodes with a port in DX with all other operands implied.
//
Source = P->Gpr[DX].Xx;
P->DataType = WORD_DATA;
XmSetImmediateSourceValue(P, Source);
XmSetDataType(P);
return TRUE;
}
ULONG
XmBitScanGeneral (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
//
// Bit scan general opcodes with general operand specifier.
// bit.
//
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
Operand = XmEvaluateAddressSpecifier(P, &Number);
if (!Operand) return FALSE;
P->DstLong = (ULONG UNALIGNED *)(&P->Gpr[Number].Exx);
XmSetSourceValue(P, Operand);
return TRUE;
}
ULONG
XmByteImmediate (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
int xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
ULONG Source;
//
// int opcode with an immediate operand.
//
P->DataType = BYTE_DATA;
Source = XmGetImmediateSourceValue(P, 0);
XmSetImmediateSourceValue(P, Source);
return TRUE;
}
ULONG
XmXlatOpcode (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xlat
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Offset;
//
// xlat opcode with zero extended [AL] + [eBX] as the effective
// address.
//
P->DataType = BYTE_DATA;
if (P->OpaddrPrefixActive != FALSE) {
Offset = P->Gpr[EBX].Exx + P->Gpr[AL].Xl;
} else {
Offset = P->Gpr[BX].Xx + P->Gpr[AL].Xl;
}
Operand = XmGetOffsetAddress(P, Offset);
XmSetSourceValue(P, Operand);
P->DstByte = (UCHAR UNALIGNED *)(&P->Gpr[AL].Xl);
return TRUE;
}
ULONG
XmGeneralRegister (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
bswap
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
PVOID Operand;
ULONG Number;
//
// General register source and destination.
//
if (P->OpsizePrefixActive != FALSE) {
P->DataType = LONG_DATA;
} else {
P->DataType = WORD_DATA;
}
Operand = XmEvaluateAddressSpecifier(P, &Number);
if (P->RegisterOffsetAddress == FALSE) {
longjmp(&P->JumpBuffer[0], XM_ILLEGAL_GENERAL_SPECIFIER);
}
XmSetSourceValue(P, (PVOID)(&P->Gpr[Number].Exx));
P->DstLong = (ULONG UNALIGNED *)(&P->Gpr[Number].Exx);
return TRUE;
}
ULONG
XmOpcodeEscape (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
2-byte escape
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of xx is returned as the function value.
--*/
{
//
// Two byte opcode escape.
//
P->OpcodeControlTable = &XmOpcodeControlTable2[0];
#if defined(XM_DEBUG)
P->OpcodeNameTable = &XmOpcodeNameTable2[0];
#endif
return FALSE;
}
ULONG
XmPrefixOpcode (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
CS: DS; ES: SS: FS: GS: lock adrsize
opsize repz repnz
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of FALSE is returned as the function value.
--*/
{
//
// Case on the function index.
//
switch (P->FunctionIndex) {
//
// Segment override prefix.
//
// Set the segment override prefix flags and the data segment
// number.
//
case X86_ES_OP:
case X86_CS_OP:
case X86_SS_OP:
case X86_DS_OP:
case X86_FS_OP:
case X86_GS_OP:
P->SegmentPrefixActive = TRUE;
P->DataSegment = P->FunctionIndex;
XmTraceOverride(P);
break;
//
// Lock prefix.
//
// Set the lock prefix flags.
//
case X86_LOCK_OP:
P->LockPrefixActive = TRUE;
break;
//
// Address size prefix.
//
// Set the address size prefix flag.
//
case X86_ADSZ_OP:
P->OpaddrPrefixActive = TRUE;
break;
//
// Operand size prefix.
//
// Set the operand size prefix flag.
//
case X86_OPSZ_OP:
P->OpsizePrefixActive = TRUE;
break;
//
// Repeat until ECX or ZF equals zero
//
// Set up repeat until ECX or ZF equals zero prefix flags.
//
case X86_REPZ_OP:
P->RepeatPrefixActive = TRUE;
P->RepeatZflag = 1;
break;
//
// Repeat until ECX equals zero or ZF equals one.
//
// Set up repeat until ECX equals zero or ZF equals one prefix
// flags.
//
case X86_REPNZ_OP:
P->RepeatPrefixActive = TRUE;
P->RepeatZflag = 0;
break;
}
return FALSE;
}
ULONG
XmNoOperands (
IN PRXM_CONTEXT P
)
/*++
Routine Description:
This function decodes x86 operand specifiers for the following opcodes:
xxxxxx
Arguments:
P - Supplies a pointer to an emulator context structure.
Return Value:
A completion status of TRUE is returned as the function value.
--*/
{
return TRUE;
}