DISASM.C
/*++
Copyright (c) 1993 Microsoft Corporation
Module Name:
regs.c
Abstract:
This file provides disassembly ( alpha )
Author:
Miche Baker-Harvey (v-michbh) 1-May-1993 (ported from ntsd)
Environment:
User Mode
--*/
#include <windows.h>
#include <stddef.h>
#include <string.h>
#include <stdio.h>
#include <alphaops.h>
#include "disasm.h"
#include "regs.h"
#include "optable.h"
#include "drwatson.h"
#include "proto.h"
void BlankFill(ULONG);
void OutputHex(ULONG, ULONG, BOOLEAN);
void OutputEffectiveAddress(PDEBUGPACKET, ULONG);
void OutputString(char *);
void OutputReg(ULONG);
void OutputFReg(ULONG);
void GetNextOffset(PDEBUGPACKET, PULONG, BOOLEAN);
ULONG GetIntRegNumber(ULONG);
ALPHA_INSTRUCTION disinstr;
extern PUCHAR pszReg[];
BOOLEAN disasm(PDEBUGPACKET, PDWORD, PUCHAR, BOOLEAN);
static char *pBufStart;
static char *pBuf;
#define OPRNDCOL 27 // Column for first operand
#define EACOL 40 // column for effective address
#define FPTYPECOL 40 // .. for the type of FP instruction
BOOLEAN
disasm (PDEBUGPACKET dp, PDWORD poffset, PUCHAR bufptr, BOOLEAN fEAout)
{
static initialized = 0;
ULONG opcode;
ULONG Ea; // Effective Address
POPTBLENTRY pEntry;
if (!initialized) {
opTableInit();
initialized = 1;
}
pBufStart = pBuf = bufptr; // Initialize pointers to buffer that
// will receive the disassembly text
OutputHex(*poffset, 8, FALSE);// Output Hex address of instruction
*pBuf++ = ':';
*pBuf++ = ' ';
if (!DoMemoryRead( dp,
(LPVOID)*poffset,
(LPVOID)&disinstr.Long,
sizeof(DWORD),
NULL
)) {
OutputString("???????? ????");
*pBuf = '\0';
return(FALSE);
}
OutputHex(disinstr.Long, 8, FALSE); // Output instruction in Hex
*pBuf++ = ' ';
opcode = disinstr.Memory.Opcode; // Select disassembly procedure from
pEntry = findOpCodeEntry(opcode); // Get non-func entry for this code
if (pEntry == (POPTBLENTRY)-1) {
OutputString("??????? ????");
*pBuf = '\0';
return (FALSE);
}
switch (pEntry->iType) {
case ALPHA_UNKNOWN:
OutputString(pEntry->pszAlphaName);
break;
case ALPHA_MEMORY:
OutputString(pEntry->pszAlphaName);
BlankFill(OPRNDCOL);
OutputReg(disinstr.Memory.Ra);
*pBuf++ = ',';
OutputHex(disinstr.Memory.MemDisp, (WIDTH_MEM_DISP + 3)/4, TRUE );
*pBuf++ = '(';
OutputReg(disinstr.Memory.Rb);
*pBuf++ = ')';
break;
case ALPHA_FP_MEMORY:
OutputString(pEntry->pszAlphaName);
BlankFill(OPRNDCOL);
OutputFReg(disinstr.Memory.Ra);
*pBuf++ = ',';
OutputHex(disinstr.Memory.MemDisp, (WIDTH_MEM_DISP + 3)/4, TRUE );
*pBuf++ = '(';
OutputReg(disinstr.Memory.Rb);
*pBuf++ = ')';
break;
case ALPHA_MEMSPC:
OutputString(findFuncName(pEntry, disinstr.Memory.MemDisp & BITS_MEM_DISP));
//
// Some memory special instructions have an operand
//
switch (disinstr.Memory.MemDisp & BITS_MEM_DISP) {
case FETCH_FUNC:
case FETCH_M_FUNC:
// one operand, in Rb
BlankFill(OPRNDCOL);
*pBuf++ = '0';
*pBuf++ = '(';
OutputReg(disinstr.Memory.Rb);
*pBuf++ = ')';
break;
case RS_FUNC:
case RC_FUNC:
case RPCC_FUNC:
// one operand, in Ra
BlankFill(OPRNDCOL);
OutputReg(disinstr.Memory.Ra);
break;
case MB_FUNC:
case WMB_FUNC:
case MB2_FUNC:
case MB3_FUNC:
case TRAPB_FUNC:
case EXCB_FUNC:
// no operands
break;
default:
printf("we shouldn't get here \n");
break;
}
break;
case ALPHA_JUMP:
OutputString(findFuncName(pEntry, disinstr.Jump.Function));
BlankFill(OPRNDCOL);
OutputReg(disinstr.Jump.Ra);
*pBuf++ = ',';
*pBuf++ = '(';
OutputReg(disinstr.Jump.Rb);
*pBuf++ = ')';
*pBuf++ = ',';
OutputHex(disinstr.Jump.Hint, (WIDTH_HINT + 3)/4, TRUE);
Ea = (ULONG) GetRegValue(dp, GetIntRegNumber(disinstr.Jump.Rb)) & (~3);
OutputEffectiveAddress(dp, Ea);
break;
case ALPHA_BRANCH:
OutputString(pEntry->pszAlphaName);
BlankFill(OPRNDCOL);
OutputReg(disinstr.Branch.Ra);
*pBuf++ = ',';
//
// The next line might be a call to GetNextOffset, but
// GetNextOffset assumes that it should work from REGFIR.
//
Ea = *poffset +
sizeof(DWORD) +
(disinstr.Branch.BranchDisp << 2);
OutputHex(Ea, 8, FALSE);
OutputEffectiveAddress(dp, Ea);
break;
case ALPHA_FP_BRANCH:
OutputString(pEntry->pszAlphaName);
BlankFill(OPRNDCOL);
OutputFReg(disinstr.Branch.Ra);
*pBuf++ = ',';
//
// The next line might be a call to GetNextOffset, but
// GetNextOffset assumes that it should work from REGFIR.
//
Ea = *poffset +
sizeof(DWORD) +
(disinstr.Branch.BranchDisp << 2);
OutputHex(Ea, 8, FALSE);
OutputEffectiveAddress(dp, Ea);
break;
case ALPHA_OPERATE:
OutputString(findFuncName(pEntry, disinstr.OpReg.Function));
BlankFill(OPRNDCOL);
OutputReg(disinstr.OpReg.Ra);
*pBuf++ = ',';
if (disinstr.OpReg.RbvType) {
*pBuf++ = '#';
OutputHex(disinstr.OpLit.Literal, (WIDTH_LIT + 3)/4, TRUE);
} else
OutputReg(disinstr.OpReg.Rb);
*pBuf++ = ',';
OutputReg(disinstr.OpReg.Rc);
break;
case ALPHA_FP_OPERATE:
{
ULONG Function;
ULONG Flags;
Flags = disinstr.FpOp.Function & MSK_FP_FLAGS;
Function = disinstr.FpOp.Function & MSK_FP_OP;
// if (fVerboseOutput) {
// dprintf("In FP_OPERATE: Flags %08x Function %08x\n",
// Flags, Function);
// dprintf("opcode %d \n", opcode);
// }
//
// CVTST and CVTST/S are different: they look like
// CVTTS with some flags set
//
if (Function == CVTTS_FUNC) {
if (disinstr.FpOp.Function == CVTST_S_FUNC) {
Function = CVTST_S_FUNC;
Flags = NONE_FLAGS;
}
if (disinstr.FpOp.Function == CVTST_FUNC) {
Function = CVTST_FUNC;
Flags = NONE_FLAGS;
}
}
OutputString(findFuncName(pEntry, Function));
//
// Append the opcode qualifier, if any, to the opcode name.
//
if ( (opcode == IEEEFP_OP) || (opcode == VAXFP_OP)
|| (Function == CVTQL_FUNC) ) {
OutputString(findFlagName(Flags, Function));
}
BlankFill(OPRNDCOL);
//
// If this is a convert instruction, only Rb and Rc are used
//
if (strncmp("cvt", findFuncName(pEntry, Function), 3) != 0) {
OutputFReg(disinstr.FpOp.Fa);
*pBuf++ = ',';
}
OutputFReg(disinstr.FpOp.Fb);
*pBuf++ = ',';
OutputFReg(disinstr.FpOp.Fc);
break;
}
case ALPHA_FP_CONVERT:
OutputString(pEntry->pszAlphaName);
BlankFill(OPRNDCOL);
OutputFReg(disinstr.FpOp.Fa);
*pBuf++ = ',';
OutputFReg(disinstr.FpOp.Fb);
break;
case ALPHA_CALLPAL:
OutputString(findFuncName(pEntry, disinstr.Pal.Function));
break;
case ALPHA_EV4_PR:
if ((disinstr.Long & MSK_EV4_PR) == 0)
OutputString("NOP");
else {
OutputString(pEntry->pszAlphaName);
BlankFill(OPRNDCOL);
OutputReg(disinstr.EV4_PR.Ra);
*pBuf++ = ',';
if(disinstr.EV4_PR.Ra != disinstr.EV4_PR.Rb) {
OutputReg(disinstr.EV4_PR.Rb);
*pBuf++ = ',';
};
OutputString(findFuncName(pEntry, (disinstr.Long & MSK_EV4_PR)));
};
break;
case ALPHA_EV4_MEM:
OutputString(pEntry->pszAlphaName);
BlankFill(OPRNDCOL);
OutputReg(disinstr.EV4_MEM.Ra);
*pBuf++ = ',';
OutputReg(disinstr.EV4_MEM.Rb);
break;
case ALPHA_EV4_REI:
OutputString(pEntry->pszAlphaName);
break;
default:
OutputString("Invalid type");
break;
};
*poffset += sizeof(ULONG);
*pBuf = '\0';
return(TRUE);
}
/* BlankFill - blank-fill buffer
*
* Purpose:
* To fill the buffer at *pBuf with blanks until
* position count is reached.
*
* Input:
* None.
*
* Output:
* None.
*
***********************************************************************/
void BlankFill(ULONG count)
{
do
*pBuf++ = ' ';
while (pBuf < pBufStart + count);
}
/* OutputHex - output hex value
*
* Purpose:
* Output the value in outvalue into the buffer
* pointed by *pBuf. The value may be signed
* or unsigned depending on the value fSigned.
*
* Input:
* outvalue - value to output
* length - length in digits
* fSigned - TRUE if signed else FALSE
*
* Output:
* None.
*
***********************************************************************/
UCHAR HexDigit[16] = {
'0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
};
void OutputHex (ULONG outvalue, ULONG length, BOOLEAN fSigned)
{
UCHAR digit[8];
LONG index = 0;
if (fSigned && (LONG)outvalue < 0) {
*pBuf++ = '-';
outvalue = - (LONG)outvalue;
}
do {
digit[index++] = HexDigit[outvalue & 0xf];
outvalue >>= 4;
}
while ((fSigned && outvalue) || (!fSigned && index < (LONG)length))
;
while (--index >= 0)
*pBuf++ = digit[index];
}
/* OutputString - output string
*
* Purpose:
* Copy the string into the buffer pointed by pBuf.
*
* Input:
* *pStr - pointer to string
*
* Output:
* None.
*
***********************************************************************/
void OutputString (char *pStr)
{
while (*pStr)
*pBuf++ = *pStr++;
}
void OutputReg (ULONG regnum)
{
OutputString(pszReg[GetIntRegNumber(regnum)]);
}
void OutputFReg (ULONG regnum)
{
*pBuf++ = 'f';
if (regnum > 9)
*pBuf++ = (UCHAR)('0' + regnum / 10);
*pBuf++ = (UCHAR)('0' + regnum % 10);
}
/*** OutputEffectiveAddress - Print EA symbolically
*
* Purpose:
* Given the effective address (for a branch, jump or
* memory instruction, print it symbolically, if
* symbols are available.
*
* Input:
* offset - computed by the caller as
* for jumps, the value in Rb
* for branches, func(PC, displacement)
* for memory, func(PC, displacement)
*
* Returns:
* None
*
*************************************************************************/
void OutputEffectiveAddress(PDEBUGPACKET dp, ULONG offset)
{
ULONG displacement;
PUCHAR pszTemp;
UCHAR ch;
BlankFill(EACOL);
if (SymGetSymFromAddr( dp->hProcess, offset, &displacement, sym )) {
pszTemp = sym->Name;
while (ch = *pszTemp++)
*pBuf++ = ch;
if (displacement) {
*pBuf++ = '+';
OutputHex(displacement, 8, TRUE);
}
}
else {
OutputHex(offset, 8, FALSE);
}
}
/*** GetNextOffset - compute offset for trace or step
*
* Purpose:
* From a limited disassembly of the instruction pointed
* by the FIR register, compute the offset of the next
* instruction for either a trace or step operation.
*
* trace -> the next instruction to execute
* step -> the instruction in the next memory location or the
* next instruction executed due to a branch (step over
* subroutine calls).
*
* Input:
* result - where to put the next offset
* fStep - TRUE for step offset; FALSE for trace offset
*
* Returns:
* step or trace offset if input is TRUE or FALSE, respectively
* in result
*
*************************************************************************/
/*
void
GetNextOffset (PDEBUGPACKET dp, PULONG result, BOOLEAN fStep)
{
ULONG rv;
ULONG opcode;
ULONG firaddr;
ULONG updatedpc;
ULONG branchTarget;
DWORD fir;
// Canonical form to shorten tests; Abs is absolute value
LONG Can, Abs;
CONVERTED_DOUBLE Rav;
CONVERTED_DOUBLE Fav;
CONVERTED_DOUBLE Rbv;
//
// Get current address
//
firaddr = (ULONG) GetRegValue(dp, REGFIR);
//
// relative addressing updates PC first
// Assume next sequential instruction is next offset
//
updatedpc = firaddr + sizeof(ULONG);
rv = updatedpc;
DoMemoryRead( dp,
(LPVOID)firaddr,
(LPVOID)&disinstr.Long,
sizeof(ULONG),
NULL
);
opcode = disinstr.Memory.Opcode;
switch(findOpCodeEntry(opcode)->iType) {
case ALPHA_JUMP:
switch(disinstr.Jump.Function) {
case JSR_FUNC:
case JSR_CO_FUNC:
if (fStep) {
//
// Step over the subroutine call;
//
break;
}
//
// fall through
//
case JMP_FUNC:
case RET_FUNC:
GetQuadRegValue(dp, GetIntRegNumber(disinstr.Jump.Rb), &Rbv);
rv = (Rbv.li.LowPart & (~3));
break;
}
break;
case ALPHA_BRANCH:
branchTarget = (updatedpc + (disinstr.Branch.BranchDisp * 4));
GetQuadRegValue(dp, GetIntRegNumber(disinstr.Branch.Ra), &Rav.li);
//
// set up a canonical value for computing the branch test
// - works with ALPHA, MIPS and 386 hosts
//
Can = Rav.li.LowPart & 1;
if ((LONG)Rav.li.HighPart < 0) {
Can |= 0x80000000;
}
if ((Rav.li.LowPart & 0xfffffffe) || (Rav.li.HighPart & 0x7fffffff)) {
Can |= 2;
}
// if (fVerboseOutput) {
// dprintf("Rav High %08lx Low %08lx Canonical %08lx\n",
// Rav.li.HighPart, Rav.li.LowPart, Can);
// dprintf("returnvalue %08lx branchTarget %08lx\n",
// rv, branchTarget);
// }
switch(opcode) {
case BR_OP: rv = branchTarget; break;
case BSR_OP: if (!fStep) rv = branchTarget; break;
case BEQ_OP: if (Can == 0) rv = branchTarget; break;
case BLT_OP: if (Can < 0) rv = branchTarget; break;
case BLE_OP: if (Can <= 0) rv = branchTarget; break;
case BNE_OP: if (Can != 0) rv = branchTarget; break;
case BGE_OP: if (Can >= 0) rv = branchTarget; break;
case BGT_OP: if (Can > 0) rv = branchTarget; break;
case BLBC_OP: if ((Can & 0x1) == 0) rv = branchTarget; break;
case BLBS_OP: if ((Can & 0x1) == 1) rv = branchTarget; break;
};
break;
case ALPHA_FP_BRANCH:
branchTarget = (updatedpc + (disinstr.Branch.BranchDisp * 4));
GetFloatingPointRegValue(dp, disinstr.Branch.Ra, &Fav);
//
// Set up a canonical value for computing the branch test
//
Can = Fav.li.HighPart & 0x80000000;
//
// The absolute value is needed -0 and non-zero computation
//
Abs = Fav.li.LowPart || (Fav.li.HighPart & 0x7fffffff);
if (Can && (Abs == 0x0)) {
//
// negative 0 should be considered as zero
//
Can = 0x0;
} else {
Can |= Abs;
}
// if (fVerboseOutput) {
// dprintf("Fav High %08lx Low %08lx Canonical %08lx Absolute %08lx\n",
// Fav.li.HighPart, Fav.li.LowPart, Can, Abs);
// dprintf("returnvalue %08lx branchTarget %08lx\n",
// rv, branchTarget);
// }
switch(opcode) {
case FBEQ_OP: if (Can == 0) rv = branchTarget; break;
case FBLT_OP: if (Can < 0) rv = branchTarget; break;
case FBNE_OP: if (Can != 0) rv = branchTarget; break;
case FBLE_OP: if (Can <= 0) rv = branchTarget; break;
case FBGE_OP: if (Can >= 0) rv = branchTarget; break;
case FBGT_OP: if (Can > 0) rv = branchTarget; break;
};
break;
};
// if (fVerboseOutput) {
// dprintf("GetNextOffset returning %08lx\n", rv);
// }
*result = rv;
}
*/