// Disassembles one command from the heap, returns address of next command or 0 if a ret was encountered.
reg_t disassemble(EngineState *s, reg32_t pos, reg_t objAddr, bool printBWTag, bool printBytecode) {
SegmentObj *mobj = s->_segMan->getSegment(pos.getSegment(), SEG_TYPE_SCRIPT);
Script *script_entity = NULL;
reg_t retval;
retval.setSegment(pos.getSegment());
retval.setOffset(pos.getOffset() + 1);
uint16 param_value = 0xffff; // Suppress GCC warning by setting default value, chose value as invalid to getKernelName etc.
uint i = 0;
Kernel *kernel = g_sci->getKernel();
if (!mobj) {
warning("Disassembly failed: Segment %04x non-existent or not a script", pos.getSegment());
return retval;
} else
script_entity = (Script *)mobj;
uint scr_size = script_entity->getBufSize();
if (pos.getOffset() >= scr_size) {
warning("Trying to disassemble beyond end of script");
return NULL_REG;
}
const byte *scr = script_entity->getBuf();
int16 opparams[4];
byte opsize;
uint bytecount = readPMachineInstruction(scr + pos.getOffset(), opsize, opparams);
const byte opcode = opsize >> 1;
debugN("%04x:%04x: ", PRINT_REG(pos));
if (printBytecode) {
if (pos.getOffset() + bytecount > scr_size) {
warning("Operation arguments extend beyond end of script");
return retval;
}
for (i = 0; i < bytecount; i++)
debugN("%02x ", scr[pos.getOffset() + i]);
for (i = bytecount; i < 5; i++)
debugN(" ");
}
opsize &= 1; // byte if true, word if false
if (printBWTag)
debugN("[%c] ", opsize ? 'B' : 'W');
if (opcode == op_pushSelf && opsize && g_sci->getGameId() != GID_FANMADE) { // 0x3e (62)
// Debug opcode op_file
debugN("file \"%s\"\n", scr + pos.getOffset() + 1); // +1: op_pushSelf size
retval.incOffset(bytecount - 1);
return retval;
}
#ifndef REDUCE_MEMORY_USAGE
debugN("%-5s", opcodeNames[opcode]);
#endif
static const char *defaultSeparator = "\t\t; ";
i = 0;
while (g_sci->_opcode_formats[opcode][i]) {
switch (g_sci->_opcode_formats[opcode][i++]) {
case Script_Invalid:
warning("-Invalid operation-");
break;
case Script_SByte:
case Script_Byte:
param_value = scr[retval.getOffset()];
debugN("\t%02x", param_value);
if (param_value > 9) {
debugN("%s%u", defaultSeparator, param_value);
}
retval.incOffset(1);
break;
case Script_Word:
case Script_SWord:
param_value = READ_SCI11ENDIAN_UINT16(&scr[retval.getOffset()]);
debugN("\t%04x", param_value);
if (param_value > 9) {
debugN("%s%u", defaultSeparator, param_value);
}
retval.incOffset(2);
break;
case Script_SVariable:
case Script_Variable:
case Script_Property:
case Script_Global:
case Script_Local:
case Script_Temp:
case Script_Param:
if (opsize) {
param_value = scr[retval.getOffset()];
retval.incOffset(1);
} else {
param_value = READ_SCI11ENDIAN_UINT16(&scr[retval.getOffset()]);
retval.incOffset(2);
}
if (opcode == op_callk) {
debugN("\t%s[%x],", (param_value < kernel->_kernelFuncs.size()) ?
((param_value < kernel->getKernelNamesSize()) ? kernel->getKernelName(param_value).c_str() : "[Unknown(postulated)]")
: "<invalid>", param_value);
} else if (opcode == op_class) {
const reg_t classAddr = s->_segMan->getClassAddress(param_value, SCRIPT_GET_DONT_LOAD, retval.getSegment());
if (!classAddr.isNull()) {
debugN("\t%s", s->_segMan->getObjectName(classAddr));
debugN(opsize ? "[%02x]" : "[%04x]", param_value);
} else {
debugN(opsize ? "\t%02x" : "\t%04x", param_value);
}
} else if (opcode == op_super) {
Object *obj;
if (objAddr != NULL_REG && (obj = s->_segMan->getObject(objAddr)) != nullptr) {
debugN("\t%s", s->_segMan->getObjectName(obj->getSuperClassSelector()));
debugN(opsize ? "[%02x]" : "[%04x]", param_value);
} else {
debugN(opsize ? "\t%02x" : "\t%04x", param_value);
}
debugN(",");
#ifdef ENABLE_SCI32
} else if (getSciVersion() == SCI_VERSION_3 && (
opcode == op_pToa || opcode == op_aTop ||
opcode == op_pTos || opcode == op_sTop ||
opcode == op_ipToa || opcode == op_dpToa ||
opcode == op_ipTos || opcode == op_dpTos)) {
const char *selectorName = "<invalid>";
if (param_value < kernel->getSelectorNamesSize()) {
selectorName = kernel->getSelectorName(param_value).c_str();
}
debugN("\t%s[%x]", selectorName, param_value);
#endif
} else {
const char *separator = defaultSeparator;
debugN(opsize ? "\t%02x" : "\t%04x", param_value);
if (param_value > 9) {
debugN("%s%u", separator, param_value);
separator = ", ";
}
if (param_value >= 0x20 && param_value <= 0x7e) {
debugN("%s'%c'", separator, param_value);
separator = ", ";
}
if (opcode == op_pushi && param_value < kernel->getSelectorNamesSize()) {
debugN("%s%s", separator, kernel->getSelectorName(param_value).c_str());
}
}
break;
case Script_Offset: {
assert(opcode == op_lofsa || opcode == op_lofss);
if (opsize) {
param_value = scr[retval.getOffset()];
retval.incOffset(1);
} else {
param_value = READ_SCI11ENDIAN_UINT16(&scr[retval.getOffset()]);
retval.incOffset(2);
}
const uint32 offset = findOffset(param_value, script_entity, retval.getOffset());
reg_t addr;
addr.setSegment(retval.getSegment());
addr.setOffset(offset);
debugN("\t%s", s->_segMan->getObjectName(addr));
debugN(opsize ? "[%02x]" : "[%04x]", offset);
break;
}
case Script_SRelative:
if (opsize) {
int8 offset = (int8)scr[retval.getOffset()];
retval.incOffset(1);
debugN("\t%02x [%04x]", 0xff & offset, kOffsetMask & (retval.getOffset() + offset));
} else {
int16 offset = (int16)READ_SCI11ENDIAN_UINT16(&scr[retval.getOffset()]);
retval.incOffset(2);
debugN("\t%04x [%04x]", 0xffff & offset, kOffsetMask & (retval.getOffset() + offset));
}
break;
case Script_End:
retval = NULL_REG;
break;
default:
error("Internal assertion failed in disassemble()");
}
}
if (pos == s->xs->addr.pc) { // Extra information if debugging the current opcode
if ((opcode == op_pTos) || (opcode == op_sTop) || (opcode == op_pToa) || (opcode == op_aTop) ||
(opcode == op_dpToa) || (opcode == op_ipToa) || (opcode == op_dpTos) || (opcode == op_ipTos)) {
const Object *obj = s->_segMan->getObject(s->xs->objp);
if (!obj) {
warning("Attempted to reference on non-object at %04x:%04x", PRINT_REG(s->xs->objp));
} else {
if (getSciVersion() == SCI_VERSION_3)
debugN("\t(%s)", g_sci->getKernel()->getSelectorName(param_value).c_str());
else
debugN("\t(%s)", g_sci->getKernel()->getSelectorName(obj->propertyOffsetToId(s->_segMan, param_value)).c_str());
}
}
}
debugN("\n");
if (pos == s->xs->addr.pc) { // Extra information if debugging the current opcode
if (opcode == op_callk) {
int stackframe = (scr[pos.getOffset() + 2] >> 1) + (s->r_rest);
int argc = ((s->xs->sp)[- stackframe - 1]).getOffset();
bool oldScriptHeader = (getSciVersion() == SCI_VERSION_0_EARLY);
if (!oldScriptHeader)
argc += (s->r_rest);
debugN(" Kernel params: (");
for (int j = 0; j < argc; j++) {
debugN("%04x:%04x", PRINT_REG((s->xs->sp)[j - stackframe]));
if (j + 1 < argc)
debugN(", ");
}
debugN(")\n");
} else if ((opcode == op_send) || (opcode == op_self)) {
