/*
 *  PSX-Tools Bundle Pack
 *  Copyright (C) 2002-2003 Nicolas "Pixel" Noble
 * 
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

/* $Id: mipsdis.cpp,v 1.3 2004-11-27 21:44:48 pixel Exp $ */

#include "mipsdis.h"
#include "mips.h"

TDis::TDis(mipsmem * _m) : mm(_m) {
    reset();
}

void TDis::reset() {
    invalid = false;
}

mipsmem * TDis::getmem() {
    return mm;
}

void TDis::add_branch(Uint32 target) {
    bheap.push(target);
}

void TDis::add_jump(Uint32 target) {
    jheap.push(target);
}

void TDis::add_function(Uint32 target) {
    fheap.push(target);
}

void TDis::SetTag(Uint32 target, int tag, bool v) {
    mm->SetTag(target, tag, v);
}

void TDis::Name(const String & name) {
}

void TDis::PushGPReg(int reg) {
}

void TDis::PushCPReg(int reg) {
}

void TDis::PushImm(Uint32 imm) {
}

void TDis::PushTarget(Uint32 target) {
    new refto_t(target, memdata::getmem(pc, getmem()));
}

void TDis::PushSa(Uint32 sa) {
}

void TDis::PushOfB(int reg, Uint32 offset, int width) {
}

void TDis::PushOffset(Uint32 offset) {
    new refto_t(offset, memdata::getmem(pc, getmem()));
}

void TDis::PushFull(Uint32 full) {
    if ((full >= 0x80000000) && (full < (0x80000000 + PSXMEM)))
	new refto_t(full, memdata::getmem(pc, getmem()));
}

void TDis::Invalid() {
    invalid = true;
}

void TDis::Suspect() {
}

void TDis::Comment(const String & c) {
}

Disassembler::Disassembler(mipsmem * _mm) : mm(_mm), dis(new TDis(mm)), started(false), infunction(false) {
}

Disassembler::~Disassembler() {
    delete dis;
}

void Disassembler::crawl_code(Uint32 pc) {
    Uint32 branched, ipc;
    
    if (pc == 0xffffffff) {
	pc = mm->GetPC();
    }
    
    dis->bheap.push(pc);
    
    while (dis->bheap.size()) {
	branched = pc = dis->bheap.top();
	dis->bheap.pop();
	printm(M_STATUS, "Crawling to branch %8.8lX\n", pc);
	do {
	    if (pc >= (0x80000000 + PSXMEM)) {
		dis->invalid = true;
		break;
	    }
	    if (mm->GetTag(pc, CODE) || mm->GetTag(pc, INVALID)) {
		pc += 4;
		continue;
	    }
	    mm->SetTag(pc, CODE, true);
	    
	    printm(M_STATUS, "Working at %8.8lX\n", pc);
	    decode(dis, pc);
	    
	    pc += 4;
	    dis->reset();
	} while (!mm->GetTag(pc, STOP) && !dis->invalid);
	
	if (dis->invalid) {
	    for (ipc = branched; ipc <= pc; ipc += 4) {
		mm->SetTag(ipc, CODE, false);
		mm->SetTag(ipc, INVALID, true);
	    }
	}
	
	if (dis->invalid && infunction) {
	}
    }
}

void Disassembler::mainloop(void) {
    Uint32 pc;
    
    infunction = false;

    // Crawl the start part.
    printm(M_STATUS, "Starting crawl at %8.8lX\n", mm->GetPC());
    if (!started)
	crawl_code();
    
    started = true;
    
    // Work out all the functions.
    printm(M_STATUS, "Crawling all detected functions\n");
    infunction = true;
    while (dis->fheap.size()) {
	pc = dis->fheap.top();
	dis->fheap.pop();
	printm(M_STATUS, "Crawling function %8.8lX\n", pc);
	if (mm->GetTag(pc, CODE))
	    continue;
	crawl_code(pc);
    }

    // Complete functions and all the detected jumps.
    printm(M_STATUS, "Fixing all the remaining jumps\n");
#if 0
    infunction = false;
    while (dis->jheap.size()) {
	pc = dis->jheap.top();
	dis->jheap.pop();
	if (mm->GetTag(pc, CODE))
	    continue;
	crawl_code(pc);
    }
#endif
}