/* ILEngineer - Crummy .NET Decompiler
 * Copyright (C) 2001-2002  Jay Freeman (saurik)
*/

/*
 *        Redistribution and use in source and binary
 * forms, with or without modification, are permitted
 * provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the
 *    above copyright notice, this list of conditions
 *    and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the
 *    above copyright notice, this list of conditions
 *    and the following disclaimer in the documentation
 *    and/or other materials provided with the
 *    distribution.
 * 3. The name of the author may not be used to endorse
 *    or promote products derived from this software
 *    without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#include "stdafx.h"
#include "ilengineer/Block.h"

#include "ilengineer/Blocks/If.h"
#include "ilengineer/Ops/MSIL/BranchTrue.h"

void ILEngineer::Block::OptimizeIf() {
	for (StatementVector::iterator stI(m_Statements.begin()); stI != m_Statements.end(); stI++)
		if ((*stI)->isBlock())
			dynamic_cast<Block *>(*stI)->OptimizeIf();

	for (size_t i(0); i < m_Statements.size(); i++) {
		Statement *st1 = m_Statements[i];
		if (!st1->isBlock()) {
			Ops::MSIL::BranchTrue *branch = dynamic_cast<Ops::MSIL::BranchTrue *>(st1->getOperations()[0]);
			if (branch != NULL && branch->getTarget() > branch->getOffset()) {
				Blocks::If *bif = NULL;
				if (branch->getTarget() == m_End) {
					bif = new Blocks::If(m_Method, branch, st1->getOffset());
					while (i+1 < m_Statements.size()) {
						bif->getStatements().push_back(m_Statements[i+1]);
						m_Statements.erase(m_Statements.begin() + i + 1);
					}

					delete st1;
					m_Statements[i] = bif;

					bif->setEnd(m_End);
					bif->OptimizeIf();
				} else {
					Statement::Reference ref;
					Find(branch->getTarget(), ref);
					if (ref.stV == &m_Statements) {
						bif = new Blocks::If(m_Method, branch, st1->getOffset());
						while(m_Statements[i+1]->getOffset() != branch->getTarget()) {
							bif->getStatements().push_back(m_Statements[i+1]);
							m_Statements.erase(m_Statements.begin() + i + 1);
						}

						delete st1;
						m_Statements[i] = bif;

						// XXX: ACK!!!
						bif->setEnd(m_Statements[i+1]->getOffset());
						bif->OptimizeIf();
					}
				}
			}
		}
	}
}