private void writeIf(IfBlock block)
{
string cond;
if (block.logic == null)
{
writeStatements(block.source);
DJumpCondition jcc = (DJumpCondition)block.source.nodes.last;
if (block.invert)
{
if (jcc.getOperand(0).type == NodeType.Unary &&
((DUnary)jcc.getOperand(0)).spop == SPOpcode.not)
{
cond = buildExpression(jcc.getOperand(0).getOperand(0));
}
else if (jcc.getOperand(0).type == NodeType.Load)
{
cond = "!" + buildExpression(jcc.getOperand(0));
}
else
{
cond = "!(" + buildExpression(jcc.getOperand(0)) + ")";
}
}
else
{
cond = buildExpression(jcc.getOperand(0));
}
}
else
{
cond = buildLogicChain(block.logic);
Debug.Assert(!block.invert);
}
outputLine("if (" + cond + ")");
outputLine("{");
increaseIndent();
writeBlock(block.trueArm);
decreaseIndent();
if (block.falseArm != null &&
BlockAnalysis.GetEmptyTarget(block.falseArm.source) == null)
{
outputLine("}");
outputLine("else");
outputLine("{");
increaseIndent();
writeBlock(block.falseArm);
decreaseIndent();
}
outputLine("}");
if (block.join != null)
{
writeBlock(block.join);
}
}
private ControlType findLoopJoinAndBody(NodeBlock header, NodeBlock effectiveHeader,
out NodeBlock join, out NodeBlock body, out NodeBlock cond)
{
//Debug.Assert(effectiveHeader.lir.numSuccessors == 2);
LBlock succ1 = effectiveHeader.lir.getSuccessor(0);
LBlock succ2 = effectiveHeader.lir.getSuccessor(1);
if (succ1.loop != header.lir || succ2.loop != header.lir)
{
//Debug.Assert(succ1.loop == header.lir || succ2.loop == header.lir);
if (succ1.loop != header.lir)
{
join = graph_[succ1.id];
body = graph_[succ2.id];
}
else
{
join = graph_[succ2.id];
body = graph_[succ1.id];
}
cond = header;
// If this is a self-loop, it is more correct to decompose it
// to a do-while loop. This may not be source accurate in the
// case of something like |while (x);| but it catches many more
// source-accurate cases.
if (header == effectiveHeader &&
BlockAnalysis.GetEmptyTarget(body) == header)
{
body = null;
return(ControlType.DoWhileLoop);
}
return(ControlType.WhileLoop);
}
else
{
// Neither successor of the header exits the loop, so this is
// probably a do-while loop. For now, assume it's simple.
//Debug.Assert(header == effectiveHeader);
LBlock backedge = header.lir.backedge;
if (BlockAnalysis.GetEmptyTarget(graph_[backedge.id]) == header)
{
// Skip an empty block sitting in between the backedge and
// the condition.
//Debug.Assert(backedge.numPredecessors == 1);
backedge = backedge.getPredecessor(0);
}
//Debug.Assert(backedge.numSuccessors == 2);
succ1 = backedge.getSuccessor(0);
succ2 = backedge.getSuccessor(1);
body = header;
cond = graph_[backedge.id];
if (succ1.loop != header.lir)
{
join = graph_[succ1.id];
}
else
{
//Debug.Assert(succ2.loop != header.lir);
join = graph_[succ2.id];
}
return(ControlType.DoWhileLoop);
}
}