private ForStatementDownNode Visit(ForStatementDownNode node)
{
Visit(node.expr1);
builder.BuildStore(GetProperty(node.expr1).addr, LookupSymbolOrAlloc(node.Identifier));
var condBB = func.AppendBasicBlock($"cond_{++count}");
var bodyBB = func.AppendBasicBlock($"body_{++count}");
var contBB = func.AppendBasicBlock($"cont_{++count}");
builder.BuildBr(condBB);
builder.PositionAtEnd(condBB);
Visit(node.expr2);
var t = builder.BuildLoad(LookupSymbolOrAlloc(node.Identifier));
var b = builder.BuildICmp(LLVMIntPredicate.LLVMIntSGE, t, GetProperty(node.expr2).addr);
builder.BuildCondBr(b, bodyBB, contBB);
builder.PositionAtEnd(bodyBB);
Visit(node.StatementNode);
t = builder.BuildLoad(LookupSymbolOrAlloc(node.Identifier));
var r = builder.BuildSub(t, LLVMValueRef.CreateConstInt(LLVMTypeRef.Int32, 1));
builder.BuildStore(r, LookupSymbolOrAlloc(node.Identifier));
builder.BuildBr(condBB);
builder.PositionAtEnd(contBB);
return(node);
}
private ForStatementDownNode Visit(ForStatementDownNode node)
{
var beginLabel = MakeLabel();
var trueLabel = MakeLabel();
var nextLabel = MakeLabel();
node.expr1.Visit(this);
generatedCode.Add(new CodeEntity()
{
Code = $"{node.Identifier} = {properties[node.expr1].addr}"
});
generatedCode.Add(beginLabel);
node.expr2.Visit(this);
generatedCode.Add(new CodeEntity()
{
Code = $"if {node.Identifier} >= {properties[node.expr2].addr} goto <label:{trueLabel.LabelId}>"
});
generatedCode.Add(MakeLabeledGoto(nextLabel));
generatedCode.Add(trueLabel);
node.StatementNode.Visit(this);
var temp = MakeTemp();
generatedCode.Add(new CodeEntity()
{
Code = $"{temp} = {node.Identifier} - 1"
});
generatedCode.Add(new CodeEntity()
{
Code = $"{node.Identifier} = {temp}"
});
generatedCode.Add(MakeLabeledGoto(beginLabel));
generatedCode.Add(nextLabel);
return(node);
}
private ForStatementDownNode Visit(ForStatementDownNode node)
{
dynamic props = new ExpandoObject();
properties.Add(node, props);
var code = new List <CodeEntry>();
props.code = code;
var beginLabel = MakeLabel();
var trueLabel = MakeLabel();
var nextLabel = MakeLabel();
var temp = MakeTemp();
code.AddRange(properties[node.expr1].code);
code.Add(new CodeEntity()
{
Code = $"{node.Identifier} = {properties[node.expr1].addr}"
});
code.Add(beginLabel);
code.AddRange(properties[node.expr2].code);
code.Add(new CodeEntity()
{
Code = $"if {node.Identifier} >= {properties[node.expr2].addr} goto <label:{trueLabel.LabelId}>"
});
code.Add(MakeLabeledGoto(nextLabel));
code.Add(trueLabel);
code.AddRange(properties[node.StatementNode].code);
code.Add(new CodeEntity()
{
Code = $"{temp} = {node.Identifier} - 1"
});
code.Add(new CodeEntity()
{
Code = $"{node.Identifier} = {temp}"
});
code.Add(MakeLabeledGoto(beginLabel));
code.Add(nextLabel);
return(node);
}
