/// <include file='Doc/Nodes.xml' path='doc/method[@name="Emit"]/*'/>
internal override void Emit(CodeGenerator codeGenerator)
{
Statistics.AST.AddNode("Loop.While");
ILEmitter il = codeGenerator.IL;
Label cond_label = il.DefineLabel();
Label exit_label = il.DefineLabel();
Label stat_label = il.DefineLabel();
codeGenerator.BranchingStack.BeginLoop(cond_label, exit_label, codeGenerator.ExceptionBlockNestingLevel);
if (this.type == Type.While)
{
il.Emit(OpCodes.Br, cond_label);
}
// body:
il.MarkLabel(stat_label);
body.Emit(codeGenerator);
// marks a sequence point containing condition:
codeGenerator.MarkSequencePoint(
condExpr.Position.FirstLine,
condExpr.Position.FirstColumn,
condExpr.Position.LastLine,
condExpr.Position.LastColumn + 1);
// condition:
il.MarkLabel(cond_label);
// bounded loop:
if (condExpr != null)
{
// IF (<(bool) condition>) GOTO stat;
codeGenerator.EmitConversion(condExpr, PhpTypeCode.Boolean);
il.Emit(OpCodes.Brtrue, stat_label);
}
il.MarkLabel(exit_label);
codeGenerator.BranchingStack.EndLoop();
il.ForgetLabel(cond_label);
il.ForgetLabel(exit_label);
il.ForgetLabel(stat_label);
}
/// <include file='Doc/Nodes.xml' path='doc/method[@name="Emit"]/*'/>
internal override void Emit(CodeGenerator codeGenerator)
{
Statistics.AST.AddNode("IfStmt");
Debug.Assert(conditions.Count > 0);
// marks a sequence point containing whole condition:
codeGenerator.MarkSequencePoint(conditions[0].Condition); // NOTE: (J) when emitting a statement, sequence point has to be marked. Normally it is done in Statement.Emit()
ILEmitter il = codeGenerator.IL;
Label exit_label = il.DefineLabel();
Label false_label = il.DefineLabel();
// IF
codeGenerator.EmitConversion(conditions[0].Condition, PhpTypeCode.Boolean);
il.Emit(OpCodes.Brfalse, false_label);
conditions[0].Statement.Emit(codeGenerator);
codeGenerator.MarkSequencePoint( // (J) Mark the end of condition body so debugger will jump off the block properly
conditions[0].Statement.Position.LastLine, conditions[0].Statement.Position.LastColumn,
conditions[0].Statement.Position.LastLine, conditions[0].Statement.Position.LastColumn + 1);
il.Emit(OpCodes.Br, exit_label);
// ELSEIF:
for (int i = 1; i < conditions.Count && conditions[i].Condition != null; i++)
{
il.MarkLabel(false_label, true);
false_label = il.DefineLabel();
// IF (!<(bool) condition>)
codeGenerator.MarkSequencePoint(conditions[i].Condition); // marks a sequence point of the condition "statement"
codeGenerator.EmitConversion(conditions[i].Condition, PhpTypeCode.Boolean);
il.Emit(OpCodes.Brfalse, false_label);
conditions[i].Statement.Emit(codeGenerator);
il.Emit(OpCodes.Br, exit_label);
}
il.MarkLabel(false_label, true);
// ELSE
if (conditions[conditions.Count - 1].Condition == null)
conditions[conditions.Count - 1].Statement.Emit(codeGenerator);
il.MarkLabel(exit_label, true);
}
/// <include file='Doc/Nodes.xml' path='doc/method[@name="Emit"]/*'/>
internal override void Emit(CodeGenerator codeGenerator)
{
Statistics.AST.AddNode("Loop.For");
// Template:
// we expand the for-statement
// for (<expr1>; <expr2>; <expr3>) <loop body>
// in the while form
// {
// <expr1>;
// while (<expr2>) {
// <loop body>;
// <expr 3>;
// }
// }
Label cond_label = codeGenerator.IL.DefineLabel();
Label iterate_label = codeGenerator.IL.DefineLabel();
Label exit_label = codeGenerator.IL.DefineLabel();
Label stat_label = codeGenerator.IL.DefineLabel();
codeGenerator.BranchingStack.BeginLoop(iterate_label, exit_label,
codeGenerator.ExceptionBlockNestingLevel);
// marks a sequence point containing initialization statements (if any):
if (initExList.Count > 0)
{
codeGenerator.MarkSequencePoint(
initExList[0].Position.FirstLine,
initExList[0].Position.FirstColumn,
initExList[initExList.Count - 1].Position.LastLine,
initExList[initExList.Count - 1].Position.LastColumn + 1);
}
// Emit <expr1>
foreach (Expression expr in initExList)
expr.Emit(codeGenerator);
// Branch unconditionally to the begin of condition evaluation
codeGenerator.IL.Emit(OpCodes.Br, cond_label);
// Emit loop body
codeGenerator.IL.MarkLabel(stat_label);
body.Emit(codeGenerator);
codeGenerator.IL.MarkLabel(iterate_label);
// marks a sequence point containing action statements (if any):
if (actionExList.Count > 0)
{
codeGenerator.MarkSequencePoint(
actionExList[0].Position.FirstLine,
actionExList[0].Position.FirstColumn,
actionExList[actionExList.Count - 1].Position.LastLine,
actionExList[actionExList.Count - 1].Position.LastColumn + 1);
}
// Emit <expr3>
foreach (Expression expr in actionExList)
expr.Emit(codeGenerator);
// marks a sequence point containing condition (if any):
if (condExList.Count > 0)
{
codeGenerator.MarkSequencePoint(
condExList[0].Position.FirstLine,
condExList[0].Position.FirstColumn,
condExList[condExList.Count - 1].Position.LastLine,
condExList[condExList.Count - 1].Position.LastColumn + 1);
}
// Emit <expr2>
codeGenerator.IL.MarkLabel(cond_label);
if (condExList.Count > 0)
{
for (int i = 0; i < (condExList.Count - 1); i++)
condExList[i].Emit(codeGenerator);
// LOAD <(bool) condition>
codeGenerator.EmitConversion(condExList[condExList.Count - 1], PhpTypeCode.Boolean);
}
else
codeGenerator.IL.LdcI4(1);
codeGenerator.IL.Emit(OpCodes.Brtrue, stat_label);
codeGenerator.IL.MarkLabel(exit_label);
codeGenerator.BranchingStack.EndLoop();
codeGenerator.IL.ForgetLabel(cond_label);
codeGenerator.IL.ForgetLabel(iterate_label);
codeGenerator.IL.ForgetLabel(exit_label);
codeGenerator.IL.ForgetLabel(stat_label);
}