protected override void VisitBranchOnFalseShortInstruction(BranchOnFalseShortInstruction instruction)
{
ControlState.EvaluationStack.Pop(out var stackVal);
var branch = ComputeUnaryBranchOperation(
stackVal,
a => a.Value == 0,
a => a.Value == 0
);
if (branch)
{
ControlState.Move(instruction.Offset, instruction.Label);
}
else
{
ControlState.MoveToNextInstruction();
}
}
public override CILInstructionBranchTarget BuildNode(ParseTreeNode node)
{
var instructionBranchTargetParseTreeNode = node.GetFirstChildWithGrammarName(GrammarNames.INSTR_BRTARGET);
CILInstructionBranchTarget result = null;
var beqsParseTreeNode = instructionBranchTargetParseTreeNode?.GetFirstChildWithGrammarName(GrammarNames.keyword_beqs);
if (beqsParseTreeNode != null)
{
result = new BranchOnEqualShortInstruction();
}
var bgesParseTreeNode = instructionBranchTargetParseTreeNode?.GetFirstChildWithGrammarName(GrammarNames.keyword_bges);
if (bgesParseTreeNode != null)
{
result = new BranchOnGreaterOrEqualShortInstruction();
}
var blesParseTreeNode = instructionBranchTargetParseTreeNode?.GetFirstChildWithGrammarName(GrammarNames.keyword_bles);
if (blesParseTreeNode != null)
{
result = new BranchOnLessOrEqualShortInstruction();
}
var bltsParseTreeNode = instructionBranchTargetParseTreeNode?.GetFirstChildWithGrammarName(GrammarNames.keyword_blts);
if (bltsParseTreeNode != null)
{
result = new BranchOnLessShortInstruction();
}
var bneunsParseTreeNode = instructionBranchTargetParseTreeNode?.GetFirstChildWithGrammarName(GrammarNames.keyword_bneuns);
if (bneunsParseTreeNode != null)
{
result = new BranchOnNotEqualOrUnorderedShortInstruction();
}
var brParseTreeNode = instructionBranchTargetParseTreeNode?.GetFirstChildWithGrammarName(GrammarNames.keyword_br);
if (brParseTreeNode != null)
{
result = new BranchInstruction();
}
var brfalsesParseTreeNode = instructionBranchTargetParseTreeNode?.GetFirstChildWithGrammarName(GrammarNames.keyword_brfalses);
if (brfalsesParseTreeNode != null)
{
result = new BranchOnFalseShortInstruction();
}
var brsParseTreeNode = instructionBranchTargetParseTreeNode?.GetFirstChildWithGrammarName(GrammarNames.keyword_brs);
if (brsParseTreeNode != null)
{
result = new BranchShortInstruction();
}
var brtruesParseTreeNode = instructionBranchTargetParseTreeNode?.GetFirstChildWithGrammarName(GrammarNames.keyword_brtrues);
if (brtruesParseTreeNode != null)
{
result = new BranchOnTrueShortInstruction();
}
if (result != null)
{
var idParseTreeNode = node.GetFirstChildWithGrammarName(GrammarNames.id);
result.Label = IdParseTreeNodeHelper.GetValue(idParseTreeNode);
return(result);
}
throw new ArgumentException("Cannot recognize CIL instruction branch target.");
}
protected abstract void VisitBranchOnFalseShortInstruction(BranchOnFalseShortInstruction instruction);
