private void BreakReduceLeaveCatch(BasicBlock root, BBLoop loop, BasicBlock breakTarget, LeaveCatchBasicBlock leavebb, Seq<BasicBlock> removed, Seq<BasicBlock> added)
{
if (leavebb.Target.Equals(breakTarget))
{
var instructions = leavebb.Block.CopyContents();
var lci = new BreakContinueInstruction(NextInstructionId--, BreakContinueOp.Break, loop.Label)
{ BeforeState = leavebb.Block.AfterState, AfterState = leavebb.Block.AfterState };
instructions.Add(lci);
var newbb = new NonReturningBasicBlock(nextBlockId++, new Instructions(leavebb.Block.BeforeState, instructions));
root.Coalesce(leavebb, new Set<BasicBlock> { leavebb }, newbb);
removed.Add(leavebb);
added.Add(newbb);
}
}
private void BreakReduceBranch(BasicBlock root, BBLoop loop, BasicBlock breakTarget, BranchBasicBlock branchbb, Seq<BasicBlock> removed, Seq<BasicBlock> added)
{
var beforeState = branchbb.Block.BeforeState;
var afterState = branchbb.Block.AfterState;
if (branchbb.Target.Equals(breakTarget) && !branchbb.Fallthrough.Equals(breakTarget))
{
var instructions = branchbb.Block.CopyContents();
branchbb.Test.Eval(instructions, afterState, branchbb.Target.Block.BeforeState, BottomPT);
var cond = SeparateCondition(beforeState, ref instructions);
var lci = new BreakContinueInstruction(NextInstructionId--, BreakContinueOp.Break, loop.Label)
{ BeforeState = afterState, AfterState = afterState };
var itei = new IfThenElseInstruction(NextInstructionId--, cond, new Instructions(lci), null)
{ BeforeState = beforeState, AfterState = afterState };
instructions.Add(itei);
var newbb = new JumpBasicBlock(nextBlockId++, new Instructions(beforeState, instructions), branchbb.Fallthrough);
root.Coalesce(branchbb, new Set<BasicBlock> { branchbb }, newbb);
removed.Add(branchbb);
added.Add(newbb);
}
else if (branchbb.Fallthrough.Equals(breakTarget) && !branchbb.Target.Equals(breakTarget))
{
var instructions = branchbb.Block.CopyContents();
branchbb.Test.Negate().Eval
(instructions, afterState, branchbb.Fallthrough.Block.BeforeState, BottomPT);
var cond = SeparateCondition(beforeState, ref instructions);
var lci = new BreakContinueInstruction(NextInstructionId--, BreakContinueOp.Break, loop.Label)
{ BeforeState = afterState, AfterState = afterState };
var itei = new IfThenElseInstruction(NextInstructionId--, cond, new Instructions(lci), null)
{ BeforeState = beforeState, AfterState = afterState };
instructions.Add(itei);
var newbb = new JumpBasicBlock(nextBlockId++, new Instructions(beforeState, instructions), branchbb.Target);
root.Coalesce(branchbb, new Set<BasicBlock> { branchbb }, newbb);
removed.Add(branchbb);
added.Add(newbb);
}
}
private string ContinueReduceLeaveTry(BasicBlock root, BBLoop loop, LeaveTryBasicBlock leavebb)
{
if (leavebb.Target.Equals(loop.ContinueTarget) && leavebb.HandlerPopCount == 1)
{
var instructions = leavebb.Block.CopyContents();
var lci = new BreakContinueInstruction(NextInstructionId--, BreakContinueOp.Continue, loop.Label)
{ BeforeState = leavebb.Block.AfterState, AfterState = leavebb.Block.AfterState };
instructions.Add(lci);
var newbb = new NonReturningBasicBlock(nextBlockId++, new Instructions(leavebb.Block.BeforeState, instructions));
root.Coalesce(leavebb, new Set<BasicBlock> { leavebb }, newbb);
return String.Format
("continue from leave try at B{0} within loop from B{1}", leavebb.Id, loop.Head.Id);
}
return null;
}
private string ContinueReduceBranch(BasicBlock root, BBLoop loop, BranchBasicBlock branchbb)
{
var beforeState = branchbb.Block.BeforeState;
var afterState = branchbb.Block.AfterState;
if (branchbb.Target.Equals(loop.ContinueTarget) && !branchbb.Fallthrough.Equals(loop.ContinueTarget) &&
loop.ContinueTarget.Sources.Count > 1)
{
var instructions = branchbb.Block.CopyContents();
branchbb.Test.Eval
(instructions, afterState, branchbb.Target.Block.BeforeState, BottomPT);
var cond = SeparateCondition(beforeState, ref instructions);
var lci = new BreakContinueInstruction(NextInstructionId--, BreakContinueOp.Continue, loop.Label)
{ BeforeState = afterState, AfterState = afterState };
var ifei = new IfThenElseInstruction(-1, cond, new Instructions(lci), null)
{ BeforeState = beforeState, AfterState = afterState };
instructions.Add(ifei);
var newbb = new JumpBasicBlock
(nextBlockId++, new Instructions(beforeState, instructions), branchbb.Fallthrough);
root.Coalesce(branchbb, new Set<BasicBlock> { branchbb }, newbb);
return String.Format("continue from branch at B{0} within loop from B{1}", branchbb.Id, loop.Head.Id);
}
if (branchbb.Fallthrough.Equals(loop.ContinueTarget) && !branchbb.Target.Equals(loop.ContinueTarget) &&
loop.ContinueTarget.Sources.Count > 1)
{
var instructions = branchbb.Block.CopyContents();
branchbb.Test.Negate().Eval
(instructions, afterState, branchbb.Fallthrough.Block.BeforeState, BottomPT);
var cond = SeparateCondition(beforeState, ref instructions);
var lci = new BreakContinueInstruction(NextInstructionId--, BreakContinueOp.Continue, loop.Label)
{ BeforeState = afterState, AfterState = afterState };
var ifei = new IfThenElseInstruction(NextInstructionId--, cond, new Instructions(lci), null)
{ BeforeState = beforeState, AfterState = afterState };
instructions.Add(ifei);
var newbb = new JumpBasicBlock(nextBlockId++, new Instructions(beforeState, instructions), branchbb.Target);
root.Coalesce(branchbb, new Set<BasicBlock> { branchbb }, newbb);
return String.Format
("continue from branch (flipped) at B{0} within loop from B{1}", branchbb.Id, loop.Head.Id);
}
return null;
}
private string ContinueReduceJump(BasicBlock root, BBLoop loop, JumpBasicBlock jumpbb)
{
if (jumpbb.Target.Equals(loop.ContinueTarget) && jumpbb.Block.AfterState.Depth == 0 &&
loop.ContinueTarget.Sources.Count > 1)
{
var instructions = jumpbb.Block.CopyContents();
var lci = new BreakContinueInstruction(NextInstructionId--, BreakContinueOp.Continue, loop.Label)
{ BeforeState = jumpbb.Block.AfterState, AfterState = jumpbb.Block.AfterState };
instructions.Add(lci);
var newbb = new NonReturningBasicBlock
(nextBlockId++, new Instructions(jumpbb.Block.BeforeState, instructions));
root.Coalesce(jumpbb, new Set<BasicBlock> { jumpbb }, newbb);
return String.Format("continue from jump at B{0} within loop from B{1}", jumpbb.Id, loop.Head.Id);
}
return null;
}
