/// <summary>
/// This callback is called from the SccFinder, which passes it a list
/// of Procedures that form a SCC.
/// </summary>
/// <param name="procs"></param>
private void UntangleProcedureScc(IList <Procedure> procs)
{
this.sccProcs = procs.ToHashSet();
flow.CreateFlowsFor(procs);
// Convert all procedures in the SCC to SSA form and perform
// value propagation.
var ssts = procs.Select(ConvertToSsa).ToArray();
this.ssts.AddRange(ssts);
DumpWatchedProcedure("After extra stack vars", ssts);
// At this point, the computation of ProcedureFlow is possible.
var trf = new TrashedRegisterFinder(program, flow, ssts, this.eventListener);
trf.Compute();
// New stack based variables may be available now.
foreach (var sst in ssts)
{
var vp = new ValuePropagator(program.SegmentMap, sst.SsaState, program.CallGraph, dynamicLinker, this.eventListener);
vp.Transform();
sst.RenameFrameAccesses = true;
sst.Transform();
DumpWatchedProcedure("After extra stack vars", sst.SsaState.Procedure);
}
foreach (var ssa in ssts.Select(sst => sst.SsaState))
{
RemoveImplicitRegistersFromHellNodes(ssa);
var sac = new SegmentedAccessClassifier(ssa);
sac.Classify();
var prj = new ProjectionPropagator(ssa, sac);
prj.Transform();
DumpWatchedProcedure("After projection propagation", ssa.Procedure);
}
var uid = new UsedRegisterFinder(flow, procs, this.eventListener);
foreach (var sst in ssts)
{
var ssa = sst.SsaState;
RemovePreservedUseInstructions(ssa);
DeadCode.Eliminate(ssa);
uid.ComputeLiveIn(ssa, true);
var procFlow = flow[ssa.Procedure];
RemoveDeadArgumentsFromCalls(ssa.Procedure, procFlow, ssts);
DumpWatchedProcedure("After dead call argument removal", ssa.Procedure);
}
eventListener.Advance(procs.Count);
}
/// <summary>
/// Finds all interprocedural register dependencies (in- and out-parameters) and
/// abstracts them away by rewriting as calls.
/// </summary>
/// <returns>A RegisterLiveness object that summarizes the interprocedural register
/// liveness analysis. This information can be used to generate SSA form.
/// </returns>
public void UntangleProcedures()
{
eventListener.ShowStatus("Eliminating intra-block dead registers.");
IntraBlockDeadRegisters.Apply(program);
eventListener.ShowStatus("Finding terminating procedures.");
var term = new TerminationAnalysis(flow);
term.Analyze(program);
eventListener.ShowStatus("Finding trashed registers.");
var trf = new TrashedRegisterFinder(program, program.Procedures.Values, flow, eventListener);
trf.Compute();
eventListener.ShowStatus("Rewriting affine expressions.");
trf.RewriteBasicBlocks();
eventListener.ShowStatus("Computing register liveness.");
var rl = RegisterLiveness.Compute(program, flow, eventListener);
eventListener.ShowStatus("Rewriting calls.");
GlobalCallRewriter.Rewrite(program, flow);
}
/// <summary>
/// Finds all interprocedural register dependencies (in- and out-parameters) and
/// abstracts them away by rewriting as calls.
/// </summary>
/// <returns>A RegisterLiveness object that summarizes the interprocedural register
/// liveness analysis. This information can be used to generate SSA form.
/// </returns>
public void UntangleProcedures()
{
eventListener.ShowStatus("Eliminating intra-block dead registers.");
var usb = new UserSignatureBuilder(program);
usb.BuildSignatures(eventListener);
CallRewriter.Rewrite(program, eventListener);
IntraBlockDeadRegisters.Apply(program, eventListener);
AdjacentBranchCollector.Transform(program, eventListener);
eventListener.ShowStatus("Finding terminating procedures.");
var term = new TerminationAnalysis(flow, eventListener);
term.Analyze(program);
eventListener.ShowStatus("Finding trashed registers.");
var trf = new TrashedRegisterFinder(program, program.Procedures.Values, flow, eventListener);
trf.Compute();
eventListener.ShowStatus("Rewriting affine expressions.");
trf.RewriteBasicBlocks();
eventListener.ShowStatus("Computing register liveness.");
RegisterLiveness.Compute(program, flow, eventListener);
eventListener.ShowStatus("Rewriting calls.");
GlobalCallRewriter.Rewrite(program, flow, eventListener);
}