/** * Run all jobs in the work list (and any children they have) to completion. This method returns * <code>true</code> if all jobs were successfully completed. If all jobs were successfully * completed, then the worklist will be empty. * * <p>The scheduling of <code>Job</code>s uses two methods to maintain scheduling invariants: * <code>selectJobFromWorklist</code> selects a <code>SourceJob</code> from <code>worklist</code> * (a list of jobs that still need to be processed); <code>enforceInvariants</code> is called * before a pass is performed on a <code>SourceJob</code> and is responsible for ensuring all * dependencies are satisfied before the pass proceeds, i.e. enforcing any scheduling invariants. */ public boolean runToCompletion() { boolean okay = true; while (okay && !worklist.isEmpty()) { SourceJob job = selectJobFromWorklist(); if (Report.should_report(Report.frontend, 1)) { Report.report(1, "Running job " + job); } okay &= runAllPasses(job); if (job.completed()) { // the job has finished. Let's remove it from the map so it // can be garbage collected, and free up the AST. jobs.put(job.source(), COMPLETED_JOB); if (Report.should_report(Report.frontend, 1)) { Report.report(1, "Completed job " + job); } } else { // the job is not yet completed (although, it really // should be...) if (Report.should_report(Report.frontend, 1)) { Report.report(1, "Failed to complete job " + job); } worklist.add(job); } } if (Report.should_report(Report.frontend, 1)) Report.report(1, "Finished all passes -- " + (okay ? "okay" : "failed")); return okay; }
/** * Add a new <code>SourceJob</code> for the <code>Source source</code>, with AST <code>ast</code>. * A new job will be created if needed. If the <code>Source source</code> has already been * processed, and its job discarded to release resources, then <code>null</code> will be returned. */ public SourceJob addJob(Source source, Node ast) { Object o = jobs.get(source); SourceJob job = null; if (o == COMPLETED_JOB) { // the job has already been completed. // We don't need to add a job return null; } else if (o == null) { // No appropriate job yet exists, we will create one. job = this.createSourceJob(source, ast); // record the job in the map and the worklist. jobs.put(source, job); worklist.addLast(job); if (Report.should_report(Report.frontend, 3)) { Report.report(3, "Adding job for " + source + " at the " + "request of job " + currentJob); } } else { job = (SourceJob) o; } // if the current source job caused this job to load, record the // dependency. if (currentJob instanceof SourceJob) { ((SourceJob) currentJob).addDependency(source); } return job; }
/** * Before running <code>Pass pass</code> on <code>SourceJob job</code> make sure that all * appropriate scheduling invariants are satisfied, to ensure that all passes of other jobs that * <code>job</code> depends on will have already been done. */ protected void enforceInvariants(Job job, Pass pass) throws CyclicDependencyException { SourceJob srcJob = job.sourceJob(); if (srcJob == null) { return; } BarrierPass lastBarrier = srcJob.lastBarrier(); if (lastBarrier != null) { // make sure that _all_ dependent jobs have completed at least up to // the last barrier (not just children). // // Ideally the invariant should be that only the source jobs that // job _depends on_ should be brought up to the last barrier. // This is work to be done in the future... List allDependentSrcs = new ArrayList(srcJob.dependencies()); Iterator i = allDependentSrcs.iterator(); while (i.hasNext()) { Source s = (Source) i.next(); Object o = jobs.get(s); if (o == COMPLETED_JOB) continue; if (o == null) { throw new InternalCompilerError("Unknown source " + s); } SourceJob sj = (SourceJob) o; if (sj.pending(lastBarrier.id())) { // Make the job run up to the last barrier. // We ignore the return result, since even if the job // fails, we will keep on going and see // how far we get... if (Report.should_report(Report.frontend, 3)) { Report.report(3, "Running " + sj + " to " + lastBarrier.id() + " for " + srcJob); } runToPass(sj, lastBarrier.id()); } } } if (pass instanceof GlobalBarrierPass) { // need to make sure that _all_ jobs have completed just up to // this global barrier. // If we hit a cyclic dependency, ignore it and run the other // jobs up to that pass. Then try again to run the cyclic // pass. If we hit the cycle again for the same job, stop. LinkedList barrierWorklist = new LinkedList(jobs.values()); while (!barrierWorklist.isEmpty()) { Object o = barrierWorklist.removeFirst(); if (o == COMPLETED_JOB) continue; SourceJob sj = (SourceJob) o; if (sj.completed(pass.id()) || sj.nextPass() == sj.passByID(pass.id())) { // the source job has either done this global pass // (which is possible if the job was loaded late in the // game), or is right up to the global barrier. continue; } // Make the job run up to just before the global barrier. // We ignore the return result, since even if the job // fails, we will keep on going and see // how far we get... Pass beforeGlobal = sj.getPreviousTo(pass.id()); if (Report.should_report(Report.frontend, 3)) { Report.report(3, "Running " + sj + " to " + beforeGlobal.id() + " for " + srcJob); } // Don't use runToPass, since that catches the // CyclicDependencyException that we should report // back to the caller. while (!sj.pendingPasses().isEmpty()) { Pass p = (Pass) sj.pendingPasses().get(0); runPass(sj, p); if (p == beforeGlobal) { break; } } } } }