[SIL] Enabled printing canonical module.

To print the module, use the new llvm flag -sil-print-canonical-module
which parallels the existing flag -sil-view-canonical-cfg.  When that
flag is passed, the new pass ModulePrinter is added to the diagnostic
pass pipeline after mandatory diagnostics have run.  The new pass just
prints the module to stdout.

Author: nate-chandler

include/swift/SILOptimizer/PassManager/Passes.def

@@ -308,6 +308,8 @@ PASS(Outliner, "outliner",
      "Function Outlining Optimization")
 PASS(OwnershipModelEliminator, "ownership-model-eliminator",
      "Eliminate Ownership Annotation of SIL")
+PASS(ModulePrinter, "module-printer",
+     "Print the module")
 PASS(NestedSemanticFunctionCheck, "nested-semantic-function-check",
      "Diagnose improperly nested '@_semantics' functions")
 PASS(NonTransparentFunctionOwnershipModelEliminator,

lib/SILOptimizer/PassManager/PassPipeline.cpp

@@ -47,6 +47,10 @@ static llvm::cl::opt<bool> SILViewCanonicalCFG(
     "sil-view-canonical-cfg", llvm::cl::init(false),
     llvm::cl::desc("Enable the sil cfg viewer pass after diagnostics"));
 
+static llvm::cl::opt<bool> SILPrintCanonicalModule(
+    "sil-print-canonical-module", llvm::cl::init(false),
+    llvm::cl::desc("Print the textual SIL module after diagnostics"));
+
 static llvm::cl::opt<bool> SILViewSILGenCFG(
     "sil-view-silgen-cfg", llvm::cl::init(false),
     llvm::cl::desc("Enable the sil cfg viewer pass before diagnostics"));
@@ -64,6 +68,12 @@ static void addCFGPrinterPipeline(SILPassPipelinePlan &P, StringRef Name) {
   P.addCFGPrinter();
 }
 
+static void addModulePrinterPipeline(SILPassPipelinePlan &plan,
+                                     StringRef name) {
+  plan.startPipeline(name);
+  plan.addModulePrinter();
+}
+
 static void addMandatoryDebugSerialization(SILPassPipelinePlan &P) {
   P.startPipeline("Mandatory Debug Serialization");
   P.addOwnershipModelEliminator();
@@ -190,6 +200,9 @@ SILPassPipelinePlan::getDiagnosticPassPipeline(const SILOptions &Options) {
   if (SILViewCanonicalCFG) {
     addCFGPrinterPipeline(P, "SIL View Canonical CFG");
   }
+  if (SILPrintCanonicalModule) {
+    addModulePrinterPipeline(P, "SIL Print Canonical Module");
+  }
   return P;
 }
 

lib/SILOptimizer/UtilityPasses/CMakeLists.txt

@@ -25,6 +25,7 @@ target_sources(swiftSILOptimizer PRIVATE
   LoopInfoPrinter.cpp
   LoopRegionPrinter.cpp
   MemBehaviorDumper.cpp
+  ModulePrinter.cpp
   RCIdentityDumper.cpp
   SerializeSILPass.cpp
   SILDebugInfoGenerator.cpp

lib/SILOptimizer/UtilityPasses/ModulePrinter.cpp

@@ -0,0 +1,38 @@
+//===--- ModulePrinter.cpp - Module printer pass --------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2021 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+//
+// A utility module pass to print the module as textual SIL.
+//
+//===----------------------------------------------------------------------===//
+
+#include "swift/SIL/SILPrintContext.h"
+#include "swift/SILOptimizer/PassManager/Passes.h"
+#include "swift/SILOptimizer/PassManager/Transforms.h"
+
+using namespace swift;
+
+namespace {
+
+class SILModulePrinter : public SILModuleTransform {
+
+  /// The entry point.
+  void run() override {
+    auto *module = getModule();
+    SILPrintContext context(llvm::outs(), /*Verbose*/ true, /*SortedSIL*/ true,
+                            /*PrintFullConvention*/ true);
+    module->print(context);
+  }
+};
+
+} // end anonymous namespace
+
+SILTransform *swift::createModulePrinter() { return new SILModulePrinter(); }