[llvm] [CodeGen] Allow `CodeGenPassBuilder` to add module pass after function pass (PR #77084)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,158 @@
+//===- llvm/unittest/CodeGen/CodeGenPassBuilderTest.cpp -------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/CodeGenPassBuilder.h"
+#include "llvm/CodeGen/MachinePassManager.h"
+#include "llvm/CodeGen/TargetPassConfig.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/TargetRegistry.h"
+#include "llvm/Passes/PassBuilder.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/TargetSelect.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/TargetParser/Host.h"
+#include "gtest/gtest.h"
+#include <string>
+
+using namespace llvm;
+
+namespace {
+
+struct NoOpModulePass : PassInfoMixin<NoOpModulePass> {
+  PreservedAnalyses run(Module &M, ModuleAnalysisManager &) {
+    return PreservedAnalyses::all();
+  }
+
+  static StringRef name() { return "NoOpModulePass"; }
+};
+
+struct NoOpFunctionPass : PassInfoMixin<NoOpFunctionPass> {
+  PreservedAnalyses run(Function &F, FunctionAnalysisManager &) {
+    return PreservedAnalyses::all();
+  }
+  static StringRef name() { return "NoOpFunctionPass"; }
+};
+
+class DummyCodeGenPassBuilder
+    : public CodeGenPassBuilder<DummyCodeGenPassBuilder> {
+public:
+  DummyCodeGenPassBuilder(LLVMTargetMachine &TM, CGPassBuilderOption Opts,
+                          PassInstrumentationCallbacks *PIC)
+      : CodeGenPassBuilder(TM, Opts, PIC){};
+
+  void addPreISel(AddIRPass &addPass) const {
+    addPass(NoOpModulePass());
+    addPass(NoOpFunctionPass());
+    addPass(NoOpFunctionPass());
+    addPass(NoOpFunctionPass());
+    addPass(NoOpModulePass());
+    addPass(NoOpFunctionPass());
+  }
+
+  void addAsmPrinter(AddMachinePass &, CreateMCStreamer) const {}
+
+  Error addInstSelector(AddMachinePass &) const { return Error::success(); }
+};
+
+class CodeGenPassBuilderTest : public testing::Test {
+public:
+  LLVMTargetMachine *TM;
+
+  static void SetUpTestCase() {
+    InitializeAllTargets();
+    InitializeAllTargetMCs();
+
+    static const char *argv[] = {
+        "test",
+        "-print-pipeline-passes",
+    };
+    int argc = sizeof(argv) / sizeof(char *);
+    cl::ParseCommandLineOptions(argc, argv);
+  }
+
+  void SetUp() override {
+    std::string TripleName = Triple::normalize(sys::getDefaultTargetTriple());
+    std::string Error;
+    const Target *TheTarget = TargetRegistry::lookupTarget(TripleName, Error);
+    if (!TheTarget)
+      GTEST_SKIP();
+
+    TargetOptions Options;
+    TM = static_cast<LLVMTargetMachine *>(
+        TheTarget->createTargetMachine("", "", "", Options, std::nullopt));
+  }
+};
+
+TEST_F(CodeGenPassBuilderTest, basic) {
+  LoopAnalysisManager LAM;
+  FunctionAnalysisManager FAM;
+  CGSCCAnalysisManager CGAM;
+  ModuleAnalysisManager MAM;
+
+  PassInstrumentationCallbacks PIC;
+  DummyCodeGenPassBuilder CGPB(*TM, getCGPassBuilderOption(), &PIC);
+  PipelineTuningOptions PTO;
+  PassBuilder PB(TM, PTO, std::nullopt, &PIC);
+
+  PB.registerModuleAnalyses(MAM);
+  PB.registerCGSCCAnalyses(CGAM);
+  PB.registerFunctionAnalyses(FAM);
+  PB.registerLoopAnalyses(LAM);
+  PB.crossRegisterProxies(LAM, FAM, CGAM, MAM);
+
+  ModulePassManager MPM;
+  MachineFunctionPassManager MFPM;
+  Error Err =
+      CGPB.buildPipeline(MPM, MFPM, outs(), nullptr, CodeGenFileType::Null);
+  EXPECT_FALSE(Err);
+
+  std::string IRPipeline;
+  raw_string_ostream IROS(IRPipeline);
+  MPM.printPipeline(IROS, [&PIC](StringRef Name) {
+    auto PassName = PIC.getPassNameForClassName(Name);
+    return PassName.empty() ? Name : PassName;
+  });
+  char ExpectedIRPipeline[] =
+      "require<profile-summary>,require<collector-metadata>,"
+      "PreISelIntrinsicLoweringPass,function(verify,loop-mssa(loop-reduce),"
+      "mergeicmps,expand-memcmp,gc-lowering),shadow-stack-gc-lowering,function("
+      "lower-constant-intrinsics,UnreachableBlockElimPass,consthoist,"
+      "ReplaceWithVeclib,partially-inline-libcalls,ee-instrument<post-inline>,"
+      "scalarize-masked-mem-intrin,ExpandReductionsPass,codegenprepare,"
+      "dwarf-eh-prepare),no-op-module,function(no-op-function,no-op-function,"
+      "no-op-function),no-op-module,function(no-op-function,callbrprepare,"
+      "safe-stack,stack-protector,verify)";
+  EXPECT_EQ(IRPipeline, ExpectedIRPipeline);
+
+  std::string MIRPipeline;
+  raw_string_ostream MIROS(MIRPipeline);
+  MFPM.printPipeline(MIROS, [&PIC](StringRef Name) {
+    auto PassName = PIC.getPassNameForClassName(Name);
+    return PassName.empty() ? Name : PassName;
+  });
+  char ExpectedMIRPipeline[] =
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arsenm wrote:

const?

https://github.com/llvm/llvm-project/pull/77084