[llvm] [NewPM][CodeGen][llc] Add NPM support (PR #70922)

[Arthur Eubanks via llvm-commits]

================
@@ -0,0 +1,264 @@
+//===- NewPMDriver.cpp - Driver for llc using new PM ----------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+/// \file
+///
+/// This file is just a split of the code that logically belongs in llc.cpp but
+/// that includes the new pass manager headers.
+///
+//===----------------------------------------------------------------------===//
+
+#include "NewPMDriver.h"
+#include "llvm/Analysis/CGSCCPassManager.h"
+#include "llvm/Analysis/TargetLibraryInfo.h"
+#include "llvm/CodeGen/CodeGenPassBuilder.h"
+#include "llvm/CodeGen/CommandFlags.h"
+#include "llvm/CodeGen/MIRParser/MIRParser.h"
+#include "llvm/CodeGen/MIRPrinter.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/MachinePassManager.h"
+#include "llvm/CodeGen/TargetPassConfig.h"
+#include "llvm/IR/DiagnosticInfo.h"
+#include "llvm/IR/DiagnosticPrinter.h"
+#include "llvm/IR/IRPrintingPasses.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/PassManager.h"
+#include "llvm/IR/Verifier.h"
+#include "llvm/IRReader/IRReader.h"
+#include "llvm/Passes/PassBuilder.h"
+#include "llvm/Passes/StandardInstrumentations.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/FormattedStream.h"
+#include "llvm/Support/ToolOutputFile.h"
+#include "llvm/Support/WithColor.h"
+#include "llvm/Target/CGPassBuilderOption.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetOptions.h"
+#include "llvm/Transforms/Scalar/LoopPassManager.h"
+#include "llvm/Transforms/Utils/Cloning.h"
+
+using namespace llvm;
+
+static cl::opt<RegAllocType> RegAlloc(
+    "regalloc-npm", cl::desc("Register allocator to use for new pass manager"),
+    cl::Hidden, cl::ValueOptional, cl::init(RegAllocType::Default),
+    cl::values(
+        clEnumValN(RegAllocType::Default, "default",
+                   "pick register allocator based on -O option"),
+        clEnumValN(RegAllocType::Basic, "basic", "basic register allocator"),
+        clEnumValN(RegAllocType::Fast, "fast", "fast register allocator"),
+        clEnumValN(RegAllocType::Greedy, "greedy", "greedy register allocator"),
+        clEnumValN(RegAllocType::PBQP, "pbqp", "PBQP register allocator")));
+
+static cl::opt<bool>
+    DebugPM("debug-pass-manager", cl::Hidden,
+            cl::desc("Print pass management debugging information"));
+
+bool LLCDiagnosticHandler::handleDiagnostics(const DiagnosticInfo &DI) {
+  if (DI.getKind() == llvm::DK_SrcMgr) {
+    const auto &DISM = cast<DiagnosticInfoSrcMgr>(DI);
+    const SMDiagnostic &SMD = DISM.getSMDiag();
+
+    if (SMD.getKind() == SourceMgr::DK_Error)
+      *HasError = true;
+
+    SMD.print(nullptr, errs());
+
+    // For testing purposes, we print the LocCookie here.
+    if (DISM.isInlineAsmDiag() && DISM.getLocCookie())
+      WithColor::note() << "!srcloc = " << DISM.getLocCookie() << "\n";
+
+    return true;
+  }
+
+  if (DI.getSeverity() == DS_Error)
+    *HasError = true;
+
+  if (auto *Remark = dyn_cast<DiagnosticInfoOptimizationBase>(&DI))
+    if (!Remark->isEnabled())
+      return true;
+
+  DiagnosticPrinterRawOStream DP(errs());
+  errs() << LLVMContext::getDiagnosticMessagePrefix(DI.getSeverity()) << ": ";
+  DI.print(DP);
+  errs() << "\n";
+  return true;
+}
+
+static llvm::ExitOnError ExitOnErr;
+
+static void RunPasses(bool CompileTwice, bool BOS, ToolOutputFile *Out,
+                      Module *M, LLVMContext &Context,
+                      SmallVector<char, 0> &Buffer, ModulePassManager *MPM,
+                      ModuleAnalysisManager *MAM,
+                      MachineFunctionPassManager &MFPM,
+                      MachineFunctionAnalysisManager &MFAM) {
+  auto RunPM = [=, &MFPM, &MFAM]() {
+    if (MPM) {
+      assert(MAM);
+      MPM->run(*M, *MAM);
+    }
+
+    ExitOnErr(MFPM.run(*M, MFAM));
+  };
+
+  assert(M && "invalid input module!");
+
+  // Before executing passes, print the final values of the LLVM options.
+  cl::PrintOptionValues();
+
+  // If requested, run the pass manager over the same module again,
+  // to catch any bugs due to persistent state in the passes. Note that
+  // opt has the same functionality, so it may be worth abstracting this out
+  // in the future.
+  SmallVector<char, 0> CompileTwiceBuffer;
+  if (CompileTwice) {
+    std::unique_ptr<Module> M2(llvm::CloneModule(*M));
+    RunPM();
+    CompileTwiceBuffer = Buffer;
+    Buffer.clear();
+  }
+
+  RunPM();
+
+  auto HasError =
+      ((const LLCDiagnosticHandler *)(Context.getDiagHandlerPtr()))->HasError;
+  if (*HasError)
+    exit(1);
+
+  // Compare the two outputs and make sure they're the same
+  if (CompileTwice) {
----------------
aeubanks wrote:

we haven't guaranteed that reusing a pipeline twice works as expected for the new PM so I'd remove all the `CompileTwice` code until we have that guarantee everywhere

https://github.com/llvm/llvm-project/pull/70922