1 files changed, 56 insertions, 0 deletions
diff --git a/llvm/lib/IR/OptBisect.cpp b/llvm/lib/IR/OptBisect.cpp
new file mode 100644
index 000000000000..3104b90f3070
--- /dev/null
+++ b/llvm/lib/IR/OptBisect.cpp
@@ -0,0 +1,56 @@
+//===- llvm/IR/OptBisect/Bisect.cpp - LLVM Bisect support -----------------===//
+//
+// 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 implements support for a bisecting optimizations based on a
+/// command line option.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/IR/OptBisect.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/raw_ostream.h"
+#include <cassert>
+#include <limits>
+#include <string>
+
+using namespace llvm;
+
+static cl::opt<int> OptBisectLimit("opt-bisect-limit", cl::Hidden,
+                                   cl::init(std::numeric_limits<int>::max()),
+                                   cl::Optional,
+                                   cl::desc("Maximum optimization to perform"));
+
+OptBisect::OptBisect() : OptPassGate() {
+  BisectEnabled = OptBisectLimit != std::numeric_limits<int>::max();
+}
+
+static void printPassMessage(const StringRef &Name, int PassNum,
+                             StringRef TargetDesc, bool Running) {
+  StringRef Status = Running ? "" : "NOT ";
+  errs() << "BISECT: " << Status << "running pass "
+         << "(" << PassNum << ") " << Name << " on " << TargetDesc << "\n";
+}
+
+bool OptBisect::shouldRunPass(const Pass *P, StringRef IRDescription) {
+  assert(BisectEnabled);
+
+  return checkPass(P->getPassName(), IRDescription);
+}
+
+bool OptBisect::checkPass(const StringRef PassName,
+                          const StringRef TargetDesc) {
+  assert(BisectEnabled);
+
+  int CurBisectNum = ++LastBisectNum;
+  bool ShouldRun = (OptBisectLimit == -1 || CurBisectNum <= OptBisectLimit);
+  printPassMessage(PassName, CurBisectNum, TargetDesc, ShouldRun);
+  return ShouldRun;
+}