1 files changed, 6 insertions, 12 deletions
diff --git a/lib/Support/SourceMgr.cpp b/lib/Support/SourceMgr.cpp
index a55ad881d012..2a241f18c362 100644
--- a/lib/Support/SourceMgr.cpp
+++ b/lib/Support/SourceMgr.cpp
@@ -1,9 +1,8 @@
 //===- SourceMgr.cpp - Manager for Simple Source Buffers & Diagnostics ----===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
+// 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
 //
 //===----------------------------------------------------------------------===//
 //
@@ -96,14 +95,9 @@ unsigned SourceMgr::SrcBuffer::getLineNumber(const char *Ptr) const {
   assert(PtrDiff >= 0 && static_cast<size_t>(PtrDiff) <= std::numeric_limits<T>::max());
   T PtrOffset = static_cast<T>(PtrDiff);
 
-  // std::lower_bound returns the first EOL offset that's not-less-than
-  // PtrOffset, meaning the EOL that _ends the line_ that PtrOffset is on
-  // (including if PtrOffset refers to the EOL itself). If there's no such
-  // EOL, returns end().
-  auto EOL = std::lower_bound(Offsets->begin(), Offsets->end(), PtrOffset);
-
-  // Lines count from 1, so add 1 to the distance from the 0th line.
-  return (1 + (EOL - Offsets->begin()));
+  // llvm::lower_bound gives the number of EOL before PtrOffset. Add 1 to get
+  // the line number.
+  return llvm::lower_bound(*Offsets, PtrOffset) - Offsets->begin() + 1;
 }
 
 SourceMgr::SrcBuffer::SrcBuffer(SourceMgr::SrcBuffer &&Other)