[PATCH] D97320: Use a fast path when initializing LineOffsetMapping

[Chris Lattner via Phabricator via cfe-commits]

lattner added a comment.

Nice, thanks!


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D97320/new/

https://reviews.llvm.org/D97320

___
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits

[PATCH] D97320: Use a fast path when initializing LineOffsetMapping

[serge via Phabricator via cfe-commits]

This revision was landed with ongoing or failed builds.
This revision was automatically updated to reflect the committed changes.
Closed by commit rG80e8efd563fd: Use a fast path when initializing 
LineOffsetMapping (authored by serge-sans-paille).
Herald added a project: clang.
Herald added a subscriber: cfe-commits.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D97320/new/

https://reviews.llvm.org/D97320

Files:
  clang/lib/Basic/SourceManager.cpp


Index: clang/lib/Basic/SourceManager.cpp
===
--- clang/lib/Basic/SourceManager.cpp
+++ clang/lib/Basic/SourceManager.cpp
@@ -1270,13 +1270,16 @@
   const std::size_t BufLen = End - Buf;
   unsigned I = 0;
   while (I < BufLen) {
-if (Buf[I] == '\n') {
-  LineOffsets.push_back(I + 1);
-} else if (Buf[I] == '\r') {
-  // If this is \r\n, skip both characters.
-  if (I + 1 < BufLen && Buf[I + 1] == '\n')
-++I;
-  LineOffsets.push_back(I + 1);
+// Use a fast check to catch both newlines
+if (LLVM_UNLIKELY(Buf[I] <= std::max('\n', '\r'))) {
+  if (Buf[I] == '\n') {
+LineOffsets.push_back(I + 1);
+  } else if (Buf[I] == '\r') {
+// If this is \r\n, skip both characters.
+if (I + 1 < BufLen && Buf[I + 1] == '\n')
+  ++I;
+LineOffsets.push_back(I + 1);
+  }
 }
 ++I;
   }


Index: clang/lib/Basic/SourceManager.cpp
===
--- clang/lib/Basic/SourceManager.cpp
+++ clang/lib/Basic/SourceManager.cpp
@@ -1270,13 +1270,16 @@
   const std::size_t BufLen = End - Buf;
   unsigned I = 0;
   while (I < BufLen) {
-if (Buf[I] == '\n') {
-  LineOffsets.push_back(I + 1);
-} else if (Buf[I] == '\r') {
-  // If this is \r\n, skip both characters.
-  if (I + 1 < BufLen && Buf[I + 1] == '\n')
-++I;
-  LineOffsets.push_back(I + 1);
+// Use a fast check to catch both newlines
+if (LLVM_UNLIKELY(Buf[I] <= std::max('\n', '\r'))) {
+  if (Buf[I] == '\n') {
+LineOffsets.push_back(I + 1);
+  } else if (Buf[I] == '\r') {
+// If this is \r\n, skip both characters.
+if (I + 1 < BufLen && Buf[I + 1] == '\n')
+  ++I;
+LineOffsets.push_back(I + 1);
+  }
 }
 ++I;
   }
___
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits