[PATCH] D115384: Support: Avoid using SmallVector::set_size() in MemoryBuffer

Duncan P. N. Exon Smith via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Thu Dec 9 18:45:17 PST 2021


This revision was landed with ongoing or failed builds.
This revision was automatically updated to reflect the committed changes.
Closed by commit rG1131738698c4: Support: Avoid using SmallVector::set_size() in MemoryBuffer (authored by dexonsmith).

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D115384/new/

https://reviews.llvm.org/D115384

Files:
  llvm/lib/Support/MemoryBuffer.cpp


Index: llvm/lib/Support/MemoryBuffer.cpp
===================================================================
--- llvm/lib/Support/MemoryBuffer.cpp
+++ llvm/lib/Support/MemoryBuffer.cpp
@@ -227,17 +227,20 @@
 getMemoryBufferForStream(sys::fs::file_t FD, const Twine &BufferName) {
   const ssize_t ChunkSize = 4096*4;
   SmallString<ChunkSize> Buffer;
+
   // Read into Buffer until we hit EOF.
+  size_t Size = Buffer.size();
   for (;;) {
-    Buffer.reserve(Buffer.size() + ChunkSize);
+    Buffer.resize_for_overwrite(Size + ChunkSize);
     Expected<size_t> ReadBytes = sys::fs::readNativeFile(
-        FD, makeMutableArrayRef(Buffer.end(), ChunkSize));
+        FD, makeMutableArrayRef(Buffer.begin() + Size, ChunkSize));
     if (!ReadBytes)
       return errorToErrorCode(ReadBytes.takeError());
     if (*ReadBytes == 0)
       break;
-    Buffer.set_size(Buffer.size() + *ReadBytes);
+    Size += *ReadBytes;
   }
+  Buffer.truncate(Size);
 
   return getMemBufferCopyImpl(Buffer, BufferName);
 }


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D115384.393362.patch
Type: text/x-patch
Size: 1007 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20211210/d1eda871/attachment.bin>


More information about the llvm-commits mailing list