From: David Major <dmajor@mozilla.com>
Date: Wed, 9 Jan 2019 23:36:32 +0000 (+0000)
Subject: Don't require a null terminator when loading objects
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=af085b4c8a2f0b36712e58b21aab75741c53c2bf;p=llvm

Don't require a null terminator when loading objects

When a null terminator is required and the file size is a multiple of the system page size, MemoryBuffer will prefer pread() over mmap(), which can result in excessive memory usage.

Patch by Mike Hommey!

Differential Revision: https://reviews.llvm.org/D56475



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350774 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Object/Binary.cpp b/lib/Object/Binary.cpp
index d7c25921ec3..fe41987f5c2 100644
--- a/lib/Object/Binary.cpp
+++ b/lib/Object/Binary.cpp
@@ -88,7 +88,8 @@ Expected<std::unique_ptr<Binary>> object::createBinary(MemoryBufferRef Buffer,
 
 Expected<OwningBinary<Binary>> object::createBinary(StringRef Path) {
   ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
-      MemoryBuffer::getFileOrSTDIN(Path);
+      MemoryBuffer::getFileOrSTDIN(Path, /*FileSize=*/-1,
+                                   /*RequiresNullTerminator=*/false);
   if (std::error_code EC = FileOrErr.getError())
     return errorCodeToError(EC);
   std::unique_ptr<MemoryBuffer> &Buffer = FileOrErr.get();