commit 098eaffc0c1784567ddccfe6f976ced6e904552e
author Dylan Noblesmith <nobled@dreamwidth.org> Mon Dec 19 08:51:05 2011 +0000
committer Dylan Noblesmith <nobled@dreamwidth.org> Mon Dec 19 08:51:05 2011 +0000
tree 6a44445209ca1c4b83124a0b318b424167a235bb
parent 2c2a385a1abef4d4b0b9f3712db3859da404b5eb

SourceManager: use getBufferSize()

Forming an out of bounds pointer to check if it's out
of bounds was undefined behavior.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@146861 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Basic/SourceManager.cpp

diff --git a/lib/Basic/SourceManager.cpp b/lib/Basic/SourceManager.cpp
index 5221ed4..310b68e 100644
--- a/lib/Basic/SourceManager.cpp
+++ b/lib/Basic/SourceManager.cpp
@@ -962,13 +962,13 @@
   if (MyInvalid)
     return 1;
 
-  const char *Buf = MemBuf->getBufferStart();
-  if (Buf + FilePos >= MemBuf->getBufferEnd()) {
+  if (FilePos >= MemBuf->getBufferSize()) {
     if (Invalid)
       *Invalid = MyInvalid;
     return 1;
   }
 
+  const char *Buf = MemBuf->getBufferStart();
   unsigned LineStart = FilePos;
   while (LineStart && Buf[LineStart-1] != '\n' && Buf[LineStart-1] != '\r')
     --LineStart;
@@ -1524,9 +1524,10 @@
     return FileLoc.getLocWithOffset(Size);
   }
 
+  const llvm::MemoryBuffer *Buffer = Content->getBuffer(Diag, *this);
   unsigned FilePos = Content->SourceLineCache[Line - 1];
-  const char *Buf = Content->getBuffer(Diag, *this)->getBufferStart() + FilePos;
-  unsigned BufLength = Content->getBuffer(Diag, *this)->getBufferEnd() - Buf;
+  const char *Buf = Buffer->getBufferStart() + FilePos;
+  unsigned BufLength = Buffer->getBufferSize() - FilePos;
   if (BufLength == 0)
     return FileLoc.getLocWithOffset(FilePos);