Support, IR, ADT: Check nullptr after allocation with malloc/realloc or calloc

As a follow up of the bad alloc handler patch, this patch introduces nullptr checks on pointers returned from the
malloc/realloc/calloc functions.  In addition some memory size assignments  are moved behind the allocation
of the corresponding memory to fulfill exception safe memory management (RAII).

patch by Klaus Kretzschmar

Differential Revision: https://reviews.llvm.org/D35414

llvm-svn: 308576

1 files changed, 4 insertions, 1 deletions

diff --git a/llvm/lib/Support/SmallVector.cpp b/llvm/lib/Support/SmallVector.cpp
index b931505..74313151 100644
--- a/llvm/lib/Support/SmallVector.cpp
+++ b/llvm/lib/Support/SmallVector.cpp
@@ -26,14 +26,17 @@ void SmallVectorBase::grow_pod(void *FirstEl, size_t MinSizeInBytes,
   void *NewElts;
   if (BeginX == FirstEl) {
     NewElts = malloc(NewCapacityInBytes);
+    if (NewElts == nullptr)
+      report_bad_alloc_error("Allocation of SmallVector element failed.");
 
     // Copy the elements over.  No need to run dtors on PODs.
     memcpy(NewElts, this->BeginX, CurSizeBytes);
   } else {
     // If this wasn't grown from the inline copy, grow the allocated space.
     NewElts = realloc(this->BeginX, NewCapacityInBytes);
+    if (NewElts == nullptr)
+      report_bad_alloc_error("Reallocation of SmallVector element failed.");
   }
-  assert(NewElts && "Out of memory");
 
   this->EndX = (char*)NewElts+CurSizeBytes;
   this->BeginX = NewElts;