[JITLink] Assert that segment mapping does not exceed allocation size.

diff --git a/llvm/lib/ExecutionEngine/JITLink/JITLinkMemoryManager.cpp b/llvm/lib/ExecutionEngine/JITLink/JITLinkMemoryManager.cpp
index 63a9b7b..36067cc 100644 (file)
--- a/llvm/lib/ExecutionEngine/JITLink/JITLinkMemoryManager.cpp
+++ b/llvm/lib/ExecutionEngine/JITLink/JITLinkMemoryManager.cpp
@@ -113,6 +113,8 @@ InProcessMemoryManager::allocate(const JITLinkDylib *JD,
 
     uint64_t SegmentSize = alignTo(Seg.getContentSize() + Seg.getZeroFillSize(),
                                    sys::Process::getPageSizeEstimate());
+    assert(SlabRemaining.allocatedSize() >= SegmentSize &&
+           "Mapping exceeds allocation");
 
     sys::MemoryBlock SegMem(SlabRemaining.base(), SegmentSize);
     SlabRemaining = sys::MemoryBlock((char *)SlabRemaining.base() + SegmentSize,