forked from OSchip/llvm-project
e6909c8e8b
This patch introduces a new mechanism that allows IR modules to co-operatively build pointer sets corresponding to addresses within a given set of globals. One particular use case for this is to allow a C++ program to efficiently verify (at each call site) that a vtable pointer is in the set of valid vtable pointers for the class or its derived classes. One way of doing this is for a toolchain component to build, for each class, a bit set that maps to the memory region allocated for the vtables, such that each 1 bit in the bit set maps to a valid vtable for that class, and lay out the vtables next to each other, to minimize the total size of the bit sets. The patch introduces a metadata format for representing pointer sets, an '@llvm.bitset.test' intrinsic and an LTO lowering pass that lays out the globals and builds the bitsets, and documents the new feature. Differential Revision: http://reviews.llvm.org/D7288 llvm-svn: 230054 |
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| .. | ||
| ADT | ||
| Analysis | ||
| Bitcode | ||
| CodeGen | ||
| DebugInfo | ||
| ExecutionEngine | ||
| IR | ||
| LineEditor | ||
| Linker | ||
| MC | ||
| Option | ||
| ProfileData | ||
| Support | ||
| Transforms | ||
| CMakeLists.txt | ||
| Makefile | ||
| Makefile.unittest | ||