llvm/CMakeLists.txt at 455a0bcfcce8a12503a3029d4d7c4469a5b0c74c - llvm - Gitea: Git with a cup of tea

RPCS3/llvm

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Peter Collingbourne 5a81e14385 Introduce bitset metadata format and bitset lowering pass.

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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230054 91177308-0d34-0410-b5e6-96231b3b80d8

2015-02-20 20:30:47 +00:00

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CMake

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 set(LLVM_LINK_COMPONENTS
   Core
   Support
   IPO
   )
 add_llvm_unittest(IPOTests
   LowerBitSets.cpp
   )