llvm-6502/lib/Transforms
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
..
Hello
InstCombine [InstCombine] Remove unnecessary variable indexing into single-element arrays 2015-02-20 03:05:53 +00:00
Instrumentation [sanitizer] when dumping the basic block trace, also dump the module names. Patch by Laszlo Szekeres 2015-02-20 00:30:44 +00:00
IPO Introduce bitset metadata format and bitset lowering pass. 2015-02-20 20:30:47 +00:00
ObjCARC [objc-arc-contract] We can not move retains over instructions which can not conservatively be proven to not decrement the retain's RCIdentity. 2015-02-20 00:02:49 +00:00
Scalar [GC, RewriteStatepointsForGC] Style cleanup and bug fix 2015-02-20 19:51:56 +00:00
Utils
Vectorize
CMakeLists.txt
LLVMBuild.txt
Makefile