diff options
Diffstat (limited to 'clang/docs')
| -rw-r--r-- | clang/docs/ControlFlowIntegrityDesign.rst | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/clang/docs/ControlFlowIntegrityDesign.rst b/clang/docs/ControlFlowIntegrityDesign.rst index b4aacd36567..38c5e5b99e3 100644 --- a/clang/docs/ControlFlowIntegrityDesign.rst +++ b/clang/docs/ControlFlowIntegrityDesign.rst @@ -90,10 +90,10 @@ For example on x86 a typical virtual call may look like this: The compiler relies on co-operation from the linker in order to assemble the bit vectors for the whole program. It currently does this using LLVM's -`bit sets`_ mechanism together with link-time optimization. +`type metadata`_ mechanism together with link-time optimization. .. _address point: https://mentorembedded.github.io/cxx-abi/abi.html#vtable-general -.. _bit sets: http://llvm.org/docs/BitSets.html +.. _type metadata: http://llvm.org/docs/TypeMetadata.html .. _ByteArrayBuilder: http://llvm.org/docs/doxygen/html/structllvm_1_1ByteArrayBuilder.html Optimizations @@ -196,7 +196,7 @@ those sub-hierarchies need to be (see "Stripping Leading/Trailing Zeros in Bit Vectors" above). The `GlobalLayoutBuilder`_ class is responsible for laying out the globals efficiently to minimize the sizes of the underlying bitsets. -.. _GlobalLayoutBuilder: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/IPO/LowerBitSets.h?view=markup +.. _GlobalLayoutBuilder: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/IPO/LowerTypeTests.h?view=markup Alignment ~~~~~~~~~ @@ -297,8 +297,8 @@ file's symbol table, the symbols for the target functions also refer to the jump table entries, so that addresses taken outside the module will pass any verification done inside the module. -In more concrete terms, suppose we have three functions ``f``, ``g``, ``h`` -which are members of a single bitset, and a function foo that returns their +In more concrete terms, suppose we have three functions ``f``, ``g``, +``h`` which are all of the same type, and a function foo that returns their addresses: .. code-block:: none @@ -439,10 +439,10 @@ export this information, every DSO implements void __cfi_check(uint64 CallSiteTypeId, void *TargetAddr) -This function provides external modules with access to CFI checks for -the targets inside this DSO. For each known ``CallSiteTypeId``, this -functions performs an ``llvm.bitset.test`` with the corresponding bit -set. It aborts if the type is unknown, or if the check fails. +This function provides external modules with access to CFI checks for the +targets inside this DSO. For each known ``CallSiteTypeId``, this function +performs an ``llvm.type.test`` with the corresponding type identifier. It +aborts if the type is unknown, or if the check fails. The basic implementation is a large switch statement over all values of CallSiteTypeId supported by this DSO, and each case is similar to |
