2 Commits

Author	SHA1	Message	Date
Hal Finkel	7c11695a23	Make Value::isDereferenceablePointer handle offsets to pointer types with dereferenceable attributes ... When we have a parameter (or call site return) with a dereferenceable attribute, it can specify the size of an array pointed to by that parameter. If we have a value for which we can accumulate a constant offset to such a parameter, then we can use that offset in a direct comparison with the size specified by the dereferenceable attribute. This enables us to handle cases like this: int foo(int a[static 3]) { return a[2]; /* this is always dereferenceable */ } git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213447 91177308-0d34-0410-b5e6-96231b3b80d8	2014-07-19 03:25:16 +00:00
Hal Finkel	11af4b49b2	Add a dereferenceable attribute ... This attribute indicates that the parameter or return pointer is dereferenceable. Practically speaking, loads from such a pointer within the associated byte range are safe to speculatively execute. Such pointer parameters are common in source languages (C++ references, for example). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213385 91177308-0d34-0410-b5e6-96231b3b80d8	2014-07-18 15:51:28 +00:00