Clarify interface

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12805 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2004-04-10 06:11:29 +00:00
parent 5364360294
commit 94c420da4a

View File

@ -102,7 +102,8 @@ public:
/// doesNotAccessMemory - If the specified function is known to never read or
/// write memory, return true. If the function only reads from known-constant
/// memory, it is also legal to return true.
/// memory, it is also legal to return true. Functions that unwind the stack
/// are not legal for this predicate.
///
/// Many optimizations (such as CSE and LICM) can be performed on calls to it,
/// without worrying about aliasing properties, and many functions have this
@ -113,7 +114,8 @@ public:
virtual bool doesNotAccessMemory(Function *F) { return false; }
/// onlyReadsMemory - If the specified function is known to only read from
/// non-volatile memory (or not access memory at all), return true.
/// non-volatile memory (or not access memory at all), return true. Functions
/// that unwind the stack are not legal for this predicate.
///
/// This property allows many common optimizations to be performed in the
/// absence of interfering store instructions, such as CSE of strlen calls.