diff options
Diffstat (limited to 'lib/Target')
| -rw-r--r-- | lib/Target/README.txt | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/lib/Target/README.txt b/lib/Target/README.txt index ac56a7d488..f39d8b2a24 100644 --- a/lib/Target/README.txt +++ b/lib/Target/README.txt @@ -595,3 +595,21 @@ to make it so the scheduler doesn't need to hold all the loads in regs at once. //===---------------------------------------------------------------------===// + +We should extend parameter attributes to capture more information about +pointer parameters for alias analysis. Some ideas: + +1. Add a "nocapture" attribute, which indicates that the callee does not store + the address of the parameter into a global or any other memory location + visible to the callee. This can be used to make basicaa and other analyses + more powerful. It is true for things like memcpy, strcat, and many other + things, including structs passed by value, most C++ references, etc. +2. Generalize readonly to be set on parameters. This is important mod/ref + info for the function, which is important for basicaa and others. It can + also be used by the inliner to avoid inserting a memcpy for byval + arguments when the function is inlined. + +These functions can be inferred by various analysis passes such as the +globalsmodrefaa pass. + +//===---------------------------------------------------------------------===// |