Chris Lattner 2b5e1b5263 Make a few major changes to memdep and its clients: ... 1. Merge the 'None' result into 'Normal', making loads and stores return their dependencies on allocations as Normal. 2. Split the 'Normal' result into 'Clobber' and 'Def' to distinguish between the cases when memdep knows the value is produced from when we just know if may be changed. 3. Move some of the logic for determining whether readonly calls are CSEs into memdep instead of it being in GVN. This still leaves verification that the arguments are hte same to GVN to let it know about value equivalences in different contexts. 4. Change memdep's call/call dependency analysis to use getModRefInfo(CallSite,CallSite) instead of doing something very weak. This only really matters for things like DSA, but someday maybe we'll have some other decent context sensitive analyses :) 5. This reimplements the guts of memdep to handle the new results. 6. This simplifies GVN significantly: a) readonly call CSE is slightly simpler b) I eliminated the "getDependencyFrom" chaining for load elimination and load CSE doesn't have to worry about volatile (they are always clobbers) anymore. c) GVN no longer does any 'lastLoad' caching, leaving it to memdep. 7. The logic in DSE is simplified a bit and sped up. A potentially unsafe case was eliminated. llvm-svn: 60607		2008-12-05 21:04:20 +00:00
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llvm	Make a few major changes to memdep and its clients:	2008-12-05 21:04:20 +00:00
llvm-c	Add protected visibility to libLTO.	2008-11-29 22:49:59 +00:00