53 Commits

Author	SHA1	Message	Date
Dan Gohman	f5a309e989	Use a sign-extend instead of a zero-extend when promoting a ... trip count value when the original loop iteration condition is signed and the canonical induction variable won't undergo signed overflow. This isn't required for correctness; it just preserves more information about original loop iteration values. Add a getTruncateOrSignExtend method to ScalarEvolution, following getTruncateOrZeroExtend. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64918 91177308-0d34-0410-b5e6-96231b3b80d8	2009-02-18 17:22:41 +00:00
Dan Gohman	d2067fd730	Fix a corner case in the new indvars promotion logic: if there ... are multiple IV's in a loop, some of them may under go signed or unsigned wrapping even if the IV that's used in the loop exit condition doesn't. Restrict sign-extension-elimination and zero-extension-elimination to only those that operate on the original loop-controlling IV. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64866 91177308-0d34-0410-b5e6-96231b3b80d8	2009-02-18 00:52:00 +00:00
Dan Gohman	74786c0f43	Rename IndVarsSimplify to IndVarSimplify, to be consistent with ... the name used in the code that these tests are for. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64624 91177308-0d34-0410-b5e6-96231b3b80d8	2009-02-16 00:56:15 +00:00