4 Commits

Author	SHA1	Message	Date
Tim Shen	a064622bd3	Re-apply "[SCEV] Strengthen StrengthenNoWrapFlags (reapply r334428)." ... llvm-svn: 337075	2018-07-13 23:58:46 +00:00
Tim Shen	2ed501d656	Revert "[SCEV] Strengthen StrengthenNoWrapFlags (reapply r334428)." ... This reverts commit r336140. Our tests shows that LSR assert fails with it. llvm-svn: 336473	2018-07-06 23:20:35 +00:00
Tim Shen	c7cef4bcc4	[SCEV] Strengthen StrengthenNoWrapFlags (reapply r334428). ... Summary: Comment on Transforms/LoopVersioning/incorrect-phi.ll: With the change SCEV is able to prove that the loop doesn't wrap-self (due to zext i16 to i64), disabling the entire loop versioning pass. Removed the zext and just use i64. Reviewers: sanjoy Subscribers: jlebar, hiraditya, javed.absar, bixia, llvm-commits Differential Revision: https://reviews.llvm.org/D48409 llvm-svn: 336140	2018-07-02 20:01:54 +00:00
Adam Nemet	73a26957fc	[LoopVer] Update all existing PHIs in the exit block ... We only used to add the edge from the cloned loop to PHIs that corresponded to values defined by the loop. We need to do this for all PHIs obviously since we need a PHI operand for each incoming edge. This includes things like PHIs with a constant value or with values defined before the original loop (see the testcases). After the patch the PHIs are added to the exit block in two passes. In the first pass we ensure there is a single-operand (LCSSA) PHI for each value defined by the loop. In the second pass we loop through each (single-operand) PHI and add the value for the edge from the cloned loop. If the value is defined in the loop we'll use the cloned instruction from the cloned loop. Fixes PR28037 llvm-svn: 272649	2016-06-14 09:38:54 +00:00