From bad65c3b708accec8c6e85346dabc7967cb3d7ca Mon Sep 17 00:00:00 2001 From: Bruno Cardoso Lopes Date: Mon, 22 Dec 2014 22:35:46 +0000 Subject: [LCSSA] Handle PHI insertion in disjoint loops Take two disjoint Loops L1 and L2. LoopSimplify fails to simplify some loops (e.g. when indirect branches are involved). In such situations, it can happen that an exit for L1 is the header of L2. Thus, when we create PHIs in one of such exits we are also inserting PHIs in L2 header. This could break LCSSA form for L2 because these inserted PHIs can also have uses in L2 exits, which are never handled in the current implementation. Provide a fix for this corner case and test that we don't assert/crash on that. Differential Revision: http://reviews.llvm.org/D6624 rdar://problem/19166231 llvm-svn: 224740 --- llvm/lib/Transforms/Scalar/LICM.cpp | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'llvm/lib/Transforms/Scalar/LICM.cpp') diff --git a/llvm/lib/Transforms/Scalar/LICM.cpp b/llvm/lib/Transforms/Scalar/LICM.cpp index 99725b5f738..f07158a6cb1 100644 --- a/llvm/lib/Transforms/Scalar/LICM.cpp +++ b/llvm/lib/Transforms/Scalar/LICM.cpp @@ -316,7 +316,8 @@ bool LICM::runOnLoop(Loop *L, LPPassManager &LPM) { // SSAUpdater strategy during promotion that was LCSSA aware and reformed // it as it went. if (Changed) - formLCSSARecursively(*L, *DT, getAnalysisIfAvailable()); + formLCSSARecursively(*L, *DT, LI, + getAnalysisIfAvailable()); } // Check that neither this loop nor its parent have had LCSSA broken. LICM is -- cgit v1.2.3