From e890eead222abf84fc171b28891a68b65e9addf5 Mon Sep 17 00:00:00 2001 From: Dan Gohman Date: Fri, 26 Jun 2009 22:17:21 +0000 Subject: [PATCH] Fix SCEVAddRecExpr::isLoopInvariant to test if all of its operands are loop invariant, not just the start operand. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74338 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Analysis/ScalarEvolution.cpp | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp index c98414d66a4..2d8bd7d53a6 100644 --- a/lib/Analysis/ScalarEvolution.cpp +++ b/lib/Analysis/ScalarEvolution.cpp @@ -327,12 +327,22 @@ SCEVAddRecExpr::replaceSymbolicValuesWithConcrete(const SCEV *Sym, bool SCEVAddRecExpr::isLoopInvariant(const Loop *QueryLoop) const { - // This recurrence is invariant w.r.t to QueryLoop iff QueryLoop doesn't - // contain L and if the start is invariant. // Add recurrences are never invariant in the function-body (null loop). - return QueryLoop && - !QueryLoop->contains(L->getHeader()) && - getOperand(0)->isLoopInvariant(QueryLoop); + if (!QueryLoop) + return false; + + // This recurrence is variant w.r.t. QueryLoop if QueryLoop contains L. + if (QueryLoop->contains(L->getHeader())) + return false; + + // This recurrence is variant w.r.t. QueryLoop if any of its operands + // are variant. + for (unsigned i = 0, e = getNumOperands(); i != e; ++i) + if (!getOperand(i)->isLoopInvariant(QueryLoop)) + return false; + + // Otherwise it's loop-invariant. + return true; }