diff options
| -rw-r--r-- | polly/lib/CodeGen/BlockGenerators.cpp | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/polly/lib/CodeGen/BlockGenerators.cpp b/polly/lib/CodeGen/BlockGenerators.cpp index 6f26d51dcaa..260ad6ee9c6 100644 --- a/polly/lib/CodeGen/BlockGenerators.cpp +++ b/polly/lib/CodeGen/BlockGenerators.cpp @@ -91,9 +91,12 @@ Value *BlockGenerator::trySynthesizeNewValue(ScopStmt &Stmt, Value *Old, Value *BlockGenerator::getNewValue(ScopStmt &Stmt, Value *Old, ValueMapT &BBMap, LoopToScevMapT <S, Loop *L) const { - // We assume constants never change. - // This avoids map lookups for many calls to this function. - if (isa<Constant>(Old)) + // Constants that do not reference any named value can always remain + // unchanged. Handle them early to avoid expensive map loopups. We do not take + // the fast-path for external constants which are referenced through globals + // as these may need to be rewritten when distributing code accross different + // LLVM modules. + if (isa<Constant>(Old) && !isa<GlobalValue>(Old)) return Old; if (Value *New = GlobalMap.lookup(Old)) { |
