/// Simple Analysis hook. Delete loop L from alias set map.
void deleteAnalysisLoop(Loop *L) override;
+
+ /// Returns an owning pointer to an alias set which incorporates aliasing
+ /// info from all subloops of L, but does not include instructions in L
+ /// itself.
+ AliasSetTracker *collectAliasInfoFromSubLoops(Loop *L);
};
}
assert(L->isLCSSAForm(*DT) && "Loop is not in LCSSA form.");
- CurAST = new AliasSetTracker(*AA);
- // Collect Alias info from subloops.
- for (Loop *InnerL : L->getSubLoops()) {
- AliasSetTracker *InnerAST = LoopToAliasSetMap[InnerL];
- assert(InnerAST && "Where is my AST?");
-
- // What if InnerLoop was modified by other passes ?
- CurAST->add(*InnerAST);
-
- // Once we've incorporated the inner loop's AST into ours, we don't need the
- // subloop's anymore.
- delete InnerAST;
- LoopToAliasSetMap.erase(InnerL);
- }
+ CurAST = collectAliasInfoFromSubLoops(L);
CurLoop = L;
return Changed;
}
+/// Returns an owning pointer to an alias set which incorporates aliasing info
+/// from all subloops of L, but does not include instructions in L itself.
+///
+AliasSetTracker *LICM::collectAliasInfoFromSubLoops(Loop *L) {
+ AliasSetTracker *CurAST = nullptr;
+ for (Loop *InnerL : L->getSubLoops()) {
+ AliasSetTracker *InnerAST = LoopToAliasSetMap[InnerL];
+ assert(InnerAST && "Where is my AST?");
+
+ if (CurAST != nullptr) {
+ // What if InnerLoop was modified by other passes ?
+ CurAST->add(*InnerAST);
+
+ // Once we've incorporated the inner loop's AST into ours, we don't need
+ // the subloop's anymore.
+ delete InnerAST;
+ } else {
+ CurAST = InnerAST;
+ }
+ LoopToAliasSetMap.erase(InnerL);
+ }
+ if (CurAST == nullptr)
+ CurAST = new AliasSetTracker(*AA);
+ return CurAST;
+}
+
/// Simple analysis hook. Clone alias set info.
///
void LICM::cloneBasicBlockAnalysis(BasicBlock *From, BasicBlock *To, Loop *L) {