//
//===----------------------------------------------------------------------===//
+#include "llvm/Transforms/Scalar/LoopDataPrefetch.h"
+
#define DEBUG_TYPE "loop-data-prefetch"
#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/Statistic.h"
STATISTIC(NumPrefetches, "Number of prefetches inserted");
-namespace llvm {
- void initializeLoopDataPrefetchPass(PassRegistry&);
-}
-
namespace {
- class LoopDataPrefetch : public FunctionPass {
- public:
- static char ID; // Pass ID, replacement for typeid
- LoopDataPrefetch() : FunctionPass(ID) {
- initializeLoopDataPrefetchPass(*PassRegistry::getPassRegistry());
- }
+/// Loop prefetch implementation class.
+class LoopDataPrefetch {
+public:
+ LoopDataPrefetch(AssumptionCache *AC, LoopInfo *LI, ScalarEvolution *SE,
+ const TargetTransformInfo *TTI,
+ OptimizationRemarkEmitter *ORE)
+ : AC(AC), LI(LI), SE(SE), TTI(TTI), ORE(ORE) {}
- void getAnalysisUsage(AnalysisUsage &AU) const override {
- AU.addRequired<AssumptionCacheTracker>();
- AU.addPreserved<DominatorTreeWrapperPass>();
- AU.addRequired<LoopInfoWrapperPass>();
- AU.addPreserved<LoopInfoWrapperPass>();
- AU.addRequired<OptimizationRemarkEmitterWrapperPass>();
- AU.addRequired<ScalarEvolutionWrapperPass>();
- // FIXME: For some reason, preserving SE here breaks LSR (even if
- // this pass changes nothing).
- // AU.addPreserved<ScalarEvolutionWrapperPass>();
- AU.addRequired<TargetTransformInfoWrapperPass>();
- }
+ bool run();
- bool runOnFunction(Function &F) override;
+private:
+ bool runOnLoop(Loop *L);
- private:
- bool runOnLoop(Loop *L);
+ /// \brief Check if the the stride of the accesses is large enough to
+ /// warrant a prefetch.
+ bool isStrideLargeEnough(const SCEVAddRecExpr *AR);
- /// \brief Check if the the stride of the accesses is large enough to
- /// warrant a prefetch.
- bool isStrideLargeEnough(const SCEVAddRecExpr *AR);
+ unsigned getMinPrefetchStride() {
+ if (MinPrefetchStride.getNumOccurrences() > 0)
+ return MinPrefetchStride;
+ return TTI->getMinPrefetchStride();
+ }
- unsigned getMinPrefetchStride() {
- if (MinPrefetchStride.getNumOccurrences() > 0)
- return MinPrefetchStride;
- return TTI->getMinPrefetchStride();
- }
+ unsigned getPrefetchDistance() {
+ if (PrefetchDistance.getNumOccurrences() > 0)
+ return PrefetchDistance;
+ return TTI->getPrefetchDistance();
+ }
- unsigned getPrefetchDistance() {
- if (PrefetchDistance.getNumOccurrences() > 0)
- return PrefetchDistance;
- return TTI->getPrefetchDistance();
- }
+ unsigned getMaxPrefetchIterationsAhead() {
+ if (MaxPrefetchIterationsAhead.getNumOccurrences() > 0)
+ return MaxPrefetchIterationsAhead;
+ return TTI->getMaxPrefetchIterationsAhead();
+ }
- unsigned getMaxPrefetchIterationsAhead() {
- if (MaxPrefetchIterationsAhead.getNumOccurrences() > 0)
- return MaxPrefetchIterationsAhead;
- return TTI->getMaxPrefetchIterationsAhead();
- }
+ AssumptionCache *AC;
+ LoopInfo *LI;
+ ScalarEvolution *SE;
+ const TargetTransformInfo *TTI;
+ OptimizationRemarkEmitter *ORE;
+};
+
+/// Legacy class for inserting loop data prefetches.
+class LoopDataPrefetchLegacyPass : public FunctionPass {
+public:
+ static char ID; // Pass ID, replacement for typeid
+ LoopDataPrefetchLegacyPass() : FunctionPass(ID) {
+ initializeLoopDataPrefetchLegacyPassPass(*PassRegistry::getPassRegistry());
+ }
- AssumptionCache *AC;
- LoopInfo *LI;
- ScalarEvolution *SE;
- const TargetTransformInfo *TTI;
- const DataLayout *DL;
- OptimizationRemarkEmitter *ORE;
+ void getAnalysisUsage(AnalysisUsage &AU) const override {
+ AU.addRequired<AssumptionCacheTracker>();
+ AU.addPreserved<DominatorTreeWrapperPass>();
+ AU.addRequired<LoopInfoWrapperPass>();
+ AU.addPreserved<LoopInfoWrapperPass>();
+ AU.addRequired<OptimizationRemarkEmitterWrapperPass>();
+ AU.addRequired<ScalarEvolutionWrapperPass>();
+ // FIXME: For some reason, preserving SE here breaks LSR (even if
+ // this pass changes nothing).
+ // AU.addPreserved<ScalarEvolutionWrapperPass>();
+ AU.addRequired<TargetTransformInfoWrapperPass>();
+ }
+
+ bool runOnFunction(Function &F) override;
};
}
-char LoopDataPrefetch::ID = 0;
-INITIALIZE_PASS_BEGIN(LoopDataPrefetch, "loop-data-prefetch",
+char LoopDataPrefetchLegacyPass::ID = 0;
+INITIALIZE_PASS_BEGIN(LoopDataPrefetchLegacyPass, "loop-data-prefetch",
"Loop Data Prefetch", false, false)
INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)
INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(OptimizationRemarkEmitterWrapperPass)
INITIALIZE_PASS_DEPENDENCY(ScalarEvolutionWrapperPass)
-INITIALIZE_PASS_END(LoopDataPrefetch, "loop-data-prefetch",
+INITIALIZE_PASS_END(LoopDataPrefetchLegacyPass, "loop-data-prefetch",
"Loop Data Prefetch", false, false)
-FunctionPass *llvm::createLoopDataPrefetchPass() { return new LoopDataPrefetch(); }
+FunctionPass *llvm::createLoopDataPrefetchPass() {
+ return new LoopDataPrefetchLegacyPass();
+}
bool LoopDataPrefetch::isStrideLargeEnough(const SCEVAddRecExpr *AR) {
unsigned TargetMinStride = getMinPrefetchStride();
return TargetMinStride <= AbsStride;
}
-bool LoopDataPrefetch::runOnFunction(Function &F) {
+PreservedAnalyses LoopDataPrefetchPass::run(Function &F,
+ FunctionAnalysisManager &AM) {
+ LoopInfo *LI = &AM.getResult<LoopAnalysis>(F);
+ ScalarEvolution *SE = &AM.getResult<ScalarEvolutionAnalysis>(F);
+ AssumptionCache *AC = &AM.getResult<AssumptionAnalysis>(F);
+ OptimizationRemarkEmitter *ORE =
+ &AM.getResult<OptimizationRemarkEmitterAnalysis>(F);
+ const TargetTransformInfo *TTI = &AM.getResult<TargetIRAnalysis>(F);
+
+ LoopDataPrefetch LDP(AC, LI, SE, TTI, ORE);
+ bool Changed = LDP.run();
+
+ if (Changed) {
+ PreservedAnalyses PA;
+ PA.preserve<DominatorTreeAnalysis>();
+ PA.preserve<LoopAnalysis>();
+ return PA;
+ }
+
+ return PreservedAnalyses::all();
+}
+
+bool LoopDataPrefetchLegacyPass::runOnFunction(Function &F) {
if (skipFunction(F))
return false;
- LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
- SE = &getAnalysis<ScalarEvolutionWrapperPass>().getSE();
- DL = &F.getParent()->getDataLayout();
- AC = &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
- ORE = &getAnalysis<OptimizationRemarkEmitterWrapperPass>().getORE();
- TTI = &getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
+ LoopInfo *LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
+ ScalarEvolution *SE = &getAnalysis<ScalarEvolutionWrapperPass>().getSE();
+ AssumptionCache *AC =
+ &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
+ OptimizationRemarkEmitter *ORE =
+ &getAnalysis<OptimizationRemarkEmitterWrapperPass>().getORE();
+ const TargetTransformInfo *TTI =
+ &getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
+
+ LoopDataPrefetch LDP(AC, LI, SE, TTI, ORE);
+ return LDP.run();
+}
+bool LoopDataPrefetch::run() {
// If PrefetchDistance is not set, don't run the pass. This gives an
// opportunity for targets to run this pass for selected subtargets only
// (whose TTI sets PrefetchDistance).