diff options
Diffstat (limited to 'contrib/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp')
| -rw-r--r-- | contrib/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp | 108 |
1 files changed, 70 insertions, 38 deletions
diff --git a/contrib/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp b/contrib/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp index 8fb5801..20b37c4 100644 --- a/contrib/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp +++ b/contrib/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp @@ -20,13 +20,14 @@ // //===----------------------------------------------------------------------===// +#include "llvm/Transforms/Scalar/LoopLoadElimination.h" #include "llvm/ADT/APInt.h" #include "llvm/ADT/DenseMap.h" #include "llvm/ADT/DepthFirstIterator.h" +#include "llvm/ADT/STLExtras.h" #include "llvm/ADT/SmallSet.h" #include "llvm/ADT/SmallVector.h" #include "llvm/ADT/Statistic.h" -#include "llvm/ADT/STLExtras.h" #include "llvm/Analysis/GlobalsModRef.h" #include "llvm/Analysis/LoopAccessAnalysis.h" #include "llvm/Analysis/LoopInfo.h" @@ -45,9 +46,9 @@ #include "llvm/Support/Debug.h" #include "llvm/Transforms/Scalar.h" #include "llvm/Transforms/Utils/LoopVersioning.h" -#include <forward_list> -#include <cassert> #include <algorithm> +#include <cassert> +#include <forward_list> #include <set> #include <tuple> #include <utility> @@ -196,8 +197,7 @@ public: continue; // Only progagate the value if they are of the same type. - if (Store->getPointerOperand()->getType() != - Load->getPointerOperand()->getType()) + if (Store->getPointerOperandType() != Load->getPointerOperandType()) continue; Candidates.emplace_front(Load, Store); @@ -373,15 +373,15 @@ public: const auto &AllChecks = LAI.getRuntimePointerChecking()->getChecks(); SmallVector<RuntimePointerChecking::PointerCheck, 4> Checks; - std::copy_if(AllChecks.begin(), AllChecks.end(), std::back_inserter(Checks), - [&](const RuntimePointerChecking::PointerCheck &Check) { - for (auto PtrIdx1 : Check.first->Members) - for (auto PtrIdx2 : Check.second->Members) - if (needsChecking(PtrIdx1, PtrIdx2, - PtrsWrittenOnFwdingPath, CandLoadPtrs)) - return true; - return false; - }); + copy_if(AllChecks, std::back_inserter(Checks), + [&](const RuntimePointerChecking::PointerCheck &Check) { + for (auto PtrIdx1 : Check.first->Members) + for (auto PtrIdx2 : Check.second->Members) + if (needsChecking(PtrIdx1, PtrIdx2, PtrsWrittenOnFwdingPath, + CandLoadPtrs)) + return true; + return false; + }); DEBUG(dbgs() << "\nPointer Checks (count: " << Checks.size() << "):\n"); DEBUG(LAI.getRuntimePointerChecking()->printChecks(dbgs(), Checks)); @@ -558,6 +558,32 @@ private: PredicatedScalarEvolution PSE; }; +static bool +eliminateLoadsAcrossLoops(Function &F, LoopInfo &LI, DominatorTree &DT, + function_ref<const LoopAccessInfo &(Loop &)> GetLAI) { + // Build up a worklist of inner-loops to transform to avoid iterator + // invalidation. + // FIXME: This logic comes from other passes that actually change the loop + // nest structure. It isn't clear this is necessary (or useful) for a pass + // which merely optimizes the use of loads in a loop. + SmallVector<Loop *, 8> Worklist; + + for (Loop *TopLevelLoop : LI) + for (Loop *L : depth_first(TopLevelLoop)) + // We only handle inner-most loops. + if (L->empty()) + Worklist.push_back(L); + + // Now walk the identified inner loops. + bool Changed = false; + for (Loop *L : Worklist) { + // The actual work is performed by LoadEliminationForLoop. + LoadEliminationForLoop LEL(L, &LI, GetLAI(*L), &DT); + Changed |= LEL.processLoop(); + } + return Changed; +} + /// \brief The pass. Most of the work is delegated to the per-loop /// LoadEliminationForLoop class. class LoopLoadElimination : public FunctionPass { @@ -570,32 +596,14 @@ public: if (skipFunction(F)) return false; - auto *LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo(); - auto *LAA = &getAnalysis<LoopAccessLegacyAnalysis>(); - auto *DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree(); - - // Build up a worklist of inner-loops to vectorize. This is necessary as the - // act of distributing a loop creates new loops and can invalidate iterators - // across the loops. - SmallVector<Loop *, 8> Worklist; - - for (Loop *TopLevelLoop : *LI) - for (Loop *L : depth_first(TopLevelLoop)) - // We only handle inner-most loops. - if (L->empty()) - Worklist.push_back(L); - - // Now walk the identified inner loops. - bool Changed = false; - for (Loop *L : Worklist) { - const LoopAccessInfo &LAI = LAA->getInfo(L); - // The actual work is performed by LoadEliminationForLoop. - LoadEliminationForLoop LEL(L, LI, LAI, DT); - Changed |= LEL.processLoop(); - } + auto &LI = getAnalysis<LoopInfoWrapperPass>().getLoopInfo(); + auto &LAA = getAnalysis<LoopAccessLegacyAnalysis>(); + auto &DT = getAnalysis<DominatorTreeWrapperPass>().getDomTree(); // Process each loop nest in the function. - return Changed; + return eliminateLoadsAcrossLoops( + F, LI, DT, + [&LAA](Loop &L) -> const LoopAccessInfo & { return LAA.getInfo(&L); }); } void getAnalysisUsage(AnalysisUsage &AU) const override { @@ -631,4 +639,28 @@ FunctionPass *createLoopLoadEliminationPass() { return new LoopLoadElimination(); } +PreservedAnalyses LoopLoadEliminationPass::run(Function &F, + FunctionAnalysisManager &AM) { + auto &SE = AM.getResult<ScalarEvolutionAnalysis>(F); + auto &LI = AM.getResult<LoopAnalysis>(F); + auto &TTI = AM.getResult<TargetIRAnalysis>(F); + auto &DT = AM.getResult<DominatorTreeAnalysis>(F); + auto &TLI = AM.getResult<TargetLibraryAnalysis>(F); + auto &AA = AM.getResult<AAManager>(F); + auto &AC = AM.getResult<AssumptionAnalysis>(F); + + auto &LAM = AM.getResult<LoopAnalysisManagerFunctionProxy>(F).getManager(); + bool Changed = eliminateLoadsAcrossLoops( + F, LI, DT, [&](Loop &L) -> const LoopAccessInfo & { + LoopStandardAnalysisResults AR = {AA, AC, DT, LI, SE, TLI, TTI}; + return LAM.getResult<LoopAccessAnalysis>(L, AR); + }); + + if (!Changed) + return PreservedAnalyses::all(); + + PreservedAnalyses PA; + return PA; +} + } // end namespace llvm |
