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-rw-r--r--contrib/llvm-project/llvm/lib/Analysis/LegacyDivergenceAnalysis.cpp43
1 files changed, 31 insertions, 12 deletions
diff --git a/contrib/llvm-project/llvm/lib/Analysis/LegacyDivergenceAnalysis.cpp b/contrib/llvm-project/llvm/lib/Analysis/LegacyDivergenceAnalysis.cpp
index 52212e1c42aa..0f274429f11f 100644
--- a/contrib/llvm-project/llvm/lib/Analysis/LegacyDivergenceAnalysis.cpp
+++ b/contrib/llvm-project/llvm/lib/Analysis/LegacyDivergenceAnalysis.cpp
@@ -64,10 +64,10 @@
//
//===----------------------------------------------------------------------===//
+#include "llvm/Analysis/LegacyDivergenceAnalysis.h"
#include "llvm/ADT/PostOrderIterator.h"
#include "llvm/Analysis/CFG.h"
#include "llvm/Analysis/DivergenceAnalysis.h"
-#include "llvm/Analysis/LegacyDivergenceAnalysis.h"
#include "llvm/Analysis/Passes.h"
#include "llvm/Analysis/PostDominators.h"
#include "llvm/Analysis/TargetTransformInfo.h"
@@ -75,6 +75,8 @@
#include "llvm/IR/InstIterator.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Value.h"
+#include "llvm/InitializePasses.h"
+#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include <vector>
@@ -93,8 +95,9 @@ namespace {
class DivergencePropagator {
public:
DivergencePropagator(Function &F, TargetTransformInfo &TTI, DominatorTree &DT,
- PostDominatorTree &PDT, DenseSet<const Value *> &DV)
- : F(F), TTI(TTI), DT(DT), PDT(PDT), DV(DV) {}
+ PostDominatorTree &PDT, DenseSet<const Value *> &DV,
+ DenseSet<const Use *> &DU)
+ : F(F), TTI(TTI), DT(DT), PDT(PDT), DV(DV), DU(DU) {}
void populateWithSourcesOfDivergence();
void propagate();
@@ -118,11 +121,14 @@ private:
PostDominatorTree &PDT;
std::vector<Value *> Worklist; // Stack for DFS.
DenseSet<const Value *> &DV; // Stores all divergent values.
+ DenseSet<const Use *> &DU; // Stores divergent uses of possibly uniform
+ // values.
};
void DivergencePropagator::populateWithSourcesOfDivergence() {
Worklist.clear();
DV.clear();
+ DU.clear();
for (auto &I : instructions(F)) {
if (TTI.isSourceOfDivergence(&I)) {
Worklist.push_back(&I);
@@ -197,8 +203,10 @@ void DivergencePropagator::exploreSyncDependency(Instruction *TI) {
// dominators of TI until it is outside the influence region.
BasicBlock *InfluencedBB = ThisBB;
while (InfluenceRegion.count(InfluencedBB)) {
- for (auto &I : *InfluencedBB)
- findUsersOutsideInfluenceRegion(I, InfluenceRegion);
+ for (auto &I : *InfluencedBB) {
+ if (!DV.count(&I))
+ findUsersOutsideInfluenceRegion(I, InfluenceRegion);
+ }
DomTreeNode *IDomNode = DT.getNode(InfluencedBB)->getIDom();
if (IDomNode == nullptr)
break;
@@ -208,9 +216,10 @@ void DivergencePropagator::exploreSyncDependency(Instruction *TI) {
void DivergencePropagator::findUsersOutsideInfluenceRegion(
Instruction &I, const DenseSet<BasicBlock *> &InfluenceRegion) {
- for (User *U : I.users()) {
- Instruction *UserInst = cast<Instruction>(U);
+ for (Use &Use : I.uses()) {
+ Instruction *UserInst = cast<Instruction>(Use.getUser());
if (!InfluenceRegion.count(UserInst->getParent())) {
+ DU.insert(&Use);
if (DV.insert(UserInst).second)
Worklist.push_back(UserInst);
}
@@ -250,9 +259,8 @@ void DivergencePropagator::computeInfluenceRegion(
void DivergencePropagator::exploreDataDependency(Value *V) {
// Follow def-use chains of V.
for (User *U : V->users()) {
- Instruction *UserInst = cast<Instruction>(U);
- if (!TTI.isAlwaysUniform(U) && DV.insert(UserInst).second)
- Worklist.push_back(UserInst);
+ if (!TTI.isAlwaysUniform(U) && DV.insert(U).second)
+ Worklist.push_back(U);
}
}
@@ -275,6 +283,9 @@ void DivergencePropagator::propagate() {
// Register this pass.
char LegacyDivergenceAnalysis::ID = 0;
+LegacyDivergenceAnalysis::LegacyDivergenceAnalysis() : FunctionPass(ID) {
+ initializeLegacyDivergenceAnalysisPass(*PassRegistry::getPassRegistry());
+}
INITIALIZE_PASS_BEGIN(LegacyDivergenceAnalysis, "divergence",
"Legacy Divergence Analysis", false, true)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
@@ -320,6 +331,7 @@ bool LegacyDivergenceAnalysis::runOnFunction(Function &F) {
return false;
DivergentValues.clear();
+ DivergentUses.clear();
gpuDA = nullptr;
auto &DT = getAnalysis<DominatorTreeWrapperPass>().getDomTree();
@@ -328,11 +340,11 @@ bool LegacyDivergenceAnalysis::runOnFunction(Function &F) {
if (shouldUseGPUDivergenceAnalysis(F)) {
// run the new GPU divergence analysis
auto &LI = getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
- gpuDA = llvm::make_unique<GPUDivergenceAnalysis>(F, DT, PDT, LI, TTI);
+ gpuDA = std::make_unique<GPUDivergenceAnalysis>(F, DT, PDT, LI, TTI);
} else {
// run LLVM's existing DivergenceAnalysis
- DivergencePropagator DP(F, TTI, DT, PDT, DivergentValues);
+ DivergencePropagator DP(F, TTI, DT, PDT, DivergentValues, DivergentUses);
DP.populateWithSourcesOfDivergence();
DP.propagate();
}
@@ -351,6 +363,13 @@ bool LegacyDivergenceAnalysis::isDivergent(const Value *V) const {
return DivergentValues.count(V);
}
+bool LegacyDivergenceAnalysis::isDivergentUse(const Use *U) const {
+ if (gpuDA) {
+ return gpuDA->isDivergentUse(*U);
+ }
+ return DivergentValues.count(U->get()) || DivergentUses.count(U);
+}
+
void LegacyDivergenceAnalysis::print(raw_ostream &OS, const Module *) const {
if ((!gpuDA || !gpuDA->hasDivergence()) && DivergentValues.empty())
return;