aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/libs/llvm12/lib/Analysis/DDG.cpp
diff options
context:
space:
mode:
authorDevtools Arcadia <arcadia-devtools@yandex-team.ru>2022-02-07 18:08:42 +0300
committerDevtools Arcadia <arcadia-devtools@mous.vla.yp-c.yandex.net>2022-02-07 18:08:42 +0300
commit1110808a9d39d4b808aef724c861a2e1a38d2a69 (patch)
treee26c9fed0de5d9873cce7e00bc214573dc2195b7 /contrib/libs/llvm12/lib/Analysis/DDG.cpp
downloadydb-1110808a9d39d4b808aef724c861a2e1a38d2a69.tar.gz
intermediate changes
ref:cde9a383711a11544ce7e107a78147fb96cc4029
Diffstat (limited to 'contrib/libs/llvm12/lib/Analysis/DDG.cpp')
-rw-r--r--contrib/libs/llvm12/lib/Analysis/DDG.cpp323
1 files changed, 323 insertions, 0 deletions
diff --git a/contrib/libs/llvm12/lib/Analysis/DDG.cpp b/contrib/libs/llvm12/lib/Analysis/DDG.cpp
new file mode 100644
index 0000000000..da5de75a03
--- /dev/null
+++ b/contrib/libs/llvm12/lib/Analysis/DDG.cpp
@@ -0,0 +1,323 @@
+//===- DDG.cpp - Data Dependence Graph -------------------------------------==//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// The implementation for the data dependence graph.
+//===----------------------------------------------------------------------===//
+#include "llvm/Analysis/DDG.h"
+#include "llvm/ADT/SCCIterator.h"
+#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/Analysis/LoopIterator.h"
+#include "llvm/Support/CommandLine.h"
+
+using namespace llvm;
+
+static cl::opt<bool> SimplifyDDG(
+ "ddg-simplify", cl::init(true), cl::Hidden, cl::ZeroOrMore,
+ cl::desc(
+ "Simplify DDG by merging nodes that have less interesting edges."));
+
+static cl::opt<bool>
+ CreatePiBlocks("ddg-pi-blocks", cl::init(true), cl::Hidden, cl::ZeroOrMore,
+ cl::desc("Create pi-block nodes."));
+
+#define DEBUG_TYPE "ddg"
+
+template class llvm::DGEdge<DDGNode, DDGEdge>;
+template class llvm::DGNode<DDGNode, DDGEdge>;
+template class llvm::DirectedGraph<DDGNode, DDGEdge>;
+
+//===--------------------------------------------------------------------===//
+// DDGNode implementation
+//===--------------------------------------------------------------------===//
+DDGNode::~DDGNode() {}
+
+bool DDGNode::collectInstructions(
+ llvm::function_ref<bool(Instruction *)> const &Pred,
+ InstructionListType &IList) const {
+ assert(IList.empty() && "Expected the IList to be empty on entry.");
+ if (isa<SimpleDDGNode>(this)) {
+ for (Instruction *I : cast<const SimpleDDGNode>(this)->getInstructions())
+ if (Pred(I))
+ IList.push_back(I);
+ } else if (isa<PiBlockDDGNode>(this)) {
+ for (const DDGNode *PN : cast<const PiBlockDDGNode>(this)->getNodes()) {
+ assert(!isa<PiBlockDDGNode>(PN) && "Nested PiBlocks are not supported.");
+ SmallVector<Instruction *, 8> TmpIList;
+ PN->collectInstructions(Pred, TmpIList);
+ llvm::append_range(IList, TmpIList);
+ }
+ } else
+ llvm_unreachable("unimplemented type of node");
+ return !IList.empty();
+}
+
+raw_ostream &llvm::operator<<(raw_ostream &OS, const DDGNode::NodeKind K) {
+ const char *Out;
+ switch (K) {
+ case DDGNode::NodeKind::SingleInstruction:
+ Out = "single-instruction";
+ break;
+ case DDGNode::NodeKind::MultiInstruction:
+ Out = "multi-instruction";
+ break;
+ case DDGNode::NodeKind::PiBlock:
+ Out = "pi-block";
+ break;
+ case DDGNode::NodeKind::Root:
+ Out = "root";
+ break;
+ case DDGNode::NodeKind::Unknown:
+ Out = "?? (error)";
+ break;
+ }
+ OS << Out;
+ return OS;
+}
+
+raw_ostream &llvm::operator<<(raw_ostream &OS, const DDGNode &N) {
+ OS << "Node Address:" << &N << ":" << N.getKind() << "\n";
+ if (isa<SimpleDDGNode>(N)) {
+ OS << " Instructions:\n";
+ for (const Instruction *I : cast<const SimpleDDGNode>(N).getInstructions())
+ OS.indent(2) << *I << "\n";
+ } else if (isa<PiBlockDDGNode>(&N)) {
+ OS << "--- start of nodes in pi-block ---\n";
+ auto &Nodes = cast<const PiBlockDDGNode>(&N)->getNodes();
+ unsigned Count = 0;
+ for (const DDGNode *N : Nodes)
+ OS << *N << (++Count == Nodes.size() ? "" : "\n");
+ OS << "--- end of nodes in pi-block ---\n";
+ } else if (!isa<RootDDGNode>(N))
+ llvm_unreachable("unimplemented type of node");
+
+ OS << (N.getEdges().empty() ? " Edges:none!\n" : " Edges:\n");
+ for (auto &E : N.getEdges())
+ OS.indent(2) << *E;
+ return OS;
+}
+
+//===--------------------------------------------------------------------===//
+// SimpleDDGNode implementation
+//===--------------------------------------------------------------------===//
+
+SimpleDDGNode::SimpleDDGNode(Instruction &I)
+ : DDGNode(NodeKind::SingleInstruction), InstList() {
+ assert(InstList.empty() && "Expected empty list.");
+ InstList.push_back(&I);
+}
+
+SimpleDDGNode::SimpleDDGNode(const SimpleDDGNode &N)
+ : DDGNode(N), InstList(N.InstList) {
+ assert(((getKind() == NodeKind::SingleInstruction && InstList.size() == 1) ||
+ (getKind() == NodeKind::MultiInstruction && InstList.size() > 1)) &&
+ "constructing from invalid simple node.");
+}
+
+SimpleDDGNode::SimpleDDGNode(SimpleDDGNode &&N)
+ : DDGNode(std::move(N)), InstList(std::move(N.InstList)) {
+ assert(((getKind() == NodeKind::SingleInstruction && InstList.size() == 1) ||
+ (getKind() == NodeKind::MultiInstruction && InstList.size() > 1)) &&
+ "constructing from invalid simple node.");
+}
+
+SimpleDDGNode::~SimpleDDGNode() { InstList.clear(); }
+
+//===--------------------------------------------------------------------===//
+// PiBlockDDGNode implementation
+//===--------------------------------------------------------------------===//
+
+PiBlockDDGNode::PiBlockDDGNode(const PiNodeList &List)
+ : DDGNode(NodeKind::PiBlock), NodeList(List) {
+ assert(!NodeList.empty() && "pi-block node constructed with an empty list.");
+}
+
+PiBlockDDGNode::PiBlockDDGNode(const PiBlockDDGNode &N)
+ : DDGNode(N), NodeList(N.NodeList) {
+ assert(getKind() == NodeKind::PiBlock && !NodeList.empty() &&
+ "constructing from invalid pi-block node.");
+}
+
+PiBlockDDGNode::PiBlockDDGNode(PiBlockDDGNode &&N)
+ : DDGNode(std::move(N)), NodeList(std::move(N.NodeList)) {
+ assert(getKind() == NodeKind::PiBlock && !NodeList.empty() &&
+ "constructing from invalid pi-block node.");
+}
+
+PiBlockDDGNode::~PiBlockDDGNode() { NodeList.clear(); }
+
+//===--------------------------------------------------------------------===//
+// DDGEdge implementation
+//===--------------------------------------------------------------------===//
+
+raw_ostream &llvm::operator<<(raw_ostream &OS, const DDGEdge::EdgeKind K) {
+ const char *Out;
+ switch (K) {
+ case DDGEdge::EdgeKind::RegisterDefUse:
+ Out = "def-use";
+ break;
+ case DDGEdge::EdgeKind::MemoryDependence:
+ Out = "memory";
+ break;
+ case DDGEdge::EdgeKind::Rooted:
+ Out = "rooted";
+ break;
+ case DDGEdge::EdgeKind::Unknown:
+ Out = "?? (error)";
+ break;
+ }
+ OS << Out;
+ return OS;
+}
+
+raw_ostream &llvm::operator<<(raw_ostream &OS, const DDGEdge &E) {
+ OS << "[" << E.getKind() << "] to " << &E.getTargetNode() << "\n";
+ return OS;
+}
+
+//===--------------------------------------------------------------------===//
+// DataDependenceGraph implementation
+//===--------------------------------------------------------------------===//
+using BasicBlockListType = SmallVector<BasicBlock *, 8>;
+
+DataDependenceGraph::DataDependenceGraph(Function &F, DependenceInfo &D)
+ : DependenceGraphInfo(F.getName().str(), D) {
+ // Put the basic blocks in program order for correct dependence
+ // directions.
+ BasicBlockListType BBList;
+ for (auto &SCC : make_range(scc_begin(&F), scc_end(&F)))
+ append_range(BBList, SCC);
+ std::reverse(BBList.begin(), BBList.end());
+ DDGBuilder(*this, D, BBList).populate();
+}
+
+DataDependenceGraph::DataDependenceGraph(Loop &L, LoopInfo &LI,
+ DependenceInfo &D)
+ : DependenceGraphInfo(Twine(L.getHeader()->getParent()->getName() + "." +
+ L.getHeader()->getName())
+ .str(),
+ D) {
+ // Put the basic blocks in program order for correct dependence
+ // directions.
+ LoopBlocksDFS DFS(&L);
+ DFS.perform(&LI);
+ BasicBlockListType BBList;
+ append_range(BBList, make_range(DFS.beginRPO(), DFS.endRPO()));
+ DDGBuilder(*this, D, BBList).populate();
+}
+
+DataDependenceGraph::~DataDependenceGraph() {
+ for (auto *N : Nodes) {
+ for (auto *E : *N)
+ delete E;
+ delete N;
+ }
+}
+
+bool DataDependenceGraph::addNode(DDGNode &N) {
+ if (!DDGBase::addNode(N))
+ return false;
+
+ // In general, if the root node is already created and linked, it is not safe
+ // to add new nodes since they may be unreachable by the root. However,
+ // pi-block nodes need to be added after the root node is linked, and they are
+ // always reachable by the root, because they represent components that are
+ // already reachable by root.
+ auto *Pi = dyn_cast<PiBlockDDGNode>(&N);
+ assert((!Root || Pi) &&
+ "Root node is already added. No more nodes can be added.");
+
+ if (isa<RootDDGNode>(N))
+ Root = &N;
+
+ if (Pi)
+ for (DDGNode *NI : Pi->getNodes())
+ PiBlockMap.insert(std::make_pair(NI, Pi));
+
+ return true;
+}
+
+const PiBlockDDGNode *DataDependenceGraph::getPiBlock(const NodeType &N) const {
+ if (PiBlockMap.find(&N) == PiBlockMap.end())
+ return nullptr;
+ auto *Pi = PiBlockMap.find(&N)->second;
+ assert(PiBlockMap.find(Pi) == PiBlockMap.end() &&
+ "Nested pi-blocks detected.");
+ return Pi;
+}
+
+raw_ostream &llvm::operator<<(raw_ostream &OS, const DataDependenceGraph &G) {
+ for (DDGNode *Node : G)
+ // Avoid printing nodes that are part of a pi-block twice. They will get
+ // printed when the pi-block is printed.
+ if (!G.getPiBlock(*Node))
+ OS << *Node << "\n";
+ OS << "\n";
+ return OS;
+}
+
+//===--------------------------------------------------------------------===//
+// DDGBuilder implementation
+//===--------------------------------------------------------------------===//
+
+bool DDGBuilder::areNodesMergeable(const DDGNode &Src,
+ const DDGNode &Tgt) const {
+ // Only merge two nodes if they are both simple nodes and the consecutive
+ // instructions after merging belong to the same BB.
+ const auto *SimpleSrc = dyn_cast<const SimpleDDGNode>(&Src);
+ const auto *SimpleTgt = dyn_cast<const SimpleDDGNode>(&Tgt);
+ if (!SimpleSrc || !SimpleTgt)
+ return false;
+
+ return SimpleSrc->getLastInstruction()->getParent() ==
+ SimpleTgt->getFirstInstruction()->getParent();
+}
+
+void DDGBuilder::mergeNodes(DDGNode &A, DDGNode &B) {
+ DDGEdge &EdgeToFold = A.back();
+ assert(A.getEdges().size() == 1 && EdgeToFold.getTargetNode() == B &&
+ "Expected A to have a single edge to B.");
+ assert(isa<SimpleDDGNode>(&A) && isa<SimpleDDGNode>(&B) &&
+ "Expected simple nodes");
+
+ // Copy instructions from B to the end of A.
+ cast<SimpleDDGNode>(&A)->appendInstructions(*cast<SimpleDDGNode>(&B));
+
+ // Move to A any outgoing edges from B.
+ for (DDGEdge *BE : B)
+ Graph.connect(A, BE->getTargetNode(), *BE);
+
+ A.removeEdge(EdgeToFold);
+ destroyEdge(EdgeToFold);
+ Graph.removeNode(B);
+ destroyNode(B);
+}
+
+bool DDGBuilder::shouldSimplify() const { return SimplifyDDG; }
+
+bool DDGBuilder::shouldCreatePiBlocks() const { return CreatePiBlocks; }
+
+//===--------------------------------------------------------------------===//
+// DDG Analysis Passes
+//===--------------------------------------------------------------------===//
+
+/// DDG as a loop pass.
+DDGAnalysis::Result DDGAnalysis::run(Loop &L, LoopAnalysisManager &AM,
+ LoopStandardAnalysisResults &AR) {
+ Function *F = L.getHeader()->getParent();
+ DependenceInfo DI(F, &AR.AA, &AR.SE, &AR.LI);
+ return std::make_unique<DataDependenceGraph>(L, AR.LI, DI);
+}
+AnalysisKey DDGAnalysis::Key;
+
+PreservedAnalyses DDGAnalysisPrinterPass::run(Loop &L, LoopAnalysisManager &AM,
+ LoopStandardAnalysisResults &AR,
+ LPMUpdater &U) {
+ OS << "'DDG' for loop '" << L.getHeader()->getName() << "':\n";
+ OS << *AM.getResult<DDGAnalysis>(L, AR);
+ return PreservedAnalyses::all();
+}