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763 lines
27 KiB
763 lines
27 KiB
//===- CallGraphSCCPass.cpp - Pass that operates BU on call graph ---------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements the CallGraphSCCPass class, which is used for passes
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// which are implemented as bottom-up traversals on the call graph. Because
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// there may be cycles in the call graph, passes of this type operate on the
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// call-graph in SCC order: that is, they process function bottom-up, except for
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// recursive functions, which they process all at once.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/Analysis/CallGraphSCCPass.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/SCCIterator.h"
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#include "llvm/ADT/Statistic.h"
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#include "llvm/Analysis/CallGraph.h"
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#include "llvm/IR/AbstractCallSite.h"
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#include "llvm/IR/Function.h"
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#include "llvm/IR/Intrinsics.h"
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#include "llvm/IR/LLVMContext.h"
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#include "llvm/IR/LegacyPassManagers.h"
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#include "llvm/IR/Module.h"
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#include "llvm/IR/OptBisect.h"
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#include "llvm/IR/PassTimingInfo.h"
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#include "llvm/IR/PrintPasses.h"
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#include "llvm/IR/StructuralHash.h"
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#include "llvm/Pass.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/Timer.h"
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#include "llvm/Support/raw_ostream.h"
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#include <cassert>
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#include <string>
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#include <utility>
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#include <vector>
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using namespace llvm;
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#define DEBUG_TYPE "cgscc-passmgr"
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cl::opt<unsigned> MaxDevirtIterations("max-devirt-iterations", cl::ReallyHidden,
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cl::init(4));
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STATISTIC(MaxSCCIterations, "Maximum CGSCCPassMgr iterations on one SCC");
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//===----------------------------------------------------------------------===//
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// CGPassManager
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//
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/// CGPassManager manages FPPassManagers and CallGraphSCCPasses.
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namespace {
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class CGPassManager : public ModulePass, public PMDataManager {
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public:
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static char ID;
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explicit CGPassManager() : ModulePass(ID), PMDataManager() {}
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/// Execute all of the passes scheduled for execution. Keep track of
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/// whether any of the passes modifies the module, and if so, return true.
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bool runOnModule(Module &M) override;
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using ModulePass::doInitialization;
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using ModulePass::doFinalization;
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bool doInitialization(CallGraph &CG);
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bool doFinalization(CallGraph &CG);
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/// Pass Manager itself does not invalidate any analysis info.
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void getAnalysisUsage(AnalysisUsage &Info) const override {
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// CGPassManager walks SCC and it needs CallGraph.
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Info.addRequired<CallGraphWrapperPass>();
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Info.setPreservesAll();
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}
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StringRef getPassName() const override { return "CallGraph Pass Manager"; }
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PMDataManager *getAsPMDataManager() override { return this; }
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Pass *getAsPass() override { return this; }
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// Print passes managed by this manager
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void dumpPassStructure(unsigned Offset) override {
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errs().indent(Offset*2) << "Call Graph SCC Pass Manager\n";
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for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
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Pass *P = getContainedPass(Index);
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P->dumpPassStructure(Offset + 1);
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dumpLastUses(P, Offset+1);
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}
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}
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Pass *getContainedPass(unsigned N) {
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assert(N < PassVector.size() && "Pass number out of range!");
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return static_cast<Pass *>(PassVector[N]);
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}
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PassManagerType getPassManagerType() const override {
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return PMT_CallGraphPassManager;
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}
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private:
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bool RunAllPassesOnSCC(CallGraphSCC &CurSCC, CallGraph &CG,
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bool &DevirtualizedCall);
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bool RunPassOnSCC(Pass *P, CallGraphSCC &CurSCC,
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CallGraph &CG, bool &CallGraphUpToDate,
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bool &DevirtualizedCall);
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bool RefreshCallGraph(const CallGraphSCC &CurSCC, CallGraph &CG,
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bool IsCheckingMode);
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};
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} // end anonymous namespace.
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char CGPassManager::ID = 0;
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bool CGPassManager::RunPassOnSCC(Pass *P, CallGraphSCC &CurSCC,
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CallGraph &CG, bool &CallGraphUpToDate,
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bool &DevirtualizedCall) {
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bool Changed = false;
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PMDataManager *PM = P->getAsPMDataManager();
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Module &M = CG.getModule();
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if (!PM) {
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CallGraphSCCPass *CGSP = (CallGraphSCCPass *)P;
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if (!CallGraphUpToDate) {
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DevirtualizedCall |= RefreshCallGraph(CurSCC, CG, false);
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CallGraphUpToDate = true;
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}
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{
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unsigned InstrCount, SCCCount = 0;
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StringMap<std::pair<unsigned, unsigned>> FunctionToInstrCount;
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bool EmitICRemark = M.shouldEmitInstrCountChangedRemark();
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TimeRegion PassTimer(getPassTimer(CGSP));
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if (EmitICRemark)
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InstrCount = initSizeRemarkInfo(M, FunctionToInstrCount);
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Changed = CGSP->runOnSCC(CurSCC);
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if (EmitICRemark) {
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// FIXME: Add getInstructionCount to CallGraphSCC.
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SCCCount = M.getInstructionCount();
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// Is there a difference in the number of instructions in the module?
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if (SCCCount != InstrCount) {
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// Yep. Emit a remark and update InstrCount.
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int64_t Delta =
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static_cast<int64_t>(SCCCount) - static_cast<int64_t>(InstrCount);
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emitInstrCountChangedRemark(P, M, Delta, InstrCount,
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FunctionToInstrCount);
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InstrCount = SCCCount;
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}
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}
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}
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// After the CGSCCPass is done, when assertions are enabled, use
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// RefreshCallGraph to verify that the callgraph was correctly updated.
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#ifndef NDEBUG
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if (Changed)
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RefreshCallGraph(CurSCC, CG, true);
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#endif
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return Changed;
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}
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assert(PM->getPassManagerType() == PMT_FunctionPassManager &&
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"Invalid CGPassManager member");
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FPPassManager *FPP = (FPPassManager*)P;
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// Run pass P on all functions in the current SCC.
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for (CallGraphNode *CGN : CurSCC) {
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if (Function *F = CGN->getFunction()) {
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dumpPassInfo(P, EXECUTION_MSG, ON_FUNCTION_MSG, F->getName());
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{
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TimeRegion PassTimer(getPassTimer(FPP));
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Changed |= FPP->runOnFunction(*F);
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}
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F->getContext().yield();
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}
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}
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// The function pass(es) modified the IR, they may have clobbered the
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// callgraph.
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if (Changed && CallGraphUpToDate) {
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LLVM_DEBUG(dbgs() << "CGSCCPASSMGR: Pass Dirtied SCC: " << P->getPassName()
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<< '\n');
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CallGraphUpToDate = false;
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}
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return Changed;
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}
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/// Scan the functions in the specified CFG and resync the
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/// callgraph with the call sites found in it. This is used after
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/// FunctionPasses have potentially munged the callgraph, and can be used after
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/// CallGraphSCC passes to verify that they correctly updated the callgraph.
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///
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/// This function returns true if it devirtualized an existing function call,
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/// meaning it turned an indirect call into a direct call. This happens when
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/// a function pass like GVN optimizes away stuff feeding the indirect call.
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/// This never happens in checking mode.
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bool CGPassManager::RefreshCallGraph(const CallGraphSCC &CurSCC, CallGraph &CG,
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bool CheckingMode) {
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DenseMap<Value *, CallGraphNode *> Calls;
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LLVM_DEBUG(dbgs() << "CGSCCPASSMGR: Refreshing SCC with " << CurSCC.size()
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<< " nodes:\n";
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for (CallGraphNode *CGN
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: CurSCC) CGN->dump(););
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bool MadeChange = false;
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bool DevirtualizedCall = false;
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// Scan all functions in the SCC.
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unsigned FunctionNo = 0;
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for (CallGraphSCC::iterator SCCIdx = CurSCC.begin(), E = CurSCC.end();
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SCCIdx != E; ++SCCIdx, ++FunctionNo) {
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CallGraphNode *CGN = *SCCIdx;
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Function *F = CGN->getFunction();
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if (!F || F->isDeclaration()) continue;
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// Walk the function body looking for call sites. Sync up the call sites in
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// CGN with those actually in the function.
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// Keep track of the number of direct and indirect calls that were
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// invalidated and removed.
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unsigned NumDirectRemoved = 0, NumIndirectRemoved = 0;
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CallGraphNode::iterator CGNEnd = CGN->end();
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auto RemoveAndCheckForDone = [&](CallGraphNode::iterator I) {
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// Just remove the edge from the set of callees, keep track of whether
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// I points to the last element of the vector.
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bool WasLast = I + 1 == CGNEnd;
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CGN->removeCallEdge(I);
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// If I pointed to the last element of the vector, we have to bail out:
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// iterator checking rejects comparisons of the resultant pointer with
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// end.
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if (WasLast)
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return true;
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CGNEnd = CGN->end();
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return false;
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};
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// Get the set of call sites currently in the function.
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for (CallGraphNode::iterator I = CGN->begin(); I != CGNEnd;) {
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// Delete "reference" call records that do not have call instruction. We
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// reinsert them as needed later. However, keep them in checking mode.
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if (!I->first) {
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if (CheckingMode) {
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++I;
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continue;
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}
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if (RemoveAndCheckForDone(I))
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break;
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continue;
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}
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// If this call site is null, then the function pass deleted the call
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// entirely and the WeakTrackingVH nulled it out.
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auto *Call = dyn_cast_or_null<CallBase>(*I->first);
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if (!Call ||
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// If we've already seen this call site, then the FunctionPass RAUW'd
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// one call with another, which resulted in two "uses" in the edge
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// list of the same call.
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Calls.count(Call) ||
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// If the call edge is not from a call or invoke, or it is a
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// instrinsic call, then the function pass RAUW'd a call with
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// another value. This can happen when constant folding happens
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// of well known functions etc.
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(Call->getCalledFunction() &&
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Call->getCalledFunction()->isIntrinsic() &&
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Intrinsic::isLeaf(Call->getCalledFunction()->getIntrinsicID()))) {
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assert(!CheckingMode &&
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"CallGraphSCCPass did not update the CallGraph correctly!");
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// If this was an indirect call site, count it.
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if (!I->second->getFunction())
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++NumIndirectRemoved;
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else
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++NumDirectRemoved;
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if (RemoveAndCheckForDone(I))
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break;
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continue;
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}
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assert(!Calls.count(Call) && "Call site occurs in node multiple times");
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if (Call) {
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Function *Callee = Call->getCalledFunction();
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// Ignore intrinsics because they're not really function calls.
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if (!Callee || !(Callee->isIntrinsic()))
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Calls.insert(std::make_pair(Call, I->second));
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}
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++I;
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}
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// Loop over all of the instructions in the function, getting the callsites.
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// Keep track of the number of direct/indirect calls added.
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unsigned NumDirectAdded = 0, NumIndirectAdded = 0;
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for (BasicBlock &BB : *F)
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for (Instruction &I : BB) {
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auto *Call = dyn_cast<CallBase>(&I);
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if (!Call)
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continue;
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Function *Callee = Call->getCalledFunction();
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if (Callee && Callee->isIntrinsic())
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continue;
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// If we are not in checking mode, insert potential callback calls as
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// references. This is not a requirement but helps to iterate over the
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// functions in the right order.
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if (!CheckingMode) {
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forEachCallbackFunction(*Call, [&](Function *CB) {
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CGN->addCalledFunction(nullptr, CG.getOrInsertFunction(CB));
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});
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}
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// If this call site already existed in the callgraph, just verify it
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// matches up to expectations and remove it from Calls.
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DenseMap<Value *, CallGraphNode *>::iterator ExistingIt =
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Calls.find(Call);
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if (ExistingIt != Calls.end()) {
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CallGraphNode *ExistingNode = ExistingIt->second;
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// Remove from Calls since we have now seen it.
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Calls.erase(ExistingIt);
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// Verify that the callee is right.
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if (ExistingNode->getFunction() == Call->getCalledFunction())
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continue;
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// If we are in checking mode, we are not allowed to actually mutate
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// the callgraph. If this is a case where we can infer that the
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// callgraph is less precise than it could be (e.g. an indirect call
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// site could be turned direct), don't reject it in checking mode, and
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// don't tweak it to be more precise.
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if (CheckingMode && Call->getCalledFunction() &&
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ExistingNode->getFunction() == nullptr)
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continue;
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assert(!CheckingMode &&
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"CallGraphSCCPass did not update the CallGraph correctly!");
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// If not, we either went from a direct call to indirect, indirect to
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// direct, or direct to different direct.
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CallGraphNode *CalleeNode;
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if (Function *Callee = Call->getCalledFunction()) {
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CalleeNode = CG.getOrInsertFunction(Callee);
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// Keep track of whether we turned an indirect call into a direct
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// one.
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if (!ExistingNode->getFunction()) {
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DevirtualizedCall = true;
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LLVM_DEBUG(dbgs() << " CGSCCPASSMGR: Devirtualized call to '"
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<< Callee->getName() << "'\n");
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}
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} else {
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CalleeNode = CG.getCallsExternalNode();
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}
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// Update the edge target in CGN.
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CGN->replaceCallEdge(*Call, *Call, CalleeNode);
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MadeChange = true;
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continue;
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}
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assert(!CheckingMode &&
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"CallGraphSCCPass did not update the CallGraph correctly!");
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// If the call site didn't exist in the CGN yet, add it.
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CallGraphNode *CalleeNode;
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if (Function *Callee = Call->getCalledFunction()) {
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CalleeNode = CG.getOrInsertFunction(Callee);
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++NumDirectAdded;
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} else {
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CalleeNode = CG.getCallsExternalNode();
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++NumIndirectAdded;
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}
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CGN->addCalledFunction(Call, CalleeNode);
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MadeChange = true;
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}
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// We scanned the old callgraph node, removing invalidated call sites and
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// then added back newly found call sites. One thing that can happen is
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// that an old indirect call site was deleted and replaced with a new direct
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// call. In this case, we have devirtualized a call, and CGSCCPM would like
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// to iteratively optimize the new code. Unfortunately, we don't really
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// have a great way to detect when this happens. As an approximation, we
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// just look at whether the number of indirect calls is reduced and the
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// number of direct calls is increased. There are tons of ways to fool this
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// (e.g. DCE'ing an indirect call and duplicating an unrelated block with a
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// direct call) but this is close enough.
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if (NumIndirectRemoved > NumIndirectAdded &&
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NumDirectRemoved < NumDirectAdded)
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DevirtualizedCall = true;
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// After scanning this function, if we still have entries in callsites, then
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// they are dangling pointers. WeakTrackingVH should save us for this, so
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// abort if
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// this happens.
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assert(Calls.empty() && "Dangling pointers found in call sites map");
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// Periodically do an explicit clear to remove tombstones when processing
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// large scc's.
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if ((FunctionNo & 15) == 15)
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Calls.clear();
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}
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LLVM_DEBUG(if (MadeChange) {
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dbgs() << "CGSCCPASSMGR: Refreshed SCC is now:\n";
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for (CallGraphNode *CGN : CurSCC)
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CGN->dump();
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if (DevirtualizedCall)
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dbgs() << "CGSCCPASSMGR: Refresh devirtualized a call!\n";
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} else {
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dbgs() << "CGSCCPASSMGR: SCC Refresh didn't change call graph.\n";
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});
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(void)MadeChange;
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return DevirtualizedCall;
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}
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/// Execute the body of the entire pass manager on the specified SCC.
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/// This keeps track of whether a function pass devirtualizes
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/// any calls and returns it in DevirtualizedCall.
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bool CGPassManager::RunAllPassesOnSCC(CallGraphSCC &CurSCC, CallGraph &CG,
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bool &DevirtualizedCall) {
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bool Changed = false;
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// Keep track of whether the callgraph is known to be up-to-date or not.
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// The CGSSC pass manager runs two types of passes:
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// CallGraphSCC Passes and other random function passes. Because other
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// random function passes are not CallGraph aware, they may clobber the
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// call graph by introducing new calls or deleting other ones. This flag
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// is set to false when we run a function pass so that we know to clean up
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// the callgraph when we need to run a CGSCCPass again.
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bool CallGraphUpToDate = true;
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// Run all passes on current SCC.
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for (unsigned PassNo = 0, e = getNumContainedPasses();
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PassNo != e; ++PassNo) {
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Pass *P = getContainedPass(PassNo);
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// If we're in -debug-pass=Executions mode, construct the SCC node list,
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// otherwise avoid constructing this string as it is expensive.
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if (isPassDebuggingExecutionsOrMore()) {
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std::string Functions;
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#ifndef NDEBUG
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raw_string_ostream OS(Functions);
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for (CallGraphSCC::iterator I = CurSCC.begin(), E = CurSCC.end();
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I != E; ++I) {
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if (I != CurSCC.begin()) OS << ", ";
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(*I)->print(OS);
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}
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OS.flush();
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#endif
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dumpPassInfo(P, EXECUTION_MSG, ON_CG_MSG, Functions);
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}
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dumpRequiredSet(P);
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initializeAnalysisImpl(P);
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#ifdef EXPENSIVE_CHECKS
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uint64_t RefHash = StructuralHash(CG.getModule());
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#endif
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// Actually run this pass on the current SCC.
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bool LocalChanged =
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RunPassOnSCC(P, CurSCC, CG, CallGraphUpToDate, DevirtualizedCall);
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Changed |= LocalChanged;
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#ifdef EXPENSIVE_CHECKS
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if (!LocalChanged && (RefHash != StructuralHash(CG.getModule()))) {
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llvm::errs() << "Pass modifies its input and doesn't report it: "
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<< P->getPassName() << "\n";
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llvm_unreachable("Pass modifies its input and doesn't report it");
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}
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#endif
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if (LocalChanged)
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dumpPassInfo(P, MODIFICATION_MSG, ON_CG_MSG, "");
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dumpPreservedSet(P);
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verifyPreservedAnalysis(P);
|
|
if (LocalChanged)
|
|
removeNotPreservedAnalysis(P);
|
|
recordAvailableAnalysis(P);
|
|
removeDeadPasses(P, "", ON_CG_MSG);
|
|
}
|
|
|
|
// If the callgraph was left out of date (because the last pass run was a
|
|
// functionpass), refresh it before we move on to the next SCC.
|
|
if (!CallGraphUpToDate)
|
|
DevirtualizedCall |= RefreshCallGraph(CurSCC, CG, false);
|
|
return Changed;
|
|
}
|
|
|
|
/// Execute all of the passes scheduled for execution. Keep track of
|
|
/// whether any of the passes modifies the module, and if so, return true.
|
|
bool CGPassManager::runOnModule(Module &M) {
|
|
CallGraph &CG = getAnalysis<CallGraphWrapperPass>().getCallGraph();
|
|
bool Changed = doInitialization(CG);
|
|
|
|
// Walk the callgraph in bottom-up SCC order.
|
|
scc_iterator<CallGraph*> CGI = scc_begin(&CG);
|
|
|
|
CallGraphSCC CurSCC(CG, &CGI);
|
|
while (!CGI.isAtEnd()) {
|
|
// Copy the current SCC and increment past it so that the pass can hack
|
|
// on the SCC if it wants to without invalidating our iterator.
|
|
const std::vector<CallGraphNode *> &NodeVec = *CGI;
|
|
CurSCC.initialize(NodeVec);
|
|
++CGI;
|
|
|
|
// At the top level, we run all the passes in this pass manager on the
|
|
// functions in this SCC. However, we support iterative compilation in the
|
|
// case where a function pass devirtualizes a call to a function. For
|
|
// example, it is very common for a function pass (often GVN or instcombine)
|
|
// to eliminate the addressing that feeds into a call. With that improved
|
|
// information, we would like the call to be an inline candidate, infer
|
|
// mod-ref information etc.
|
|
//
|
|
// Because of this, we allow iteration up to a specified iteration count.
|
|
// This only happens in the case of a devirtualized call, so we only burn
|
|
// compile time in the case that we're making progress. We also have a hard
|
|
// iteration count limit in case there is crazy code.
|
|
unsigned Iteration = 0;
|
|
bool DevirtualizedCall = false;
|
|
do {
|
|
LLVM_DEBUG(if (Iteration) dbgs()
|
|
<< " SCCPASSMGR: Re-visiting SCC, iteration #" << Iteration
|
|
<< '\n');
|
|
DevirtualizedCall = false;
|
|
Changed |= RunAllPassesOnSCC(CurSCC, CG, DevirtualizedCall);
|
|
} while (Iteration++ < MaxDevirtIterations && DevirtualizedCall);
|
|
|
|
if (DevirtualizedCall)
|
|
LLVM_DEBUG(dbgs() << " CGSCCPASSMGR: Stopped iteration after "
|
|
<< Iteration
|
|
<< " times, due to -max-devirt-iterations\n");
|
|
|
|
MaxSCCIterations.updateMax(Iteration);
|
|
}
|
|
Changed |= doFinalization(CG);
|
|
return Changed;
|
|
}
|
|
|
|
/// Initialize CG
|
|
bool CGPassManager::doInitialization(CallGraph &CG) {
|
|
bool Changed = false;
|
|
for (unsigned i = 0, e = getNumContainedPasses(); i != e; ++i) {
|
|
if (PMDataManager *PM = getContainedPass(i)->getAsPMDataManager()) {
|
|
assert(PM->getPassManagerType() == PMT_FunctionPassManager &&
|
|
"Invalid CGPassManager member");
|
|
Changed |= ((FPPassManager*)PM)->doInitialization(CG.getModule());
|
|
} else {
|
|
Changed |= ((CallGraphSCCPass*)getContainedPass(i))->doInitialization(CG);
|
|
}
|
|
}
|
|
return Changed;
|
|
}
|
|
|
|
/// Finalize CG
|
|
bool CGPassManager::doFinalization(CallGraph &CG) {
|
|
bool Changed = false;
|
|
for (unsigned i = 0, e = getNumContainedPasses(); i != e; ++i) {
|
|
if (PMDataManager *PM = getContainedPass(i)->getAsPMDataManager()) {
|
|
assert(PM->getPassManagerType() == PMT_FunctionPassManager &&
|
|
"Invalid CGPassManager member");
|
|
Changed |= ((FPPassManager*)PM)->doFinalization(CG.getModule());
|
|
} else {
|
|
Changed |= ((CallGraphSCCPass*)getContainedPass(i))->doFinalization(CG);
|
|
}
|
|
}
|
|
return Changed;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// CallGraphSCC Implementation
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
/// This informs the SCC and the pass manager that the specified
|
|
/// Old node has been deleted, and New is to be used in its place.
|
|
void CallGraphSCC::ReplaceNode(CallGraphNode *Old, CallGraphNode *New) {
|
|
assert(Old != New && "Should not replace node with self");
|
|
for (unsigned i = 0; ; ++i) {
|
|
assert(i != Nodes.size() && "Node not in SCC");
|
|
if (Nodes[i] != Old) continue;
|
|
if (New)
|
|
Nodes[i] = New;
|
|
else
|
|
Nodes.erase(Nodes.begin() + i);
|
|
break;
|
|
}
|
|
|
|
// Update the active scc_iterator so that it doesn't contain dangling
|
|
// pointers to the old CallGraphNode.
|
|
scc_iterator<CallGraph*> *CGI = (scc_iterator<CallGraph*>*)Context;
|
|
CGI->ReplaceNode(Old, New);
|
|
}
|
|
|
|
void CallGraphSCC::DeleteNode(CallGraphNode *Old) {
|
|
ReplaceNode(Old, /*New=*/nullptr);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// CallGraphSCCPass Implementation
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
/// Assign pass manager to manage this pass.
|
|
void CallGraphSCCPass::assignPassManager(PMStack &PMS,
|
|
PassManagerType PreferredType) {
|
|
// Find CGPassManager
|
|
while (!PMS.empty() &&
|
|
PMS.top()->getPassManagerType() > PMT_CallGraphPassManager)
|
|
PMS.pop();
|
|
|
|
assert(!PMS.empty() && "Unable to handle Call Graph Pass");
|
|
CGPassManager *CGP;
|
|
|
|
if (PMS.top()->getPassManagerType() == PMT_CallGraphPassManager)
|
|
CGP = (CGPassManager*)PMS.top();
|
|
else {
|
|
// Create new Call Graph SCC Pass Manager if it does not exist.
|
|
assert(!PMS.empty() && "Unable to create Call Graph Pass Manager");
|
|
PMDataManager *PMD = PMS.top();
|
|
|
|
// [1] Create new Call Graph Pass Manager
|
|
CGP = new CGPassManager();
|
|
|
|
// [2] Set up new manager's top level manager
|
|
PMTopLevelManager *TPM = PMD->getTopLevelManager();
|
|
TPM->addIndirectPassManager(CGP);
|
|
|
|
// [3] Assign manager to manage this new manager. This may create
|
|
// and push new managers into PMS
|
|
Pass *P = CGP;
|
|
TPM->schedulePass(P);
|
|
|
|
// [4] Push new manager into PMS
|
|
PMS.push(CGP);
|
|
}
|
|
|
|
CGP->add(this);
|
|
}
|
|
|
|
/// For this class, we declare that we require and preserve the call graph.
|
|
/// If the derived class implements this method, it should
|
|
/// always explicitly call the implementation here.
|
|
void CallGraphSCCPass::getAnalysisUsage(AnalysisUsage &AU) const {
|
|
AU.addRequired<CallGraphWrapperPass>();
|
|
AU.addPreserved<CallGraphWrapperPass>();
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// PrintCallGraphPass Implementation
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace {
|
|
|
|
/// PrintCallGraphPass - Print a Module corresponding to a call graph.
|
|
///
|
|
class PrintCallGraphPass : public CallGraphSCCPass {
|
|
std::string Banner;
|
|
raw_ostream &OS; // raw_ostream to print on.
|
|
|
|
public:
|
|
static char ID;
|
|
|
|
PrintCallGraphPass(const std::string &B, raw_ostream &OS)
|
|
: CallGraphSCCPass(ID), Banner(B), OS(OS) {}
|
|
|
|
void getAnalysisUsage(AnalysisUsage &AU) const override {
|
|
AU.setPreservesAll();
|
|
}
|
|
|
|
bool runOnSCC(CallGraphSCC &SCC) override {
|
|
bool BannerPrinted = false;
|
|
auto PrintBannerOnce = [&]() {
|
|
if (BannerPrinted)
|
|
return;
|
|
OS << Banner;
|
|
BannerPrinted = true;
|
|
};
|
|
|
|
bool NeedModule = llvm::forcePrintModuleIR();
|
|
if (isFunctionInPrintList("*") && NeedModule) {
|
|
PrintBannerOnce();
|
|
OS << "\n";
|
|
SCC.getCallGraph().getModule().print(OS, nullptr);
|
|
return false;
|
|
}
|
|
bool FoundFunction = false;
|
|
for (CallGraphNode *CGN : SCC) {
|
|
if (Function *F = CGN->getFunction()) {
|
|
if (!F->isDeclaration() && isFunctionInPrintList(F->getName())) {
|
|
FoundFunction = true;
|
|
if (!NeedModule) {
|
|
PrintBannerOnce();
|
|
F->print(OS);
|
|
}
|
|
}
|
|
} else if (isFunctionInPrintList("*")) {
|
|
PrintBannerOnce();
|
|
OS << "\nPrinting <null> Function\n";
|
|
}
|
|
}
|
|
if (NeedModule && FoundFunction) {
|
|
PrintBannerOnce();
|
|
OS << "\n";
|
|
SCC.getCallGraph().getModule().print(OS, nullptr);
|
|
}
|
|
return false;
|
|
}
|
|
|
|
StringRef getPassName() const override { return "Print CallGraph IR"; }
|
|
};
|
|
|
|
} // end anonymous namespace.
|
|
|
|
char PrintCallGraphPass::ID = 0;
|
|
|
|
Pass *CallGraphSCCPass::createPrinterPass(raw_ostream &OS,
|
|
const std::string &Banner) const {
|
|
return new PrintCallGraphPass(Banner, OS);
|
|
}
|
|
|
|
static std::string getDescription(const CallGraphSCC &SCC) {
|
|
std::string Desc = "SCC (";
|
|
bool First = true;
|
|
for (CallGraphNode *CGN : SCC) {
|
|
if (First)
|
|
First = false;
|
|
else
|
|
Desc += ", ";
|
|
Function *F = CGN->getFunction();
|
|
if (F)
|
|
Desc += F->getName();
|
|
else
|
|
Desc += "<<null function>>";
|
|
}
|
|
Desc += ")";
|
|
return Desc;
|
|
}
|
|
|
|
bool CallGraphSCCPass::skipSCC(CallGraphSCC &SCC) const {
|
|
OptPassGate &Gate =
|
|
SCC.getCallGraph().getModule().getContext().getOptPassGate();
|
|
return Gate.isEnabled() && !Gate.shouldRunPass(this, getDescription(SCC));
|
|
}
|
|
|
|
char DummyCGSCCPass::ID = 0;
|
|
|
|
INITIALIZE_PASS(DummyCGSCCPass, "DummyCGSCCPass", "DummyCGSCCPass", false,
|
|
false)
|