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https://github.com/RPCS3/llvm-mirror.git
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0c7ba752d1
Summary: I found that there currently isn't a way to invoke exportToDot from the command line for a per-module summary index, and therefore no testing of that case. Add an internal option and use it to test dumping of per module summary indexes. In particular, I am looking at fixing the limitation that causes the aliasee GUID in the per-module summary to be 0, and want to be able to test that change. Reviewers: evgeny777 Subscribers: mehdi_amini, inglorion, eraman, steven_wu, dexonsmith, llvm-commits Differential Revision: https://reviews.llvm.org/D57206 llvm-svn: 352441
701 lines
28 KiB
C++
701 lines
28 KiB
C++
//===- ModuleSummaryAnalysis.cpp - Module summary index builder -----------===//
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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 pass builds a ModuleSummaryIndex object for the module, to be written
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// to bitcode or LLVM assembly.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/Analysis/ModuleSummaryAnalysis.h"
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#include "llvm/ADT/ArrayRef.h"
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#include "llvm/ADT/DenseSet.h"
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#include "llvm/ADT/MapVector.h"
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#include "llvm/ADT/STLExtras.h"
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#include "llvm/ADT/SetVector.h"
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#include "llvm/ADT/SmallPtrSet.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/ADT/StringRef.h"
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#include "llvm/Analysis/BlockFrequencyInfo.h"
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#include "llvm/Analysis/BranchProbabilityInfo.h"
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#include "llvm/Analysis/IndirectCallPromotionAnalysis.h"
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#include "llvm/Analysis/LoopInfo.h"
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#include "llvm/Analysis/ProfileSummaryInfo.h"
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#include "llvm/Analysis/TypeMetadataUtils.h"
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#include "llvm/IR/Attributes.h"
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#include "llvm/IR/BasicBlock.h"
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#include "llvm/IR/CallSite.h"
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#include "llvm/IR/Constant.h"
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#include "llvm/IR/Constants.h"
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#include "llvm/IR/Dominators.h"
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#include "llvm/IR/Function.h"
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#include "llvm/IR/GlobalAlias.h"
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#include "llvm/IR/GlobalValue.h"
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#include "llvm/IR/GlobalVariable.h"
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#include "llvm/IR/Instructions.h"
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#include "llvm/IR/IntrinsicInst.h"
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#include "llvm/IR/Intrinsics.h"
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#include "llvm/IR/Metadata.h"
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#include "llvm/IR/Module.h"
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#include "llvm/IR/ModuleSummaryIndex.h"
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#include "llvm/IR/Use.h"
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#include "llvm/IR/User.h"
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#include "llvm/Object/ModuleSymbolTable.h"
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#include "llvm/Object/SymbolicFile.h"
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#include "llvm/Pass.h"
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#include "llvm/Support/Casting.h"
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#include "llvm/Support/CommandLine.h"
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#include <algorithm>
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#include <cassert>
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#include <cstdint>
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#include <vector>
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using namespace llvm;
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#define DEBUG_TYPE "module-summary-analysis"
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// Option to force edges cold which will block importing when the
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// -import-cold-multiplier is set to 0. Useful for debugging.
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FunctionSummary::ForceSummaryHotnessType ForceSummaryEdgesCold =
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FunctionSummary::FSHT_None;
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cl::opt<FunctionSummary::ForceSummaryHotnessType, true> FSEC(
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"force-summary-edges-cold", cl::Hidden, cl::location(ForceSummaryEdgesCold),
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cl::desc("Force all edges in the function summary to cold"),
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cl::values(clEnumValN(FunctionSummary::FSHT_None, "none", "None."),
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clEnumValN(FunctionSummary::FSHT_AllNonCritical,
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"all-non-critical", "All non-critical edges."),
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clEnumValN(FunctionSummary::FSHT_All, "all", "All edges.")));
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cl::opt<std::string> ModuleSummaryDotFile(
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"module-summary-dot-file", cl::init(""), cl::Hidden,
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cl::value_desc("filename"),
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cl::desc("File to emit dot graph of new summary into."));
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// Walk through the operands of a given User via worklist iteration and populate
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// the set of GlobalValue references encountered. Invoked either on an
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// Instruction or a GlobalVariable (which walks its initializer).
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// Return true if any of the operands contains blockaddress. This is important
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// to know when computing summary for global var, because if global variable
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// references basic block address we can't import it separately from function
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// containing that basic block. For simplicity we currently don't import such
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// global vars at all. When importing function we aren't interested if any
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// instruction in it takes an address of any basic block, because instruction
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// can only take an address of basic block located in the same function.
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static bool findRefEdges(ModuleSummaryIndex &Index, const User *CurUser,
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SetVector<ValueInfo> &RefEdges,
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SmallPtrSet<const User *, 8> &Visited) {
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bool HasBlockAddress = false;
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SmallVector<const User *, 32> Worklist;
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Worklist.push_back(CurUser);
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while (!Worklist.empty()) {
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const User *U = Worklist.pop_back_val();
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if (!Visited.insert(U).second)
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continue;
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ImmutableCallSite CS(U);
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for (const auto &OI : U->operands()) {
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const User *Operand = dyn_cast<User>(OI);
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if (!Operand)
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continue;
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if (isa<BlockAddress>(Operand)) {
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HasBlockAddress = true;
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continue;
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}
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if (auto *GV = dyn_cast<GlobalValue>(Operand)) {
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// We have a reference to a global value. This should be added to
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// the reference set unless it is a callee. Callees are handled
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// specially by WriteFunction and are added to a separate list.
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if (!(CS && CS.isCallee(&OI)))
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RefEdges.insert(Index.getOrInsertValueInfo(GV));
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continue;
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}
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Worklist.push_back(Operand);
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}
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}
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return HasBlockAddress;
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}
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static CalleeInfo::HotnessType getHotness(uint64_t ProfileCount,
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ProfileSummaryInfo *PSI) {
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if (!PSI)
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return CalleeInfo::HotnessType::Unknown;
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if (PSI->isHotCount(ProfileCount))
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return CalleeInfo::HotnessType::Hot;
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if (PSI->isColdCount(ProfileCount))
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return CalleeInfo::HotnessType::Cold;
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return CalleeInfo::HotnessType::None;
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}
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static bool isNonRenamableLocal(const GlobalValue &GV) {
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return GV.hasSection() && GV.hasLocalLinkage();
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}
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/// Determine whether this call has all constant integer arguments (excluding
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/// "this") and summarize it to VCalls or ConstVCalls as appropriate.
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static void addVCallToSet(DevirtCallSite Call, GlobalValue::GUID Guid,
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SetVector<FunctionSummary::VFuncId> &VCalls,
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SetVector<FunctionSummary::ConstVCall> &ConstVCalls) {
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std::vector<uint64_t> Args;
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// Start from the second argument to skip the "this" pointer.
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for (auto &Arg : make_range(Call.CS.arg_begin() + 1, Call.CS.arg_end())) {
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auto *CI = dyn_cast<ConstantInt>(Arg);
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if (!CI || CI->getBitWidth() > 64) {
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VCalls.insert({Guid, Call.Offset});
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return;
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}
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Args.push_back(CI->getZExtValue());
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}
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ConstVCalls.insert({{Guid, Call.Offset}, std::move(Args)});
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}
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/// If this intrinsic call requires that we add information to the function
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/// summary, do so via the non-constant reference arguments.
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static void addIntrinsicToSummary(
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const CallInst *CI, SetVector<GlobalValue::GUID> &TypeTests,
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SetVector<FunctionSummary::VFuncId> &TypeTestAssumeVCalls,
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SetVector<FunctionSummary::VFuncId> &TypeCheckedLoadVCalls,
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SetVector<FunctionSummary::ConstVCall> &TypeTestAssumeConstVCalls,
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SetVector<FunctionSummary::ConstVCall> &TypeCheckedLoadConstVCalls,
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DominatorTree &DT) {
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switch (CI->getCalledFunction()->getIntrinsicID()) {
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case Intrinsic::type_test: {
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auto *TypeMDVal = cast<MetadataAsValue>(CI->getArgOperand(1));
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auto *TypeId = dyn_cast<MDString>(TypeMDVal->getMetadata());
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if (!TypeId)
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break;
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GlobalValue::GUID Guid = GlobalValue::getGUID(TypeId->getString());
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// Produce a summary from type.test intrinsics. We only summarize type.test
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// intrinsics that are used other than by an llvm.assume intrinsic.
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// Intrinsics that are assumed are relevant only to the devirtualization
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// pass, not the type test lowering pass.
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bool HasNonAssumeUses = llvm::any_of(CI->uses(), [](const Use &CIU) {
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auto *AssumeCI = dyn_cast<CallInst>(CIU.getUser());
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if (!AssumeCI)
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return true;
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Function *F = AssumeCI->getCalledFunction();
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return !F || F->getIntrinsicID() != Intrinsic::assume;
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});
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if (HasNonAssumeUses)
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TypeTests.insert(Guid);
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SmallVector<DevirtCallSite, 4> DevirtCalls;
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SmallVector<CallInst *, 4> Assumes;
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findDevirtualizableCallsForTypeTest(DevirtCalls, Assumes, CI, DT);
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for (auto &Call : DevirtCalls)
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addVCallToSet(Call, Guid, TypeTestAssumeVCalls,
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TypeTestAssumeConstVCalls);
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break;
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}
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case Intrinsic::type_checked_load: {
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auto *TypeMDVal = cast<MetadataAsValue>(CI->getArgOperand(2));
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auto *TypeId = dyn_cast<MDString>(TypeMDVal->getMetadata());
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if (!TypeId)
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break;
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GlobalValue::GUID Guid = GlobalValue::getGUID(TypeId->getString());
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SmallVector<DevirtCallSite, 4> DevirtCalls;
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SmallVector<Instruction *, 4> LoadedPtrs;
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SmallVector<Instruction *, 4> Preds;
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bool HasNonCallUses = false;
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findDevirtualizableCallsForTypeCheckedLoad(DevirtCalls, LoadedPtrs, Preds,
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HasNonCallUses, CI, DT);
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// Any non-call uses of the result of llvm.type.checked.load will
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// prevent us from optimizing away the llvm.type.test.
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if (HasNonCallUses)
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TypeTests.insert(Guid);
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for (auto &Call : DevirtCalls)
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addVCallToSet(Call, Guid, TypeCheckedLoadVCalls,
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TypeCheckedLoadConstVCalls);
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break;
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}
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default:
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break;
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}
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}
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static bool isNonVolatileLoad(const Instruction *I) {
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if (const auto *LI = dyn_cast<LoadInst>(I))
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return !LI->isVolatile();
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return false;
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}
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static void computeFunctionSummary(ModuleSummaryIndex &Index, const Module &M,
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const Function &F, BlockFrequencyInfo *BFI,
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ProfileSummaryInfo *PSI, DominatorTree &DT,
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bool HasLocalsInUsedOrAsm,
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DenseSet<GlobalValue::GUID> &CantBePromoted,
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bool IsThinLTO) {
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// Summary not currently supported for anonymous functions, they should
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// have been named.
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assert(F.hasName());
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unsigned NumInsts = 0;
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// Map from callee ValueId to profile count. Used to accumulate profile
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// counts for all static calls to a given callee.
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MapVector<ValueInfo, CalleeInfo> CallGraphEdges;
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SetVector<ValueInfo> RefEdges;
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SetVector<GlobalValue::GUID> TypeTests;
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SetVector<FunctionSummary::VFuncId> TypeTestAssumeVCalls,
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TypeCheckedLoadVCalls;
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SetVector<FunctionSummary::ConstVCall> TypeTestAssumeConstVCalls,
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TypeCheckedLoadConstVCalls;
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ICallPromotionAnalysis ICallAnalysis;
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SmallPtrSet<const User *, 8> Visited;
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// Add personality function, prefix data and prologue data to function's ref
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// list.
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findRefEdges(Index, &F, RefEdges, Visited);
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std::vector<const Instruction *> NonVolatileLoads;
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bool HasInlineAsmMaybeReferencingInternal = false;
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for (const BasicBlock &BB : F)
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for (const Instruction &I : BB) {
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if (isa<DbgInfoIntrinsic>(I))
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continue;
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++NumInsts;
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if (isNonVolatileLoad(&I)) {
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// Postpone processing of non-volatile load instructions
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// See comments below
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Visited.insert(&I);
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NonVolatileLoads.push_back(&I);
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continue;
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}
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findRefEdges(Index, &I, RefEdges, Visited);
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auto CS = ImmutableCallSite(&I);
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if (!CS)
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continue;
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const auto *CI = dyn_cast<CallInst>(&I);
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// Since we don't know exactly which local values are referenced in inline
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// assembly, conservatively mark the function as possibly referencing
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// a local value from inline assembly to ensure we don't export a
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// reference (which would require renaming and promotion of the
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// referenced value).
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if (HasLocalsInUsedOrAsm && CI && CI->isInlineAsm())
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HasInlineAsmMaybeReferencingInternal = true;
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auto *CalledValue = CS.getCalledValue();
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auto *CalledFunction = CS.getCalledFunction();
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if (CalledValue && !CalledFunction) {
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CalledValue = CalledValue->stripPointerCastsNoFollowAliases();
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// Stripping pointer casts can reveal a called function.
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CalledFunction = dyn_cast<Function>(CalledValue);
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}
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// Check if this is an alias to a function. If so, get the
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// called aliasee for the checks below.
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if (auto *GA = dyn_cast<GlobalAlias>(CalledValue)) {
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assert(!CalledFunction && "Expected null called function in callsite for alias");
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CalledFunction = dyn_cast<Function>(GA->getBaseObject());
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}
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// Check if this is a direct call to a known function or a known
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// intrinsic, or an indirect call with profile data.
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if (CalledFunction) {
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if (CI && CalledFunction->isIntrinsic()) {
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addIntrinsicToSummary(
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CI, TypeTests, TypeTestAssumeVCalls, TypeCheckedLoadVCalls,
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TypeTestAssumeConstVCalls, TypeCheckedLoadConstVCalls, DT);
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continue;
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}
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// We should have named any anonymous globals
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assert(CalledFunction->hasName());
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auto ScaledCount = PSI->getProfileCount(&I, BFI);
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auto Hotness = ScaledCount ? getHotness(ScaledCount.getValue(), PSI)
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: CalleeInfo::HotnessType::Unknown;
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if (ForceSummaryEdgesCold != FunctionSummary::FSHT_None)
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Hotness = CalleeInfo::HotnessType::Cold;
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// Use the original CalledValue, in case it was an alias. We want
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// to record the call edge to the alias in that case. Eventually
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// an alias summary will be created to associate the alias and
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// aliasee.
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auto &ValueInfo = CallGraphEdges[Index.getOrInsertValueInfo(
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cast<GlobalValue>(CalledValue))];
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ValueInfo.updateHotness(Hotness);
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// Add the relative block frequency to CalleeInfo if there is no profile
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// information.
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if (BFI != nullptr && Hotness == CalleeInfo::HotnessType::Unknown) {
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uint64_t BBFreq = BFI->getBlockFreq(&BB).getFrequency();
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uint64_t EntryFreq = BFI->getEntryFreq();
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ValueInfo.updateRelBlockFreq(BBFreq, EntryFreq);
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}
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} else {
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// Skip inline assembly calls.
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if (CI && CI->isInlineAsm())
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continue;
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// Skip direct calls.
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if (!CalledValue || isa<Constant>(CalledValue))
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continue;
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// Check if the instruction has a callees metadata. If so, add callees
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// to CallGraphEdges to reflect the references from the metadata, and
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// to enable importing for subsequent indirect call promotion and
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// inlining.
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if (auto *MD = I.getMetadata(LLVMContext::MD_callees)) {
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for (auto &Op : MD->operands()) {
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Function *Callee = mdconst::extract_or_null<Function>(Op);
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if (Callee)
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CallGraphEdges[Index.getOrInsertValueInfo(Callee)];
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}
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}
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uint32_t NumVals, NumCandidates;
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uint64_t TotalCount;
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auto CandidateProfileData =
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ICallAnalysis.getPromotionCandidatesForInstruction(
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&I, NumVals, TotalCount, NumCandidates);
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for (auto &Candidate : CandidateProfileData)
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CallGraphEdges[Index.getOrInsertValueInfo(Candidate.Value)]
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.updateHotness(getHotness(Candidate.Count, PSI));
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}
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}
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// By now we processed all instructions in a function, except
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// non-volatile loads. All new refs we add in a loop below
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// are obviously constant. All constant refs are grouped in the
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// end of RefEdges vector, so we can use a single integer value
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// to identify them.
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unsigned RefCnt = RefEdges.size();
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for (const Instruction *I : NonVolatileLoads) {
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Visited.erase(I);
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findRefEdges(Index, I, RefEdges, Visited);
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}
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std::vector<ValueInfo> Refs = RefEdges.takeVector();
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// Regular LTO module doesn't participate in ThinLTO import,
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// so no reference from it can be readonly, since this would
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// require importing variable as local copy
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if (IsThinLTO)
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for (; RefCnt < Refs.size(); ++RefCnt)
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Refs[RefCnt].setReadOnly();
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// Explicit add hot edges to enforce importing for designated GUIDs for
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// sample PGO, to enable the same inlines as the profiled optimized binary.
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for (auto &I : F.getImportGUIDs())
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CallGraphEdges[Index.getOrInsertValueInfo(I)].updateHotness(
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ForceSummaryEdgesCold == FunctionSummary::FSHT_All
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? CalleeInfo::HotnessType::Cold
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: CalleeInfo::HotnessType::Critical);
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bool NonRenamableLocal = isNonRenamableLocal(F);
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bool NotEligibleForImport =
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NonRenamableLocal || HasInlineAsmMaybeReferencingInternal;
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GlobalValueSummary::GVFlags Flags(F.getLinkage(), NotEligibleForImport,
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/* Live = */ false, F.isDSOLocal());
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FunctionSummary::FFlags FunFlags{
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F.hasFnAttribute(Attribute::ReadNone),
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F.hasFnAttribute(Attribute::ReadOnly),
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F.hasFnAttribute(Attribute::NoRecurse), F.returnDoesNotAlias(),
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// FIXME: refactor this to use the same code that inliner is using.
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// Don't try to import functions with noinline attribute.
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F.getAttributes().hasFnAttribute(Attribute::NoInline)};
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auto FuncSummary = llvm::make_unique<FunctionSummary>(
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Flags, NumInsts, FunFlags, /*EntryCount=*/0, std::move(Refs),
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CallGraphEdges.takeVector(), TypeTests.takeVector(),
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TypeTestAssumeVCalls.takeVector(), TypeCheckedLoadVCalls.takeVector(),
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TypeTestAssumeConstVCalls.takeVector(),
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TypeCheckedLoadConstVCalls.takeVector());
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if (NonRenamableLocal)
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CantBePromoted.insert(F.getGUID());
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Index.addGlobalValueSummary(F, std::move(FuncSummary));
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}
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static void
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computeVariableSummary(ModuleSummaryIndex &Index, const GlobalVariable &V,
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DenseSet<GlobalValue::GUID> &CantBePromoted) {
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SetVector<ValueInfo> RefEdges;
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SmallPtrSet<const User *, 8> Visited;
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bool HasBlockAddress = findRefEdges(Index, &V, RefEdges, Visited);
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bool NonRenamableLocal = isNonRenamableLocal(V);
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GlobalValueSummary::GVFlags Flags(V.getLinkage(), NonRenamableLocal,
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/* Live = */ false, V.isDSOLocal());
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// Don't mark variables we won't be able to internalize as read-only.
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GlobalVarSummary::GVarFlags VarFlags(
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!V.hasComdat() && !V.hasAppendingLinkage() && !V.isInterposable() &&
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!V.hasAvailableExternallyLinkage() && !V.hasDLLExportStorageClass());
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auto GVarSummary = llvm::make_unique<GlobalVarSummary>(Flags, VarFlags,
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RefEdges.takeVector());
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if (NonRenamableLocal)
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CantBePromoted.insert(V.getGUID());
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if (HasBlockAddress)
|
|
GVarSummary->setNotEligibleToImport();
|
|
Index.addGlobalValueSummary(V, std::move(GVarSummary));
|
|
}
|
|
|
|
static void
|
|
computeAliasSummary(ModuleSummaryIndex &Index, const GlobalAlias &A,
|
|
DenseSet<GlobalValue::GUID> &CantBePromoted) {
|
|
bool NonRenamableLocal = isNonRenamableLocal(A);
|
|
GlobalValueSummary::GVFlags Flags(A.getLinkage(), NonRenamableLocal,
|
|
/* Live = */ false, A.isDSOLocal());
|
|
auto AS = llvm::make_unique<AliasSummary>(Flags);
|
|
auto *Aliasee = A.getBaseObject();
|
|
auto *AliaseeSummary = Index.getGlobalValueSummary(*Aliasee);
|
|
assert(AliaseeSummary && "Alias expects aliasee summary to be parsed");
|
|
AS->setAliasee(AliaseeSummary);
|
|
if (NonRenamableLocal)
|
|
CantBePromoted.insert(A.getGUID());
|
|
Index.addGlobalValueSummary(A, std::move(AS));
|
|
}
|
|
|
|
// Set LiveRoot flag on entries matching the given value name.
|
|
static void setLiveRoot(ModuleSummaryIndex &Index, StringRef Name) {
|
|
if (ValueInfo VI = Index.getValueInfo(GlobalValue::getGUID(Name)))
|
|
for (auto &Summary : VI.getSummaryList())
|
|
Summary->setLive(true);
|
|
}
|
|
|
|
ModuleSummaryIndex llvm::buildModuleSummaryIndex(
|
|
const Module &M,
|
|
std::function<BlockFrequencyInfo *(const Function &F)> GetBFICallback,
|
|
ProfileSummaryInfo *PSI) {
|
|
assert(PSI);
|
|
bool EnableSplitLTOUnit = false;
|
|
if (auto *MD = mdconst::extract_or_null<ConstantInt>(
|
|
M.getModuleFlag("EnableSplitLTOUnit")))
|
|
EnableSplitLTOUnit = MD->getZExtValue();
|
|
ModuleSummaryIndex Index(/*HaveGVs=*/true, EnableSplitLTOUnit);
|
|
|
|
// Identify the local values in the llvm.used and llvm.compiler.used sets,
|
|
// which should not be exported as they would then require renaming and
|
|
// promotion, but we may have opaque uses e.g. in inline asm. We collect them
|
|
// here because we use this information to mark functions containing inline
|
|
// assembly calls as not importable.
|
|
SmallPtrSet<GlobalValue *, 8> LocalsUsed;
|
|
SmallPtrSet<GlobalValue *, 8> Used;
|
|
// First collect those in the llvm.used set.
|
|
collectUsedGlobalVariables(M, Used, /*CompilerUsed*/ false);
|
|
// Next collect those in the llvm.compiler.used set.
|
|
collectUsedGlobalVariables(M, Used, /*CompilerUsed*/ true);
|
|
DenseSet<GlobalValue::GUID> CantBePromoted;
|
|
for (auto *V : Used) {
|
|
if (V->hasLocalLinkage()) {
|
|
LocalsUsed.insert(V);
|
|
CantBePromoted.insert(V->getGUID());
|
|
}
|
|
}
|
|
|
|
bool HasLocalInlineAsmSymbol = false;
|
|
if (!M.getModuleInlineAsm().empty()) {
|
|
// Collect the local values defined by module level asm, and set up
|
|
// summaries for these symbols so that they can be marked as NoRename,
|
|
// to prevent export of any use of them in regular IR that would require
|
|
// renaming within the module level asm. Note we don't need to create a
|
|
// summary for weak or global defs, as they don't need to be flagged as
|
|
// NoRename, and defs in module level asm can't be imported anyway.
|
|
// Also, any values used but not defined within module level asm should
|
|
// be listed on the llvm.used or llvm.compiler.used global and marked as
|
|
// referenced from there.
|
|
ModuleSymbolTable::CollectAsmSymbols(
|
|
M, [&](StringRef Name, object::BasicSymbolRef::Flags Flags) {
|
|
// Symbols not marked as Weak or Global are local definitions.
|
|
if (Flags & (object::BasicSymbolRef::SF_Weak |
|
|
object::BasicSymbolRef::SF_Global))
|
|
return;
|
|
HasLocalInlineAsmSymbol = true;
|
|
GlobalValue *GV = M.getNamedValue(Name);
|
|
if (!GV)
|
|
return;
|
|
assert(GV->isDeclaration() && "Def in module asm already has definition");
|
|
GlobalValueSummary::GVFlags GVFlags(GlobalValue::InternalLinkage,
|
|
/* NotEligibleToImport = */ true,
|
|
/* Live = */ true,
|
|
/* Local */ GV->isDSOLocal());
|
|
CantBePromoted.insert(GV->getGUID());
|
|
// Create the appropriate summary type.
|
|
if (Function *F = dyn_cast<Function>(GV)) {
|
|
std::unique_ptr<FunctionSummary> Summary =
|
|
llvm::make_unique<FunctionSummary>(
|
|
GVFlags, /*InstCount=*/0,
|
|
FunctionSummary::FFlags{
|
|
F->hasFnAttribute(Attribute::ReadNone),
|
|
F->hasFnAttribute(Attribute::ReadOnly),
|
|
F->hasFnAttribute(Attribute::NoRecurse),
|
|
F->returnDoesNotAlias(),
|
|
/* NoInline = */ false},
|
|
/*EntryCount=*/0, ArrayRef<ValueInfo>{},
|
|
ArrayRef<FunctionSummary::EdgeTy>{},
|
|
ArrayRef<GlobalValue::GUID>{},
|
|
ArrayRef<FunctionSummary::VFuncId>{},
|
|
ArrayRef<FunctionSummary::VFuncId>{},
|
|
ArrayRef<FunctionSummary::ConstVCall>{},
|
|
ArrayRef<FunctionSummary::ConstVCall>{});
|
|
Index.addGlobalValueSummary(*GV, std::move(Summary));
|
|
} else {
|
|
std::unique_ptr<GlobalVarSummary> Summary =
|
|
llvm::make_unique<GlobalVarSummary>(
|
|
GVFlags, GlobalVarSummary::GVarFlags(),
|
|
ArrayRef<ValueInfo>{});
|
|
Index.addGlobalValueSummary(*GV, std::move(Summary));
|
|
}
|
|
});
|
|
}
|
|
|
|
bool IsThinLTO = true;
|
|
if (auto *MD =
|
|
mdconst::extract_or_null<ConstantInt>(M.getModuleFlag("ThinLTO")))
|
|
IsThinLTO = MD->getZExtValue();
|
|
|
|
// Compute summaries for all functions defined in module, and save in the
|
|
// index.
|
|
for (auto &F : M) {
|
|
if (F.isDeclaration())
|
|
continue;
|
|
|
|
DominatorTree DT(const_cast<Function &>(F));
|
|
BlockFrequencyInfo *BFI = nullptr;
|
|
std::unique_ptr<BlockFrequencyInfo> BFIPtr;
|
|
if (GetBFICallback)
|
|
BFI = GetBFICallback(F);
|
|
else if (F.hasProfileData()) {
|
|
LoopInfo LI{DT};
|
|
BranchProbabilityInfo BPI{F, LI};
|
|
BFIPtr = llvm::make_unique<BlockFrequencyInfo>(F, BPI, LI);
|
|
BFI = BFIPtr.get();
|
|
}
|
|
|
|
computeFunctionSummary(Index, M, F, BFI, PSI, DT,
|
|
!LocalsUsed.empty() || HasLocalInlineAsmSymbol,
|
|
CantBePromoted, IsThinLTO);
|
|
}
|
|
|
|
// Compute summaries for all variables defined in module, and save in the
|
|
// index.
|
|
for (const GlobalVariable &G : M.globals()) {
|
|
if (G.isDeclaration())
|
|
continue;
|
|
computeVariableSummary(Index, G, CantBePromoted);
|
|
}
|
|
|
|
// Compute summaries for all aliases defined in module, and save in the
|
|
// index.
|
|
for (const GlobalAlias &A : M.aliases())
|
|
computeAliasSummary(Index, A, CantBePromoted);
|
|
|
|
for (auto *V : LocalsUsed) {
|
|
auto *Summary = Index.getGlobalValueSummary(*V);
|
|
assert(Summary && "Missing summary for global value");
|
|
Summary->setNotEligibleToImport();
|
|
}
|
|
|
|
// The linker doesn't know about these LLVM produced values, so we need
|
|
// to flag them as live in the index to ensure index-based dead value
|
|
// analysis treats them as live roots of the analysis.
|
|
setLiveRoot(Index, "llvm.used");
|
|
setLiveRoot(Index, "llvm.compiler.used");
|
|
setLiveRoot(Index, "llvm.global_ctors");
|
|
setLiveRoot(Index, "llvm.global_dtors");
|
|
setLiveRoot(Index, "llvm.global.annotations");
|
|
|
|
for (auto &GlobalList : Index) {
|
|
// Ignore entries for references that are undefined in the current module.
|
|
if (GlobalList.second.SummaryList.empty())
|
|
continue;
|
|
|
|
assert(GlobalList.second.SummaryList.size() == 1 &&
|
|
"Expected module's index to have one summary per GUID");
|
|
auto &Summary = GlobalList.second.SummaryList[0];
|
|
if (!IsThinLTO) {
|
|
Summary->setNotEligibleToImport();
|
|
continue;
|
|
}
|
|
|
|
bool AllRefsCanBeExternallyReferenced =
|
|
llvm::all_of(Summary->refs(), [&](const ValueInfo &VI) {
|
|
return !CantBePromoted.count(VI.getGUID());
|
|
});
|
|
if (!AllRefsCanBeExternallyReferenced) {
|
|
Summary->setNotEligibleToImport();
|
|
continue;
|
|
}
|
|
|
|
if (auto *FuncSummary = dyn_cast<FunctionSummary>(Summary.get())) {
|
|
bool AllCallsCanBeExternallyReferenced = llvm::all_of(
|
|
FuncSummary->calls(), [&](const FunctionSummary::EdgeTy &Edge) {
|
|
return !CantBePromoted.count(Edge.first.getGUID());
|
|
});
|
|
if (!AllCallsCanBeExternallyReferenced)
|
|
Summary->setNotEligibleToImport();
|
|
}
|
|
}
|
|
|
|
if (!ModuleSummaryDotFile.empty()) {
|
|
std::error_code EC;
|
|
raw_fd_ostream OSDot(ModuleSummaryDotFile, EC, sys::fs::OpenFlags::F_None);
|
|
if (EC)
|
|
report_fatal_error(Twine("Failed to open dot file ") +
|
|
ModuleSummaryDotFile + ": " + EC.message() + "\n");
|
|
Index.exportToDot(OSDot);
|
|
}
|
|
|
|
return Index;
|
|
}
|
|
|
|
AnalysisKey ModuleSummaryIndexAnalysis::Key;
|
|
|
|
ModuleSummaryIndex
|
|
ModuleSummaryIndexAnalysis::run(Module &M, ModuleAnalysisManager &AM) {
|
|
ProfileSummaryInfo &PSI = AM.getResult<ProfileSummaryAnalysis>(M);
|
|
auto &FAM = AM.getResult<FunctionAnalysisManagerModuleProxy>(M).getManager();
|
|
return buildModuleSummaryIndex(
|
|
M,
|
|
[&FAM](const Function &F) {
|
|
return &FAM.getResult<BlockFrequencyAnalysis>(
|
|
*const_cast<Function *>(&F));
|
|
},
|
|
&PSI);
|
|
}
|
|
|
|
char ModuleSummaryIndexWrapperPass::ID = 0;
|
|
|
|
INITIALIZE_PASS_BEGIN(ModuleSummaryIndexWrapperPass, "module-summary-analysis",
|
|
"Module Summary Analysis", false, true)
|
|
INITIALIZE_PASS_DEPENDENCY(BlockFrequencyInfoWrapperPass)
|
|
INITIALIZE_PASS_DEPENDENCY(ProfileSummaryInfoWrapperPass)
|
|
INITIALIZE_PASS_END(ModuleSummaryIndexWrapperPass, "module-summary-analysis",
|
|
"Module Summary Analysis", false, true)
|
|
|
|
ModulePass *llvm::createModuleSummaryIndexWrapperPass() {
|
|
return new ModuleSummaryIndexWrapperPass();
|
|
}
|
|
|
|
ModuleSummaryIndexWrapperPass::ModuleSummaryIndexWrapperPass()
|
|
: ModulePass(ID) {
|
|
initializeModuleSummaryIndexWrapperPassPass(*PassRegistry::getPassRegistry());
|
|
}
|
|
|
|
bool ModuleSummaryIndexWrapperPass::runOnModule(Module &M) {
|
|
auto *PSI = &getAnalysis<ProfileSummaryInfoWrapperPass>().getPSI();
|
|
Index.emplace(buildModuleSummaryIndex(
|
|
M,
|
|
[this](const Function &F) {
|
|
return &(this->getAnalysis<BlockFrequencyInfoWrapperPass>(
|
|
*const_cast<Function *>(&F))
|
|
.getBFI());
|
|
},
|
|
PSI));
|
|
return false;
|
|
}
|
|
|
|
bool ModuleSummaryIndexWrapperPass::doFinalization(Module &M) {
|
|
Index.reset();
|
|
return false;
|
|
}
|
|
|
|
void ModuleSummaryIndexWrapperPass::getAnalysisUsage(AnalysisUsage &AU) const {
|
|
AU.setPreservesAll();
|
|
AU.addRequired<BlockFrequencyInfoWrapperPass>();
|
|
AU.addRequired<ProfileSummaryInfoWrapperPass>();
|
|
}
|