llvm/lib/IR/ModuleSummaryIndex.cpp
Mehdi Amini 7fe28f81db ThinLTO: handles modules with empty summaries
We need to add an entry in the combined-index for modules that have
a hash but otherwise empty summary, this is needed so that we can
get the hash for the module.

Also, if no entry is present in the combined index for a module, we
need to skip it when trying to compute a cache entry.

Differential Revision: https://reviews.llvm.org/D25300

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@283654 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-08 04:44:18 +00:00

107 lines
4.0 KiB
C++

//===-- ModuleSummaryIndex.cpp - Module Summary Index ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the module index and summary classes for the
// IR library.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/ModuleSummaryIndex.h"
#include "llvm/ADT/StringMap.h"
using namespace llvm;
// Create the combined module index/summary from multiple
// per-module instances.
void ModuleSummaryIndex::mergeFrom(std::unique_ptr<ModuleSummaryIndex> Other,
uint64_t NextModuleId) {
if (Other->modulePaths().empty())
return;
assert(Other->modulePaths().size() == 1 &&
"Can only merge from an single-module index at that time");
StringRef OtherModPath = Other->modulePaths().begin()->first();
StringRef ModPath = addModulePath(OtherModPath, NextModuleId,
Other->getModuleHash(OtherModPath))
->first();
for (auto &OtherGlobalValSummaryLists : *Other) {
GlobalValue::GUID ValueGUID = OtherGlobalValSummaryLists.first;
GlobalValueSummaryList &List = OtherGlobalValSummaryLists.second;
// Assert that the value summary list only has one entry, since we shouldn't
// have duplicate names within a single per-module index.
assert(List.size() == 1);
std::unique_ptr<GlobalValueSummary> Summary = std::move(List.front());
// Note the module path string ref was copied above and is still owned by
// the original per-module index. Reset it to the new module path
// string reference owned by the combined index.
Summary->setModulePath(ModPath);
// Add new value summary to existing list. There may be duplicates when
// combining GlobalValueMap entries, due to COMDAT values. Any local
// values were given unique global IDs.
addGlobalValueSummary(ValueGUID, std::move(Summary));
}
}
void ModuleSummaryIndex::removeEmptySummaryEntries() {
for (auto MI = begin(), MIE = end(); MI != MIE;) {
// Only expect this to be called on a per-module index, which has a single
// entry per value entry list.
assert(MI->second.size() == 1);
if (!MI->second[0])
MI = GlobalValueMap.erase(MI);
else
++MI;
}
}
// Collect for the given module the list of function it defines
// (GUID -> Summary).
void ModuleSummaryIndex::collectDefinedFunctionsForModule(
StringRef ModulePath, GVSummaryMapTy &GVSummaryMap) const {
for (auto &GlobalList : *this) {
auto GUID = GlobalList.first;
for (auto &GlobSummary : GlobalList.second) {
auto *Summary = dyn_cast_or_null<FunctionSummary>(GlobSummary.get());
if (!Summary)
// Ignore global variable, focus on functions
continue;
// Ignore summaries from other modules.
if (Summary->modulePath() != ModulePath)
continue;
GVSummaryMap[GUID] = Summary;
}
}
}
// Collect for each module the list of function it defines (GUID -> Summary).
void ModuleSummaryIndex::collectDefinedGVSummariesPerModule(
StringMap<GVSummaryMapTy> &ModuleToDefinedGVSummaries) const {
for (auto &GlobalList : *this) {
auto GUID = GlobalList.first;
for (auto &Summary : GlobalList.second) {
ModuleToDefinedGVSummaries[Summary->modulePath()][GUID] = Summary.get();
}
}
}
GlobalValueSummary *
ModuleSummaryIndex::getGlobalValueSummary(uint64_t ValueGUID,
bool PerModuleIndex) const {
auto SummaryList = findGlobalValueSummaryList(ValueGUID);
assert(SummaryList != end() && "GlobalValue not found in index");
assert((!PerModuleIndex || SummaryList->second.size() == 1) &&
"Expected a single entry per global value in per-module index");
auto &Summary = SummaryList->second[0];
return Summary.get();
}