llvm/lib/IR/LLVMContext.cpp
Michael Kruse 42a382c204 Introduce llvm.loop.parallel_accesses and llvm.access.group metadata.
The current llvm.mem.parallel_loop_access metadata has a problem in that
it uses LoopIDs. LoopID unfortunately is not loop identifier. It is
neither unique (there's even a regression test assigning the some LoopID
to multiple loops; can otherwise happen if passes such as LoopVersioning
make copies of entire loops) nor persistent (every time a property is
removed/added from a LoopID's MDNode, it will also receive a new LoopID;
this happens e.g. when calling Loop::setLoopAlreadyUnrolled()).
Since most loop transformation passes change the loop attributes (even
if it just to mark that a loop should not be processed again as
llvm.loop.isvectorized does, for the versioned and unversioned loop),
the parallel access information is lost for any subsequent pass.

This patch unlinks LoopIDs and parallel accesses.
llvm.mem.parallel_loop_access metadata on instruction is replaced by
llvm.access.group metadata. llvm.access.group points to a distinct
MDNode with no operands (avoiding the problem to ever need to add/remove
operands), called "access group". Alternatively, it can point to a list
of access groups. The LoopID then has an attribute
llvm.loop.parallel_accesses with all the access groups that are parallel
(no dependencies carries by this loop).

This intentionally avoid any kind of "ID". Loops that are clones/have
their attributes modifies retain the llvm.loop.parallel_accesses
attribute. Access instructions that a cloned point to the same access
group. It is not necessary for each access to have it's own "ID" MDNode,
but those memory access instructions with the same behavior can be
grouped together.

The behavior of llvm.mem.parallel_loop_access is not changed by this
patch, but should be considered deprecated.

Differential Revision: https://reviews.llvm.org/D52116

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349725 91177308-0d34-0410-b5e6-96231b3b80d8
2018-12-20 04:58:07 +00:00

351 lines
11 KiB
C++

//===-- LLVMContext.cpp - Implement LLVMContext ---------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements LLVMContext, as a wrapper around the opaque
// class LLVMContextImpl.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/LLVMContext.h"
#include "LLVMContextImpl.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/Twine.h"
#include "llvm/IR/DiagnosticInfo.h"
#include "llvm/IR/DiagnosticPrinter.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include <cassert>
#include <cstdlib>
#include <string>
#include <utility>
using namespace llvm;
LLVMContext::LLVMContext() : pImpl(new LLVMContextImpl(*this)) {
// Create the fixed metadata kinds. This is done in the same order as the
// MD_* enum values so that they correspond.
std::pair<unsigned, StringRef> MDKinds[] = {
{MD_dbg, "dbg"},
{MD_tbaa, "tbaa"},
{MD_prof, "prof"},
{MD_fpmath, "fpmath"},
{MD_range, "range"},
{MD_tbaa_struct, "tbaa.struct"},
{MD_invariant_load, "invariant.load"},
{MD_alias_scope, "alias.scope"},
{MD_noalias, "noalias"},
{MD_nontemporal, "nontemporal"},
{MD_mem_parallel_loop_access, "llvm.mem.parallel_loop_access"},
{MD_nonnull, "nonnull"},
{MD_dereferenceable, "dereferenceable"},
{MD_dereferenceable_or_null, "dereferenceable_or_null"},
{MD_make_implicit, "make.implicit"},
{MD_unpredictable, "unpredictable"},
{MD_invariant_group, "invariant.group"},
{MD_align, "align"},
{MD_loop, "llvm.loop"},
{MD_type, "type"},
{MD_section_prefix, "section_prefix"},
{MD_absolute_symbol, "absolute_symbol"},
{MD_associated, "associated"},
{MD_callees, "callees"},
{MD_irr_loop, "irr_loop"},
{MD_access_group, "llvm.access.group"},
};
for (auto &MDKind : MDKinds) {
unsigned ID = getMDKindID(MDKind.second);
assert(ID == MDKind.first && "metadata kind id drifted");
(void)ID;
}
auto *DeoptEntry = pImpl->getOrInsertBundleTag("deopt");
assert(DeoptEntry->second == LLVMContext::OB_deopt &&
"deopt operand bundle id drifted!");
(void)DeoptEntry;
auto *FuncletEntry = pImpl->getOrInsertBundleTag("funclet");
assert(FuncletEntry->second == LLVMContext::OB_funclet &&
"funclet operand bundle id drifted!");
(void)FuncletEntry;
auto *GCTransitionEntry = pImpl->getOrInsertBundleTag("gc-transition");
assert(GCTransitionEntry->second == LLVMContext::OB_gc_transition &&
"gc-transition operand bundle id drifted!");
(void)GCTransitionEntry;
SyncScope::ID SingleThreadSSID =
pImpl->getOrInsertSyncScopeID("singlethread");
assert(SingleThreadSSID == SyncScope::SingleThread &&
"singlethread synchronization scope ID drifted!");
(void)SingleThreadSSID;
SyncScope::ID SystemSSID =
pImpl->getOrInsertSyncScopeID("");
assert(SystemSSID == SyncScope::System &&
"system synchronization scope ID drifted!");
(void)SystemSSID;
}
LLVMContext::~LLVMContext() { delete pImpl; }
void LLVMContext::addModule(Module *M) {
pImpl->OwnedModules.insert(M);
}
void LLVMContext::removeModule(Module *M) {
pImpl->OwnedModules.erase(M);
}
//===----------------------------------------------------------------------===//
// Recoverable Backend Errors
//===----------------------------------------------------------------------===//
void LLVMContext::
setInlineAsmDiagnosticHandler(InlineAsmDiagHandlerTy DiagHandler,
void *DiagContext) {
pImpl->InlineAsmDiagHandler = DiagHandler;
pImpl->InlineAsmDiagContext = DiagContext;
}
/// getInlineAsmDiagnosticHandler - Return the diagnostic handler set by
/// setInlineAsmDiagnosticHandler.
LLVMContext::InlineAsmDiagHandlerTy
LLVMContext::getInlineAsmDiagnosticHandler() const {
return pImpl->InlineAsmDiagHandler;
}
/// getInlineAsmDiagnosticContext - Return the diagnostic context set by
/// setInlineAsmDiagnosticHandler.
void *LLVMContext::getInlineAsmDiagnosticContext() const {
return pImpl->InlineAsmDiagContext;
}
void LLVMContext::setDiagnosticHandlerCallBack(
DiagnosticHandler::DiagnosticHandlerTy DiagnosticHandler,
void *DiagnosticContext, bool RespectFilters) {
pImpl->DiagHandler->DiagHandlerCallback = DiagnosticHandler;
pImpl->DiagHandler->DiagnosticContext = DiagnosticContext;
pImpl->RespectDiagnosticFilters = RespectFilters;
}
void LLVMContext::setDiagnosticHandler(std::unique_ptr<DiagnosticHandler> &&DH,
bool RespectFilters) {
pImpl->DiagHandler = std::move(DH);
pImpl->RespectDiagnosticFilters = RespectFilters;
}
void LLVMContext::setDiagnosticsHotnessRequested(bool Requested) {
pImpl->DiagnosticsHotnessRequested = Requested;
}
bool LLVMContext::getDiagnosticsHotnessRequested() const {
return pImpl->DiagnosticsHotnessRequested;
}
void LLVMContext::setDiagnosticsHotnessThreshold(uint64_t Threshold) {
pImpl->DiagnosticsHotnessThreshold = Threshold;
}
uint64_t LLVMContext::getDiagnosticsHotnessThreshold() const {
return pImpl->DiagnosticsHotnessThreshold;
}
yaml::Output *LLVMContext::getDiagnosticsOutputFile() {
return pImpl->DiagnosticsOutputFile.get();
}
void LLVMContext::setDiagnosticsOutputFile(std::unique_ptr<yaml::Output> F) {
pImpl->DiagnosticsOutputFile = std::move(F);
}
DiagnosticHandler::DiagnosticHandlerTy
LLVMContext::getDiagnosticHandlerCallBack() const {
return pImpl->DiagHandler->DiagHandlerCallback;
}
void *LLVMContext::getDiagnosticContext() const {
return pImpl->DiagHandler->DiagnosticContext;
}
void LLVMContext::setYieldCallback(YieldCallbackTy Callback, void *OpaqueHandle)
{
pImpl->YieldCallback = Callback;
pImpl->YieldOpaqueHandle = OpaqueHandle;
}
void LLVMContext::yield() {
if (pImpl->YieldCallback)
pImpl->YieldCallback(this, pImpl->YieldOpaqueHandle);
}
void LLVMContext::emitError(const Twine &ErrorStr) {
diagnose(DiagnosticInfoInlineAsm(ErrorStr));
}
void LLVMContext::emitError(const Instruction *I, const Twine &ErrorStr) {
assert (I && "Invalid instruction");
diagnose(DiagnosticInfoInlineAsm(*I, ErrorStr));
}
static bool isDiagnosticEnabled(const DiagnosticInfo &DI) {
// Optimization remarks are selective. They need to check whether the regexp
// pattern, passed via one of the -pass-remarks* flags, matches the name of
// the pass that is emitting the diagnostic. If there is no match, ignore the
// diagnostic and return.
//
// Also noisy remarks are only enabled if we have hotness information to sort
// them.
if (auto *Remark = dyn_cast<DiagnosticInfoOptimizationBase>(&DI))
return Remark->isEnabled() &&
(!Remark->isVerbose() || Remark->getHotness());
return true;
}
const char *
LLVMContext::getDiagnosticMessagePrefix(DiagnosticSeverity Severity) {
switch (Severity) {
case DS_Error:
return "error";
case DS_Warning:
return "warning";
case DS_Remark:
return "remark";
case DS_Note:
return "note";
}
llvm_unreachable("Unknown DiagnosticSeverity");
}
void LLVMContext::diagnose(const DiagnosticInfo &DI) {
if (auto *OptDiagBase = dyn_cast<DiagnosticInfoOptimizationBase>(&DI)) {
yaml::Output *Out = getDiagnosticsOutputFile();
if (Out) {
// For remarks the << operator takes a reference to a pointer.
auto *P = const_cast<DiagnosticInfoOptimizationBase *>(OptDiagBase);
*Out << P;
}
}
// If there is a report handler, use it.
if (pImpl->DiagHandler &&
(!pImpl->RespectDiagnosticFilters || isDiagnosticEnabled(DI)) &&
pImpl->DiagHandler->handleDiagnostics(DI))
return;
if (!isDiagnosticEnabled(DI))
return;
// Otherwise, print the message with a prefix based on the severity.
DiagnosticPrinterRawOStream DP(errs());
errs() << getDiagnosticMessagePrefix(DI.getSeverity()) << ": ";
DI.print(DP);
errs() << "\n";
if (DI.getSeverity() == DS_Error)
exit(1);
}
void LLVMContext::emitError(unsigned LocCookie, const Twine &ErrorStr) {
diagnose(DiagnosticInfoInlineAsm(LocCookie, ErrorStr));
}
//===----------------------------------------------------------------------===//
// Metadata Kind Uniquing
//===----------------------------------------------------------------------===//
/// Return a unique non-zero ID for the specified metadata kind.
unsigned LLVMContext::getMDKindID(StringRef Name) const {
// If this is new, assign it its ID.
return pImpl->CustomMDKindNames.insert(
std::make_pair(
Name, pImpl->CustomMDKindNames.size()))
.first->second;
}
/// getHandlerNames - Populate client-supplied smallvector using custom
/// metadata name and ID.
void LLVMContext::getMDKindNames(SmallVectorImpl<StringRef> &Names) const {
Names.resize(pImpl->CustomMDKindNames.size());
for (StringMap<unsigned>::const_iterator I = pImpl->CustomMDKindNames.begin(),
E = pImpl->CustomMDKindNames.end(); I != E; ++I)
Names[I->second] = I->first();
}
void LLVMContext::getOperandBundleTags(SmallVectorImpl<StringRef> &Tags) const {
pImpl->getOperandBundleTags(Tags);
}
uint32_t LLVMContext::getOperandBundleTagID(StringRef Tag) const {
return pImpl->getOperandBundleTagID(Tag);
}
SyncScope::ID LLVMContext::getOrInsertSyncScopeID(StringRef SSN) {
return pImpl->getOrInsertSyncScopeID(SSN);
}
void LLVMContext::getSyncScopeNames(SmallVectorImpl<StringRef> &SSNs) const {
pImpl->getSyncScopeNames(SSNs);
}
void LLVMContext::setGC(const Function &Fn, std::string GCName) {
auto It = pImpl->GCNames.find(&Fn);
if (It == pImpl->GCNames.end()) {
pImpl->GCNames.insert(std::make_pair(&Fn, std::move(GCName)));
return;
}
It->second = std::move(GCName);
}
const std::string &LLVMContext::getGC(const Function &Fn) {
return pImpl->GCNames[&Fn];
}
void LLVMContext::deleteGC(const Function &Fn) {
pImpl->GCNames.erase(&Fn);
}
bool LLVMContext::shouldDiscardValueNames() const {
return pImpl->DiscardValueNames;
}
bool LLVMContext::isODRUniquingDebugTypes() const { return !!pImpl->DITypeMap; }
void LLVMContext::enableDebugTypeODRUniquing() {
if (pImpl->DITypeMap)
return;
pImpl->DITypeMap.emplace();
}
void LLVMContext::disableDebugTypeODRUniquing() { pImpl->DITypeMap.reset(); }
void LLVMContext::setDiscardValueNames(bool Discard) {
pImpl->DiscardValueNames = Discard;
}
OptPassGate &LLVMContext::getOptPassGate() const {
return pImpl->getOptPassGate();
}
void LLVMContext::setOptPassGate(OptPassGate& OPG) {
pImpl->setOptPassGate(OPG);
}
const DiagnosticHandler *LLVMContext::getDiagHandlerPtr() const {
return pImpl->DiagHandler.get();
}
std::unique_ptr<DiagnosticHandler> LLVMContext::getDiagnosticHandler() {
return std::move(pImpl->DiagHandler);
}