llvm/lib/IR/LLVMContext.cpp
Adam Nemet f8cec99b2f [OptRemark,LDist] RFC: Add hotness attribute
Summary:
This is the first set of changes implementing the RFC from
http://thread.gmane.org/gmane.comp.compilers.llvm.devel/98334

This is a cross-sectional patch; rather than implementing the hotness
attribute for all optimization remarks and all passes in a patch set, it
implements it for the 'missed-optimization' remark for Loop
Distribution.  My goal is to shake out the design issues before scaling
it up to other types and passes.

Hotness is computed as an integer as the multiplication of the block
frequency with the function entry count.  It's only printed in opt
currently since clang prints the diagnostic fields directly.  E.g.:

  remark: /tmp/t.c:3:3: loop not distributed: use -Rpass-analysis=loop-distribute for more info (hotness: 300)

A new API added is similar to emitOptimizationRemarkMissed.  The
difference is that it additionally takes a code region that the
diagnostic corresponds to.  From this, hotness is computed using BFI.
The new API is exposed via an analysis pass so that it can be made
dependent on LazyBFI.  (Thanks to Hal for the analysis pass idea.)

This feature can all be enabled by setDiagnosticHotnessRequested in the
LLVM context.  If this is off, LazyBFI is not calculated (D22141) so
there should be no overhead.

A new command-line option is added to turn this on in opt.

My plan is to switch all user of emitOptimizationRemark* to use this
module instead.

Reviewers: hfinkel

Subscribers: rcox2, mzolotukhin, llvm-commits

Differential Revision: http://reviews.llvm.org/D21771

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@275583 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-15 17:23:20 +00:00

354 lines
12 KiB
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//===-- 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 "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/Twine.h"
#include "LLVMContextImpl.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.
// Create the 'dbg' metadata kind.
unsigned DbgID = getMDKindID("dbg");
assert(DbgID == MD_dbg && "dbg kind id drifted"); (void)DbgID;
// Create the 'tbaa' metadata kind.
unsigned TBAAID = getMDKindID("tbaa");
assert(TBAAID == MD_tbaa && "tbaa kind id drifted"); (void)TBAAID;
// Create the 'prof' metadata kind.
unsigned ProfID = getMDKindID("prof");
assert(ProfID == MD_prof && "prof kind id drifted"); (void)ProfID;
// Create the 'fpmath' metadata kind.
unsigned FPAccuracyID = getMDKindID("fpmath");
assert(FPAccuracyID == MD_fpmath && "fpmath kind id drifted");
(void)FPAccuracyID;
// Create the 'range' metadata kind.
unsigned RangeID = getMDKindID("range");
assert(RangeID == MD_range && "range kind id drifted");
(void)RangeID;
// Create the 'tbaa.struct' metadata kind.
unsigned TBAAStructID = getMDKindID("tbaa.struct");
assert(TBAAStructID == MD_tbaa_struct && "tbaa.struct kind id drifted");
(void)TBAAStructID;
// Create the 'invariant.load' metadata kind.
unsigned InvariantLdId = getMDKindID("invariant.load");
assert(InvariantLdId == MD_invariant_load && "invariant.load kind id drifted");
(void)InvariantLdId;
// Create the 'alias.scope' metadata kind.
unsigned AliasScopeID = getMDKindID("alias.scope");
assert(AliasScopeID == MD_alias_scope && "alias.scope kind id drifted");
(void)AliasScopeID;
// Create the 'noalias' metadata kind.
unsigned NoAliasID = getMDKindID("noalias");
assert(NoAliasID == MD_noalias && "noalias kind id drifted");
(void)NoAliasID;
// Create the 'nontemporal' metadata kind.
unsigned NonTemporalID = getMDKindID("nontemporal");
assert(NonTemporalID == MD_nontemporal && "nontemporal kind id drifted");
(void)NonTemporalID;
// Create the 'llvm.mem.parallel_loop_access' metadata kind.
unsigned MemParallelLoopAccessID = getMDKindID("llvm.mem.parallel_loop_access");
assert(MemParallelLoopAccessID == MD_mem_parallel_loop_access &&
"mem_parallel_loop_access kind id drifted");
(void)MemParallelLoopAccessID;
// Create the 'nonnull' metadata kind.
unsigned NonNullID = getMDKindID("nonnull");
assert(NonNullID == MD_nonnull && "nonnull kind id drifted");
(void)NonNullID;
// Create the 'dereferenceable' metadata kind.
unsigned DereferenceableID = getMDKindID("dereferenceable");
assert(DereferenceableID == MD_dereferenceable &&
"dereferenceable kind id drifted");
(void)DereferenceableID;
// Create the 'dereferenceable_or_null' metadata kind.
unsigned DereferenceableOrNullID = getMDKindID("dereferenceable_or_null");
assert(DereferenceableOrNullID == MD_dereferenceable_or_null &&
"dereferenceable_or_null kind id drifted");
(void)DereferenceableOrNullID;
// Create the 'make.implicit' metadata kind.
unsigned MakeImplicitID = getMDKindID("make.implicit");
assert(MakeImplicitID == MD_make_implicit &&
"make.implicit kind id drifted");
(void)MakeImplicitID;
// Create the 'unpredictable' metadata kind.
unsigned UnpredictableID = getMDKindID("unpredictable");
assert(UnpredictableID == MD_unpredictable &&
"unpredictable kind id drifted");
(void)UnpredictableID;
// Create the 'invariant.group' metadata kind.
unsigned InvariantGroupId = getMDKindID("invariant.group");
assert(InvariantGroupId == MD_invariant_group &&
"invariant.group kind id drifted");
(void)InvariantGroupId;
// Create the 'align' metadata kind.
unsigned AlignID = getMDKindID("align");
assert(AlignID == MD_align && "align kind id drifted");
(void)AlignID;
// Create the 'llvm.loop' metadata kind.
unsigned LoopID = getMDKindID("llvm.loop");
assert(LoopID == MD_loop && "llvm.loop kind id drifted");
(void)LoopID;
unsigned TypeID = getMDKindID("type");
assert(TypeID == MD_type && "type kind id drifted");
(void)TypeID;
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;
}
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::setDiagnosticHandler(DiagnosticHandlerTy DiagnosticHandler,
void *DiagnosticContext,
bool RespectFilters) {
pImpl->DiagnosticHandler = DiagnosticHandler;
pImpl->DiagnosticContext = DiagnosticContext;
pImpl->RespectDiagnosticFilters = RespectFilters;
}
void LLVMContext::setDiagnosticHotnessRequested(bool Requested) {
pImpl->DiagnosticHotnessRequested = Requested;
}
bool LLVMContext::getDiagnosticHotnessRequested() const {
return pImpl->DiagnosticHotnessRequested;
}
LLVMContext::DiagnosticHandlerTy LLVMContext::getDiagnosticHandler() const {
return pImpl->DiagnosticHandler;
}
void *LLVMContext::getDiagnosticContext() const {
return pImpl->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.
if (auto *Remark = dyn_cast<DiagnosticInfoOptimizationBase>(&DI))
return Remark->isEnabled();
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 there is a report handler, use it.
if (pImpl->DiagnosticHandler) {
if (!pImpl->RespectDiagnosticFilters || isDiagnosticEnabled(DI))
pImpl->DiagnosticHandler(DI, pImpl->DiagnosticContext);
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);
}
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;
}
OptBisect &LLVMContext::getOptBisect() {
return pImpl->getOptBisect();
}