llvm/lib/IR/LLVMContext.cpp
Shuxin Yang 985dac6579 Memory Dependence Analysis (not mem-dep test) take advantage of "invariant.load" metadata.
The "invariant.load" metadata indicates the memory unit being accessed is immutable.
A load annotated with this metadata can be moved across any store.

As I am not sure if it is legal to move such loads across barrier/fence, this
change dose not allow such transformation.

rdar://11311484

Thank Arnold for code review.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176562 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-06 17:48:48 +00:00

169 lines
5.6 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/IR/Constants.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Metadata.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/SourceMgr.h"
#include <cctype>
using namespace llvm;
static ManagedStatic<LLVMContext> GlobalContext;
LLVMContext& llvm::getGlobalContext() {
return *GlobalContext;
}
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;
}
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::emitError(const Twine &ErrorStr) {
emitError(0U, ErrorStr);
}
void LLVMContext::emitError(const Instruction *I, const Twine &ErrorStr) {
unsigned LocCookie = 0;
if (const MDNode *SrcLoc = I->getMetadata("srcloc")) {
if (SrcLoc->getNumOperands() != 0)
if (const ConstantInt *CI = dyn_cast<ConstantInt>(SrcLoc->getOperand(0)))
LocCookie = CI->getZExtValue();
}
return emitError(LocCookie, ErrorStr);
}
void LLVMContext::emitError(unsigned LocCookie, const Twine &ErrorStr) {
// If there is no error handler installed, just print the error and exit.
if (pImpl->InlineAsmDiagHandler == 0) {
errs() << "error: " << ErrorStr << "\n";
exit(1);
}
// If we do have an error handler, we can report the error and keep going.
SMDiagnostic Diag("", SourceMgr::DK_Error, ErrorStr.str());
pImpl->InlineAsmDiagHandler(Diag, pImpl->InlineAsmDiagContext, LocCookie);
}
//===----------------------------------------------------------------------===//
// Metadata Kind Uniquing
//===----------------------------------------------------------------------===//
#ifndef NDEBUG
/// isValidName - Return true if Name is a valid custom metadata handler name.
static bool isValidName(StringRef MDName) {
if (MDName.empty())
return false;
if (!std::isalpha(static_cast<unsigned char>(MDName[0])))
return false;
for (StringRef::iterator I = MDName.begin() + 1, E = MDName.end(); I != E;
++I) {
if (!std::isalnum(static_cast<unsigned char>(*I)) && *I != '_' &&
*I != '-' && *I != '.')
return false;
}
return true;
}
#endif
/// getMDKindID - Return a unique non-zero ID for the specified metadata kind.
unsigned LLVMContext::getMDKindID(StringRef Name) const {
assert(isValidName(Name) && "Invalid MDNode name");
// If this is new, assign it its ID.
return
pImpl->CustomMDKindNames.GetOrCreateValue(
Name, pImpl->CustomMDKindNames.size()).second;
}
/// getHandlerNames - Populate client supplied smallvector using custome
/// 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();
}