llvm-project/llvm/lib/MC/MCSection.cpp

102 lines
3.0 KiB
C++

//===- lib/MC/MCSection.cpp - Machine Code Section Representation ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/MC/MCSection.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCFragment.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <utility>
using namespace llvm;
MCSection::MCSection(SectionVariant V, SectionKind K, MCSymbol *Begin)
: Begin(Begin), BundleGroupBeforeFirstInst(false), HasInstructions(false),
IsRegistered(false), DummyFragment(this), Variant(V), Kind(K) {}
MCSymbol *MCSection::getEndSymbol(MCContext &Ctx) {
if (!End)
End = Ctx.createTempSymbol("sec_end", true);
return End;
}
bool MCSection::hasEnded() const { return End && End->isInSection(); }
MCSection::~MCSection() = default;
void MCSection::setBundleLockState(BundleLockStateType NewState) {
if (NewState == NotBundleLocked) {
if (BundleLockNestingDepth == 0) {
report_fatal_error("Mismatched bundle_lock/unlock directives");
}
if (--BundleLockNestingDepth == 0) {
BundleLockState = NotBundleLocked;
}
return;
}
// If any of the directives is an align_to_end directive, the whole nested
// group is align_to_end. So don't downgrade from align_to_end to just locked.
if (BundleLockState != BundleLockedAlignToEnd) {
BundleLockState = NewState;
}
++BundleLockNestingDepth;
}
MCSection::iterator
MCSection::getSubsectionInsertionPoint(unsigned Subsection) {
if (Subsection == 0 && SubsectionFragmentMap.empty())
return end();
SmallVectorImpl<std::pair<unsigned, MCFragment *>>::iterator MI =
std::lower_bound(SubsectionFragmentMap.begin(),
SubsectionFragmentMap.end(),
std::make_pair(Subsection, (MCFragment *)nullptr));
bool ExactMatch = false;
if (MI != SubsectionFragmentMap.end()) {
ExactMatch = MI->first == Subsection;
if (ExactMatch)
++MI;
}
iterator IP;
if (MI == SubsectionFragmentMap.end())
IP = end();
else
IP = MI->second->getIterator();
if (!ExactMatch && Subsection != 0) {
// The GNU as documentation claims that subsections have an alignment of 4,
// although this appears not to be the case.
MCFragment *F = new MCDataFragment();
SubsectionFragmentMap.insert(MI, std::make_pair(Subsection, F));
getFragmentList().insert(IP, F);
F->setParent(this);
}
return IP;
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
LLVM_DUMP_METHOD void MCSection::dump() {
raw_ostream &OS = errs();
OS << "<MCSection";
OS << " Fragments:[\n ";
for (auto it = begin(), ie = end(); it != ie; ++it) {
if (it != begin())
OS << ",\n ";
it->dump();
}
OS << "]>";
}
#endif