namespace {
namespace stats {
STATISTIC(EmittedFragments, "Number of emitted assembler fragments - total");
-STATISTIC(EmittedInstFragments,
- "Number of emitted assembler fragments - instruction");
+STATISTIC(EmittedRelaxableFragments,
+ "Number of emitted assembler fragments - relaxable");
STATISTIC(EmittedDataFragments,
"Number of emitted assembler fragments - data");
+STATISTIC(EmittedCompactEncodedInstFragments,
+ "Number of emitted assembler fragments - compact encoded inst");
STATISTIC(EmittedAlignFragments,
"Number of emitted assembler fragments - align");
STATISTIC(EmittedFillFragments,
return F->getLayoutOrder() <= LastValid->getLayoutOrder();
}
-void MCAsmLayout::invalidateFragmentsAfter(MCFragment *F) {
+void MCAsmLayout::invalidateFragmentsFrom(MCFragment *F) {
// If this fragment wasn't already valid, we don't need to do anything.
if (!isFragmentValid(F))
return;
- // Otherwise, reset the last valid fragment to this fragment.
+ // Otherwise, reset the last valid fragment to the previous fragment
+ // (if this is the first fragment, it will be NULL).
const MCSectionData &SD = *F->getParent();
- LastValidFragment[&SD] = F;
+ LastValidFragment[&SD] = F->getPrevNode();
}
void MCAsmLayout::ensureValid(const MCFragment *F) const {
uint64_t MCAsmLayout::computeBundlePadding(const MCFragment *F,
uint64_t FOffset, uint64_t FSize) {
uint64_t BundleSize = Assembler.getBundleAlignSize();
- assert(BundleSize > 0 &&
+ assert(BundleSize > 0 &&
"computeBundlePadding should only be called if bundling is enabled");
uint64_t BundleMask = BundleSize - 1;
uint64_t OffsetInBundle = FOffset & BundleMask;
+ uint64_t EndOfFragment = OffsetInBundle + FSize;
- // If the fragment would cross a bundle boundary, add enough padding until
- // the end of the current bundle.
- if (OffsetInBundle + FSize > BundleSize)
+ // There are two kinds of bundling restrictions:
+ //
+ // 1) For alignToBundleEnd(), add padding to ensure that the fragment will
+ // *end* on a bundle boundary.
+ // 2) Otherwise, check if the fragment would cross a bundle boundary. If it
+ // would, add padding until the end of the bundle so that the fragment
+ // will start in a new one.
+ if (F->alignToBundleEnd()) {
+ // Three possibilities here:
+ //
+ // A) The fragment just happens to end at a bundle boundary, so we're good.
+ // B) The fragment ends before the current bundle boundary: pad it just
+ // enough to reach the boundary.
+ // C) The fragment ends after the current bundle boundary: pad it until it
+ // reaches the end of the next bundle boundary.
+ //
+ // Note: this code could be made shorter with some modulo trickery, but it's
+ // intentionally kept in its more explicit form for simplicity.
+ if (EndOfFragment == BundleSize)
+ return 0;
+ else if (EndOfFragment < BundleSize)
+ return BundleSize - EndOfFragment;
+ else { // EndOfFragment > BundleSize
+ return 2 * BundleSize - EndOfFragment;
+ }
+ } else if (EndOfFragment > BundleSize)
return BundleSize - OffsetInBundle;
else
return 0;
/* *** */
+MCEncodedFragmentWithFixups::~MCEncodedFragmentWithFixups() {
+}
+
+/* *** */
+
MCSectionData::MCSectionData() : Section(0) {}
MCSectionData::MCSectionData(const MCSection &_Section, MCAssembler *A)
: Section(&_Section),
Ordinal(~UINT32_C(0)),
Alignment(1),
- BundleLocked(false), BundleGroupBeforeFirstInst(false),
+ BundleLockState(NotBundleLocked), BundleGroupBeforeFirstInst(false),
HasInstructions(false)
{
if (A)
A->getSectionList().push_back(this);
}
+MCSectionData::iterator
+MCSectionData::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 *)0));
+ 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;
+ 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;
+}
+
/* *** */
MCSymbolData::MCSymbolData() : Symbol(0) {}
raw_ostream &OS_)
: Context(Context_), Backend(Backend_), Emitter(Emitter_), Writer(Writer_),
OS(OS_), BundleAlignSize(0), RelaxAll(false), NoExecStack(false),
- SubsectionsViaSymbols(false) {
+ SubsectionsViaSymbols(false), ELFHeaderEFlags(0) {
}
MCAssembler::~MCAssembler() {
RelaxAll = false;
NoExecStack = false;
SubsectionsViaSymbols = false;
+ ELFHeaderEFlags = 0;
// reset objects owned by us
getBackend().reset();
const MCFragment &F) const {
switch (F.getKind()) {
case MCFragment::FT_Data:
- return cast<MCDataFragment>(F).getContents().size();
+ case MCFragment::FT_Relaxable:
+ case MCFragment::FT_CompactEncodedInst:
+ return cast<MCEncodedFragment>(F).getContents().size();
case MCFragment::FT_Fill:
return cast<MCFillFragment>(F).getSize();
- case MCFragment::FT_Inst:
- return cast<MCInstFragment>(F).getInstSize();
case MCFragment::FT_LEB:
return cast<MCLEBFragment>(F).getContents().size();
}
case MCFragment::FT_Org: {
- MCOrgFragment &OF = cast<MCOrgFragment>(F);
+ const MCOrgFragment &OF = cast<MCOrgFragment>(F);
int64_t TargetLocation;
if (!OF.getOffset().EvaluateAsAbsolute(TargetLocation, Layout))
report_fatal_error("expected assembly-time absolute expression");
//
//
// BundlePadding
- // |||
+ // |||
// -------------------------------------
// Prev |##########| F |
// -------------------------------------
/// \brief Write the contents of a fragment to the given object writer. Expects
/// a MCEncodedFragment.
static void writeFragmentContents(const MCFragment &F, MCObjectWriter *OW) {
- MCEncodedFragment &EF = cast<MCEncodedFragment>(F);
+ const MCEncodedFragment &EF = cast<MCEncodedFragment>(F);
OW->WriteBytes(EF.getContents());
}
const MCFragment &F) {
MCObjectWriter *OW = &Asm.getWriter();
+ // FIXME: Embed in fragments instead?
+ uint64_t FragmentSize = Asm.computeFragmentSize(Layout, F);
+
// Should NOP padding be written out before this fragment?
unsigned BundlePadding = F.getBundlePadding();
if (BundlePadding > 0) {
assert(F.hasInstructions() &&
"Writing bundle padding for a fragment without instructions");
+ unsigned TotalLength = BundlePadding + static_cast<unsigned>(FragmentSize);
+ if (F.alignToBundleEnd() && TotalLength > Asm.getBundleAlignSize()) {
+ // If the padding itself crosses a bundle boundary, it must be emitted
+ // in 2 pieces, since even nop instructions must not cross boundaries.
+ // v--------------v <- BundleAlignSize
+ // v---------v <- BundlePadding
+ // ----------------------------
+ // | Prev |####|####| F |
+ // ----------------------------
+ // ^-------------------^ <- TotalLength
+ unsigned DistanceToBoundary = TotalLength - Asm.getBundleAlignSize();
+ if (!Asm.getBackend().writeNopData(DistanceToBoundary, OW))
+ report_fatal_error("unable to write NOP sequence of " +
+ Twine(DistanceToBoundary) + " bytes");
+ BundlePadding -= DistanceToBoundary;
+ }
if (!Asm.getBackend().writeNopData(BundlePadding, OW))
report_fatal_error("unable to write NOP sequence of " +
Twine(BundlePadding) + " bytes");
++stats::EmittedFragments;
- // FIXME: Embed in fragments instead?
- uint64_t FragmentSize = Asm.computeFragmentSize(Layout, F);
switch (F.getKind()) {
case MCFragment::FT_Align: {
++stats::EmittedAlignFragments;
- MCAlignFragment &AF = cast<MCAlignFragment>(F);
+ const MCAlignFragment &AF = cast<MCAlignFragment>(F);
uint64_t Count = FragmentSize / AF.getValueSize();
assert(AF.getValueSize() && "Invalid virtual align in concrete fragment!");
writeFragmentContents(F, OW);
break;
- case MCFragment::FT_Inst:
- ++stats::EmittedInstFragments;
+ case MCFragment::FT_Relaxable:
+ ++stats::EmittedRelaxableFragments;
+ writeFragmentContents(F, OW);
+ break;
+
+ case MCFragment::FT_CompactEncodedInst:
+ ++stats::EmittedCompactEncodedInstFragments;
writeFragmentContents(F, OW);
break;
case MCFragment::FT_Fill: {
++stats::EmittedFillFragments;
- MCFillFragment &FF = cast<MCFillFragment>(F);
+ const MCFillFragment &FF = cast<MCFillFragment>(F);
assert(FF.getValueSize() && "Invalid virtual align in concrete fragment!");
}
case MCFragment::FT_LEB: {
- MCLEBFragment &LF = cast<MCLEBFragment>(F);
+ const MCLEBFragment &LF = cast<MCLEBFragment>(F);
OW->WriteBytes(LF.getContents().str());
break;
}
case MCFragment::FT_Org: {
++stats::EmittedOrgFragments;
- MCOrgFragment &OF = cast<MCOrgFragment>(F);
+ const MCOrgFragment &OF = cast<MCOrgFragment>(F);
for (uint64_t i = 0, e = FragmentSize; i != e; ++i)
OW->Write8(uint8_t(OF.getValue()));
// Check that we aren't trying to write a non-zero contents (or fixups)
// into a virtual section. This is to support clients which use standard
// directives to fill the contents of virtual sections.
- MCDataFragment &DF = cast<MCDataFragment>(*it);
+ const MCDataFragment &DF = cast<MCDataFragment>(*it);
assert(DF.fixup_begin() == DF.fixup_end() &&
"Cannot have fixups in virtual section!");
for (unsigned i = 0, e = DF.getContents().size(); i != e; ++i)
case MCFragment::FT_Align:
// Check that we aren't trying to write a non-zero value into a virtual
// section.
- assert((!cast<MCAlignFragment>(it)->getValueSize() ||
- !cast<MCAlignFragment>(it)->getValue()) &&
+ assert((cast<MCAlignFragment>(it)->getValueSize() == 0 ||
+ cast<MCAlignFragment>(it)->getValue() == 0) &&
"Invalid align in virtual section!");
break;
case MCFragment::FT_Fill:
- assert(!cast<MCFillFragment>(it)->getValueSize() &&
+ assert((cast<MCFillFragment>(it)->getValueSize() == 0 ||
+ cast<MCFillFragment>(it)->getValue() == 0) &&
"Invalid fill in virtual section!");
break;
}
for (MCAssembler::iterator it = begin(), ie = end(); it != ie; ++it) {
for (MCSectionData::iterator it2 = it->begin(),
ie2 = it->end(); it2 != ie2; ++it2) {
- MCEncodedFragment *F = dyn_cast<MCEncodedFragment>(it2);
+ MCEncodedFragmentWithFixups *F =
+ dyn_cast<MCEncodedFragmentWithFixups>(it2);
if (F) {
- for (MCEncodedFragment::fixup_iterator it3 = F->fixup_begin(),
+ for (MCEncodedFragmentWithFixups::fixup_iterator it3 = F->fixup_begin(),
ie3 = F->fixup_end(); it3 != ie3; ++it3) {
MCFixup &Fixup = *it3;
uint64_t FixedValue = handleFixup(Layout, *F, Fixup);
}
bool MCAssembler::fixupNeedsRelaxation(const MCFixup &Fixup,
- const MCInstFragment *DF,
+ const MCRelaxableFragment *DF,
const MCAsmLayout &Layout) const {
// If we cannot resolve the fixup value, it requires relaxation.
MCValue Target;
return getBackend().fixupNeedsRelaxation(Fixup, Value, DF, Layout);
}
-bool MCAssembler::fragmentNeedsRelaxation(const MCInstFragment *IF,
+bool MCAssembler::fragmentNeedsRelaxation(const MCRelaxableFragment *F,
const MCAsmLayout &Layout) const {
// If this inst doesn't ever need relaxation, ignore it. This occurs when we
// are intentionally pushing out inst fragments, or because we relaxed a
// previous instruction to one that doesn't need relaxation.
- if (!getBackend().mayNeedRelaxation(IF->getInst()))
+ if (!getBackend().mayNeedRelaxation(F->getInst()))
return false;
- for (MCInstFragment::const_fixup_iterator it = IF->fixup_begin(),
- ie = IF->fixup_end(); it != ie; ++it)
- if (fixupNeedsRelaxation(*it, IF, Layout))
+ for (MCRelaxableFragment::const_fixup_iterator it = F->fixup_begin(),
+ ie = F->fixup_end(); it != ie; ++it)
+ if (fixupNeedsRelaxation(*it, F, Layout))
return true;
return false;
}
bool MCAssembler::relaxInstruction(MCAsmLayout &Layout,
- MCInstFragment &IF) {
- if (!fragmentNeedsRelaxation(&IF, Layout))
+ MCRelaxableFragment &F) {
+ if (!fragmentNeedsRelaxation(&F, Layout))
return false;
++stats::RelaxedInstructions;
// Relax the fragment.
MCInst Relaxed;
- getBackend().relaxInstruction(IF.getInst(), Relaxed);
+ getBackend().relaxInstruction(F.getInst(), Relaxed);
// Encode the new instruction.
//
getEmitter().EncodeInstruction(Relaxed, VecOS, Fixups);
VecOS.flush();
- // Update the instruction fragment.
- IF.setInst(Relaxed);
- IF.getContents() = Code;
- IF.getFixups() = Fixups;
+ // Update the fragment.
+ F.setInst(Relaxed);
+ F.getContents() = Code;
+ F.getFixups() = Fixups;
return true;
}
bool MCAssembler::relaxDwarfLineAddr(MCAsmLayout &Layout,
MCDwarfLineAddrFragment &DF) {
+ MCContext &Context = Layout.getAssembler().getContext();
int64_t AddrDelta = 0;
uint64_t OldSize = DF.getContents().size();
bool IsAbs = DF.getAddrDelta().EvaluateAsAbsolute(AddrDelta, Layout);
SmallString<8> &Data = DF.getContents();
Data.clear();
raw_svector_ostream OSE(Data);
- MCDwarfLineAddr::Encode(LineDelta, AddrDelta, OSE);
+ MCDwarfLineAddr::Encode(Context, LineDelta, AddrDelta, OSE);
OSE.flush();
return OldSize != Data.size();
}
bool MCAssembler::relaxDwarfCallFrameFragment(MCAsmLayout &Layout,
MCDwarfCallFrameFragment &DF) {
+ MCContext &Context = Layout.getAssembler().getContext();
int64_t AddrDelta = 0;
uint64_t OldSize = DF.getContents().size();
bool IsAbs = DF.getAddrDelta().EvaluateAsAbsolute(AddrDelta, Layout);
SmallString<8> &Data = DF.getContents();
Data.clear();
raw_svector_ostream OSE(Data);
- MCDwarfFrameEmitter::EncodeAdvanceLoc(AddrDelta, OSE);
+ MCDwarfFrameEmitter::EncodeAdvanceLoc(Context, AddrDelta, OSE);
OSE.flush();
return OldSize != Data.size();
}
switch(I->getKind()) {
default:
break;
- case MCFragment::FT_Inst:
+ case MCFragment::FT_Relaxable:
assert(!getRelaxAll() &&
- "Did not expect a MCInstFragment in RelaxAll mode");
- RelaxedFrag = relaxInstruction(Layout, *cast<MCInstFragment>(I));
+ "Did not expect a MCRelaxableFragment in RelaxAll mode");
+ RelaxedFrag = relaxInstruction(Layout, *cast<MCRelaxableFragment>(I));
break;
case MCFragment::FT_Dwarf:
RelaxedFrag = relaxDwarfLineAddr(Layout,
FirstRelaxedFragment = I;
}
if (FirstRelaxedFragment) {
- Layout.invalidateFragmentsAfter(FirstRelaxedFragment);
+ Layout.invalidateFragmentsFrom(FirstRelaxedFragment);
return true;
}
return false;
switch (getKind()) {
case MCFragment::FT_Align: OS << "MCAlignFragment"; break;
case MCFragment::FT_Data: OS << "MCDataFragment"; break;
+ case MCFragment::FT_CompactEncodedInst:
+ OS << "MCCompactEncodedInstFragment"; break;
case MCFragment::FT_Fill: OS << "MCFillFragment"; break;
- case MCFragment::FT_Inst: OS << "MCInstFragment"; break;
+ case MCFragment::FT_Relaxable: OS << "MCRelaxableFragment"; break;
case MCFragment::FT_Org: OS << "MCOrgFragment"; break;
case MCFragment::FT_Dwarf: OS << "MCDwarfFragment"; break;
case MCFragment::FT_DwarfFrame: OS << "MCDwarfCallFrameFragment"; break;
OS << "<MCFragment " << (void*) this << " LayoutOrder:" << LayoutOrder
<< " Offset:" << Offset
<< " HasInstructions:" << hasInstructions()
- << " BundlePadding:" << getBundlePadding() << ">";
+ << " BundlePadding:" << static_cast<unsigned>(getBundlePadding()) << ">";
switch (getKind()) {
case MCFragment::FT_Align: {
}
break;
}
+ case MCFragment::FT_CompactEncodedInst: {
+ const MCCompactEncodedInstFragment *CEIF =
+ cast<MCCompactEncodedInstFragment>(this);
+ OS << "\n ";
+ OS << " Contents:[";
+ const SmallVectorImpl<char> &Contents = CEIF->getContents();
+ for (unsigned i = 0, e = Contents.size(); i != e; ++i) {
+ if (i) OS << ",";
+ OS << hexdigit((Contents[i] >> 4) & 0xF) << hexdigit(Contents[i] & 0xF);
+ }
+ OS << "] (" << Contents.size() << " bytes)";
+ break;
+ }
case MCFragment::FT_Fill: {
const MCFillFragment *FF = cast<MCFillFragment>(this);
OS << " Value:" << FF->getValue() << " ValueSize:" << FF->getValueSize()
<< " Size:" << FF->getSize();
break;
}
- case MCFragment::FT_Inst: {
- const MCInstFragment *IF = cast<MCInstFragment>(this);
+ case MCFragment::FT_Relaxable: {
+ const MCRelaxableFragment *F = cast<MCRelaxableFragment>(this);
OS << "\n ";
OS << " Inst:";
- IF->getInst().dump_pretty(OS);
+ F->getInst().dump_pretty(OS);
break;
}
case MCFragment::FT_Org: {
// anchors for MC*Fragment vtables
void MCEncodedFragment::anchor() { }
+void MCEncodedFragmentWithFixups::anchor() { }
void MCDataFragment::anchor() { }
-void MCInstFragment::anchor() { }
+void MCCompactEncodedInstFragment::anchor() { }
+void MCRelaxableFragment::anchor() { }
void MCAlignFragment::anchor() { }
void MCFillFragment::anchor() { }
void MCOrgFragment::anchor() { }
projects / oota-llvm.git / blobdiff