Commit 58b10df5 authored by David Blaikie's avatar David Blaikie
Browse files

DebugInfo: Move SectionLabel tracking into CU's addRange 

This makes the SectionLabel handling more resilient - specifically for
future PROPELLER work which will have more CU ranges (rather than just
one per function).

Ultimately it might be nice to make this more general/resilient to
arbitrary labels (rather than relying on the labels being created for CU
ranges & then being reused by ranges, loclists, and possibly other
addresses). It's possible that other (non-rnglist/loclist) uses of
addresses will need the addresses to be in SectionLabels earlier (eg:
move the CU.addRange to be done on function begin, rather than function
end, so during function emission they are already populated for other
use).
parent 46ed9331

llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp

+2 −0
Original line number Diff line number Diff line
@@ -328,6 +328,8 @@ DIE *DwarfCompileUnit::getOrCreateCommonBlock( 
}



void DwarfCompileUnit::addRange(RangeSpan Range) {

  DD->insertSectionLabel(Range.Begin);



  bool SameAsPrevCU = this == DD->getPrevCU();

  DD->setPrevCU(this);

  // If we have no current ranges just add the range and return, otherwise,

llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp

+6 −5
Original line number Diff line number Diff line
@@ -1833,9 +1833,6 @@ void DwarfDebug::beginFunctionImpl(const MachineFunction *MF) { 
  if (SP->getUnit()->getEmissionKind() == DICompileUnit::NoDebug)

    return;



  SectionLabels.insert(std::make_pair(&Asm->getFunctionBegin()->getSection(),

                                      Asm->getFunctionBegin()));



  DwarfCompileUnit &CU = getOrCreateDwarfCompileUnit(SP->getUnit());



  // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
@@ -2532,8 +2529,9 @@ void DwarfDebug::emitDebugLocDWO() { 
      // offset_pair, so the implementations can't really share much since they

      // need to use different representations)

      // * as of October 2018, at least

      // Ideally/in v5, this could use SectionLabels to reuse existing addresses

      // in the address pool to minimize object size/relocations.

      //

      // In v5 (see emitLocList), this uses SectionLabels to reuse existing

      // addresses in the address pool to minimize object size/relocations.

      Asm->emitInt8(dwarf::DW_LLE_startx_length);

      unsigned idx = AddrPool.getIndex(Entry.Begin);

      Asm->EmitULEB128(idx);
@@ -3077,3 +3075,6 @@ uint16_t DwarfDebug::getDwarfVersion() const { 
const MCSymbol *DwarfDebug::getSectionLabel(const MCSection *S) {

  return SectionLabels.find(S)->second;

}

void DwarfDebug::insertSectionLabel(const MCSymbol *S) {

  SectionLabels.insert(std::make_pair(&S->getSection(), S));

}

llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h

+1 −0
Original line number Diff line number Diff line
@@ -768,6 +768,7 @@ public: 


  void addSectionLabel(const MCSymbol *Sym);

  const MCSymbol *getSectionLabel(const MCSection *S);

  void insertSectionLabel(const MCSymbol *S);



  static void emitDebugLocValue(const AsmPrinter &AP, const DIBasicType *BT,

                                const DbgValueLoc &Value,