Use common range handling for the CU's ranges

This generalizes the range handling for ranges in both the skeleton and
full unit, laying the foundation for the addition of more ranges (rather
than just the CU's special case) in the skeleton CU with fission+gmlt.

llvm-svn: 221202

lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp

@@ -372,40 +372,46 @@ void DwarfCompileUnit::addSectionDelta(DIE &Die, dwarf::Attribute Attribute,
                Value);
 }
 
-void
-DwarfCompileUnit::addScopeRangeList(DIE &ScopeDIE,
-                                    const SmallVectorImpl<InsnRange> &Range) {
+void DwarfCompileUnit::addScopeRangeList(DIE &ScopeDIE,
+                                         SmallVector<RangeSpan, 2> Range) {
   // Emit offset in .debug_range as a relocatable label. emitDIE will handle
   // emitting it appropriately.
-  MCSymbol *RangeSym =
-      Asm->GetTempSymbol("debug_ranges", DD->getNextRangeNumber());
-
   auto *RangeSectionSym = DD->getRangeSectionSym();
 
+  RangeSpanList List(
+      Asm->GetTempSymbol("debug_ranges", DD->getNextRangeNumber()),
+      std::move(Range));
+
   // Under fission, ranges are specified by constant offsets relative to the
   // CU's DW_AT_GNU_ranges_base.
-  if (DD->useSplitDwarf())
-    addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, RangeSym, RangeSectionSym);
+  if (isDwoUnit())
+    addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, List.getSym(),
+                    RangeSectionSym);
   else
-    addSectionLabel(ScopeDIE, dwarf::DW_AT_ranges, RangeSym, RangeSectionSym);
-
-  RangeSpanList List(RangeSym);
-  for (const InsnRange &R : Range)
-    List.addRange(RangeSpan(DD->getLabelBeforeInsn(R.first),
-                            DD->getLabelAfterInsn(R.second)));
+    addSectionLabel(ScopeDIE, dwarf::DW_AT_ranges, List.getSym(),
+                    RangeSectionSym);
 
   // Add the range list to the set of ranges to be emitted.
   (Skeleton ? Skeleton : this)->CURangeLists.push_back(std::move(List));
 }
 
+void DwarfCompileUnit::attachRangesOrLowHighPC(
+    DIE &Die, SmallVector<RangeSpan, 2> Ranges) {
+  if (Ranges.size() == 1) {
+    const auto &single = Ranges.front();
+    attachLowHighPC(Die, single.getStart(), single.getEnd());
+  } else
+    addScopeRangeList(Die, std::move(Ranges));
+}
+
 void DwarfCompileUnit::attachRangesOrLowHighPC(
     DIE &Die, const SmallVectorImpl<InsnRange> &Ranges) {
-  assert(!Ranges.empty());
-  if (Ranges.size() == 1)
-    attachLowHighPC(Die, DD->getLabelBeforeInsn(Ranges.front().first),
-                    DD->getLabelAfterInsn(Ranges.front().second));
-  else
-    addScopeRangeList(Die, Ranges);
+  SmallVector<RangeSpan, 2> List;
+  List.reserve(Ranges.size());
+  for (const InsnRange &R : Ranges)
+    List.push_back(RangeSpan(DD->getLabelBeforeInsn(R.first),
+                             DD->getLabelAfterInsn(R.second)));
+  attachRangesOrLowHighPC(Die, std::move(List));
 }
 
 // This scope represents inlined body of a function. Construct DIE to

lib/CodeGen/AsmPrinter/DwarfCompileUnit.h

@@ -53,7 +53,7 @@ class DwarfCompileUnit : public DwarfUnit {
   SmallVector<RangeSpanList, 1> CURangeLists;
 
   // List of ranges for a given compile unit.
-  SmallVector<RangeSpan, 1> CURanges;
+  SmallVector<RangeSpan, 2> CURanges;
 
   // The base address of this unit, if any. Used for relative references in
   // ranges/locs.
@@ -121,12 +121,12 @@ public:
 
   /// \brief A helper function to construct a RangeSpanList for a given
   /// lexical scope.
-  void addScopeRangeList(DIE &ScopeDIE,
-                         const SmallVectorImpl<InsnRange> &Range);
+  void addScopeRangeList(DIE &ScopeDIE, SmallVector<RangeSpan, 2> Range);
+
+  void attachRangesOrLowHighPC(DIE &D, SmallVector<RangeSpan, 2> Ranges);
 
   void attachRangesOrLowHighPC(DIE &D,
                                const SmallVectorImpl<InsnRange> &Ranges);
-
   /// \brief This scope represents inlined body of a function. Construct
   /// DIE to represent this concrete inlined copy of the function.
   std::unique_ptr<DIE> constructInlinedScopeDIE(LexicalScope *Scope);
@@ -237,6 +237,7 @@ public:
 
   /// getRanges - Get the list of ranges for this unit.
   const SmallVectorImpl<RangeSpan> &getRanges() const { return CURanges; }
+  SmallVector<RangeSpan, 2> takeRanges() { return std::move(CURanges); }
 
   void setBaseAddress(const MCSymbol *Base) { BaseAddress = Base; }
   const MCSymbol *getBaseAddress() const { return BaseAddress; }

lib/CodeGen/AsmPrinter/DwarfDebug.cpp

@@ -578,23 +578,16 @@ void DwarfDebug::finalizeModuleInfo() {
     // .subsections_via_symbols in mach-o. This would mean turning on
     // ranges for all subprogram DIEs for mach-o.
     DwarfCompileUnit &U = SkCU ? *SkCU : TheCU;
-    unsigned NumRanges = TheCU.getRanges().size();
-    if (NumRanges) {
-      if (NumRanges > 1) {
-        U.addSectionLabel(U.getUnitDie(), dwarf::DW_AT_ranges,
-                          Asm->GetTempSymbol("cu_ranges", U.getUniqueID()),
-                          DwarfDebugRangeSectionSym);
-
+    if (unsigned NumRanges = TheCU.getRanges().size()) {
+      if (NumRanges > 1)
         // A DW_AT_low_pc attribute may also be specified in combination with
         // DW_AT_ranges to specify the default base address for use in
         // location lists (see Section 2.6.2) and range lists (see Section
         // 2.17.3).
         U.addUInt(U.getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr, 0);
-      } else {
-        const RangeSpan &Range = TheCU.getRanges().back();
-        TheCU.setBaseAddress(Range.getStart());
-        U.attachLowHighPC(U.getUnitDie(), Range.getStart(), Range.getEnd());
-      }
+      else
+        TheCU.setBaseAddress(TheCU.getRanges().front().getStart());
+      U.attachRangesOrLowHighPC(U.getUnitDie(), TheCU.takeRanges());
     }
   }
 
@@ -1787,7 +1780,6 @@ void DwarfDebug::emitDebugLoc() {
   for (const auto &DebugLoc : DotDebugLocEntries) {
     Asm->OutStreamer.EmitLabel(DebugLoc.Label);
     const DwarfCompileUnit *CU = DebugLoc.CU;
-    assert(!CU->getRanges().empty());
     for (const auto &Entry : DebugLoc.List) {
       // Set up the range. This range is relative to the entry point of the
       // compile unit. This is a hard coded 0 for low_pc when we're emitting
@@ -2015,23 +2007,6 @@ void DwarfDebug::emitDebugRanges() {
       Asm->OutStreamer.EmitIntValue(0, Size);
       Asm->OutStreamer.EmitIntValue(0, Size);
     }
-
-    // Now emit a range for the CU itself.
-    if (TheCU->getRanges().size() > 1) {
-      Asm->OutStreamer.EmitLabel(
-          Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
-      for (const RangeSpan &Range : TheCU->getRanges()) {
-        const MCSymbol *Begin = Range.getStart();
-        const MCSymbol *End = Range.getEnd();
-        assert(Begin && "Range without a begin symbol?");
-        assert(End && "Range without an end symbol?");
-        Asm->OutStreamer.EmitSymbolValue(Begin, Size);
-        Asm->OutStreamer.EmitSymbolValue(End, Size);
-      }
-      // And terminate the list with two 0 values.
-      Asm->OutStreamer.EmitIntValue(0, Size);
-      Asm->OutStreamer.EmitIntValue(0, Size);
-    }
   }
 }
 

lib/CodeGen/AsmPrinter/DwarfUnit.h

@@ -55,7 +55,8 @@ private:
   SmallVector<RangeSpan, 2> Ranges;
 
 public:
-  RangeSpanList(MCSymbol *Sym) : RangeSym(Sym) {}
+  RangeSpanList(MCSymbol *Sym, SmallVector<RangeSpan, 2> Ranges)
+      : RangeSym(Sym), Ranges(std::move(Ranges)) {}
   MCSymbol *getSym() const { return RangeSym; }
   const SmallVectorImpl<RangeSpan> &getRanges() const { return Ranges; }
   void addRange(RangeSpan Range) { Ranges.push_back(Range); }