Merging r195148:

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r195148 | rafael | 2013-11-19 11:52:52 -0800 (Tue, 19 Nov 2013) | 15 lines

Support multiple COFF sections with the same name but different COMDAT.

This is the first step to fix pr17918.

It extends the .section directive a bit, inspired by what the ELF one looks
like. The problem with using linkonce is that given

.section foo
.linkonce....

.section foo
.linkonce

we would already have switched sections when getting to .linkonce. The cleanest
solution seems to be to add the comdat information in the .section itself.
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_34@195822 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 31 insertions, 13 deletions

diff --git a/lib/MC/MCContext.cpp b/lib/MC/MCContext.cpp
index 67904f6f74..3b45d1670d 100644
--- a/lib/MC/MCContext.cpp
+++ b/lib/MC/MCContext.cpp
@@ -34,8 +34,7 @@ typedef std::pair<std::string, std::string> SectionGroupPair;
 
 typedef StringMap<const MCSectionMachO*> MachOUniqueMapTy;
 typedef std::map<SectionGroupPair, const MCSectionELF *> ELFUniqueMapTy;
-typedef StringMap<const MCSectionCOFF*> COFFUniqueMapTy;
-
+typedef std::map<SectionGroupPair, const MCSectionCOFF *> COFFUniqueMapTy;
 
 MCContext::MCContext(const MCAsmInfo *mai, const MCRegisterInfo *mri,
                      const MCObjectFileInfo *mofi, const SourceMgr *mgr,
@@ -280,32 +279,51 @@ const MCSectionELF *MCContext::CreateELFGroupSection() {
   return Result;
 }
 
-const MCSectionCOFF *MCContext::getCOFFSection(StringRef Section,
-                                               unsigned Characteristics,
-                                               SectionKind Kind, int Selection,
-                                               const MCSectionCOFF *Assoc) {
+const MCSectionCOFF *
+MCContext::getCOFFSection(StringRef Section, unsigned Characteristics,
+                          SectionKind Kind, StringRef COMDATSymName,
+                          int Selection, const MCSectionCOFF *Assoc) {
   if (COFFUniquingMap == 0)
     COFFUniquingMap = new COFFUniqueMapTy();
   COFFUniqueMapTy &Map = *(COFFUniqueMapTy*)COFFUniquingMap;
 
   // Do the lookup, if we have a hit, return it.
-  StringMapEntry<const MCSectionCOFF*> &Entry = Map.GetOrCreateValue(Section);
-  if (Entry.getValue()) return Entry.getValue();
 
-  MCSectionCOFF *Result = new (*this) MCSectionCOFF(Entry.getKey(),
-                                                    Characteristics,
-                                                    Selection, Assoc, Kind);
+  SectionGroupPair P(Section, COMDATSymName);
+  std::pair<COFFUniqueMapTy::iterator, bool> Entry =
+      Map.insert(std::make_pair(P, (MCSectionCOFF *)0));
+  COFFUniqueMapTy::iterator Iter = Entry.first;
+  if (!Entry.second)
+    return Iter->second;
+
+  const MCSymbol *COMDATSymbol = NULL;
+  if (!COMDATSymName.empty())
+    COMDATSymbol = GetOrCreateSymbol(COMDATSymName);
+
+  MCSectionCOFF *Result =
+      new (*this) MCSectionCOFF(Iter->first.first, Characteristics,
+                                COMDATSymbol, Selection, Assoc, Kind);
 
-  Entry.setValue(Result);
+  Iter->second = Result;
   return Result;
 }
 
+const MCSectionCOFF *
+MCContext::getCOFFSection(StringRef Section, unsigned Characteristics,
+                          SectionKind Kind) {
+  return getCOFFSection(Section, Characteristics, Kind, "", 0);
+}
+
 const MCSectionCOFF *MCContext::getCOFFSection(StringRef Section) {
   if (COFFUniquingMap == 0)
     COFFUniquingMap = new COFFUniqueMapTy();
   COFFUniqueMapTy &Map = *(COFFUniqueMapTy*)COFFUniquingMap;
 
-  return Map.lookup(Section);
+  SectionGroupPair P(Section, "");
+  COFFUniqueMapTy::iterator Iter = Map.find(P);
+  if (Iter == Map.end())
+    return 0;
+  return Iter->second;
 }
 
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