Implement unique sections with an unique ID.

This allows the compiler/assembly programmer to switch back to a
section. This in turn fixes the bootstrap failure on powerpc (tested
on gcc110) without changing the ppc codegen at all.

I will try to cleanup the various getELFSection overloads in a  followup patch.
Just using a default argument now would lead to ambiguities.

llvm-svn: 234099

1 files changed, 14 insertions, 7 deletions

diff --git a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
index bcf2aa72c4b..5b795e4b37b 100644
--- a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -245,9 +245,11 @@ static StringRef getSectionPrefixForGlobal(SectionKind Kind) {
   return ".data.rel.ro";
 }
 
-static const MCSectionELF *selectELFSectionForGlobal(
-    MCContext &Ctx, const GlobalValue *GV, SectionKind Kind, Mangler &Mang,
-    const TargetMachine &TM, bool EmitUniqueSection, unsigned Flags) {
+static const MCSectionELF *
+selectELFSectionForGlobal(MCContext &Ctx, const GlobalValue *GV,
+                          SectionKind Kind, Mangler &Mang,
+                          const TargetMachine &TM, bool EmitUniqueSection,
+                          unsigned Flags, unsigned *NextUniqueID) {
   unsigned EntrySize = 0;
   if (Kind.isMergeableCString()) {
     if (Kind.isMergeable2ByteCString()) {
@@ -297,9 +299,13 @@ static const MCSectionELF *selectELFSectionForGlobal(
     Name.push_back('.');
     TM.getNameWithPrefix(Name, GV, Mang, true);
   }
+  unsigned UniqueID = ~0;
+  if (EmitUniqueSection && !UniqueSectionNames) {
+    UniqueID = *NextUniqueID;
+    (*NextUniqueID)++;
+  }
   return Ctx.getELFSection(Name, getELFSectionType(Name, Kind), Flags,
-                           EntrySize, Group,
-                           EmitUniqueSection && !UniqueSectionNames);
+                           EntrySize, Group, UniqueID);
 }
 
 const MCSection *TargetLoweringObjectFileELF::SelectSectionForGlobal(
@@ -319,7 +325,7 @@ const MCSection *TargetLoweringObjectFileELF::SelectSectionForGlobal(
   EmitUniqueSection |= GV->hasComdat();
 
   return selectELFSectionForGlobal(getContext(), GV, Kind, Mang, TM,
-                                   EmitUniqueSection, Flags);
+                                   EmitUniqueSection, Flags, &NextUniqueID);
 }
 
 const MCSection *TargetLoweringObjectFileELF::getSectionForJumpTable(
@@ -332,7 +338,8 @@ const MCSection *TargetLoweringObjectFileELF::getSectionForJumpTable(
     return ReadOnlySection;
 
   return selectELFSectionForGlobal(getContext(), &F, SectionKind::getReadOnly(),
-                                   Mang, TM, EmitUniqueSection, ELF::SHF_ALLOC);
+                                   Mang, TM, EmitUniqueSection, ELF::SHF_ALLOC,
+                                   &NextUniqueID);
 }
 
 bool TargetLoweringObjectFileELF::shouldPutJumpTableInFunctionSection(