Add support to properly reference private symbols on relocation entries.
Use proper relocation type to build relocations for JumpTables (rodata
sections).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76326 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/ELFWriter.cpp b/lib/CodeGen/ELFWriter.cpp
index 3e1645b..69220f9 100644
--- a/lib/CodeGen/ELFWriter.cpp
+++ b/lib/CodeGen/ELFWriter.cpp
@@ -296,8 +296,16 @@
}
}
- if (!GV->hasPrivateLinkage())
+ // Private symbols must never go to the symbol table.
+ unsigned SymIdx = 0;
+ if (GV->hasPrivateLinkage()) {
+ PrivateSyms.push_back(GblSym);
+ SymIdx = PrivateSyms.size()-1;
+ } else {
SymbolList.push_back(GblSym);
+ }
+
+ GblSymLookup[GV] = SymIdx;
}
void ELFWriter::EmitGlobalConstantStruct(const ConstantStruct *CVS,
@@ -394,20 +402,16 @@
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I) {
EmitGlobal(I);
- GblSymLookup[I] = 0;
}
// Emit all pending globals
// TODO: this should be done only for referenced symbols
for (SetVector<GlobalValue*>::const_iterator I = PendingGlobals.begin(),
E = PendingGlobals.end(); I != E; ++I) {
-
// No need to emit the symbol again
if (GblSymLookup.find(*I) != GblSymLookup.end())
continue;
-
EmitGlobal(*I);
- GblSymLookup[*I] = 0;
}
// Emit non-executable stack note
@@ -480,7 +484,8 @@
MRE = Relos.end(); MRI != MRE; ++MRI) {
MachineRelocation &MR = *MRI;
- // Offset from the start of the section containing the symbol
+ // Holds the relocatable field address as an offset from the
+ // beginning of the section where it lives
unsigned Offset = MR.getMachineCodeOffset();
// Symbol index in the symbol table
@@ -498,15 +503,34 @@
if (MR.isGlobalValue()) {
const GlobalValue *G = MR.getGlobalValue();
SymIdx = GblSymLookup[G];
- Addend = TEW->getAddendForRelTy(RelType);
+ if (G->hasPrivateLinkage()) {
+ // If the target uses a section offset in the relocation:
+ // SymIdx + Addend = section sym for global + section offset
+ unsigned SectionIdx = PrivateSyms[SymIdx]->SectionIdx;
+ Addend = PrivateSyms[SymIdx]->Value;
+ SymIdx = SectionList[SectionIdx]->getSymbolTableIndex();
+ } else {
+ Addend = TEW->getDefaultAddendForRelTy(RelType);
+ }
} else {
// Get the symbol index for the section symbol referenced
// by the relocation
unsigned SectionIdx = MR.getConstantVal();
- SymIdx = SectionList[SectionIdx]->Sym->SymTabIdx;
+ SymIdx = SectionList[SectionIdx]->getSymbolTableIndex();
Addend = (uint64_t)MR.getResultPointer();
}
+ // The target without addend on the relocation symbol must be
+ // patched in the relocation place itself to contain the addend
+ if (!HasRelA) {
+ if (TEW->getRelocationTySize(RelType) == 32)
+ S.fixWord32(Addend, Offset);
+ else if (TEW->getRelocationTySize(RelType) == 64)
+ S.fixWord64(Addend, Offset);
+ else
+ llvm_unreachable("don't know howto patch relocatable field");
+ }
+
// Get the relocation entry and emit to the relocation section
ELFRelocation Rel(Offset, SymIdx, RelType, HasRelA, Addend);
EmitRelocation(RelSec, Rel, HasRelA);