Avoid explicit relocation sorting most of the time.
These days relocations are created and stored in a deterministic way.
The order they are created is also suitable for the .o file, so we don't
need an explicit sort.
The last remaining exception is MIPS.
llvm-svn: 255902
diff --git a/llvm/lib/MC/ELFObjectWriter.cpp b/llvm/lib/MC/ELFObjectWriter.cpp
index a92b049..e6552be 100644
--- a/llvm/lib/MC/ELFObjectWriter.cpp
+++ b/llvm/lib/MC/ELFObjectWriter.cpp
@@ -1046,28 +1046,17 @@
WriteWord(EntrySize); // sh_entsize
}
-// ELF doesn't require relocations to be in any order. We sort by the Offset,
-// just to match gnu as for easier comparison. The use type is an arbitrary way
-// of making the sort deterministic.
-static int cmpRel(const ELFRelocationEntry *AP, const ELFRelocationEntry *BP) {
- const ELFRelocationEntry &A = *AP;
- const ELFRelocationEntry &B = *BP;
- if (A.Offset != B.Offset)
- return B.Offset - A.Offset;
- if (B.Type != A.Type)
- return A.Type - B.Type;
- llvm_unreachable("ELFRelocs might be unstable!");
- return 0;
-}
-
void ELFObjectWriter::writeRelocations(const MCAssembler &Asm,
const MCSectionELF &Sec) {
std::vector<ELFRelocationEntry> &Relocs = Relocations[&Sec];
- array_pod_sort(Relocs.begin(), Relocs.end(), cmpRel);
+ // We record relocations by pushing to the end of a vector. Reverse the vector
+ // to get the relocations in the order they were created.
+ // In most cases that is not important, but it can be for special sections
+ // (.eh_frame) or specific relocations (TLS optimizations on SystemZ).
+ std::reverse(Relocs.begin(), Relocs.end());
- // Sort the relocation entries. Most targets just sort by Offset, but some
- // (e.g., MIPS) have additional constraints.
+ // Sort the relocation entries. MIPS needs this.
TargetObjectWriter->sortRelocs(Asm, Relocs);
for (unsigned i = 0, e = Relocs.size(); i != e; ++i) {