Reland D114783/D115603 [ELF] Split scanRelocations into scanRelocations/postScanRelocations

(Fixed an issue about GOT on a copy relocated alias.)
(Fixed an issue about not creating r_addend=0 IRELATIVE for unreferenced non-preemptible ifunc.)

The idea is to make scanRelocations mark some actions are needed (GOT/PLT/etc)
and postpone the real work to postScanRelocations. It gives some flexibility:

* Make it feasible to support .plt.got (PR32938): we need to know whether GLOB_DAT and JUMP_SLOT are both needed.
* Make non-preemptible IFUNC handling slightly cleaner: avoid setting/clearing sym.gotInIgot
* -z nocopyrel: report all copy relocation places for one symbol
* Make GOT deduplication feasible
* Make parallel relocation scanning feasible (if we can avoid all stateful operations and make Symbol attributes atomic), but parallelism may not be the appealing choice

Since this patch moves a large chunk of code out of ELFT templates. My x86-64
executable is actually a few hundred bytes smaller.

For ppc32-ifunc-nonpreemptible-pic.s: I remove absolute relocation references to non-preemptible ifunc
because absolute relocation references are incorrect in -fpie mode.

Reviewed By: peter.smith, ikudrin

Differential Revision: https://reviews.llvm.org/D114783

1 files changed, 1 insertions, 1 deletions

diff --git a/lld/ELF/MapFile.cpp b/lld/ELF/MapFile.cpp
index b898dfda8a79..275983527538 100644
--- a/lld/ELF/MapFile.cpp
+++ b/lld/ELF/MapFile.cpp
@@ -58,7 +58,7 @@ static std::vector<Defined *> getSymbols() {
     for (Symbol *b : file->getSymbols())
       if (auto *dr = dyn_cast<Defined>(b))
         if (!dr->isSection() && dr->section && dr->section->isLive() &&
-            (dr->file == file || dr->needsPltAddr || dr->section->bss))
+            (dr->file == file || dr->needsCopy || dr->section->bss))
           v.push_back(dr);
   return v;
 }