[PATCH] D59594: [ELF] Change GOT*_FROM_END (relative to end(.got)) to GOTPLT* (start(.got.plt))

[Fangrui Song via Phabricator via llvm-commits]

MaskRay marked 2 inline comments as done.
MaskRay added inline comments.


================
Comment at: ELF/Arch/X86.cpp:196-197
     const uint8_t V[] = {
         0xff, 0xb3, 0x04, 0x00, 0x00, 0x00, // pushl GOTPLT+4(%ebx)
         0xff, 0xa3, 0x08, 0x00, 0x00, 0x00, // jmp *GOTPLT+8(%ebx)
         0x90, 0x90, 0x90, 0x90              // nop
----------------
ruiu wrote:
> Is this comment still correct? You are no longer modifying these instructions' operands, so I'm guessing they now have different operands.
`Ebx  = GotPlt` now so the 4 lines below can be deleted.


================
Comment at: test/ELF/plt-i686.s:148
 // DISASMSHARED-NEXT:  102f: 90 nop
-// DISASMSHARED-NEXT:  1030: ff a3 0c 30 00 00 jmpl *12300(%ebx)
+// DISASMSHARED:       bar at plt:
+// DISASMSHARED-NEXT:  1030: ff a3 0c 00 00 00 jmpl *12(%ebx)
----------------
`llvm/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp` cannot recognize our unusual GOT base (end(.got)). It is good now :)

      // The jmp instruction at the beginning of each PLT entry jumps to the
      // address of the base of the .got.plt section plus the immediate.
      uint32_t Imm = support::endian::read32le(PltContents.data() + Byte + 2);
      Result.push_back(
          std::make_pair(PltSectionVA + Byte, GotPltSectionVA + Imm));
      Byte += 6;



Repository:
  rLLD LLVM Linker

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D59594/new/

https://reviews.llvm.org/D59594