From 2197311c31ced1aff8d965294e190aaae1ac729b Mon Sep 17 00:00:00 2001
From: Rafael Espindola <rafael.espindola@gmail.com>
Date: Wed, 20 Jul 2016 20:19:58 +0000
Subject: [PATCH] Delete EhInputSection::getOffset.

We no longer need it for relocations in .eh_frame.

The only relocations that point to .eh_frame are the ones trying to
find the output .eh_frame.

This actually fixes a bug in the symbol value code. It was not
handling -1 as an indicator for a piece not being included in the
output.

llvm-svn: 276175
---
 lld/ELF/InputSection.cpp       | 20 ++++----------------
 lld/ELF/InputSection.h         |  4 ----
 lld/ELF/Relocations.cpp        |  1 -
 lld/test/ELF/eh-frame-marker.s | 12 ++++++++++++
 4 files changed, 16 insertions(+), 21 deletions(-)

diff --git a/lld/ELF/InputSection.cpp b/lld/ELF/InputSection.cpp
index 1cb1137..23c4f3d 100644
--- a/lld/ELF/InputSection.cpp
+++ b/lld/ELF/InputSection.cpp
@@ -68,7 +68,10 @@ typename ELFT::uint InputSectionBase<ELFT>::getOffset(uintX_t Offset) const {
   case Regular:
     return cast<InputSection<ELFT>>(this)->OutSecOff + Offset;
   case EHFrame:
-    return cast<EhInputSection<ELFT>>(this)->getOffset(Offset);
+    // The file crtbeginT.o has relocations pointing to the start of an empty
+    // .eh_frame that is known to be the first in the link. It does that to
+    // identify the start of the output .eh_frame.
+    return Offset;
   case Merge:
     return cast<MergeInputSection<ELFT>>(this)->getOffset(Offset);
   case MipsReginfo:
@@ -461,21 +464,6 @@ void EhInputSection<ELFT>::split() {
   }
 }
 
-template <class ELFT>
-typename ELFT::uint EhInputSection<ELFT>::getOffset(uintX_t Offset) const {
-  // The file crtbeginT.o has relocations pointing to the start of an empty
-  // .eh_frame that is known to be the first in the link. It does that to
-  // identify the start of the output .eh_frame. Handle this special case.
-  if (this->getSectionHdr()->sh_size == 0)
-    return Offset;
-  const SectionPiece *Piece = this->getSectionPiece(Offset);
-  if (Piece->OutputOff == size_t(-1))
-    return -1; // Not in the output
-
-  uintX_t Addend = Offset - Piece->InputOff;
-  return Piece->OutputOff + Addend;
-}
-
 static size_t findNull(ArrayRef<uint8_t> A, size_t EntSize) {
   // Optimize the common case.
   StringRef S((const char *)A.data(), A.size());
diff --git a/lld/ELF/InputSection.h b/lld/ELF/InputSection.h
index eabe5fb..107aa03 100644
--- a/lld/ELF/InputSection.h
+++ b/lld/ELF/InputSection.h
@@ -171,10 +171,6 @@ public:
   static bool classof(const InputSectionBase<ELFT> *S);
   void split();
 
-  // Translate an offset in the input section to an offset in the output
-  // section.
-  uintX_t getOffset(uintX_t Offset) const;
-
   // Relocation section that refer to this one.
   const Elf_Shdr *RelocSection = nullptr;
 };
diff --git a/lld/ELF/Relocations.cpp b/lld/ELF/Relocations.cpp
index 106cc7c..f0a2d17 100644
--- a/lld/ELF/Relocations.cpp
+++ b/lld/ELF/Relocations.cpp
@@ -557,7 +557,6 @@ static void scanRelocs(InputSectionBase<ELFT> &C, ArrayRef<RelTy> Rels) {
       if (PieceI->OutputOff == (uintX_t)-1)
         continue;
       Offset = PieceI->OutputOff + RI.r_offset - PieceI->InputOff;
-      assert(Offset == C.getOffset(RI.r_offset));
     } else {
       Offset = C.getOffset(RI.r_offset);
     }
diff --git a/lld/test/ELF/eh-frame-marker.s b/lld/test/ELF/eh-frame-marker.s
index a5de2a7..8c39515 100644
--- a/lld/test/ELF/eh-frame-marker.s
+++ b/lld/test/ELF/eh-frame-marker.s
@@ -1,6 +1,18 @@
 // RUN: llvm-mc %s -o %t.o -filetype=obj -triple=x86_64-pc-linux
 // RUN: ld.lld --eh-frame-hdr %t.o -o %t.so -shared
+// RUN: llvm-readobj -t -s %t.so | FileCheck %s
 // We used to crash on this.
+
+// CHECK:      Name: .eh_frame
+// CHECK-NEXT: Type: SHT_PROGBITS
+// CHECK-NEXT: Flags [
+// CHECK-NEXT:   SHF_ALLOC
+// CHECK-NEXT: ]
+// CHECK-NEXT: Address: 0x200
+
+// CHECK:      Name: foo
+// CHECK-NEXT: Value: 0x200
+
         .section .eh_frame
 foo:
         .long 0
-- 
2.7.4