From dfc7200b1808433f60e02cb6773a2c4f6b699df1 Mon Sep 17 00:00:00 2001
From: Rafael Espindola <rafael.espindola@gmail.com>
Date: Mon, 28 Sep 2015 18:29:47 +0000
Subject: [PATCH] Add support for local absolute symbols.

llvm-svn: 248726
---
 lld/ELF/OutputSections.cpp | 27 +++++++++++++++------------
 lld/test/elf2/local.s      | 12 +++++++++++-
 2 files changed, 26 insertions(+), 13 deletions(-)

diff --git a/lld/ELF/OutputSections.cpp b/lld/ELF/OutputSections.cpp
index 07e79b1adf18..6e1359e5f6cf 100644
--- a/lld/ELF/OutputSections.cpp
+++ b/lld/ELF/OutputSections.cpp
@@ -403,24 +403,27 @@ template <class ELFT> void SymbolTableSection<ELFT>::writeTo(uint8_t *Buf) {
       Elf_Sym_Range Syms = File.getLocalSymbols();
       for (const Elf_Sym &Sym : Syms) {
         auto *ESym = reinterpret_cast<Elf_Sym *>(Buf);
-        uint32_t SecIndex = Sym.st_shndx;
         ErrorOr<StringRef> SymName = Sym.getName(File.getStringTable());
         if (SymName && !shouldKeepInSymtab(*SymName))
           continue;
         ESym->st_name = (SymName) ? StrTabSec.getFileOff(*SymName) : 0;
         ESym->st_size = Sym.st_size;
         ESym->setBindingAndType(Sym.getBinding(), Sym.getType());
-        if (SecIndex == SHN_XINDEX)
-          SecIndex = File.getObj().getExtendedSymbolTableIndex(
-              &Sym, File.getSymbolTable(), File.getSymbolTableShndx());
-        ArrayRef<InputSection<ELFT> *> Sections = File.getSections();
-        const InputSection<ELFT> *Section = Sections[SecIndex];
-        assert(Section != nullptr);
-        const OutputSection<ELFT> *Out = Section->getOutputSection();
-        assert(Out != nullptr);
-        ESym->st_shndx = Out->getSectionIndex();
-        ESym->st_value =
-            Out->getVA() + Section->getOutputSectionOff() + Sym.st_value;
+        uint32_t SecIndex = Sym.st_shndx;
+        uintX_t VA = Sym.st_value;
+        if (SecIndex == SHN_ABS) {
+          ESym->st_shndx = SHN_ABS;
+        } else {
+          if (SecIndex == SHN_XINDEX)
+            SecIndex = File.getObj().getExtendedSymbolTableIndex(
+                &Sym, File.getSymbolTable(), File.getSymbolTableShndx());
+          ArrayRef<InputSection<ELFT> *> Sections = File.getSections();
+          const InputSection<ELFT> *Section = Sections[SecIndex];
+          const OutputSection<ELFT> *Out = Section->getOutputSection();
+          ESym->st_shndx = Out->getSectionIndex();
+          VA += Out->getVA() + Section->getOutputSectionOff();
+        }
+        ESym->st_value = VA;
         Buf += sizeof(Elf_Sym);
       }
     }
diff --git a/lld/test/elf2/local.s b/lld/test/elf2/local.s
index 3aa9642c21a2..8c09264ff765 100644
--- a/lld/test/elf2/local.s
+++ b/lld/test/elf2/local.s
@@ -14,7 +14,7 @@
 // CHECK-NEXT:     Offset:
 // CHECK-NEXT:     Size:
 // CHECK-NEXT:     Link:
-// CHECK-NEXT:     Info: 4
+// CHECK-NEXT:     Info: 5
 
 // CHECK: Symbols [
 // CHECK-NEXT:   Symbol {
@@ -27,6 +27,15 @@
 // CHECK-NEXT:     Section: Undefined
 // CHECK-NEXT:   }
 // CHECK-NEXT:   Symbol {
+// CHECK-NEXT:     Name: abs
+// CHECK-NEXT:     Value: 0x2A
+// CHECK-NEXT:     Size: 0
+// CHECK-NEXT:     Binding: Local
+// CHECK-NEXT:     Type: None
+// CHECK-NEXT:     Other: 0
+// CHECK-NEXT:     Section: Absolute
+// CHECK-NEXT:   }
+// CHECK-NEXT:   Symbol {
 // CHECK-NEXT:     Name: blah
 // CHECK-NEXT:     Value: 0x11000
 // CHECK-NEXT:     Size: 0
@@ -70,3 +79,4 @@ _start:
 blah:
 foo:
 goo:
+abs = 42