From: Peter Collingbourne <peter@pcc.me.uk>
Date: Thu, 7 Jun 2018 00:02:07 +0000 (+0000)
Subject: llvm-readobj: fix printing number of relocations in Android packed format.
X-Git-Tag: android-x86-7.1-r4~155
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=032b3051e3a47c01d5fac64c152815aa98ca373d;p=android-x86%2Fexternal-llvm.git

llvm-readobj: fix printing number of relocations in Android packed format.

With '-elf-output-style=GNU -relocations', a header containing the number
of entries is printed before all the relocation entries in the section.
For Android packed format, we need to perform the unpacking first before
we can get the actual number of relocations in the section.

Patch by Rahul Chaudhry!

Differential Revision: https://reviews.llvm.org/D47800

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@334147 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/test/tools/llvm-readobj/elf-packed-relocs.test b/test/tools/llvm-readobj/elf-packed-relocs.test
index 49f6b36d3a4..4a59dafe8ef 100644
--- a/test/tools/llvm-readobj/elf-packed-relocs.test
+++ b/test/tools/llvm-readobj/elf-packed-relocs.test
@@ -14,6 +14,7 @@
 # LLVM1-NEXT: }
 
 # RUN: yaml2obj -docnum 1 %s | llvm-readobj -elf-output-style=GNU -relocations - | FileCheck --check-prefix=GNU1 %s
+# GNU1:      Relocation section '.rela.dyn' at offset 0x180 contains 8 entries:
 # GNU1:      0000000000001100  0000000000000008 R_X86_64_RELATIVE                 0
 # GNU1-NEXT: 0000000000001180  0000000000000008 R_X86_64_RELATIVE                 0
 # GNU1-NEXT: 0000000000001188  0000000100000001 R_X86_64_64            0000000000000000 sym1 + 0
@@ -60,6 +61,7 @@ Symbols:
 # LLVM2-NEXT: }
 
 # RUN: yaml2obj -docnum 2 %s | llvm-readobj -elf-output-style=GNU -relocations - | FileCheck --check-prefix=GNU2 %s
+# GNU2:      Relocation section '.rel.dyn' at offset 0xfc contains 10 entries:
 # GNU2:      00001008  00000101 R_386_32               00000000   sym1
 # GNU2-NEXT: 00001010  00000203 R_386_GOT32            00000000   sym2
 # GNU2-NEXT: 0000100c  00000008 R_386_RELATIVE
diff --git a/tools/llvm-readobj/ELFDumper.cpp b/tools/llvm-readobj/ELFDumper.cpp
index b6fed4f3c34..2492fa2acc2 100644
--- a/tools/llvm-readobj/ELFDumper.cpp
+++ b/tools/llvm-readobj/ELFDumper.cpp
@@ -2641,6 +2641,14 @@ template <class ELFT> void GNUStyle<ELFT>::printRelocations(const ELFO *Obj) {
     HasRelocSections = true;
     StringRef Name = unwrapOrError(Obj->getSectionName(&Sec));
     unsigned Entries = Sec.getEntityCount();
+    std::vector<Elf_Rela> AndroidRelas;
+    if (Sec.sh_type == ELF::SHT_ANDROID_REL ||
+        Sec.sh_type == ELF::SHT_ANDROID_RELA) {
+      // Android's packed relocation section needs to be unpacked first
+      // to get the actual number of entries.
+      AndroidRelas = unwrapOrError(Obj->android_relas(&Sec));
+      Entries = AndroidRelas.size();
+    }
     uintX_t Offset = Sec.sh_offset;
     OS << "\nRelocation section '" << Name << "' at offset 0x"
        << to_hexString(Offset, false) << " contains " << Entries
@@ -2665,7 +2673,7 @@ template <class ELFT> void GNUStyle<ELFT>::printRelocations(const ELFO *Obj) {
       break;
     case ELF::SHT_ANDROID_REL:
     case ELF::SHT_ANDROID_RELA:
-      for (const auto &R : unwrapOrError(Obj->android_relas(&Sec)))
+      for (const auto &R : AndroidRelas)
         printRelocation(Obj, SymTab, R, Sec.sh_type == ELF::SHT_ANDROID_RELA);
       break;
     }