[PATCH] [lld][ELF] Change MaxAlignment to 2

[Shankar Kalpathi Easwaran]

Hi Bigcheese,

We would want to make sure the target handlers use the same alignment as how they are read. 

Setting the MaxAlignment to 2, makes it safe.

http://llvm-reviews.chandlerc.com/D1871

Files:
  lib/ReaderWriter/ELF/Hexagon/HexagonExecutableAtoms.h
  lib/ReaderWriter/ELF/Hexagon/HexagonRelocationHandler.h
  lib/ReaderWriter/ELF/Hexagon/HexagonSectionChunks.h
  lib/ReaderWriter/ELF/Hexagon/HexagonTargetHandler.h
  lib/ReaderWriter/ELF/PPC/PPCTargetHandler.h
  lib/ReaderWriter/ELF/X86/X86TargetHandler.h
  lib/ReaderWriter/ELF/X86_64/X86_64RelocationHandler.h
  lib/ReaderWriter/ELF/X86_64/X86_64TargetHandler.h
  test/elf/Hexagon/Inputs/libMaxAlignment.a
  test/elf/Hexagon/maxalignment.test

Index: lib/ReaderWriter/ELF/Hexagon/HexagonExecutableAtoms.h
===================================================================
--- lib/ReaderWriter/ELF/Hexagon/HexagonExecutableAtoms.h
+++ lib/ReaderWriter/ELF/Hexagon/HexagonExecutableAtoms.h
@@ -14,7 +14,7 @@
 
 namespace lld {
 namespace elf {
-typedef llvm::object::ELFType<llvm::support::little, 4, false> HexagonELFType;
+typedef llvm::object::ELFType<llvm::support::little, 2, false> HexagonELFType;
 class HexagonLinkingContext;
 
 template <class HexagonELFType> class HexagonRuntimeFile
Index: lib/ReaderWriter/ELF/Hexagon/HexagonRelocationHandler.h
===================================================================
--- lib/ReaderWriter/ELF/Hexagon/HexagonRelocationHandler.h
+++ lib/ReaderWriter/ELF/Hexagon/HexagonRelocationHandler.h
@@ -15,7 +15,6 @@
 
 namespace lld {
 namespace elf {
-typedef llvm::object::ELFType<llvm::support::little, 4, false> HexagonELFType;
 
 class HexagonLinkingContext;
 class HexagonTargetHandler;
Index: lib/ReaderWriter/ELF/Hexagon/HexagonSectionChunks.h
===================================================================
--- lib/ReaderWriter/ELF/Hexagon/HexagonSectionChunks.h
+++ lib/ReaderWriter/ELF/Hexagon/HexagonSectionChunks.h
@@ -13,7 +13,7 @@
 
 namespace lld {
 namespace elf {
-typedef llvm::object::ELFType<llvm::support::little, 4, false> HexagonELFType;
+typedef llvm::object::ELFType<llvm::support::little, 2, false> HexagonELFType;
 template <typename ELFT> class HexagonTargetLayout;
 class HexagonLinkingContext;
 
Index: lib/ReaderWriter/ELF/Hexagon/HexagonTargetHandler.h
===================================================================
--- lib/ReaderWriter/ELF/Hexagon/HexagonTargetHandler.h
+++ lib/ReaderWriter/ELF/Hexagon/HexagonTargetHandler.h
@@ -18,7 +18,7 @@
 
 namespace lld {
 namespace elf {
-typedef llvm::object::ELFType<llvm::support::little, 4, false> HexagonELFType;
+typedef llvm::object::ELFType<llvm::support::little, 2, false> HexagonELFType;
 class HexagonLinkingContext;
 
 /// \brief Handle Hexagon specific Atoms
Index: lib/ReaderWriter/ELF/PPC/PPCTargetHandler.h
===================================================================
--- lib/ReaderWriter/ELF/PPC/PPCTargetHandler.h
+++ lib/ReaderWriter/ELF/PPC/PPCTargetHandler.h
@@ -15,7 +15,7 @@
 
 namespace lld {
 namespace elf {
-typedef llvm::object::ELFType<llvm::support::big, 4, false> PPCELFType;
+typedef llvm::object::ELFType<llvm::support::big, 2, false> PPCELFType;
 class PPCLinkingContext;
 
 class PPCTargetRelocationHandler LLVM_FINAL
Index: lib/ReaderWriter/ELF/X86/X86TargetHandler.h
===================================================================
--- lib/ReaderWriter/ELF/X86/X86TargetHandler.h
+++ lib/ReaderWriter/ELF/X86/X86TargetHandler.h
@@ -15,7 +15,7 @@
 
 namespace lld {
 namespace elf {
-typedef llvm::object::ELFType<llvm::support::little, 4, false> X86ELFType;
+typedef llvm::object::ELFType<llvm::support::little, 2, false> X86ELFType;
 class X86LinkingContext;
 
 class X86TargetRelocationHandler LLVM_FINAL
Index: lib/ReaderWriter/ELF/X86_64/X86_64RelocationHandler.h
===================================================================
--- lib/ReaderWriter/ELF/X86_64/X86_64RelocationHandler.h
+++ lib/ReaderWriter/ELF/X86_64/X86_64RelocationHandler.h
@@ -15,7 +15,7 @@
 
 namespace lld {
 namespace elf {
-typedef llvm::object::ELFType<llvm::support::little, 8, true> X86_64ELFType;
+typedef llvm::object::ELFType<llvm::support::little, 2, true> X86_64ELFType;
 class X86_64LinkingContext;
 
 class X86_64TargetRelocationHandler LLVM_FINAL
Index: lib/ReaderWriter/ELF/X86_64/X86_64TargetHandler.h
===================================================================
--- lib/ReaderWriter/ELF/X86_64/X86_64TargetHandler.h
+++ lib/ReaderWriter/ELF/X86_64/X86_64TargetHandler.h
@@ -19,7 +19,7 @@
 
 namespace lld {
 namespace elf {
-typedef llvm::object::ELFType<llvm::support::little, 8, true> X86_64ELFType;
+typedef llvm::object::ELFType<llvm::support::little, 2, true> X86_64ELFType;
 class X86_64LinkingContext;
 
 class X86_64TargetHandler LLVM_FINAL
Index: test/elf/Hexagon/maxalignment.test
===================================================================
--- /dev/null
+++ test/elf/Hexagon/maxalignment.test
@@ -0,0 +1,8 @@
+# This tests that we lld is able to get the contentType properly for archives
+# when they intermittently get loaded at an address whose alignment is 2
+
+RUN: lld -flavor gnu -target hexagon --whole-archive %p/Inputs/libMaxAlignment.a \
+RUN: --noinhibit-exec -static -o %t
+RUN: llvm-nm %t | FileCheck %s
+
+CHECK: {{[0-9a-f]+}} D a
-------------- next part --------------
A non-text attachment was scrubbed...
Name: D1871.1.patch
Type: text/x-patch
Size: 4603 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20131009/d17e6770/attachment.bin>