[lld] r289642 - [ELF] Accept first SHT_ARM_ATTRIBUTES section
Peter Smith via llvm-commits
llvm-commits at lists.llvm.org
Wed Dec 14 02:36:12 PST 2016
Author: psmith
Date: Wed Dec 14 04:36:12 2016
New Revision: 289642
URL: http://llvm.org/viewvc/llvm-project?rev=289642&view=rev
Log:
[ELF] Accept first SHT_ARM_ATTRIBUTES section
The eglibc library, as used by Ubuntu 14.04 requires the presence of an
SHT_ARM_ATTRIBUTES section in for the purposes of checking hard/soft float
compatibility when dlopen() is used. Unfortunately when the section is not
present dlopen() fails with a generic could not find file message.
This change makes lld keep the first .ARM.attributes section that it
encounters and propagates it to the output. This is not a complete
SHT_ARM_ATTRIBUTES implementation, that would involve reading the contents
of the section and joining each individual attribute. It should suffice
for a homogenous build all libraries and executables on the same system
with a compatible set of command line options.
Differential revision: https://reviews.llvm.org/D27718
Added:
lld/trunk/test/ELF/Inputs/arm-attributes1.s
- copied, changed from r289641, lld/trunk/test/ELF/arm-attributes-remove.s
lld/trunk/test/ELF/arm-attributes.s (with props)
Removed:
lld/trunk/test/ELF/arm-attributes-remove.s
Modified:
lld/trunk/ELF/InputFiles.cpp
lld/trunk/ELF/SyntheticSections.h
Modified: lld/trunk/ELF/InputFiles.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/InputFiles.cpp?rev=289642&r1=289641&r2=289642&view=diff
==============================================================================
--- lld/trunk/ELF/InputFiles.cpp (original)
+++ lld/trunk/ELF/InputFiles.cpp Wed Dec 14 04:36:12 2016
@@ -14,6 +14,7 @@
#include "LinkerScript.h"
#include "SymbolTable.h"
#include "Symbols.h"
+#include "SyntheticSections.h"
#include "lld/Support/Memory.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Bitcode/BitcodeReader.h"
@@ -336,8 +337,14 @@ elf::ObjectFile<ELFT>::createInputSectio
switch (Sec.sh_type) {
case SHT_ARM_ATTRIBUTES:
- // FIXME: ARM meta-data section. At present attributes are ignored,
- // they can be used to reason about object compatibility.
+ // FIXME: ARM meta-data section. Retain the first attribute section
+ // we see. The eglibc ARM dynamic loaders require the presence of an
+ // attribute section for dlopen to work.
+ // In a full implementation we would merge all attribute sections.
+ if (In<ELFT>::ARMAttributes == nullptr) {
+ In<ELFT>::ARMAttributes = make<InputSection<ELFT>>(this, &Sec, Name);
+ return In<ELFT>::ARMAttributes;
+ }
return &InputSection<ELFT>::Discarded;
case SHT_RELA:
case SHT_REL: {
Modified: lld/trunk/ELF/SyntheticSections.h
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/SyntheticSections.h?rev=289642&r1=289641&r2=289642&view=diff
==============================================================================
--- lld/trunk/ELF/SyntheticSections.h (original)
+++ lld/trunk/ELF/SyntheticSections.h Wed Dec 14 04:36:12 2016
@@ -667,6 +667,7 @@ template <class ELFT> MergeInputSection<
// Linker generated sections which can be used as inputs.
template <class ELFT> struct In {
+ static InputSection<ELFT> *ARMAttributes;
static BuildIdSection<ELFT> *BuildId;
static InputSection<ELFT> *Common;
static DynamicSection<ELFT> *Dynamic;
@@ -695,6 +696,7 @@ template <class ELFT> struct In {
static VersionNeedSection<ELFT> *VerNeed;
};
+template <class ELFT> InputSection<ELFT> *In<ELFT>::ARMAttributes;
template <class ELFT> BuildIdSection<ELFT> *In<ELFT>::BuildId;
template <class ELFT> InputSection<ELFT> *In<ELFT>::Common;
template <class ELFT> DynamicSection<ELFT> *In<ELFT>::Dynamic;
Copied: lld/trunk/test/ELF/Inputs/arm-attributes1.s (from r289641, lld/trunk/test/ELF/arm-attributes-remove.s)
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/Inputs/arm-attributes1.s?p2=lld/trunk/test/ELF/Inputs/arm-attributes1.s&p1=lld/trunk/test/ELF/arm-attributes-remove.s&r1=289641&r2=289642&rev=289642&view=diff
==============================================================================
--- lld/trunk/test/ELF/arm-attributes-remove.s (original)
+++ lld/trunk/test/ELF/Inputs/arm-attributes1.s Wed Dec 14 04:36:12 2016
@@ -1,20 +1,4 @@
-// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %s -o %t.o
-// RUN: ld.lld %t.o -o %t
-// RUN: llvm-readobj -s %t | FileCheck %s
-// RUN: ld.lld %t.o -shared -o %t2
-// RUN: llvm-readobj -s %t2 | FileCheck %s
-// RUN: ld.lld %t.o -r -o %t3
-// RUN: llvm-readobj -s %t3 | FileCheck %s
-
-// The .ARM.attributes section should be removed from executables and
-// shared objects.
-
-// At present we remove it from the -r object output as well which isn't ideal.
-// Unfortunately combining per-object attributes cannot be safely done by just
-// concatentation of input sections.
-
-// CHECK-NOT: Name: .ARM.attributes
-// REQUIRES: arm
+// Input that generates an object with a populated SHT_ARM_ATTRIBUTES section
.text
.syntax unified
.eabi_attribute 67, "2.09" @ Tag_conformance
@@ -38,8 +22,8 @@
.eabi_attribute 26, 2 @ Tag_ABI_enum_size
.eabi_attribute 14, 0 @ Tag_ABI_PCS_R9_use
.eabi_attribute 68, 1 @ Tag_Virtualization_use
- .globl _start
+ .globl func
.p2align 2
- .type _start,%function
-_start:
+ .type func,%function
+func:
bx lr
Removed: lld/trunk/test/ELF/arm-attributes-remove.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/arm-attributes-remove.s?rev=289641&view=auto
==============================================================================
--- lld/trunk/test/ELF/arm-attributes-remove.s (original)
+++ lld/trunk/test/ELF/arm-attributes-remove.s (removed)
@@ -1,45 +0,0 @@
-// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %s -o %t.o
-// RUN: ld.lld %t.o -o %t
-// RUN: llvm-readobj -s %t | FileCheck %s
-// RUN: ld.lld %t.o -shared -o %t2
-// RUN: llvm-readobj -s %t2 | FileCheck %s
-// RUN: ld.lld %t.o -r -o %t3
-// RUN: llvm-readobj -s %t3 | FileCheck %s
-
-// The .ARM.attributes section should be removed from executables and
-// shared objects.
-
-// At present we remove it from the -r object output as well which isn't ideal.
-// Unfortunately combining per-object attributes cannot be safely done by just
-// concatentation of input sections.
-
-// CHECK-NOT: Name: .ARM.attributes
-// REQUIRES: arm
- .text
- .syntax unified
- .eabi_attribute 67, "2.09" @ Tag_conformance
- .cpu cortex-a8
- .eabi_attribute 6, 10 @ Tag_CPU_arch
- .eabi_attribute 7, 65 @ Tag_CPU_arch_profile
- .eabi_attribute 8, 1 @ Tag_ARM_ISA_use
- .eabi_attribute 9, 2 @ Tag_THUMB_ISA_use
- .fpu neon
- .eabi_attribute 15, 1 @ Tag_ABI_PCS_RW_data
- .eabi_attribute 16, 1 @ Tag_ABI_PCS_RO_data
- .eabi_attribute 17, 2 @ Tag_ABI_PCS_GOT_use
- .eabi_attribute 20, 1 @ Tag_ABI_FP_denormal
- .eabi_attribute 21, 1 @ Tag_ABI_FP_exceptions
- .eabi_attribute 23, 3 @ Tag_ABI_FP_number_model
- .eabi_attribute 34, 1 @ Tag_CPU_unaligned_access
- .eabi_attribute 24, 1 @ Tag_ABI_align_needed
- .eabi_attribute 25, 1 @ Tag_ABI_align_preserved
- .eabi_attribute 38, 1 @ Tag_ABI_FP_16bit_format
- .eabi_attribute 18, 4 @ Tag_ABI_PCS_wchar_t
- .eabi_attribute 26, 2 @ Tag_ABI_enum_size
- .eabi_attribute 14, 0 @ Tag_ABI_PCS_R9_use
- .eabi_attribute 68, 1 @ Tag_Virtualization_use
- .globl _start
- .p2align 2
- .type _start,%function
-_start:
- bx lr
Added: lld/trunk/test/ELF/arm-attributes.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/arm-attributes.s?rev=289642&view=auto
==============================================================================
--- lld/trunk/test/ELF/arm-attributes.s (added)
+++ lld/trunk/test/ELF/arm-attributes.s Wed Dec 14 04:36:12 2016
@@ -0,0 +1,183 @@
+// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %S/Inputs/arm-attributes1.s -o %t1.o
+// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %s -o %t2.o
+
+// RUN: ld.lld %t1.o %t2.o -o %t
+// RUN: llvm-readobj -arm-attributes %t | FileCheck %s
+// RUN: ld.lld %t1.o %t2.o -shared -o %t2
+// RUN: llvm-readobj -arm-attributes %t2 | FileCheck %s
+// RUN: ld.lld %t1.o %t2.o -r -o %t3
+// RUN: llvm-readobj -arm-attributes %t3 | FileCheck %s
+// REQUIRES: arm
+
+// Check that we retain only 1 SHT_ARM_ATTRIBUTES section. At present we do not
+// try and merge or use the contents of SHT_ARM_ATTRIBUTES sections. We just
+// pass the first one through.
+ .text
+ .syntax unified
+ .eabi_attribute 67, "2.09" @ Tag_conformance
+ .cpu cortex-a8
+ .eabi_attribute 6, 10 @ Tag_CPU_arch
+ .eabi_attribute 7, 65 @ Tag_CPU_arch_profile
+ .eabi_attribute 8, 1 @ Tag_ARM_ISA_use
+ .eabi_attribute 9, 2 @ Tag_THUMB_ISA_use
+ .fpu neon
+ .eabi_attribute 15, 1 @ Tag_ABI_PCS_RW_data
+ .eabi_attribute 16, 1 @ Tag_ABI_PCS_RO_data
+ .eabi_attribute 17, 2 @ Tag_ABI_PCS_GOT_use
+ .eabi_attribute 20, 1 @ Tag_ABI_FP_denormal
+ .eabi_attribute 21, 1 @ Tag_ABI_FP_exceptions
+ .eabi_attribute 23, 3 @ Tag_ABI_FP_number_model
+ .eabi_attribute 34, 1 @ Tag_CPU_unaligned_access
+ .eabi_attribute 24, 1 @ Tag_ABI_align_needed
+ .eabi_attribute 25, 1 @ Tag_ABI_align_preserved
+ .eabi_attribute 38, 1 @ Tag_ABI_FP_16bit_format
+ .eabi_attribute 18, 4 @ Tag_ABI_PCS_wchar_t
+ .eabi_attribute 26, 2 @ Tag_ABI_enum_size
+ .eabi_attribute 14, 0 @ Tag_ABI_PCS_R9_use
+ .eabi_attribute 68, 1 @ Tag_Virtualization_use
+ .globl _start
+ .p2align 2
+ .type _start,%function
+_start:
+ .globl func
+ bl func
+ bx lr
+
+// CHECK: BuildAttributes {
+// CHECK-NEXT: FormatVersion: 0x41
+// CHECK-NEXT: Section 1 {
+// CHECK-NEXT: SectionLength: 72
+// CHECK-NEXT: Vendor: aeabi
+// CHECK-NEXT: Tag: Tag_File (0x1)
+// CHECK-NEXT: Size: 62
+// CHECK-NEXT: FileAttributes {
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 67
+// CHECK-NEXT: TagName: conformance
+// CHECK-NEXT: Value: 2.09
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 5
+// CHECK-NEXT: TagName: CPU_name
+// CHECK-NEXT: Value: cortex-a8
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 6
+// CHECK-NEXT: Value: 10
+// CHECK-NEXT: TagName: CPU_arch
+// CHECK-NEXT: Description: ARM v7
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 7
+// CHECK-NEXT: Value: 65
+// CHECK-NEXT: TagName: CPU_arch_profile
+// CHECK-NEXT: Description: Application
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 8
+// CHECK-NEXT: Value: 1
+// CHECK-NEXT: TagName: ARM_ISA_use
+// CHECK-NEXT: Description: Permitted
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 9
+// CHECK-NEXT: Value: 2
+// CHECK-NEXT: TagName: THUMB_ISA_use
+// CHECK-NEXT: Description: Thumb-2
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 10
+// CHECK-NEXT: Value: 3
+// CHECK-NEXT: TagName: FP_arch
+// CHECK-NEXT: Description: VFPv3
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 12
+// CHECK-NEXT: Value: 1
+// CHECK-NEXT: TagName: Advanced_SIMD_arch
+// CHECK-NEXT: Description: NEONv1
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 14
+// CHECK-NEXT: Value: 0
+// CHECK-NEXT: TagName: ABI_PCS_R9_use
+// CHECK-NEXT: Description: v6
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 15
+// CHECK-NEXT: Value: 1
+// CHECK-NEXT: TagName: ABI_PCS_RW_data
+// CHECK-NEXT: Description: PC-relative
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 16
+// CHECK-NEXT: Value: 1
+// CHECK-NEXT: TagName: ABI_PCS_RO_data
+// CHECK-NEXT: Description: PC-relative
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 17
+// CHECK-NEXT: Value: 2
+// CHECK-NEXT: TagName: ABI_PCS_GOT_use
+// CHECK-NEXT: Description: GOT-Indirect
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 18
+// CHECK-NEXT: Value: 4
+// CHECK-NEXT: TagName: ABI_PCS_wchar_t
+// CHECK-NEXT: Description: 4-byte
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 20
+// CHECK-NEXT: Value: 1
+// CHECK-NEXT: TagName: ABI_FP_denormal
+// CHECK-NEXT: Description: IEEE-754
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 21
+// CHECK-NEXT: Value: 1
+// CHECK-NEXT: TagName: ABI_FP_exceptions
+// CHECK-NEXT: Description: IEEE-754
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 23
+// CHECK-NEXT: Value: 3
+// CHECK-NEXT: TagName: ABI_FP_number_model
+// CHECK-NEXT: Description: IEEE-754
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 24
+// CHECK-NEXT: Value: 1
+// CHECK-NEXT: TagName: ABI_align_needed
+// CHECK-NEXT: Description: 8-byte alignment
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 25
+// CHECK-NEXT: Value: 1
+// CHECK-NEXT: TagName: ABI_align_preserved
+// CHECK-NEXT: Description: 8-byte data alignment
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 26
+// CHECK-NEXT: Value: 2
+// CHECK-NEXT: TagName: ABI_enum_size
+// CHECK-NEXT: Description: Int32
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 34
+// CHECK-NEXT: Value: 1
+// CHECK-NEXT: TagName: CPU_unaligned_access
+// CHECK-NEXT: Description: v6-style
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 38
+// CHECK-NEXT: Value: 1
+// CHECK-NEXT: TagName: ABI_FP_16bit_format
+// CHECK-NEXT: Description: IEEE-754
+// CHECK-NEXT: }
+// CHECK-NEXT: Attribute {
+// CHECK-NEXT: Tag: 68
+// CHECK-NEXT: Value: 1
+// CHECK-NEXT: TagName: Virtualization_use
+// CHECK-NEXT: Description: TrustZone
+// CHECK-NEXT: }
Propchange: lld/trunk/test/ELF/arm-attributes.s
------------------------------------------------------------------------------
svn:eol-style = native
Propchange: lld/trunk/test/ELF/arm-attributes.s
------------------------------------------------------------------------------
svn:keywords = Rev Date Author URL Id
More information about the llvm-commits
mailing list