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Differential D73105

[llvm-readobj] - Add a test for --hash-table option.
ClosedPublic

Authored by grimar on Jan 21 2020, 7:01 AM.

Details

Reviewers
jhenderson
MaskRay
• espindola
Commits
rGa33427447df0: [llvm-readobj] - Add a test for --hash-table option.
Summary

We had no test for --hash-table in tools/llvm-readobj.

The one we had was in test/Object and checked that
it is possible to dump the hash table even when an object
doesn't have a section header table.

In this patch I created a test, moved and merged the existent one.
During moving I converted it to be YAML based to stop using the
precompiled binary.

Diff Detail

Event Timeline

grimar created this revision.Jan 21 2020, 7:01 AM
Herald added a reviewer: • espindola. · View Herald TranscriptJan 21 2020, 7:01 AM
Herald added a project: Restricted Project. · View Herald Transcript
Herald added subscribers: rupprecht, emaste. · View Herald Transcript
jhenderson added inline comments.Jan 23 2020, 7:59 AM
llvm/test/tools/llvm-readobj/ELF/hash-table.test
92–93

Whilst I see what you're doing here, I think the test would be less confusing if you used llvm-objcopy --strip-sections to remove the section header table. You could then use the same input and checks as the first test case(s).

grimar marked 2 inline comments as done.Jan 24 2020, 2:46 AM
grimar added inline comments.
llvm/test/tools/llvm-readobj/ELF/hash-table.test
92–93

It will not work, because I need a PT_DYNAMIC segment to find .dynamic here. YAMLs above does not have it.
I think we do not want to add it there, as they show we can dump hash table using headers table only.

jhenderson added inline comments.Jan 24 2020, 4:02 AM
llvm/test/tools/llvm-readobj/ELF/hash-table.test
73

Perhaps add a comment saying that we simulate no section header table by overriding the ELF header properties.

92–93

Okay, makes sense.

grimar updated this revision to Diff 240161.Jan 24 2020, 4:18 AM
grimar marked 4 inline comments as done.
  • Addressed review comment.
llvm/test/tools/llvm-readobj/ELF/hash-table.test
73

I've inlined it to the YAML description below.

jhenderson accepted this revision.Jan 24 2020, 4:28 AM

LGTM.

llvm/test/tools/llvm-readobj/ELF/hash-table.test
93–94

Perhaps change 0x0 -> 0 (or vice versa) for consistency/readability. Not a big issue though, if you prefer as is.

This revision is now accepted and ready to land.Jan 24 2020, 4:28 AM
Closed by commit rGa33427447df0: [llvm-readobj] - Add a test for --hash-table option. (authored by grimar). · Explain WhyJan 27 2020, 1:33 AM
This revision was automatically updated to reflect the committed changes.
grimar marked an inline comment as done.

Revision Contents

PathSize
llvm/
test/
Object/
Inputs/
tools/
llvm-readobj/
ELF/
117 lines

Diff 240161

llvm/test/Object/Inputs/no-section-table.so

  • This binary file was deleted.

llvm/test/Object/no-section-table.test

  • This file was deleted.
RUN: llvm-readobj %p/Inputs/no-section-table.so -hash-table -dynamic-table \
RUN: | FileCheck %s
CHECK: DynamicSection [ (24 entries)
CHECK: Tag Type Name/Value
CHECK: 0x0000000000000001 NEEDED Shared library: [libc.so.6]
CHECK: 0x000000000000000C INIT 0x4B8
CHECK: 0x000000000000000D FINI 0x618
CHECK: 0x0000000000000019 INIT_ARRAY 0x2006C0
CHECK: 0x000000000000001B INIT_ARRAYSZ 8 (bytes)
CHECK: 0x000000000000001A FINI_ARRAY 0x2006C8
CHECK: 0x000000000000001C FINI_ARRAYSZ 8 (bytes)
CHECK: 0x0000000000000004 HASH 0x158
CHECK: 0x0000000000000005 STRTAB 0x2D8
CHECK: 0x0000000000000006 SYMTAB 0x1A0
CHECK: 0x000000000000000A STRSZ 179 (bytes)
CHECK: 0x000000000000000B SYMENT 24 (bytes)
CHECK: 0x0000000000000003 PLTGOT 0x2008C0
CHECK: 0x0000000000000002 PLTRELSZ 48 (bytes)
CHECK: 0x0000000000000014 PLTREL RELA
CHECK: 0x0000000000000017 JMPREL 0x488
CHECK: 0x0000000000000007 RELA 0x3C8
CHECK: 0x0000000000000008 RELASZ 192 (bytes)
CHECK: 0x0000000000000009 RELAENT 24 (bytes)
CHECK: 0x000000006FFFFFFE VERNEED 0x3A8
CHECK: 0x000000006FFFFFFF VERNEEDNUM 1
CHECK: 0x000000006FFFFFF0 VERSYM 0x38C
CHECK: 0x000000006FFFFFF9 RELACOUNT 3
CHECK: 0x0000000000000000 NULL 0x0
CHECK: ]
CHECK: HashTable {
CHECK: Num Buckets: 3
CHECK: Num Chains: 13
CHECK: Buckets: [12, 10, 11]
CHECK: Chains: [0, 0, 0, 0, 2, 3, 4, 0, 7, 5, 6, 8, 9]
CHECK: }

llvm/test/tools/llvm-readobj/ELF/hash-table.test

  • This file was added.
## Check how the SHT_HASH section is dumped with --hash-table.
# RUN: yaml2obj --docnum=1 %s -o %t.x64
# RUN: yaml2obj --docnum=2 %s -o %t.x32
# RUN: llvm-readobj --hash-table %t.x64 | FileCheck %s --check-prefix=HASH
# RUN: llvm-readelf --hash-table %t.x64 | FileCheck %s --check-prefix=HASH
# RUN: llvm-readobj --hash-table %t.x32 | FileCheck %s --check-prefix=HASH
# RUN: llvm-readelf --hash-table %t.x32 | FileCheck %s --check-prefix=HASH
# HASH: HashTable {
# HASH-NEXT: Num Buckets: 2
# HASH-NEXT: Num Chains: 3
# HASH-NEXT: Buckets: [1, 2]
# HASH-NEXT: Chains: [3, 4, 5]
# HASH-NEXT: }
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_DYN
Machine: EM_X86_64
Sections:
- Name: .hash
Type: SHT_HASH
Flags: [ SHF_ALLOC ]
Bucket: [ 1, 2 ]
Chain: [ 3, 4, 5 ]
- Name: .dynamic
Type: SHT_DYNAMIC
Flags: [ SHF_ALLOC ]
Entries:
- Tag: DT_HASH
Value: 0x0
- Tag: DT_NULL
Value: 0x0
ProgramHeaders:
- Type: PT_LOAD
Sections:
- Section: .hash
- Section: .dynamic
--- !ELF
FileHeader:
Class: ELFCLASS32
Data: ELFDATA2LSB
Type: ET_DYN
Machine: EM_386
Sections:
- Name: .hash
Type: SHT_HASH
Flags: [ SHF_ALLOC ]
Bucket: [ 1, 2 ]
Chain: [ 3, 4, 5 ]
- Name: .dynamic
Type: SHT_DYNAMIC
Flags: [ SHF_ALLOC ]
Entries:
- Tag: DT_HASH
Value: 0x0
- Tag: DT_NULL
Value: 0x0
ProgramHeaders:
- Type: PT_LOAD
Sections:
- Section: .hash
- Section: .dynamic
## Check we can dump the SHT_HASH section even when an object
## does not have the section header table.
jhendersonUnsubmitted
Done
ReplyInline Actions

Perhaps add a comment saying that we simulate no section header table by overriding the ELF header properties.

jhenderson: Perhaps add a comment saying that we simulate no section header table by overriding the ELF…
grimarAuthorUnsubmitted
Done
ReplyInline Actions

I've inlined it to the YAML description below.

grimar: I've inlined it to the YAML description below.
# RUN: yaml2obj --docnum=3 %s -o %t.noshdr
# RUN: llvm-readobj --hash-table %t.noshdr | FileCheck %s --check-prefix=NOSHDR
# RUN: llvm-readelf --hash-table %t.noshdr | FileCheck %s --check-prefix=NOSHDR
# NOSHDR: HashTable {
# NOSHDR-NEXT: Num Buckets: 1
# NOSHDR-NEXT: Num Chains: 1
# NOSHDR-NEXT: Buckets: [0]
# NOSHDR-NEXT: Chains: [1]
# NOSHDR-NEXT: }
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_DYN
Machine: EM_X86_64
## We simulate no section header table by
## overriding the ELF header properties.
SHOff: 0x0
jhendersonUnsubmitted
Done
ReplyInline Actions

Whilst I see what you're doing here, I think the test would be less confusing if you used llvm-objcopy --strip-sections to remove the section header table. You could then use the same input and checks as the first test case(s).

jhenderson: Whilst I see what you're doing here, I think the test would be less confusing if you used llvm…
grimarAuthorUnsubmitted
Done
ReplyInline Actions

It will not work, because I need a PT_DYNAMIC segment to find .dynamic here. YAMLs above does not have it.
I think we do not want to add it there, as they show we can dump hash table using headers table only.

grimar: It will not work, because I need a `PT_DYNAMIC` segment to find `.dynamic` here. YAMLs above…
jhendersonUnsubmitted
Done
ReplyInline Actions

Okay, makes sense.

jhenderson: Okay, makes sense.
SHNum: 0
jhendersonUnsubmitted
Done
ReplyInline Actions

Perhaps change 0x0 -> 0 (or vice versa) for consistency/readability. Not a big issue though, if you prefer as is.

jhenderson: Perhaps change 0x0 -> 0 (or vice versa) for consistency/readability. Not a big issue though, if…
Sections:
- Name: .hash
Type: SHT_HASH
Flags: [ SHF_ALLOC ]
Bucket: [ 0 ]
Chain: [ 1 ]
- Name: .dynamic
Type: SHT_DYNAMIC
Flags: [ SHF_ALLOC ]
Entries:
- Tag: DT_HASH
Value: 0x0
- Tag: DT_NULL
Value: 0x0
ProgramHeaders:
- Type: PT_LOAD
Sections:
- Section: .hash
- Section: .dynamic
- Type: PT_DYNAMIC
VAddr: 0x1010
Sections:
- Section: .dynamic