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# RUN: yaml2obj --docnum=1 %s -o %t1
# RUN: llvm-objcopy --only-keep-debug %t1 %t1.dbg
# RUN: llvm-readelf -S -l -x .note1 -x .note2 -x .debug_abbrev -x .debug_frame -x .debug_info %t1.dbg | FileCheck %s
## Check that SHT_NOTE and .debug* are kept, but others are changed to SHT_NOBITS.
## SHT_NOBITS sections do not occupy space in the output.
# CHECK: [Nr] Name Type Address Off Size ES Flg Lk Inf Al
# CHECK: [ 1] .note1 NOTE 0000000000000400 000400 000001 00 A 0 0 1024
# CHECK-NEXT: [ 2] .note2 NOTE 0000000000000401 000401 000001 00 A 0 0 0
# CHECK-NEXT: [ 3] .text NOBITS 0000000000000402 000402 000001 00 AX 0 0 0
# CHECK-NEXT: [ 4] .tdata NOBITS 0000000000001480 000480 000007 00 WAT 0 0 128
# CHECK-NEXT: [ 5] .tbss NOBITS 0000000000001487 000480 000005 00 WAT 0 0 0
# CHECK-NEXT: [ 6] .bss NOBITS 00000000000014a0 000480 00003f 00 WA 0 0 32
## objcopy sets sh_offset to 0x402. We don't do this to keep sh_offset non-decreasing.
# CHECK-NEXT: [ 7] .debug_abbrev PROGBITS 0000000000000000 000480 000001 00 0 0 0
# CHECK-NEXT: [ 8] .debug_frame PROGBITS 0000000000000000 000488 000001 00 0 0 8
# CHECK-NEXT: [ 9] .debug_info PROGBITS 0000000000000000 000489 000001 00 0 0 0
# CHECK-NEXT: [10] .strtab STRTAB 0000000000000000 00048a 000001 00 0 0 1
# CHECK-NEXT: [11] .shstrtab STRTAB 0000000000000000 00048b 000060 00 0 0 1
# CHECK: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align
# CHECK-NEXT: LOAD 0x000000 0x0000000000000000 0x0000000000000000 0x000402 0x000403 R E 0x1000
# CHECK-NEXT: LOAD 0x000480 0x0000000000001480 0x0000000000000000 0x000000 0x00005f RW 0x1000
# CHECK-NEXT: TLS 0x000480 0x0000000000001480 0x0000000000000000 0x000000 0x00000c RW 0x80
# CHECK-NEXT: NOTE 0x000400 0x0000000000000400 0x0000000000000000 0x000002 0x000002 0x400
## Contents of SHT_NOTE and .debug* are kept.
# CHECK: Hex dump of section '.note1':
# CHECK-NEXT: 0x00000400 01
# CHECK: Hex dump of section '.note2':
# CHECK-NEXT: 0x00000401 02
# CHECK: Hex dump of section '.debug_abbrev':
# CHECK-NEXT: 0x00000000 03
# CHECK: Hex dump of section '.debug_frame':
# CHECK-NEXT: 0x00000000 04
# CHECK: Hex dump of section '.debug_info':
# CHECK-NEXT: 0x00000000 05
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_DYN
Machine: EM_X86_64
Sections:
- Name: .note1
Type: SHT_NOTE
Flags: [ SHF_ALLOC ]
Address: 0x400
AddressAlign: 0x400
Content: 01
- Name: .note2
Type: SHT_NOTE
Flags: [ SHF_ALLOC ]
Address: 0x401
Content: 02
- Name: .text
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x402
Content: c3
- Name: .tdata
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_WRITE, SHF_TLS ]
Address: 0x1480 # Ensure Address=0x1000+Offset
AddressAlign: 0x80
# An arbitrary non-zero Size tests that .tdata does not occupy space
# and we can rewrite p_filesz of PT_TLS.
Size: 7
- Name: .tbss
Type: SHT_NOBITS
Flags: [ SHF_ALLOC, SHF_WRITE, SHF_TLS ]
Address: 0x1487 # Ensure Address=0x1000+Offset
Size: 5
- Name: .bss
Type: SHT_NOBITS
Flags: [ SHF_ALLOC, SHF_WRITE ]
Address: 0x14a0 # Ensure Address=0x1000+Offset
AddressAlign: 0x20
# An arbitrary non-zero Size tests that .bss does not occupy space.
Size: 63
- Name: .debug_abbrev
Type: SHT_PROGBITS
Content: 03
- Name: .debug_frame
Type: SHT_PROGBITS
# AddressAlign tests the file offset assignment leaves a gap.
AddressAlign: 0x8
Content: 04
- Name: .debug_info
Type: SHT_PROGBITS
Content: 05
ProgramHeaders:
- Type: PT_LOAD
Flags: [ PF_R, PF_X ]
Offset: 0
Align: 0x1000
Sections:
- Section: .note1
- Section: .note2
- Section: .text
- Type: PT_LOAD
Flags: [ PF_R, PF_W ]
VAddr: 0x1480 # Ensure Offset=VAddr (mod Align) if Offset changes
Align: 0x1000
Sections:
- Section: .tdata
- Section: .bss
- Type: PT_TLS
Flags: [ PF_R, PF_W ]
VAddr: 0x1480 # Ensure Offset=VAddr (mod Align) if Offset changes
Sections:
- Section: .tdata
- Section: .tbss
- Type: PT_NOTE
VAddr: 0x400
Sections:
- Section: .note1
- Section: .note2
...
# RUN: yaml2obj --docnum=2 %s -o %t2
# RUN: llvm-objcopy --only-keep-debug %t2 %t2.dbg
# RUN: llvm-readelf -S -l %t2.dbg | FileCheck --check-prefix=CHECK2 %s
## Only the tail of a segment can be trimmed. .text still occupies space because
## it is followed by .note which is not SHT_NOBITS.
# CHECK2: [Nr] Name Type Address Off Size ES Flg Lk Inf Al
# CHECK2: [ 1] .text NOBITS 0000000000000200 000200 000001 00 AX 0 0 512
# CHECK2-NEXT: [ 2] .note NOTE 0000000000000201 000201 000001 00 A 0 0 0
# CHECK2-NEXT: [ 3] .debug_info PROGBITS 0000000000000000 000220 000001 00 0 0 32
# CHECK2-NEXT: [ 4] .strtab STRTAB 0000000000000000 000221 000001 00 0 0 1
# CHECK2-NEXT: [ 5] .shstrtab STRTAB 0000000000000000 000222 00002b 00 0 0 1
## Check that p_offset or p_filesz of empty segments or PT_PHDR are not modified.
# CHECK2: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align
# CHECK2-NEXT: PHDR 0x000040 0x0000000000000040 0x0000000000000000 0x0000a8 0x0000a8 R 0x8
# CHECK2-NEXT: LOAD 0x000000 0x0000000000000000 0x0000000000000000 0x000202 0x000202 R E 0x1000
# CHECK2-NEXT: LOAD 0x000202 0x0000000000000202 0x0000000000000000 0x00000e 0x00000e RW 0x1
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_DYN
Machine: EM_X86_64
Sections:
- Name: .text
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x200
AddressAlign: 0x200
Content: c3
- Name: .note
Type: SHT_NOTE
Flags: [ SHF_ALLOC ]
Address: 0x201
Content: 01
- Name: .debug_info
Type: SHT_PROGBITS
AddressAlign: 0x20
Content: 02
ProgramHeaders:
- Type: PT_PHDR
Flags: [ PF_R ]
Offset: 0x40
VAddr: 0x40
# 3 * sizeof(Elf64_Phdr) = 0xa8
FileSize: 0xa8
MemSize: 0xa8
Align: 8
- Type: PT_LOAD
Flags: [ PF_R, PF_X ]
Offset: 0
Align: 4096
Sections:
- Section: .text
- Section: .note
- Type: PT_LOAD
Flags: [ PF_R, PF_W ]
Offset: 0x202
VAddr: 0x202
FileSize: 14
MemSize: 14
...
## If .symtab or .strtab has the SHF_ALLOC flag, it will be changed to SHT_NOBITS.
# RUN: yaml2obj --docnum=3 %s -o %t3
# RUN: llvm-objcopy --only-keep-debug %t3 %t3.dbg
# RUN: llvm-readelf -S -l %t3.dbg | FileCheck --check-prefix=CHECK3 %s
# CHECK3: [Nr] Name Type Address Off Size ES Flg Lk Inf Al
# CHECK3: [ 1] .dynsym NOBITS 0000000000000000 000040 000018 18 A 2 1 1024
# CHECK3-NEXT: [ 2] .dynstr NOBITS 0000000000000000 000040 000001 00 A 0 0 0
# CHECK3-NEXT: [ 3] .symtab NOBITS 0000000000000000 000040 000018 18 A 4 1 0
# CHECK3-NEXT: [ 4] .strtab NOBITS 0000000000000000 000040 000001 00 A 0 0 0
# CHECK3-NEXT: [ 5] .shstrtab STRTAB 0000000000000000 000040 00002b 00 0 0 1
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_DYN
Machine: EM_X86_64
Sections:
- Name: .dynsym
Type: SHT_DYNSYM
Flags: [ SHF_ALLOC ]
Link: .dynstr
AddressAlign: 0x400
- Name: .dynstr
Type: SHT_STRTAB
Flags: [ SHF_ALLOC ]
- Name: .symtab
Type: SHT_STRTAB
Flags: [ SHF_ALLOC ]
Link: .strtab
- Name: .strtab
Type: SHT_STRTAB
Flags: [ SHF_ALLOC ]
DynamicSymbols: []
Symbols: []
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