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clang-p2996/llvm/test/tools/llvm-objcopy/ELF/binary-paddr.test
Alexey Karyakin c973123fdc [llvm-objcopy] -O binary: do not align physical addresses 
llvm-objcopy should not insert padding before a section if its
physical addresses is not aligned to section's alignment. This
behavior will match GNU objcopy and is important for embedded images
where the physical address is used to store the initial data image.
The loader typically will copy this image using a start symbol
created by the linker. If llvm-objcopy inserts padding before such a
section, the symbol address will not match the location in the image.

This commit refines the change in https://reviews.llvm.org/D128961
which intended to align sections which type changed from NOBITS and
their offset may not be aligned. However, it affected all sections.

Fix https://github.com/llvm/llvm-project/issues/62636

Reviewed By: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D150276
2023-06-20 15:45:33 -07:00

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## The computed LMA of a section in a PT_LOAD equals sh_offset-p_offset+p_paddr.
## The byte offset difference between two sections equals the difference between their LMAs.
## Corollary: if two sections are in the same PT_LOAD, the byte offset
## difference equals the difference between their sh_addr fields.
# RUN: yaml2obj --docnum=1 %s -o %t1
# RUN: llvm-objcopy -O binary %t1 %t1.out
# RUN: od -A x -t x2 %t1.out | FileCheck %s --check-prefix=CHECK1 --ignore-case
# RUN: wc -c %t1.out | FileCheck %s --check-prefix=SIZE1
# CHECK1: 000000 c3c3 c3c3 0000 0000 0000 0000 0000 0000
# CHECK1-NEXT: 000010 0000 0000 0000 0000 0000 0000 0000 0000
# CHECK1-NEXT: *
# CHECK1-NEXT: 001000 3232
# SIZE1: 4098
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_EXEC
Machine: EM_X86_64
Sections:
- Name: .text
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x1000
AddressAlign: 0x1000
Content: "c3c3c3c3"
- Name: .data
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_WRITE ]
Address: 0x2000
AddressAlign: 0x1000
Content: "3232"
ProgramHeaders:
- Type: PT_LOAD
Flags: [ PF_R, PF_W ]
FirstSec: .text
LastSec: .data
## The computed LMA of a section not in a PT_LOAD equals its sh_addr.
# RUN: yaml2obj --docnum=2 %s -o %t2
# RUN: llvm-objcopy -O binary %t2 %t2.out
# RUN: od -A x -t x2 %t2.out | FileCheck %s --check-prefix=CHECK2 --ignore-case
# RUN: wc -c %t2.out | FileCheck %s --check-prefix=SIZE2
## The computed LMA of .data is 0x4000. The minimum LMA of all non-empty sections is 0x1000.
## The content of .data will be written at 0x4000-0x1000 = 0x3000.
# CHECK2: 000000 c3c3 c3c3 0000 0000 0000 0000 0000 0000
# CHECK2-NEXT: 000010 0000 0000 0000 0000 0000 0000 0000 0000
# CHECK2-NEXT: *
# CHECK2-NEXT: 003000 3232
# SIZE2: 12290
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_EXEC
Machine: EM_X86_64
Sections:
- Name: .text
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
## Not in a PT_LOAD. LMA = sh_addr = 0x1000.
Address: 0x1000
AddressAlign: 0x1000
Content: "c3c3c3c3"
- Name: .data
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_WRITE ]
## LMA = sh_offset-p_offset+p_paddr = 0x2000-0x2000+0x4000 = 0x4000.
Address: 0x2000
AddressAlign: 0x1000
Content: "3232"
ProgramHeaders:
- Type: PT_LOAD
Flags: [ PF_R, PF_W ]
VAddr: 0x2000
## p_vaddr is increased from 0x2000 to 0x4000.
PAddr: 0x4000
FirstSec: .data
LastSec: .data
## Check that we use sh_offset instead of sh_addr to decide where to write section contents.
# RUN: yaml2obj --docnum=3 %s -o %t3
# RUN: llvm-objcopy -O binary %t3 %t3.out
# RUN: od -A x -t x2 %t3.out | FileCheck %s --check-prefix=CHECK3 --ignore-case
# RUN: wc -c %t3.out | FileCheck %s --check-prefix=SIZE3
## The minimum LMA of all non-empty sections is 0x1000.
## The content of .data will be written at 0x3000-0x1000 = 0x2000.
# CHECK3: 000000 c3c3 c3c3 0000 0000 0000 0000 0000 0000
# CHECK3-NEXT: 000010 0000 0000 0000 0000 0000 0000 0000 0000
# CHECK3-NEXT: *
# CHECK3-NEXT: 002000 3232
# SIZE3: 8194
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_EXEC
Machine: EM_X86_64
Sections:
- Name: .text
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
## Not in a PT_LOAD. LMA = sh_addr = 0x1000.
Address: 0x1000
AddressAlign: 0x1000
Content: "c3c3c3c3"
- Name: .data
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_WRITE ]
## sh_addr is increased from 0x2000 to 0x3000, but it is ignored.
## LMA = sh_offset-p_offset+p_paddr = 0x2000-0x2000+0x3000 = 0x3000.
Address: 0x3000
AddressAlign: 0x1000
Content: "3232"
ProgramHeaders:
- Type: PT_LOAD
Flags: [ PF_R, PF_W ]
VAddr: 0x3000
FirstSec: .data
LastSec: .data
## The first section (.text) is empty. Test that we skip its LMA until the first
## non-empty section, otherwise we would leave a large number of leading zeroes.
# RUN: yaml2obj --docnum=4 %s -o %t4
# RUN: llvm-objcopy -O binary %t4 %t4.out
# RUN: od -A x -t x2 %t4.out | FileCheck %s --check-prefix=SKIPEMPTY
# SKIPEMPTY: 000000 3232
# SKIPEMPTY-NEXT: 000002
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_EXEC
Machine: EM_X86_64
Sections:
- Name: .text
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x1000
AddressAlign: 0x1000
- Name: gap
Type: Fill
Size: 0x1000
- Name: .data
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_WRITE ]
Content: "3232"
## The last section (.data) is empty. Test that we stop dumping after the last
## non-empty section, otherwise we would leave a large number of trailing zeroes.
# RUN: yaml2obj --docnum=5 %s -o %t5
# RUN: llvm-objcopy -O binary %t5 %t5.out
# RUN: od -A x -t x2 %t5.out | FileCheck %s --check-prefix=SKIPEMPTY
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_EXEC
Machine: EM_X86_64
Sections:
- Name: .text
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x1000
AddressAlign: 0x1000
Content: "3232"
- Name: gap
Type: Fill
Size: 0xffd
- Name: .data
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_WRITE ]
## NOBITS sections should not appear in output.
# RUN: yaml2obj --docnum=6 %s -o %t6
# RUN: llvm-objcopy -O binary %t6 %t6.out
# RUN: od -A x -t x2 %t6.out | FileCheck %s --check-prefix=SKIPNOBITS --ignore-case
# SKIPNOBITS: 000000 c3c3 c3c3
# SKIPNOBITS-NEXT: 000004
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_EXEC
Machine: EM_X86_64
Sections:
- Name: .bss
Type: SHT_NOBITS
Flags: [ SHF_ALLOC ]
Address: 0x1000
AddressAlign: 0x1000
Size: 0x123
- Name: gap
Type: Fill
Size: 0xffd
- Name: .text
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x4000
AddressAlign: 0x1000
Content: "c3c3c3c3"
## If .bss is converted to non-SHT_NOBITS, align its new offset. This may affect
## the output size.
# RUN: yaml2obj --docnum=7 %s -o %t7
# RUN: llvm-objcopy -O binary --set-section-flags .bss=alloc,contents %t7 %t7.out
# RUN: od -A x -t x2 %t7.out | FileCheck %s --check-prefix=FILLNOBITS --ignore-case
# FILLNOBITS: 000000 c3c3 0000 0000 0000 0000 0000 0000 0000
# FILLNOBITS-NEXT: 000010 0000 00
# FILLNOBITS-NEXT: 000013
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_EXEC
Machine: EM_X86_64
Sections:
- Name: .text
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x1000
AddressAlign: 0x1000
Content: "c3c3"
- Name: .bss
Type: SHT_NOBITS
Flags: [ SHF_ALLOC ]
## sh_offset is not aligned.
ShOffset: 0x1002
Size: 0x3
AddressAlign: 0x10
ProgramHeaders:
- Type: PT_LOAD
Flags: [ PF_R, PF_W, PF_X ]
Offset: 0x1000
VAddr: 0x1000
PAddr: 0x1000
FileSize: 0x2
MemSize: 0x13
Align: 0x1000
## Test that sections do not move relative to their physical addresses if
## the physical address is not aligned. This behavior matches GNU objcopy
## and is important for embedded images where the physical address is
## used to store the initial data image. Without converting the type of a
## NOBITS section, don't align the offset. This matches GNU objcopy when
## the physical address of a section is not aligned.
# RUN: yaml2obj --docnum=8 %s -o %t8
# RUN: llvm-objcopy -O binary --only-section=.text --only-section=.data %t8 %t8.out
# RUN: od -A x -t x1 %t8.out | FileCheck %s --check-prefix=PHYSUNALIGNED --ignore-case
# PHYSUNALIGNED: 000000 11 22 33 44 55 66 77 88 99 aa bb cc dd ee ff 00
# PHYSUNALIGNED-NEXT: 000010 11 22 33 44 bd ac cd ab
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_EXEC
Machine: EM_X86_64
ProgramHeaders:
- Type: PT_LOAD
Flags: [ PF_X, PF_R ]
FirstSec: .text
LastSec: .text
VAddr: 0x200000
PAddr: 0x200000
Align: 0x1000
- Type: PT_LOAD
Flags: [ PF_W, PF_R ]
FirstSec: .data
LastSec: .data
VAddr: 0x400000
PAddr: 0x200014
## PAddr is not aligned by sh_addralign(.data)
Align: 0x1000
Sections:
- Name: .text
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x200000
AddressAlign: 0x1
Offset: 0x1000
Content: 112233445566778899aabbccddeeff0011223344
- Name: .data
Type: SHT_PROGBITS
Flags: [ SHF_WRITE, SHF_ALLOC ]
Address: 0x400000
AddressAlign: 0x8
Offset: 0x2000
Content: BDACCDAB
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