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|
## If a symbol needing a PLT entry also needs a GLOB_DAT relocation, GNU ld's
## x86 port places the PLT entry in .plt.got, relocated by a GLOB_DAT. The
## JUMP_SLOT relocation is unused in this case.
## Test that we synthesize @plt symbols for such PLT entries.
# RUN: yaml2obj --docnum=1 %s -o %t.x86-64
# RUN: llvm-objdump -d %t.x86-64 | FileCheck %s --check-prefix=64
# RUN: yaml2obj --docnum=2 %s -o %t.x86-32
# RUN: llvm-objdump -d %t.x86-32 | FileCheck %s --check-prefix=32
# 64: Disassembly of section .plt:
# 64-EMPTY:
# 64-NEXT: <.plt>:
# 64: <foo1@plt>:
# 64: <foo0@plt>:
# 64: Disassembly of section .plt.got:
# 64-EMPTY:
# 64-NEXT: <combined0@plt>:
# 64: <combined1@plt>:
# 64: <_start>:
# 64-NEXT: movq {{.*}}(%rip), %rax
# 64-NEXT: movq {{.*}}(%rip), %rax
# 64-NEXT: callq {{.*}} <combined0@plt>
# 64-NEXT: callq {{.*}} <combined1@plt>
# 64-NEXT: callq {{.*}} <foo0@plt>
# 64-NEXT: callq {{.*}} <foo1@plt>
# 32: Disassembly of section .plt:
# 32-EMPTY:
# 32-NEXT: <.plt>:
# 32: <foo1@plt>:
# 32: <foo0@plt>:
# 32: Disassembly of section .plt.got:
# 32-EMPTY:
# 32-NEXT: <combined0@plt>:
# 32: <combined1@plt>:
# 32: <_start>:
# 32-NEXT: movl -0x8(%eax), %eax
# 32-NEXT: movl -0x4(%eax), %eax
# 32-NEXT: calll {{.*}} <combined0@plt>
# 32-NEXT: calll {{.*}} <combined1@plt>
# 32-NEXT: calll {{.*}} <foo0@plt>
# 32-NEXT: calll {{.*}} <foo1@plt>
## %t.x86-64 is linked with ld.bfd -pie -z now a.o b.so and
## doesn't have .got.plt.
## %t.x86-32 is linked with ld.bfd -pie -z lazy a.o b.so and
## has .got.plt.
## a.s
## .globl _start; _start:
## mov combined0@gotpcrel(%rip), %rax # movl combined0@GOT(%eax), %eax for x86-32
## mov combined1@gotpcrel(%rip), %rax # movl combined1@GOT(%eax), %eax for x86-32
## call combined0@plt
## call combined1@plt
## call foo0@plt
## call foo1@plt
## b.s
## .globl foo0, foo1, combined0, combined1
## foo0: foo1: combined0: combined1:
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_DYN
Machine: EM_X86_64
Entry: 0x1040
Sections:
- Name: .rela.dyn
Type: SHT_RELA
Flags: [ SHF_ALLOC ]
Address: 0x340
Link: .dynsym
AddressAlign: 0x8
Relocations:
- Offset: 0x2FF0
Symbol: combined0
Type: R_X86_64_GLOB_DAT
- Offset: 0x2FF8
Symbol: combined1
Type: R_X86_64_GLOB_DAT
- Name: .rela.plt
Type: SHT_RELA
Flags: [ SHF_ALLOC, SHF_INFO_LINK ]
Address: 0x370
Link: .dynsym
AddressAlign: 0x8
Info: .got
Relocations:
- Offset: 0x2FE0
Symbol: foo1
Type: R_X86_64_JUMP_SLOT
- Offset: 0x2FE8
Symbol: foo0
Type: R_X86_64_JUMP_SLOT
- Name: .plt
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x1000
AddressAlign: 0x10
EntSize: 0x10
Offset: 0x1000
Content: FF35CA1F0000FF25CC1F00000F1F4000FF25CA1F00006800000000E9E0FFFFFFFF25C21F00006801000000E9D0FFFFFF
- Name: .plt.got
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x1030
AddressAlign: 0x8
EntSize: 0x8
Content: FF25BA1F00006690FF25BA1F00006690
- Name: .text
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x1040
AddressAlign: 0x1
Content: 488B05A91F0000488B05AA1F0000E8DDFFFFFFE8E0FFFFFFE8C3FFFFFFE8AEFFFFFF
- Name: .got
Type: SHT_PROGBITS
Flags: [ SHF_WRITE, SHF_ALLOC ]
Address: 0x2FC8
AddressAlign: 0x8
EntSize: 0x8
Content: '682E000000000000000000000000000000000000000000001610000000000000261000000000000000000000000000000000000000000000'
Symbols:
- Name: _start
Section: .text
Binding: STB_GLOBAL
Value: 0x1040
DynamicSymbols:
- Name: foo1
Binding: STB_GLOBAL
- Name: foo0
Binding: STB_GLOBAL
- Name: combined0
Binding: STB_GLOBAL
- Name: combined1
Binding: STB_GLOBAL
...
--- !ELF
FileHeader:
Class: ELFCLASS32
Data: ELFDATA2LSB
Type: ET_DYN
Machine: EM_386
Entry: 0x1040
Sections:
- Name: .rel.dyn
Type: SHT_REL
Flags: [ SHF_ALLOC ]
Address: 0x218
Link: .dynsym
AddressAlign: 0x4
Relocations:
- Offset: 0x2FEC
Symbol: combined0
Type: R_386_GLOB_DAT
- Offset: 0x2FF0
Symbol: combined1
Type: R_386_GLOB_DAT
- Name: .rel.plt
Type: SHT_REL
Flags: [ SHF_ALLOC, SHF_INFO_LINK ]
Address: 0x228
Link: .dynsym
AddressAlign: 0x4
Info: .got.plt
Relocations:
- Offset: 0x3000
Symbol: foo1
Type: R_386_JUMP_SLOT
- Offset: 0x3004
Symbol: foo0
Type: R_386_JUMP_SLOT
- Name: .plt
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x1000
AddressAlign: 0x10
EntSize: 0x4
Offset: 0x1000
Content: FFB304000000FFA30800000000000000FFA30C0000006800000000E9E0FFFFFFFFA3100000006808000000E9D0FFFFFF
- Name: .plt.got
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x1030
AddressAlign: 0x8
EntSize: 0x8
Content: FFA3F8FFFFFF6690FFA3FCFFFFFF6690
- Name: .text
Type: SHT_PROGBITS
Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
Address: 0x1040
AddressAlign: 0x1
Content: 8B80F8FFFFFF8B80FCFFFFFFE8DFFFFFFFE8E2FFFFFFE8C5FFFFFFE8B0FFFFFF
- Name: .got
Type: SHT_PROGBITS
Flags: [ SHF_WRITE, SHF_ALLOC ]
Address: 0x2FEC
AddressAlign: 0x4
EntSize: 0x4
Content: '0000000000000000'
- Name: .got.plt
Type: SHT_PROGBITS
Flags: [ SHF_WRITE, SHF_ALLOC ]
Address: 0x2FF4
AddressAlign: 0x4
EntSize: 0x4
Content: 442F000000000000000000001610000026100000
Symbols:
- Name: _GLOBAL_OFFSET_TABLE_
Type: STT_OBJECT
Section: .got.plt
Value: 0x2FF4
- Name: _start
Section: .text
Binding: STB_GLOBAL
Value: 0x1040
DynamicSymbols:
- Name: combined0
Binding: STB_GLOBAL
- Name: foo1
Binding: STB_GLOBAL
- Name: foo0
Binding: STB_GLOBAL
- Name: combined1
Binding: STB_GLOBAL
...
|
