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Differential D41744

Retpoline
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Authored by ruiu on Jan 4 2018, 4:26 PM.
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ruiu created this revision.Jan 4 2018, 4:26 PM
Herald added a subscriber: emaste. · View Herald TranscriptJan 4 2018, 4:26 PM

Revision Contents

PathSize
lld/
ELF/
Arch/
14 lines
31 lines
test/
ELF/
17 lines
17 lines
69 lines

Diff 128676

lld/ELF/Arch/X86.cpp

Show First 20 Lines • Show All 429 Lines • ▼ Show 20 Lines
void RetpolinePic::writePltHeader(uint8_t *Buf) const { void RetpolinePic::writePltHeader(uint8_t *Buf) const {
const uint8_t Insn[] = { const uint8_t Insn[] = {
0x50, // pushl %eax 0x50, // pushl %eax
0x8b, 0x83, 0, 0, 0, 0, // mov GOTPLT+8(%ebx), %eax 0x8b, 0x83, 0, 0, 0, 0, // mov GOTPLT+8(%ebx), %eax
0xe8, 0x04, 0x00, 0x00, 0x00, // call next 0xe8, 0x04, 0x00, 0x00, 0x00, // call next
0xf3, 0x90, // loop: pause 0xf3, 0x90, // loop: pause
0xeb, 0xfc, // jmp loop; .align 16 0xeb, 0xfc, // jmp loop; .align 16
0x83, 0xc4, 0x04, // next: add $4, %esp 0x89, 0x0c, 0x24, // next: mov %ecx, (%esp)
0x87, 0x04, 0x24, // xchg %eax, (%esp) 0x8b, 0x4c, 0x24, 0x04, // mov 0x4(%esp), %ecx
0x89, 0x44, 0x24, 0x04, // mov %eax ,0x4(%esp)
0x89, 0xc8, // mov %ecx, %eax
0x59, // pop %ecx
0xc3, // ret 0xc3, // ret
}; };
memcpy(Buf, Insn, sizeof(Insn)); memcpy(Buf, Insn, sizeof(Insn));
uint32_t Ebx = InX::Got->getVA() + InX::Got->getSize(); uint32_t Ebx = InX::Got->getVA() + InX::Got->getSize();
uint32_t GotPlt = InX::GotPlt->getVA() - Ebx; uint32_t GotPlt = InX::GotPlt->getVA() - Ebx;
write32le(Buf + 3, GotPlt + 8); write32le(Buf + 3, GotPlt + 8);
} }
Show All 34 Lines
void RetpolineNoPic::writePltHeader(uint8_t *Buf) const { void RetpolineNoPic::writePltHeader(uint8_t *Buf) const {
const uint8_t PltData[] = { const uint8_t PltData[] = {
0x50, // pushl %eax 0x50, // pushl %eax
0xa1, 0, 0, 0, 0, // mov GOTPLT+8, %eax 0xa1, 0, 0, 0, 0, // mov GOTPLT+8, %eax
0xe8, 0x05, 0x00, 0x00, 0x00, // call next 0xe8, 0x05, 0x00, 0x00, 0x00, // call next
0xf3, 0x90, // loop: pause 0xf3, 0x90, // loop: pause
0xeb, 0xfc, // jmp loop 0xeb, 0xfc, // jmp loop
0x90, // nop; .align 16 0x90, // nop; .align 16
0x83, 0xc4, 0x04, // next: add $4, %esp 0x89, 0x0c, 0x24, // next: mov %ecx, (%esp)
0x87, 0x04, 0x24, // xchg %eax, (%esp) 0x8b, 0x4c, 0x24, 0x04, // mov 0x4(%esp), %ecx
0x89, 0x44, 0x24, 0x04, // mov %eax ,0x4(%esp)
0x89, 0xc8, // mov %ecx, %eax
0x59, // pop %ecx
0xc3, // ret 0xc3, // ret
}; };
memcpy(Buf, PltData, sizeof(PltData)); memcpy(Buf, PltData, sizeof(PltData));
uint32_t GotPlt = InX::GotPlt->getVA(); uint32_t GotPlt = InX::GotPlt->getVA();
write32le(Buf + 2, GotPlt + 8); write32le(Buf + 2, GotPlt + 8);
} }
Show All 37 Lines

lld/ELF/Arch/X86_64.cpp

Show First 20 Lines • Show All 475 Lines • ▼ Show 20 Linespublic:
void writePltHeader(uint8_t *Buf) const override; void writePltHeader(uint8_t *Buf) const override;
void writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, uint64_t PltEntryAddr, void writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, uint64_t PltEntryAddr,
int32_t Index, unsigned RelOff) const override; int32_t Index, unsigned RelOff) const override;
}; };
} // namespace } // namespace
template <class ELFT> Retpoline<ELFT>::Retpoline() { template <class ELFT> Retpoline<ELFT>::Retpoline() {
TargetInfo::PltEntrySize = 32; TargetInfo::PltEntrySize = 32;
TargetInfo::PltHeaderSize = 48; TargetInfo::PltHeaderSize = 32;
} }
template <class ELFT> template <class ELFT>
void Retpoline<ELFT>::writeGotPlt(uint8_t *Buf, const Symbol &S) const { void Retpoline<ELFT>::writeGotPlt(uint8_t *Buf, const Symbol &S) const {
write32le(Buf, S.getPltVA() + 21); write32le(Buf, S.getPltVA() + 16);
} }
template <class ELFT> void Retpoline<ELFT>::writePltHeader(uint8_t *Buf) const { template <class ELFT> void Retpoline<ELFT>::writePltHeader(uint8_t *Buf) const {
const uint8_t Insn[] = { const uint8_t Insn[] = {
0xff, 0x35, 0, 0, 0, 0, // pushq GOTPLT+8(%rip)
0x4c, 0x8b, 0x1d, 0, 0, 0, 0, // mov GOTPLT+16(%rip), %r11 0x4c, 0x8b, 0x1d, 0, 0, 0, 0, // mov GOTPLT+16(%rip), %r11
0xe8, 0x0e, 0x00, 0x00, 0x00, // callq next 0xe8, 0x04, 0x00, 0x00, 0x00, // callq next
0xf3, 0x90, // loop: pause 0xf3, 0x90, // loop: pause
0xeb, 0xfc, // jmp loop 0xeb, 0xfc, // jmp loop; .align 16
0x0f, 0x1f, 0x44, 0x00, 0x00, // nop
0x0f, 0x1f, 0x44, 0x00, 0x00, // nop; .align 16
0x4c, 0x89, 0x1c, 0x24, // next: mov %r11, (%rsp) 0x4c, 0x89, 0x1c, 0x24, // next: mov %r11, (%rsp)
0xc3, // ret 0xc3, // ret
}; };
memcpy(Buf, Insn, sizeof(Insn)); memcpy(Buf, Insn, sizeof(Insn));
uint64_t GotPlt = InX::GotPlt->getVA(); uint64_t GotPlt = InX::GotPlt->getVA();
uint64_t Plt = InX::Plt->getVA(); uint64_t Plt = InX::Plt->getVA();
write32le(Buf + 2, GotPlt - Plt + 2); // GOTPLT+8 write32le(Buf + 3, GotPlt - Plt + 16 - 7);
write32le(Buf + 9, GotPlt - Plt + 3); // GOTPLT+16
} }
template <class ELFT> template <class ELFT>
void Retpoline<ELFT>::writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr, void Retpoline<ELFT>::writePlt(uint8_t *Buf, uint64_t GotPltEntryAddr,
uint64_t PltEntryAddr, int32_t Index, uint64_t PltEntryAddr, int32_t Index,
unsigned RelOff) const { unsigned RelOff) const {
const uint8_t Insn[] = { const uint8_t Insn[] = {
0x4c, 0x8b, 0x1d, 0, 0, 0, 0, // mov foo@GOTPLT(%rip), %r11 0x4c, 0x8b, 0x1d, 0, 0, 0, 0, // mov foo@GOTPLT(%rip), %r11
0xe8, 0x04, 0x00, 0x00, 0x00, // callq next 0xe8, 0, 0, 0, 0, // callq plt+16
0xf3, 0x90, // loop: pause 0xf3, 0x90, // loop: pause
0xeb, 0xfc, // jmp loop; .align 16 0xeb, 0xfc, // jmp loop; .align 16
0x4c, 0x89, 0x1c, 0x24, // next: mov %r11, (%rsp)
0xc3, // ret
0x68, 0, 0, 0, 0, // pushq <relocation index> 0x68, 0, 0, 0, 0, // pushq <relocation index>
0xff, 0x35, 0, 0, 0, 0, // pushq GOTPLT+8(%rip)
0xe9, 0, 0, 0, 0, // jmpq plt[0] 0xe9, 0, 0, 0, 0, // jmpq plt[0]
0xcc, // int3
}; };
memcpy(Buf, Insn, sizeof(Insn)); memcpy(Buf, Insn, sizeof(Insn));
uint64_t GotPlt = InX::GotPlt->getVA();
uint64_t Plt = InX::Plt->getVA();
uint64_t Off = TargetInfo::PltHeaderSize + TargetInfo::PltEntrySize * Index;
write32le(Buf + 3, GotPltEntryAddr - PltEntryAddr - 7); write32le(Buf + 3, GotPltEntryAddr - PltEntryAddr - 7);
write32le(Buf + 22, Index); write32le(Buf + 8, -Off - 12 + 16);
write32le(Buf + 27, write32le(Buf + 17, Index);
-Index * TargetInfo::PltEntrySize - TargetInfo::PltHeaderSize - 31); write32le(Buf + 23, GotPlt - Plt - Off + 8 - 27);
write32le(Buf + 28, -Off - 32);
} }
template <class ELFT> template <class ELFT>
void RetpolineZNow<ELFT>::writePltHeader(uint8_t *Buf) const { void RetpolineZNow<ELFT>::writePltHeader(uint8_t *Buf) const {
const uint8_t Insn[] = { const uint8_t Insn[] = {
0x4c, 0x89, 0x1c, 0x24, // mov %r11, (%rsp) 0x4c, 0x89, 0x1c, 0x24, // mov %r11, (%rsp)
0xc3, // ret 0xc3, // ret
}; };
Show All 36 Lines

lld/test/ELF/i386-retpoline-nopic.s

// REQUIRES: x86 // REQUIRES: x86
// RUN: llvm-mc -filetype=obj -triple=i386-unknown-linux %s -o %t1.o // RUN: llvm-mc -filetype=obj -triple=i386-unknown-linux %s -o %t1.o
// RUN: llvm-mc -filetype=obj -triple=i386-unknown-linux %p/Inputs/shared.s -o %t2.o // RUN: llvm-mc -filetype=obj -triple=i386-unknown-linux %p/Inputs/shared.s -o %t2.o
// RUN: ld.lld -shared %t2.o -o %t2.so // RUN: ld.lld -shared %t2.o -o %t2.so
// RUN: ld.lld %t1.o %t2.so -o %t.exe -z retpolineplt // RUN: ld.lld %t1.o %t2.so -o %t.exe -z retpolineplt
// RUN: llvm-objdump -d %t.exe | FileCheck %s // RUN: llvm-objdump -d %t.exe | FileCheck %s
// CHECK: 11010: 50 pushl %eax // CHECK: 11010: 50 pushl %eax
// CHECK-NEXT: 11011: a1 08 20 01 00 movl 73736, %eax // CHECK-NEXT: 11011: a1 08 20 01 00 movl 73736, %eax
// CHECK-NEXT: 11016: e8 05 00 00 00 calll 5 <.plt+0x10> // CHECK-NEXT: 11016: e8 05 00 00 00 calll 5 <.plt+0x10>
// CHECK-NEXT: 1101b: f3 90 pause // CHECK-NEXT: 1101b: f3 90 pause
// CHECK-NEXT: 1101d: eb fc jmp -4 <.plt+0xb> // CHECK-NEXT: 1101d: eb fc jmp -4 <.plt+0xb>
// CHECK-NEXT: 1101f: 90 nop // CHECK-NEXT: 1101f: 90 nop
// CHECK-NEXT: 11020: 83 c4 04 addl $4, %esp // CHECK-NEXT: 11020: 89 0c 24 movl %ecx, (%esp)
// CHECK-NEXT: 11023: 87 04 24 xchgl %eax, (%esp) // CHECK-NEXT: 11023: 8b 4c 24 04 movl 4(%esp), %ecx
// CHECK-NEXT: 11026: c3 retl // CHECK-NEXT: 11027: 89 44 24 04 movl %eax, 4(%esp)
// CHECK-NEXT: 11027: cc int3 // CHECK-NEXT: 1102b: 89 c8 movl %ecx, %eax
// CHECK-NEXT: 11028: cc int3 // CHECK-NEXT: 1102d: 59 popl %ecx
// CHECK-NEXT: 11029: cc int3 // CHECK-NEXT: 1102e: c3 retl
// CHECK-NEXT: 1102a: cc int3
// CHECK-NEXT: 1102b: cc int3
// CHECK-NEXT: 1102c: cc int3
// CHECK-NEXT: 1102d: cc int3
// CHECK-NEXT: 1102e: cc int3
// CHECK-NEXT: 1102f: cc int3 // CHECK-NEXT: 1102f: cc int3
// CHECK-NEXT: 11030: 50 pushl %eax // CHECK-NEXT: 11030: 50 pushl %eax
// CHECK-NEXT: 11031: a1 0c 20 01 00 movl 73740, %eax // CHECK-NEXT: 11031: a1 0c 20 01 00 movl 73740, %eax
// CHECK-NEXT: 11036: e8 e5 ff ff ff calll -27 <.plt+0x10> // CHECK-NEXT: 11036: e8 e5 ff ff ff calll -27 <.plt+0x10>
// CHECK-NEXT: 1103b: f3 90 pause // CHECK-NEXT: 1103b: f3 90 pause
// CHECK-NEXT: 1103d: eb fc jmp -4 <.plt+0x2b> // CHECK-NEXT: 1103d: eb fc jmp -4 <.plt+0x2b>
// CHECK-NEXT: 1103f: 90 nop // CHECK-NEXT: 1103f: 90 nop
// CHECK-NEXT: 11040: 68 00 00 00 00 pushl $0 // CHECK-NEXT: 11040: 68 00 00 00 00 pushl $0
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lld/test/ELF/i386-retpoline-pic.s

// REQUIRES: x86 // REQUIRES: x86
// RUN: llvm-mc -filetype=obj -triple=i386-unknown-linux -position-independent %s -o %t1.o // RUN: llvm-mc -filetype=obj -triple=i386-unknown-linux -position-independent %s -o %t1.o
// RUN: llvm-mc -filetype=obj -triple=i386-unknown-linux -position-independent %p/Inputs/shared.s -o %t2.o // RUN: llvm-mc -filetype=obj -triple=i386-unknown-linux -position-independent %p/Inputs/shared.s -o %t2.o
// RUN: ld.lld -shared %t2.o -o %t2.so // RUN: ld.lld -shared %t2.o -o %t2.so
// RUN: ld.lld %t1.o %t2.so -o %t.exe -z retpolineplt -pie // RUN: ld.lld %t1.o %t2.so -o %t.exe -z retpolineplt -pie
// RUN: llvm-objdump -d %t.exe | FileCheck %s // RUN: llvm-objdump -d %t.exe | FileCheck %s
// CHECK: 1010: 50 pushl %eax // CHECK: 1010: 50 pushl %eax
// CHECK-NEXT: 1011: 8b 83 08 20 00 00 movl 8200(%ebx), %eax // CHECK-NEXT: 1011: 8b 83 08 20 00 00 movl 8200(%ebx), %eax
// CHECK-NEXT: 1017: e8 04 00 00 00 calll 4 <.plt+0x10> // CHECK-NEXT: 1017: e8 04 00 00 00 calll 4 <.plt+0x10>
// CHECK-NEXT: 101c: f3 90 pause // CHECK-NEXT: 101c: f3 90 pause
// CHECK-NEXT: 101e: eb fc jmp -4 <.plt+0xc> // CHECK-NEXT: 101e: eb fc jmp -4 <.plt+0xc>
// CHECK-NEXT: 1020: 83 c4 04 addl $4, %esp // CHECK-NEXT: 1020: 89 0c 24 movl %ecx, (%esp)
// CHECK-NEXT: 1023: 87 04 24 xchgl %eax, (%esp) // CHECK-NEXT: 1023: 8b 4c 24 04 movl 4(%esp), %ecx
// CHECK-NEXT: 1026: c3 retl // CHECK-NEXT: 1027: 89 44 24 04 movl %eax, 4(%esp)
// CHECK-NEXT: 1027: cc int3 // CHECK-NEXT: 102b: 89 c8 movl %ecx, %eax
// CHECK-NEXT: 1028: cc int3 // CHECK-NEXT: 102d: 59 popl %ecx
// CHECK-NEXT: 1029: cc int3 // CHECK-NEXT: 102e: c3 retl
// CHECK-NEXT: 102a: cc int3
// CHECK-NEXT: 102b: cc int3
// CHECK-NEXT: 102c: cc int3
// CHECK-NEXT: 102d: cc int3
// CHECK-NEXT: 102e: cc int3
// CHECK-NEXT: 102f: cc int3 // CHECK-NEXT: 102f: cc int3
// CHECK-NEXT: 1030: 50 pushl %eax // CHECK-NEXT: 1030: 50 pushl %eax
// CHECK-NEXT: 1031: 8b 83 0c 20 00 00 movl 8204(%ebx), %eax // CHECK-NEXT: 1031: 8b 83 0c 20 00 00 movl 8204(%ebx), %eax
// CHECK-NEXT: 1037: e8 e4 ff ff ff calll -28 <.plt+0x10> // CHECK-NEXT: 1037: e8 e4 ff ff ff calll -28 <.plt+0x10>
// CHECK-NEXT: 103c: f3 90 pause // CHECK-NEXT: 103c: f3 90 pause
// CHECK-NEXT: 103e: eb fc jmp -4 <.plt+0x2c> // CHECK-NEXT: 103e: eb fc jmp -4 <.plt+0x2c>
// CHECK-NEXT: 1040: 68 00 00 00 00 pushl $0 // CHECK-NEXT: 1040: 68 00 00 00 00 pushl $0
// CHECK-NEXT: 1045: ff b3 04 20 00 00 pushl 8196(%ebx) // CHECK-NEXT: 1045: ff b3 04 20 00 00 pushl 8196(%ebx)
Show All 14 Lines

lld/test/ELF/x86-64-retpoline.s

// REQUIRES: x86 // REQUIRES: x86
// RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t1.o // RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t1.o
// RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %p/Inputs/shared.s -o %t2.o // RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %p/Inputs/shared.s -o %t2.o
// RUN: ld.lld -shared %t2.o -o %t2.so // RUN: ld.lld -shared %t2.o -o %t2.so
// RUN: ld.lld -shared %t1.o %t2.so -o %t.exe -z retpolineplt // RUN: ld.lld -shared %t1.o %t2.so -o %t.exe -z retpolineplt
// RUN: llvm-objdump -d %t.exe | FileCheck %s // RUN: llvm-objdump -d %t.exe | FileCheck %s
// CHECK: 1010: ff 35 f2 0f 00 00 pushq 4082(%rip) // CHECK: 1010: 4c 8b 1d f9 0f 00 00 movq 4089(%rip), %r11
// CHECK-NEXT: 1016: 4c 8b 1d f3 0f 00 00 movq 4083(%rip), %r11 // CHECK-NEXT: 1017: e8 04 00 00 00 callq 4 <.plt+0x10>
// CHECK-NEXT: 101d: e8 0e 00 00 00 callq 14 <.plt+0x20> // CHECK-NEXT: 101c: f3 90 pause
// CHECK-NEXT: 1022: f3 90 pause // CHECK-NEXT: 101e: eb fc jmp -4 <.plt+0xc>
// CHECK-NEXT: 1024: eb fc jmp -4 <.plt+0x12> // CHECK-NEXT: 1020: 4c 89 1c 24 movq %r11, (%rsp)
// CHECK-NEXT: 1026: 0f 1f 44 00 00 nopl // CHECK-NEXT: 1024: c3 retq
// CHECK-NEXT: 102b: 0f 1f 44 00 00 nopl // CHECK-NEXT: 1025: cc int3
// CHECK-NEXT: 1030: 4c 89 1c 24 movq %r11, (%rsp) // CHECK-NEXT: 1026: cc int3
// CHECK-NEXT: 1034: c3 retq // CHECK-NEXT: 1027: cc int3
// CHECK-NEXT: 1035: cc int3 // CHECK-NEXT: 1028: cc int3
// CHECK-NEXT: 1036: cc int3 // CHECK-NEXT: 1029: cc int3
// CHECK-NEXT: 1037: cc int3 // CHECK-NEXT: 102a: cc int3
// CHECK-NEXT: 1038: cc int3 // CHECK-NEXT: 102b: cc int3
// CHECK-NEXT: 1039: cc int3 // CHECK-NEXT: 102c: cc int3
// CHECK-NEXT: 103a: cc int3 // CHECK-NEXT: 102d: cc int3
// CHECK-NEXT: 103b: cc int3 // CHECK-NEXT: 102e: cc int3
// CHECK-NEXT: 103c: cc int3 // CHECK-NEXT: 102f: cc int3
// CHECK-NEXT: 103d: cc int3 // CHECK-NEXT: 1030: 4c 8b 1d e1 0f 00 00 movq 4065(%rip), %r11
// CHECK-NEXT: 103e: cc int3 // CHECK-NEXT: 1037: e8 e4 ff ff ff callq -28 <.plt+0x10>
// CHECK-NEXT: 103f: cc int3 // CHECK-NEXT: 103c: f3 90 pause
// CHECK-NEXT: 1040: 4c 8b 1d d1 0f 00 00 movq 4049(%rip), %r11 // CHECK-NEXT: 103e: eb fc jmp -4 <.plt+0x2c>
// CHECK-NEXT: 1047: e8 04 00 00 00 callq 4 <.plt+0x40> // CHECK-NEXT: 1040: 68 00 00 00 00 pushq $0
// CHECK-NEXT: 104c: f3 90 pause // CHECK-NEXT: 1045: ff 35 bd 0f 00 00 pushq 4029(%rip)
// CHECK-NEXT: 104e: eb fc jmp -4 <.plt+0x3c> // CHECK-NEXT: 104b: e9 c0 ff ff ff jmp -64 <.plt>
// CHECK-NEXT: 1050: 4c 89 1c 24 movq %r11, (%rsp) // CHECK-NEXT: 1050: 4c 8b 1d c9 0f 00 00 movq 4041(%rip), %r11
// CHECK-NEXT: 1054: c3 retq // CHECK-NEXT: 1057: e8 c4 ff ff ff callq -60 <.plt+0x10>
// CHECK-NEXT: 1055: 68 00 00 00 00 pushq $0 // CHECK-NEXT: 105c: f3 90 pause
// CHECK-NEXT: 105a: e9 b1 ff ff ff jmp -79 <.plt> // CHECK-NEXT: 105e: eb fc jmp -4 <.plt+0x4c>
// CHECK-NEXT: 105f: cc int3 // CHECK-NEXT: 1060: 68 01 00 00 00 pushq $1
// CHECK-NEXT: 1060: 4c 8b 1d b9 0f 00 00 movq 4025(%rip), %r11 // CHECK-NEXT: 1065: ff 35 9d 0f 00 00 pushq 3997(%rip)
// CHECK-NEXT: 1067: e8 04 00 00 00 callq 4 <.plt+0x60> // CHECK-NEXT: 106b: e9 a0 ff ff ff jmp -96 <.plt>
// CHECK-NEXT: 106c: f3 90 pause
// CHECK-NEXT: 106e: eb fc jmp -4 <.plt+0x5c>
// CHECK-NEXT: 1070: 4c 89 1c 24 movq %r11, (%rsp)
// CHECK-NEXT: 1074: c3 retq
// CHECK-NEXT: 1075: 68 01 00 00 00 pushq $1
// CHECK-NEXT: 107a: e9 91 ff ff ff jmp -111 <.plt>
// CHECK-NEXT: 107f: cc int3
.global _start .global _start
_start: _start:
jmp bar@PLT jmp bar@PLT
jmp zed@PLT jmp zed@PLT