gnu-ifunc-plt.s
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// REQUIRES: x86
/// For non-preemptable ifunc, place ifunc PLT entries to the .iplt section.
// RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %S/Inputs/shared2-x86-64.s -o %t1.o
// RUN: ld.lld %t1.o --shared -soname=so -o %t.so
// RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t.o
// RUN: ld.lld --hash-style=sysv %t.so %t.o -o %tout
// RUN: llvm-objdump -d --no-show-raw-insn --print-imm-hex %tout | FileCheck %s --check-prefix=DISASM
// RUN: llvm-objdump -s %tout | FileCheck %s --check-prefix=GOTPLT
// RUN: llvm-readobj -r --dynamic-table %tout | FileCheck %s
/// Check that the PLTRELSZ tag does not include the IRELATIVE relocations
// CHECK: DynamicSection [
// CHECK: 0x0000000000000008 RELASZ 72 (bytes)
// CHECK: 0x0000000000000002 PLTRELSZ 48 (bytes)
/// Check that the IRELATIVE relocations are placed to the .rela.dyn section after
/// other regular relocations (e.g. GLOB_DAT).
// CHECK: Relocations [
// CHECK-NEXT: Section (4) .rela.dyn {
// CHECK-NEXT: 0x202480 R_X86_64_GLOB_DAT bar3 0x0
// CHECK-NEXT: 0x2034B0 R_X86_64_IRELATIVE - 0x201318
// CHECK-NEXT: 0x2034B8 R_X86_64_IRELATIVE - 0x201319
// CHECK-NEXT: }
// CHECK-NEXT: Section (5) .rela.plt {
// CHECK-NEXT: 0x2034A0 R_X86_64_JUMP_SLOT bar2 0x0
// CHECK-NEXT: 0x2034A8 R_X86_64_JUMP_SLOT zed2 0x0
// CHECK-NEXT: }
/// Check that .got.plt entries point back to PLT header
// GOTPLT: Contents of section .got.plt:
// GOTPLT-NEXT: 203488 90232000 00000000 00000000 00000000
// GOTPLT-NEXT: 203498 00000000 00000000 56132000 00000000
// GOTPLT-NEXT: 2034a8 66132000 00000000 00000000 00000000
// GOTPLT-NEXT: 2034b8 00000000 00000000
/// Check that we have 2 PLT sections: one regular .plt section and one
/// .iplt section for ifunc entries.
// DISASM: Disassembly of section .text:
// DISASM-EMPTY:
// DISASM-NEXT: <foo>:
// DISASM-NEXT: 201318: retq
// DISASM: <bar>:
// DISASM-NEXT: 201319: retq
// DISASM: <_start>:
// DISASM-NEXT: 20131a: callq 0x201370
// DISASM-NEXT: 20131f: callq 0x201380
// DISASM-NEXT: callq {{.*}} <bar2@plt>
// DISASM-NEXT: callq {{.*}} <zed2@plt>
// DISASM-NEXT: jmpq *0x114c(%rip)
// DISASM-EMPTY:
// DISASM-NEXT: Disassembly of section .plt:
// DISASM-EMPTY:
// DISASM-NEXT: <.plt>:
// DISASM-NEXT: 201340: pushq 0x214a(%rip)
// DISASM-NEXT: 201346: jmpq *0x214c(%rip)
// DISASM-NEXT: 20134c: nopl (%rax)
// DISASM-EMPTY:
// DISASM-NEXT: <bar2@plt>:
// DISASM-NEXT: 201350: jmpq *0x214a(%rip)
// DISASM-NEXT: 201356: pushq $0x0
// DISASM-NEXT: 20135b: jmp 0x201340 <.plt>
// DISASM-EMPTY:
// DISASM-NEXT: <zed2@plt>:
// DISASM-NEXT: 201360: jmpq *0x2142(%rip)
// DISASM-NEXT: 201366: pushq $0x1
// DISASM-NEXT: 20136b: jmp 0x201340 <.plt>
// DISASM-EMPTY:
// DISASM-NEXT: Disassembly of section .iplt:
// DISASM-EMPTY:
// DISASM-NEXT: <.iplt>:
// DISASM-NEXT: 201370: jmpq *0x213a(%rip)
// DISASM-NEXT: 201376: pushq $0x0
// DISASM-NEXT: 20137b: jmp 0x201340 <.plt>
// DISASM-NEXT: 201380: jmpq *0x2132(%rip)
// DISASM-NEXT: 201386: pushq $0x1
// DISASM-NEXT: 20138b: jmp 0x201340 <.plt>
// Test that --shuffle-sections does not affect the order of relocations and that
// we still place IRELATIVE relocations last. Check both random seed (0) and an
// arbitrary seed that was known to break the order of relocations previously (3).
// RUN: ld.lld --shuffle-sections=3 %t.so %t.o -o %tout2
// RUN: llvm-readobj --relocations %tout2 | FileCheck %s --check-prefix=SHUFFLE
// RUN: ld.lld --shuffle-sections=0 %t.so %t.o -o %tout3
// RUN: llvm-readobj --relocations %tout3 | FileCheck %s --check-prefix=SHUFFLE
// SHUFFLE: Section {{.*}} .rela.dyn {
// SHUFFLE-NEXT: R_X86_64_GLOB_DAT
// SHUFFLE-NEXT: R_X86_64_IRELATIVE
// SHUFFLE-NEXT: R_X86_64_IRELATIVE
// SHUFFLE-NEXT: }
.text
.type foo STT_GNU_IFUNC
.globl foo
foo:
ret
.type bar STT_GNU_IFUNC
.globl bar
bar:
ret
.globl _start
_start:
call foo
call bar
call bar2
call zed2
jmp *bar3@GOTPCREL(%rip)