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| # REQUIRES: aarch64
# RUN: llvm-mc -filetype=obj -triple=aarch64-none-linux-gnu %s -o %t.o
# RUN: ld.lld %t.o -o %t
# RUN: llvm-objdump -d --no-show-raw-insn %t | FileCheck %s --check-prefix=PDE
# RUN: llvm-readobj -r %t | FileCheck %s --check-prefix=PDE-RELOC
# RUN: ld.lld -pie %t.o -o %t
# RUN: llvm-objdump -d --no-show-raw-insn %t | FileCheck %s --check-prefix=PIE
# RUN: llvm-readobj -r %t | FileCheck %s --check-prefix=PIE-RELOC
## When compiling with -fno-PIE or -fPIE, if the ifunc is in the same
## translation unit as the address taker, the compiler knows that ifunc is not
## defined in a shared library so it can use a non GOT generating relative reference.
.text
.globl myfunc
.type myfunc,@gnu_indirect_function
myfunc:
.globl myfunc_resolver
.type myfunc_resolver,@function
myfunc_resolver:
ret
.text
.globl main
.type main,@function
main:
adrp x8, myfunc
add x8, x8, :lo12: myfunc
ret
## The address of myfunc is the address of the PLT entry for myfunc.
# PDE: myfunc_resolver:
# PDE-NEXT: 210170: ret
# PDE: main:
# PDE-NEXT: 210174: adrp x8, #0
# PDE-NEXT: 210178: add x8, x8, #384
# PDE-NEXT: 21017c: ret
# PDE-EMPTY:
# PDE-NEXT: Disassembly of section .plt:
# PDE-EMPTY:
# PDE-NEXT: myfunc:
## page(.got.plt) - page(0x210010) = 65536
# PDE-NEXT: 210180: adrp x16, #65536
# PDE-NEXT: 210184: ldr x17, [x16, #400]
# PDE-NEXT: 210188: add x16, x16, #400
# PDE-NEXT: 21018c: br x17
## The adrp to myfunc should generate a PLT entry and a GOT entry with an
## irelative relocation.
# PDE-RELOC: .rela.dyn {
# PDE-RELOC-NEXT: 0x220190 R_AARCH64_IRELATIVE - 0x210170
# PDE-RELOC-NEXT: }
# PIE: myfunc_resolver:
# PIE-NEXT: 10260: ret
# PIE: main:
# PIE-NEXT: 10264: adrp x8, #0
# PIE-NEXT: 10268: add x8, x8, #624
# PIE-NEXT: 1026c: ret
# PIE-EMPTY:
# PIE-NEXT: Disassembly of section .plt:
# PIE-EMPTY:
# PIE-NEXT: myfunc:
# PIE-NEXT: 10270: adrp x16, #131072
# PIE-NEXT: 10274: ldr x17, [x16, #880]
# PIE-NEXT: 10278: add x16, x16, #880
# PIE-NEXT: 1027c: br x17
# PIE-RELOC: .rela.dyn {
# PIE-RELOC-NEXT: 0x30370 R_AARCH64_IRELATIVE - 0x10260
# PIE-RELOC-NEXT: }
|