comdat-jumptable.s
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# REQUIRES: x86
# RUN: llvm-mc -triple=x86_64-windows-gnu %s -filetype=obj -o %t1.obj
# RUN: llvm-mc -triple=x86_64-windows-gnu %S/Inputs/comdat-jumptable2.s -filetype=obj -o %t2.obj
# RUN: llvm-objdump -s %t1.obj | FileCheck --check-prefix=OBJ1 %s
# RUN: llvm-objdump -s %t2.obj | FileCheck --check-prefix=OBJ2 %s
# RUN: lld-link -lldmingw -entry:main %t1.obj %t2.obj -out:%t.exe
# RUN: llvm-objdump -s %t.exe | FileCheck --check-prefix=EXE %s
# Test linking cases where comdat functions have an associated jump table
# in a non-comdat rdata (which GCC produces for functions with jump tables).
# In these cases, ld.bfd keeps all rdata sections, but the relocations that
# refer to discarded comdat sections just are emitted as they were originally.
# In real scenarios, the jump table .rdata section should be identical across
# all object files; here it is different to illustrate more clearly what
# the linker actually does.
# OBJ1: Contents of section .rdata:
# OBJ1: 0000 aaaaaaaa 14000000 1e000000 28000000
# OBJ1: 0010 bbbbbbbb
# OBJ2: Contents of section .rdata:
# OBJ2: 0000 cccccccc 14000000 1e000000 28000000
# OBJ2: 0010 dddddddd
# EXE: Contents of section .rdata:
# EXE: 140002000 aaaaaaaa 0c100000 12100000 18100000
# EXE: 140002010 bbbbbbbb cccccccc 14000000 1e000000
# EXE: 140002020 28000000 dddddddd
.section .text@comdatfunc, "x"
.linkonce discard
.globl comdatfunc
comdatfunc:
leaq .Ljumptable(%rip), %rax
movslq (%rax, %rcx, 4), %rcx
addq %rcx, %rax
jmp *%rax
.section .rdata, "dr"
.long 0xaaaaaaaa
.Ljumptable:
.long .Ltail1-.Ljumptable
.long .Ltail2-.Ljumptable
.long .Ltail3-.Ljumptable
.long 0xbbbbbbbb
.section .text@comdatfunc, "x"
# If assembled with binutils, the following line can be kept in:
# .linkonce discard
.Ltail1:
movl $1, %eax
ret
.Ltail2:
movl $2, %eax
ret
.Ltail3:
movl $3, %eax
ret
.text
.globl main
main:
call comdatfunc
call otherfunc
ret