lld/test/COFF/comdat-jumptable.s

   1 # REQUIRES: x86
   2 # RUN: llvm-mc -triple=x86_64-windows-gnu %s -filetype=obj -o %t1.obj
   3 # RUN: llvm-mc -triple=x86_64-windows-gnu %S/Inputs/comdat-jumptable2.s -filetype=obj -o %t2.obj
   4
   5 # RUN: llvm-objdump -s %t1.obj | FileCheck --check-prefix=OBJ1 %s
   6 # RUN: llvm-objdump -s %t2.obj | FileCheck --check-prefix=OBJ2 %s
   7
   8 # RUN: lld-link -lldmingw -entry:main %t1.obj %t2.obj -out:%t.exe
   9 # RUN: llvm-objdump -s %t.exe | FileCheck --check-prefix=EXE %s
  10
  11 # Test linking cases where comdat functions have an associated jump table
  12 # in a non-comdat rdata (which GCC produces for functions with jump tables).
  13 # In these cases, ld.bfd keeps all rdata sections, but the relocations that
  14 # refer to discarded comdat sections just are emitted as they were originally.
  15
  16 # In real scenarios, the jump table .rdata section should be identical across
  17 # all object files; here it is different to illustrate more clearly what
  18 # the linker actually does.
  19
  20 # OBJ1: Contents of section .rdata:
  21 # OBJ1:  0000 aaaaaaaa 14000000 1e000000 28000000
  22 # OBJ1:  0010 bbbbbbbb
  23
  24 # OBJ2: Contents of section .rdata:
  25 # OBJ2:  0000 cccccccc 14000000 1e000000 28000000
  26 # OBJ2:  0010 dddddddd
  27
  28 # EXE: Contents of section .rdata:
  29 # EXE:  140002000 aaaaaaaa 0c100000 12100000 18100000
  30 # EXE:  140002010 bbbbbbbb cccccccc 14000000 1e000000
  31 # EXE:  140002020 28000000 dddddddd
  32
  33
  34         .section .text@comdatfunc, "x"
  35         .linkonce discard
  36         .globl comdatfunc
  37 comdatfunc:
  38         leaq .Ljumptable(%rip), %rax
  39         movslq (%rax, %rcx, 4), %rcx
  40         addq %rcx, %rax
  41         jmp *%rax
  42
  43         .section .rdata, "dr"
  44         .long 0xaaaaaaaa
  45 .Ljumptable:
  46         .long .Ltail1-.Ljumptable
  47         .long .Ltail2-.Ljumptable
  48         .long .Ltail3-.Ljumptable
  49         .long 0xbbbbbbbb
  50
  51         .section .text@comdatfunc, "x"
  52 # If assembled with binutils, the following line can be kept in:
  53 #       .linkonce discard
  54 .Ltail1:
  55         movl $1, %eax
  56         ret
  57 .Ltail2:
  58         movl $2, %eax
  59         ret
  60 .Ltail3:
  61         movl $3, %eax
  62         ret
  63
  64
  65         .text
  66         .globl main
  67 main:
  68         call comdatfunc
  69         call otherfunc
  70         ret