lld/test/MachO/alias-symbols.s

   1 # REQUIRES: x86
   2 # RUN: rm -rf %t; split-file %s %t
   3 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/aliases.s -o %t/aliases.o
   4 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/definitions.s -o %t/definitions.o
   5 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/weak-extern-alias-to-weak.s -o %t/weak-extern-alias-to-weak.o
   6 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/weak-extern-alias-to-strong.s -o %t/weak-extern-alias-to-strong.o
   7
   8 # RUN: %lld -lSystem %t/aliases.o %t/definitions.o -o %t/out
   9 # RUN: llvm-objdump --macho --syms %t/out | FileCheck %s
  10
  11 ## local aliases should be dropped entirely. --implicit-check-not doesn't seem
  12 ## to work well with -DAG matches, so we check for _local_alias' absence in a
  13 ## separate step.
  14 # RUN: llvm-objdump --macho --syms %t/out | FileCheck /dev/null --implicit-check-not _local_alias
  15
  16 # CHECK-DAG: [[#%.16x,STRONG:]] g     F __TEXT,__text _strong
  17 # CHECK-DAG: [[#%.16x,WEAK_1:]]  w    F __TEXT,__text _weak_1
  18 # CHECK-DAG: [[#%.16x,PEXT:]]   l     F __TEXT,__text .hidden _pext
  19 # CHECK-DAG: [[#%.16x,DEAD:]]   g     F __TEXT,__text _dead
  20 # CHECK-DAG: [[#STRONG]]        l     F __TEXT,__text .hidden _pext_alias
  21 # CHECK-DAG: [[#PEXT]]          l     F __TEXT,__text .hidden _alias_to_pext
  22 # CHECK-DAG: [[#STRONG]]        g     F __TEXT,__text _extern_alias_to_strong
  23 # CHECK-DAG: [[#WEAK_1]]         w    F __TEXT,__text _weak_extern_alias_to_weak
  24 # CHECK-DAG: [[#DEAD]]          g     F __TEXT,__text _no_dead_strip_alias
  25 # CHECK-DAG: [[#STRONG]]        g     F __TEXT,__text _weak_extern_alias_to_strong
  26
  27 # RUN: %lld -lSystem -dead_strip %t/aliases.o %t/definitions.o -o %t/dead-stripped
  28 # RUN: llvm-objdump --macho --syms %t/dead-stripped | FileCheck %s --check-prefix=STRIPPED
  29
  30 # STRIPPED:       SYMBOL TABLE:
  31 # STRIPPED-NEXT:  g     F __TEXT,__text _main
  32 # STRIPPED-NEXT:  g     F __TEXT,__text __mh_execute_header
  33 # STRIPPED-NEXT:          *UND* dyld_stub_binder
  34 # STRIPPED-EMPTY:
  35
  36 # RUN: not %lld -lSystem %t/aliases.o %t/definitions.o \
  37 # RUN:   %t/weak-extern-alias-to-strong.o -o /dev/null 2>&1
  38
  39 ## Verify that we preserve the file names of the aliases, rather than using the
  40 ## filename of the aliased symbols.
  41 # DUP:      error: duplicate symbol: _weak_extern_alias_to_weak
  42 # DUP-NEXT: >>> defined in {{.*}}aliases.o
  43 # DUP-NEXT: >>> defined in {{.*}}weak-extern-alias-to-weak.o
  44
  45 ## The following cases are actually all dup symbol errors under ld64. Alias
  46 ## symbols are treated like strong extern symbols by ld64 even if the symbol they alias
  47 ## is actually weak. LLD OTOH does not check for dup symbols until after
  48 ## resolving the aliases; this makes for a simpler implementation.
  49 ## The following test cases are meant to elucidate what LLD's behavior is, but
  50 ## we should feel free to change it in the future should it be helpful for the
  51 ## implementation.
  52
  53 # RUN: %lld -lSystem %t/aliases.o %t/definitions.o \
  54 # RUN:   %t/weak-extern-alias-to-weak.o -o %t/alias-clash-1
  55 # RUN: llvm-objdump --macho --syms %t/alias-clash-1 | FileCheck %s --check-prefix WEAK-1
  56
  57 # RUN: %lld -lSystem %t/weak-extern-alias-to-weak.o %t/aliases.o \
  58 # RUN:   %t/definitions.o -o %t/alias-clash-2
  59 # RUN: llvm-objdump --macho --syms %t/alias-clash-2 | FileCheck %s --check-prefix WEAK-2
  60
  61 # RUN: %lld -lSystem %t/aliases.o %t/definitions.o \
  62 # RUN:   -alias _weak_2 _weak_extern_alias_to_weak -o %t/opt-vs-symbol
  63 # RUN: llvm-objdump --macho --syms %t/opt-vs-symbol | FileCheck %s --check-prefix WEAK-2
  64
  65 # RUN: %lld -lSystem -alias _weak_2 _weak_extern_alias_to_weak %t/aliases.o \
  66 # RUN:   %t/definitions.o -o %t/opt-vs-symbol
  67 # RUN: llvm-objdump --macho --syms %t/opt-vs-symbol | FileCheck %s --check-prefix WEAK-2
  68
  69 # WEAK-1-DAG: [[#%.16x,WEAK_1:]]  w    F __TEXT,__text _weak_1
  70 # WEAK-1-DAG: [[#WEAK_1]]         w    F __TEXT,__text _weak_extern_alias_to_weak
  71
  72 # WEAK-2-DAG: [[#%.16x,WEAK_2:]]  w    F __TEXT,__text _weak_2
  73 # WEAK-2-DAG: [[#WEAK_2]]         w    F __TEXT,__text _weak_extern_alias_to_weak
  74
  75 #--- aliases.s
  76 .globl _extern_alias_to_strong, _weak_extern_alias_to_weak
  77 .weak_definition _weak_extern_alias_to_weak
  78
  79 ## Private extern aliases result in local symbols in the output (i.e. it is as
  80 ## if the aliased symbol is also private extern.)
  81 .private_extern _pext_alias
  82
  83 ## This test case demonstrates that it doesn't matter whether the alias itself
  84 ## is strong or weak. Rather, what matters is whether the aliased symbol is
  85 ## strong or weak.
  86 .globl _weak_extern_alias_to_strong
  87 .weak_definition _weak_extern_alias_to_strong
  88
  89 ## no_dead_strip doesn't retain the aliased symbol if it is dead
  90 .globl _no_dead_strip_alias
  91 .no_dead_strip _no_dead_strip_alias
  92
  93 .globl _alias_to_pext
  94 _alias_to_pext = _pext
  95
  96 _extern_alias_to_strong = _strong
  97 _weak_extern_alias_to_weak = _weak_1
  98 _weak_extern_alias_to_strong = _strong
  99
 100 _pext_alias = _strong
 101 _local_alias = _strong
 102 _no_dead_strip_alias = _dead
 103
 104 .subsections_via_symbols
 105
 106 #--- weak-extern-alias-to-weak.s
 107 .globl _weak_extern_alias_to_weak
 108 .weak_definition _weak_extern_alias_to_weak
 109 _weak_extern_alias_to_weak = _weak_2
 110
 111 #--- weak-extern-alias-to-strong.s
 112 .globl _weak_extern_alias_to_strong
 113 .weak_definition _weak_extern_alias_to_strong
 114 _weak_extern_alias_to_strong = _strong
 115
 116 #--- definitions.s
 117 .globl _strong, _weak_1, _weak_2, _dead
 118 .private_extern _pext
 119 .weak_definition _weak_1
 120 .weak_definition _weak_2
 121
 122 _strong:
 123   .space 1
 124 _weak_1:
 125   .space 1
 126 _weak_2:
 127   .space 1
 128 _dead:
 129   .space 1
 130 _pext:
 131   .space 1
 132
 133 .globl _main
 134 _main:
 135
 136 .subsections_via_symbols