lld/test/ELF/arm-exidx-nonzero-offset.s

   1 // REQUIRES: arm
   2 // RUN: rm -rf %t && split-file %s %t
   3
   4 // RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi --arm-add-build-attributes %t/a.s -o %t/a.o
   5 // RUN: ld.lld %t/a.o -T %t/exidx-non-zero-offset.t -o %t/non-zero
   6 // RUN: llvm-readelf --program-headers --unwind --symbols -x .exceptions %t/non-zero | FileCheck %s
   7 // RUN: ld.lld %t/a.o -T %t/exidx-zero-offset.t -o %t/zero
   8 // RUN: llvm-readelf --program-headers --unwind --symbols -x .exceptions %t/zero | FileCheck %s
   9
  10 /// On platforms that load ELF files directly the ARM.exidx sections
  11 /// are located with the PT_ARM_EXIDX program header. This requires
  12 /// all .ARM.exidx input sections to be placed in a single
  13 /// .ARM.exidx output section. Embedded systems that do not load
  14 /// from an ELF file use the linker defined symbols __exidx_start and
  15 /// __exidx_stop. There is no requirement to place the .ARM.exidx
  16 /// input sections in their own output section. This test case checks
  17 /// that a .ARM.exidx synthetic section that isn't at a zero offset
  18 /// within the output section gets the correct offsets. We check
  19 /// this by checking that equal amounts of alignment padding
  20 /// inserted before and after the section start produce the same
  21 /// results.
  22
  23 /// For the two linker scripts, one with the .ARM.exidx table
  24 /// at a zero offset within its output section and one with a
  25 /// non-zero offset, but both at the same file and address;
  26 /// the PT_ARM_EXIDX, symbols and table contents should be the
  27 /// same.
  28 // CHECK:      EXIDX 0x010080 0x00000080 0x00000080 0x00028 0x00028 R   0x4
  29
  30 /// unwind entries starting from the right address are identical.
  31 /// llvm-readelf does not seem to be able to detect Thumb functionNames
  32 /// whereas arm-none-eabi-readelf can. Used CHECK rather than CHECK-NEXT
  33 /// to cope with possible improvements llvm-readelf.
  34 // CHECK:        FunctionAddress: 0x0
  35 // CHECK-NEXT:   FunctionName: f1
  36 // CHECK-NEXT:   Model: Compact (Inline)
  37 // CHECK-NEXT:   PersonalityIndex: 0
  38 // CHECK-NEXT:   Opcodes [
  39 // CHECK-NEXT:     0x97      ; vsp = r7
  40 // CHECK-NEXT:     0x84 0x08 ; pop {r7, lr}
  41 // CHECK-NEXT:   ]
  42 // CHECK-NEXT: }
  43 // CHECK-NEXT: Entry {
  44 // CHECK-NEXT:   FunctionAddress: 0x8
  45 // CHECK-NEXT:   FunctionName: f2
  46 // CHECK-NEXT:   Model: CantUnwind
  47 // CHECK-NEXT: }
  48 // CHECK-NEXT: Entry {
  49 // CHECK-NEXT:   FunctionAddress: 0xE
  50 // CHECK:        ExceptionHandlingTable: .ARM.extab
  51 // CHECK-NEXT:   TableEntryAddress: 0xA8
  52 // CHECK-NEXT:   Model: Generic
  53 // CHECK-NEXT:   PersonalityRoutineAddress: 0x12
  54 // CHECK-NEXT: }
  55 // CHECK-NEXT: Entry {
  56 // CHECK-NEXT:   FunctionAddress: 0x10
  57 // CHECK:        Model: CantUnwind
  58 // CHECK-NEXT: }
  59 // CHECK-NEXT: Entry {
  60 // CHECK-NEXT:   FunctionAddress: 0x14
  61 // CHECK-NEXT:   FunctionName: __ARMv7ABSLongThunk_f3
  62 // CHECK-NEXT:   Model: CantUnwind
  63 // CHECK-NEXT: }
  64
  65 // CHECK:      {{[0-9]+}}: 00000080 {{.*}} __exidx_start
  66 // CHECK-NEXT: {{[0-9]+}}: 000000a8 {{.*}} __exidx_end
  67
  68 // CHECK:      0x00000080 80ffff7f 08849780 80ffff7f 01000000
  69 // CHECK-NEXT: 0x00000090 7effff7f 14000000 78ffff7f 01000000
  70 // CHECK-NEXT: 0x000000a0 74ffff7f 01000000
  71
  72 //--- exidx-non-zero-offset.t
  73 SECTIONS {
  74   .text : { *(.text .text.*) }
  75   /* Addition of thunk in .text changes alignment padding */
  76   .exceptions : {
  77   /* Alignment padding within .exceptions */
  78   . = ALIGN(128);
  79   /* Embedded C libraries find exceptions via linker defined
  80      symbols */
  81   __exidx_start = .;
  82   *(.ARM.exidx) ;
  83   __exidx_end = .;
  84   }
  85   .ARM.extab : { *(.ARM.extab .ARM.extab.*) }
  86 }
  87
  88 //--- exidx-zero-offset.t
  89 SECTIONS {
  90   .text : { *(.text .text.*) }
  91   /* Addition of thunk in .text changes alignment padding */
  92   /* alignment padding before .exceptions starts */
  93   .exceptions : ALIGN(128) {
  94   /* Embedded C libraries find exceptions via linker defined
  95      symbols */
  96   __exidx_start = .;
  97   *(.ARM.exidx) ;
  98   __exidx_end = .;
  99   }
 100   .ARM.extab : { *(.ARM.extab .ARM.extab.*) }
 101 }
 102
 103 //--- a.s
 104 .syntax unified
 105
 106 /// Expect inline unwind instructions.
 107 .section .text.01, "ax", %progbits
 108 .arm
 109 .balign 4
 110 .global f1
 111 .type f1, %function
 112 f1:
 113 .fnstart
 114 /// provoke an interworking thunk.
 115 b f3
 116 bx lr
 117 .save {r7, lr}
 118 .setfp r7, sp, #0
 119 .fnend
 120
 121 /// Expect no unwind information from assembler. The linker must
 122 /// synthesise an EXIDX_CANTUNWIND entry to prevent an exception
 123 /// thrown through f2 from matching against the unwind instructions
 124 /// for f1.
 125 .section .text.02, "ax", %progbits
 126 .global f2
 127 .type f2, %function
 128 .balign 4
 129 f2:
 130 bx lr
 131
 132 /// Expect 1 EXIDX_CANTUNWIND entry that can be merged into the linker
 133 /// generated EXIDX_CANTUNWIND as if the assembler had generated it.
 134 .section .text.03, "ax",%progbits
 135 .global f3
 136 .type f3, %function
 137 .thumb
 138 .balign 2
 139 f3:
 140 .fnstart
 141 bx lr
 142 .cantunwind
 143 .fnend
 144
 145 /// Expect a section with a reference to an .ARM.extab.
 146 .section .text.04, "ax",%progbits
 147 .global f4
 148 .balign 2
 149 .type f4, %function
 150 f4:
 151 .fnstart
 152 bx lr
 153 .personality __gxx_personality_v0
 154 .handlerdata
 155 .long 0
 156 .fnend
 157
 158
 159 /// Dummy implementation of personality routines to satisfy reference
 160 /// from exception tables, linker will generate EXIDX_CANTUNWIND.
 161 .section .text.__aeabi_unwind_cpp_pr0, "ax", %progbits
 162 .global __aeabi_unwind_cpp_pr0
 163 .type __aeabi_unwind_cpp_pr0, %function
 164 .balign 2
 165 __aeabi_unwind_cpp_pr0:
 166 bx lr
 167
 168 .section .text.__gcc_personality_v0, "ax", %progbits
 169 .global __gxx_personality_v0
 170 .type __gcc_personality_v0, %function
 171 .balign 2
 172 __gxx_personality_v0:
 173 bx lr