lld/test/ELF/arm-thumb-thunk-v6m.s

   1 // REQUIRES: arm
   2 // RUN: llvm-mc -arm-add-build-attributes -filetype=obj -triple=armv6m-none-eabi %s -o %t
   3 // RUN: echo "SECTIONS { \
   4 // RUN:       . = SIZEOF_HEADERS; \
   5 // RUN:       .text_low : { *(.text_low) *(.text_low2) } \
   6 // RUN:       .text_high 0x2000000 : { *(.text_high) *(.text_high2) } \
   7 // RUN:       } " > %t.script
   8 // RUN: ld.lld --no-rosegment --script %t.script %t -o %t2
   9 // RUN: llvm-objdump --no-print-imm-hex -d %t2 --triple=armv6m-none-eabi | FileCheck %s
  10 // RUN: ld.lld --no-rosegment --script %t.script %t -o %t3 --pie
  11 // RUN: llvm-objdump --no-print-imm-hex -d %t3 --triple=armv6m-none-eabi | FileCheck --check-prefix=CHECK-PI %s
  12
  13 // Range extension thunks for Arm Architecture v6m. Only Thumb instructions
  14 // are permitted which limits the access to instructions that can access the
  15 // high registers (r8 - r15), this means that the thunks have to spill
  16 // low registers (r0 - r7) in order to perform the transfer of control.
  17
  18  .syntax unified
  19  .section .text_low, "ax", %progbits
  20  .thumb
  21  .type _start, %function
  22  .balign 4
  23  .globl _start
  24 _start:
  25  bl far
  26
  27  .section .text_high, "ax", %progbits
  28  .globl far
  29  .type far, %function
  30 far:
  31  bx lr
  32
  33 // CHECK: Disassembly of section .text_low:
  34 // CHECK-EMPTY:
  35 // CHECK-NEXT: <_start>:
  36 // CHECK-NEXT:       94:        f000 f800       bl      0x98 <__Thumbv6MABSLongThunk_far>
  37 // CHECK: <__Thumbv6MABSLongThunk_far>:
  38 // CHECK-NEXT:       98:        b403    push    {r0, r1}
  39 // CHECK-NEXT:       9a:        4801    ldr     r0, [pc, #4]
  40 // CHECK-NEXT:       9c:        9001    str     r0, [sp, #4]
  41 // CHECK-NEXT:       9e:        bd01    pop     {r0, pc}
  42 // CHECK:       a0:     01 00 00 02     .word   0x02000001
  43 // CHECK: Disassembly of section .text_high:
  44 // CHECK-EMPTY:
  45 // CHECK-NEXT: <far>:
  46 // CHECK-NEXT:  2000000:        4770    bx      lr
  47
  48 // CHECK-PI: Disassembly of section .text_low:
  49 // CHECK-PI-EMPTY:
  50 // CHECK-PI-NEXT: <_start>:
  51 // CHECK-PI-NEXT:      130:     f000 f800       bl      0x134 <__Thumbv6MPILongThunk_far>
  52 // CHECK-PI: <__Thumbv6MPILongThunk_far>:
  53 // CHECK-PI-NEXT:      134:     b401    push    {r0}
  54 // CHECK-PI-NEXT:      136:     4802    ldr     r0, [pc, #8]
  55 // CHECK-PI-NEXT:      138:     4684    mov     r12, r0
  56 // CHECK-PI-NEXT:      13a:     bc01    pop     {r0}
  57 // pc = pc (0x13c + 4) + r12 (1fffec1) = 0x2000001 = .far
  58 // CHECK-PI-NEXT:      13c:     44e7    add     pc, r12
  59 // CHECK-PI-NEXT:      13e:     46c0    mov     r8, r8
  60 // CHECK-PI:           140:     c1 fe ff 01     .word   0x01fffec1
  61
  62 // CHECK-PI: Disassembly of section .text_high:
  63 // CHECK-PI-EMPTY:
  64 // CHECK-PI-NEXT: <far>:
  65 // CHECK-PI-NEXT:  2000000:     4770    bx      lr