// REQUIRES: arm
// RUN: llvm-mc -arm-add-build-attributes -filetype=obj -triple=armv6m-none-eabi %s -o %t
// RUN: echo "SECTIONS { \
// RUN: . = SIZEOF_HEADERS; \
// RUN: .text_low : { *(.text_low) *(.text_low2) } \
// RUN: .text_high 0x2000000 : { *(.text_high) *(.text_high2) } \
// RUN: } " > %t.script
// RUN: ld.lld --no-rosegment --script %t.script %t -o %t2
// RUN: llvm-objdump --no-print-imm-hex -d %t2 --triple=armv6m-none-eabi | FileCheck %s
// RUN: ld.lld --no-rosegment --script %t.script %t -o %t3 --pie
// RUN: llvm-objdump --no-print-imm-hex -d %t3 --triple=armv6m-none-eabi | FileCheck --check-prefix=CHECK-PI %s
// Range extension thunks for Arm Architecture v6m. Only Thumb instructions
// are permitted which limits the access to instructions that can access the
// high registers (r8 - r15), this means that the thunks have to spill
// low registers (r0 - r7) in order to perform the transfer of control.
.syntax unified
.section .text_low, "ax", %progbits
.thumb
.type _start, %function
.balign 4
.globl _start
_start:
bl far
.section .text_high, "ax", %progbits
.globl far
.type far, %function
far:
bx lr
// CHECK: Disassembly of section .text_low:
// CHECK-EMPTY:
// CHECK-NEXT: <_start>:
// CHECK-NEXT: 94: f000 f800 bl 0x98 <__Thumbv6MABSLongThunk_far>
// CHECK: <__Thumbv6MABSLongThunk_far>:
// CHECK-NEXT: 98: b403 push {r0, r1}
// CHECK-NEXT: 9a: 4801 ldr r0, [pc, #4]
// CHECK-NEXT: 9c: 9001 str r0, [sp, #4]
// CHECK-NEXT: 9e: bd01 pop {r0, pc}
// CHECK: a0: 01 00 00 02 .word 0x02000001
// CHECK: Disassembly of section .text_high:
// CHECK-EMPTY:
// CHECK-NEXT: <far>:
// CHECK-NEXT: 2000000: 4770 bx lr
// CHECK-PI: Disassembly of section .text_low:
// CHECK-PI-EMPTY:
// CHECK-PI-NEXT: <_start>:
// CHECK-PI-NEXT: 130: f000 f800 bl 0x134 <__Thumbv6MPILongThunk_far>
// CHECK-PI: <__Thumbv6MPILongThunk_far>:
// CHECK-PI-NEXT: 134: b401 push {r0}
// CHECK-PI-NEXT: 136: 4802 ldr r0, [pc, #8]
// CHECK-PI-NEXT: 138: 4684 mov r12, r0
// CHECK-PI-NEXT: 13a: bc01 pop {r0}
// pc = pc (0x13c + 4) + r12 (1fffec1) = 0x2000001 = .far
// CHECK-PI-NEXT: 13c: 44e7 add pc, r12
// CHECK-PI-NEXT: 13e: 46c0 mov r8, r8
// CHECK-PI: 140: c1 fe ff 01 .word 0x01fffec1
// CHECK-PI: Disassembly of section .text_high:
// CHECK-PI-EMPTY:
// CHECK-PI-NEXT: <far>:
// CHECK-PI-NEXT: 2000000: 4770 bx lr
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