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// REQUIRES: arm
// RUN: llvm-mc --triple=thumbv7m-none-eabi --arm-add-build-attributes -filetype=obj -o %t.o %s
// RUN: echo "SECTIONS { \
// RUN: .rodata.low 0x8012 : { *(.rodata.low) } \
// RUN: .text.low 0x8f00 : { *(.text.low) } \
// RUN: .text.neg 0x9000 : { *(.text.neg) } \
// RUN: .text.pos 0x10000 : { *(.text.pos) } \
// RUN: .text.high 0x10100 : { *(.text.high) } \
// RUN: .data_high 0x1100f : { *(.data.high) } \
// RUN: } " > %t.script
// RUN: ld.lld --script %t.script %t.o -o %t
// RUN: llvm-readobj --symbols %t | FileCheck %s --check-prefix=SYMS
// RUN: llvm-objdump --no-print-imm-hex -d --no-show-raw-insn %t | FileCheck %s
/// Test the various legal cases for the R_ARM_THM_PC12 relocation
/// Interesting things to note
/// Range is +- 4095 bytes
/// The Thumb bit for function symbols is ignored
/// The expression is S + A - Pa where Pa is AlignDown(PC, 4) so we will use
/// 2-byte nops to make some of the ldr instructions 2-byte aligned.
.section .rodata.low, "a", %progbits
dat1:
.byte 0
dat2:
.byte 1
dat3:
.byte 2
dat4:
.byte 3
.section .text.low, "ax", %progbits
.balign 4
.global target1
.type target1, %function
target1:
bx lr
.type target2, %function
target2:
bx lr
.section .text.neg, "ax", %progbits
.balign 4
.global _start
.thumb_func
_start:
nop
/// ldr r0, dat1
.inst.w 0xf85f0004
.reloc 2, R_ARM_THM_PC12, dat1
/// ldr r1, dat2
.inst.w 0xf85f1004
.reloc 6, R_ARM_THM_PC12, dat2
nop
/// ldr r2, dat3
.inst.w 0xf85f2004
.reloc 0xc, R_ARM_THM_PC12, dat3
/// ldr r3, dat4
.inst.w 0xf85f3004
.reloc 0x10, R_ARM_THM_PC12, dat4
/// ldr r0, target1
.inst.w 0xf85f0004
.reloc 0x14, R_ARM_THM_PC12, target1
nop
/// ldr r1, target2
.inst.w 0xf85f1004
.reloc 0x1a, R_ARM_THM_PC12, target2
.section .text.pos, "ax", %progbits
.balign 4
.global pos
.thumb_func
pos:
/// ldr r2, target3
.inst.w 0xf85f2004
.reloc 0, R_ARM_THM_PC12, target3
nop
/// ldr r3, target4
.inst.w 0xf85f3004
.reloc 6, R_ARM_THM_PC12, target4
nop
/// ldr r0, dat5
.inst.w 0xf85f0004
.reloc 0xc, R_ARM_THM_PC12, dat5
/// ldr r1, dat6
.inst.w 0xf85f1004
.reloc 0x10, R_ARM_THM_PC12, dat6
nop
/// ldr r2, dat7
.inst.w 0xf85f2004
.reloc 0x16, R_ARM_THM_PC12, dat7
/// ldr r3, dat8
.inst.w 0xf85f3004
.reloc 0x1a, R_ARM_THM_PC12, dat8
/// positive addend in instruction, all others are -4 (PC bias)
///ldr.w r4, dat5 + 8
.inst 0xf8df4004
.reloc 0x1e, R_ARM_THM_PC12, dat5
.section .text.high, "ax", %progbits
.balign 4
.thumb_func
.global target3
target3:
bx lr
.thumb_func
target4:
bx lr
.section .data.high, "aw", %progbits
dat5:
.byte 0
dat6:
.byte 1
dat7:
.byte 2
dat8:
.byte 3
// SYMS: Name: dat1
// SYMS-NEXT: Value: 0x8012
// SYMS: Name: dat2
// SYMS-NEXT: Value: 0x8013
// SYMS: Name: dat3
// SYMS-NEXT: Value: 0x8014
// SYMS: Name: dat4
// SYMS-NEXT: Value: 0x8015
// CHECK: 00008f00 <target1>:
// CHECK-NEXT: 8f00: bx lr
// CHECK: 00008f02 <target2>:
// CHECK-NEXT: 8f02: bx lr
// CHECK: 00009000 <_start>:
// CHECK-NEXT: 9000: nop
/// AlignDown(0x9002+4, 4) - 0xff2 = 0x8012
// CHECK-NEXT: 9002: ldr.w r0, [pc, #-4082]
/// AlignDown(0x9006+4, 4) - 0xff5 = 0x8013
// CHECK-NEXT: 9006: ldr.w r1, [pc, #-4085]
// CHECK-NEXT: 900a: nop
/// AlignDown(0x900c+4, 4) - 0xffc = 0x8014
// CHECK-NEXT: 900c: ldr.w r2, [pc, #-4092]
/// AlignDown(0x9010+4, 4) - 0xfff = 0x8015
// CHECK-NEXT: 9010: ldr.w r3, [pc, #-4095]
/// AlignDown(0x9014+4, 4) - 0x118 = 0x8f00
// CHECK-NEXT: 9014: ldr.w r0, [pc, #-280]
// CHECK-NEXT: 9018: nop
/// AlignDown(0x901a+4, 4) - 0x11a = 0x8f02
// CHECK-NEXT: 901a: ldr.w r1, [pc, #-282]
// CHECK: 00010000 <pos>:
/// AlignDown(0x10000+4, 4) + 0x1c = 0x10100
// CHECK-NEXT: 10000: ldr.w r2, [pc, #252]
// CHECK-NEXT: 10004: nop
/// AlignDown(0x10006+4, 4) + 0x1a = 0x10122
// CHECK-NEXT: 10006: ldr.w r3, [pc, #250]
// CHECK-NEXT: 1000a: nop
/// AlignDown(0x1000c+4, 4) + 0xfff = 0x1100f
// CHECK-NEXT: 1000c: ldr.w r0, [pc, #4095]
/// AlignDown(0x10010+4, 4) + 0xffc = 0x11010
// CHECK-NEXT: 10010: ldr.w r1, [pc, #4092]
// CHECK-NEXT: 10014: nop
/// AlignDown(0x10016+4, 4) + 0xff9 = 0x11011
// CHECK-NEXT: 10016: ldr.w r2, [pc, #4089]
/// AlignDown(0x1001a+4, 4) + 0xff6 = 0x11012
// CHECK-NEXT: 1001a: ldr.w r3, [pc, #4086]
/// AlignDown(0x1001e+4, 4) + 0xff7 = 0x11017 = dat5 + 8
// CHECK-NEXT: 1001e: ldr.w r4, [pc, #4087]
// CHECK: 00010100 <target3>:
// CHECK-NEXT: 10100: bx lr
// CHECK: 00010102 <target4>:
// CHECK-NEXT: 10102: bx lr
// SYMS: Name: dat5
// SYMS-NEXT: Value: 0x1100F
// SYMS: Name: dat6
// SYMS-NEXT: Value: 0x11010
// SYMS: Name: dat7
// SYMS-NEXT: Value: 0x11011
// SYMS: Name: dat8
// SYMS-NEXT: Value: 0x11012
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