arm-fix-cortex-a8-blx.s
1.14 KB
// REQUIRES: arm
// RUN: llvm-mc -filetype=obj -triple=armv7a-linux-gnueabihf --arm-add-build-attributes %s -o %t.o
// RUN: ld.lld --fix-cortex-a8 -verbose %t.o -o %t2 2>&1 | FileCheck %s
// RUN: llvm-objdump -d --no-show-raw-insn --start-address=0x21ffa --stop-address=0x22008 %t2 | FileCheck --check-prefix=CHECK-PATCH %s
/// Test that the patch can work on an unrelocated BLX. Neither clang or GCC
/// will emit these without a relocation, but they could be produced by ELF
/// processing tools.
// CHECK: ld.lld: detected cortex-a8-657419 erratum sequence starting at 21FFE in unpatched output.
.syntax unified
.text
.type _start, %function
.balign 4096
.global _start
.arm
_start:
bx lr
.space 4086
.thumb
/// 32-bit Branch link and exchange spans 2 4KiB regions, preceded by a
/// 32-bit non branch instruction. Expect a patch.
nop.w
/// Encoding for blx _start. Use .inst.n directives to avoid a relocation.
.inst.n 0xf7ff
.inst.n 0xe800
// CHECK-PATCH: 21ffa: nop.w
// CHECK-PATCH-NEXT: 21ffe: blx #4
// CHECK-PATCH: 00022004 <__CortexA8657417_21FFE>:
// CHECK-PATCH-NEXT: 22004: b #-4104