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| // REQUIRES: arm
// RUN: llvm-mc -filetype=obj --arm-add-build-attributes -triple=armv7a-none-linux-gnueabi %s -o %t
// RUN: ld.lld %t --no-merge-exidx-entries -o %t2 --gc-sections
// RUN: llvm-objdump -d -triple=armv7a-none-linux-gnueabi --no-show-raw-insn %t2 | FileCheck %s
// RUN: llvm-objdump -s -triple=armv7a-none-linux-gnueabi %t2 | FileCheck -check-prefix=CHECK-EXIDX %s
// Test the behavior of .ARM.exidx sections under garbage collection
// A .ARM.exidx section is live if it has a relocation to a live executable
// section.
// A .ARM.exidx section may have a relocation to a .ARM.extab section, if the
// .ARM.exidx is live then the .ARM.extab section is live
.syntax unified
.section .text.func1, "ax",%progbits
.global func1
func1:
.fnstart
bx lr
.save {r7, lr}
.setfp r7, sp, #0
.fnend
.section .text.unusedfunc1, "ax",%progbits
.global unusedfunc1
unusedfunc1:
.fnstart
bx lr
.cantunwind
.fnend
// Unwinding instructions for .text2 too large for an inline entry ARM.exidx
// entry. A separate .ARM.extab section is created to hold the unwind entries
// The .ARM.exidx table entry has a reference to the .ARM.extab section.
.section .text.func2, "ax",%progbits
.global func2
func2:
.fnstart
bx lr
.personality __gxx_personality_v0
.handlerdata
.section .text.func2
.fnend
// An unused function with a reference to a .ARM.extab section. Both should
// be removed by gc.
.section .text.unusedfunc2, "ax",%progbits
.global unusedfunc2
unusedfunc2:
.fnstart
bx lr
.personality __gxx_personality_v1
.handlerdata
.section .text.unusedfunc2
.fnend
// Dummy implementation of personality routines to satisfy reference from
// exception tables
.section .text.__gcc_personality_v0, "ax", %progbits
.global __gxx_personality_v0
__gxx_personality_v0:
.fnstart
bx lr
.cantunwind
.fnend
.section .text.__gcc_personality_v1, "ax", %progbits
.global __gxx_personality_v1
__gxx_personality_v1:
.fnstart
bx lr
.cantunwind
.fnend
.section .text.__aeabi_unwind_cpp_pr0, "ax", %progbits
.global __aeabi_unwind_cpp_pr0
__aeabi_unwind_cpp_pr0:
.fnstart
bx lr
.cantunwind
.fnend
// Entry point for GC
.text
.global _start
_start:
bl func1
bl func2
bx lr
// GC should have only removed unusedfunc1 and unusedfunc2 the personality
// routines are kept alive by references from live .ARM.exidx and .ARM.extab
// sections
// CHECK: Disassembly of section .text:
// CHECK-EMPTY:
// CHECK-NEXT: _start:
// CHECK-NEXT: 1110c: bl #4 <func1>
// CHECK-NEXT: 11110: bl #4 <func2>
// CHECK-NEXT: 11114: bx lr
// CHECK: func1:
// CHECK-NEXT: 11118: bx lr
// CHECK: func2:
// CHECK-NEXT: 1111c: bx lr
// CHECK: __gxx_personality_v0:
// CHECK-NEXT: 11120: bx lr
// CHECK: __aeabi_unwind_cpp_pr0:
// CHECK-NEXT: 11124: bx lr
// GC should have removed table entries for unusedfunc1, unusedfunc2
// and __gxx_personality_v1
// CHECK-NOT: unusedfunc1
// CHECK-NOT: unusedfunc2
// CHECK-NOT: __gxx_personality_v1
// CHECK-EXIDX: Contents of section .ARM.exidx:
// 100d4 + 1038 = 1110c = _start
// 100dc + 103c = 11118 = func1
// CHECK-EXIDX-NEXT: 100d4 38100000 01000000 3c100000 08849780
// 100e4 + 1038 = 1111c = func2 (100e8 + 1c = 10104 = .ARM.extab)
// 100ec + 1034 = 11120 = __gxx_personality_v0
// CHECK-EXIDX-NEXT: 100e4 38100000 1c000000 34100000 01000000
// 100f4 + 1030 = 11018 = __aeabi_unwind_cpp_pr0
// 100fc + 102c = 1101c = __aeabi_unwind_cpp_pr0 + sizeof(__aeabi_unwind_cpp_pr0)
// CHECK-EXIDX-NEXT: 100f4 30100000 01000000 2c100000 01000000
// CHECK-EXIDX-NEXT: Contents of section .ARM.extab:
// 10104 + 101c = 11120 = __gxx_personality_v0
// CHECK-EXIDX-NEXT: 10104 1c100000 b0b0b000
|