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// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %s -o %t
// RUN: ld.lld %t -o %t2 --gc-sections 2>&1
// RUN: llvm-objdump -d -triple=armv7a-none-linux-gnueabi %t2 | FileCheck %s
// RUN: llvm-objdump -s -triple=armv7a-none-linux-gnueabi %t2 | FileCheck -check-prefix=CHECK-EXIDX %s
// REQUIRES: arm
// 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-NEXT: _start:
// CHECK-NEXT: 11000: 01 00 00 eb bl #4 <func1>
// CHECK-NEXT: 11004: 01 00 00 eb bl #4 <func2>
// CHECK-NEXT: 11008: 1e ff 2f e1 bx lr
// CHECK: func1:
// CHECK-NEXT: 1100c: 1e ff 2f e1 bx lr
// CHECK: func2:
// CHECK-NEXT: 11010: 1e ff 2f e1 bx lr
// CHECK: __gxx_personality_v0:
// CHECK-NEXT: 11014: 1e ff 2f e1 bx lr
// CHECK: __aeabi_unwind_cpp_pr0:
// CHECK-NEXT: 11018: 1e ff 2f e1 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 + f38 = 1100c = func1
// 100dc + f34 = 11010 = func2 (100e0 + 1c = 100fc = .ARM.extab)
// CHECK-EXIDX-NEXT: 100d4 380f0000 08849780 340f0000 1c000000
// 100e4 + f30 = 11014 = __gxx_personality_v0
// 100ec + f2c = 11018 = __aeabi_unwind_cpp_pr0
// CHECK-EXIDX-NEXT: 100e4 300f0000 01000000 2c0f0000 01000000
// 100f4 + f28 = 1101c = __aeabi_unwind_cpp_pr0 + sizeof(__aeabi_unwind_cpp_pr0)
// CHECK-EXIDX-NEXT: 100f4 280f0000 01000000
// CHECK-EXIDX-NEXT: Contents of section .ARM.extab:
// 100fc + f18 = 11014 = __gxx_personality_v0
// CHECK-EXIDX-NEXT: 100fc 180f0000 b0b0b000
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