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| // REQUIRES: arm
// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %s -o %t
// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %S/Inputs/arm-exidx-cantunwind.s -o %tcantunwind
// RUN: ld.lld --no-merge-exidx-entries %t %tcantunwind -o %t2
// 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
// RUN: llvm-readobj --program-headers --sections %t2 | FileCheck -check-prefix=CHECK-PT %s
// Use Linker script to place .ARM.exidx in between .text and orphan sections
// RUN: echo "SECTIONS { \
// RUN: .text 0x11000 : { *(.text*) } \
// RUN: .ARM.exidx : { *(.ARM.exidx) } } " > %t.script
// RUN: ld.lld --no-merge-exidx-entries --script %t.script %tcantunwind %t -o %t3
// RUN: llvm-objdump -d -triple=armv7a-none-linux-gnueabi %t3 | FileCheck -check-prefix=CHECK-SCRIPT %s
// RUN: llvm-objdump -s -triple=armv7a-none-linux-gnueabi %t3 | FileCheck -check-prefix=CHECK-SCRIPT-EXIDX %s
// Each assembler created .ARM.exidx section has the SHF_LINK_ORDER flag set
// with the sh_link containing the section index of the executable section
// containing the function it describes. The linker must combine the .ARM.exidx
// InputSections in the same order that it has combined the executable section,
// such that the combined .ARM.exidx OutputSection can be used as a binary
// search table.
.syntax unified
.section .text, "ax",%progbits
.globl _start
_start:
.fnstart
bx lr
.cantunwind
.fnend
.section .text.f1, "ax", %progbits
.globl f1
f1:
.fnstart
bx lr
.cantunwind
.fnend
.section .text.f2, "ax", %progbits
.globl f2
f2:
.fnstart
bx lr
.cantunwind
.fnend
.globl f3
f3:
.fnstart
bx lr
.cantunwind
.fnend
// Check default no linker script order.
// CHECK: Disassembly of section .text:
// CHECK-EMPTY:
// CHECK: _start:
// CHECK-NEXT: 11124: bx lr
// CHECK: f1:
// CHECK-NEXT: 11128: bx lr
// CHECK: f2:
// CHECK-NEXT: 1112c: bx lr
// CHECK: f3:
// CHECK-NEXT: 11130: bx lr
// CHECK: func4:
// CHECK-NEXT: 11134: bx lr
// CHECK: func5:
// CHECK-NEXT: 11138: bx lr
// CHECK: Disassembly of section .func1:
// CHECK-EMPTY:
// CHECK-NEXT: func1:
// CHECK-NEXT: 1113c: bx lr
// CHECK: Disassembly of section .func2:
// CHECK-EMPTY:
// CHECK-NEXT: func2:
// CHECK-NEXT: 11140: bx lr
// CHECK: Disassembly of section .func3:
// CHECK-EMPTY:
// CHECK-NEXT: func3:
// CHECK-NEXT: 11144: bx lr
// Each .ARM.exidx section has two 4 byte fields
// Field 1 is the 31-bit offset to the function. The top bit is used to
// indicate whether Field 2 is a pointer or an inline table entry.
// Field 2 is either a pointer to a .ARM.extab section or an inline table
// In this example all Field 2 entries are inline can't unwind (0x1)
// We expect to see the entries in the same order as the functions
// CHECK-EXIDX: Contents of section .ARM.exidx:
// 100d4 + 1050 = 11124 = _start
// 100dc + 104c = 11128 = f1
// CHECK-EXIDX-NEXT: 100d4 50100000 01000000 4c100000 01000000
// 100e4 + 1048 = 1112c = f2
// 100ec + 1044 = 11130 = f3
// CHECK-EXIDX-NEXT: 100e4 48100000 01000000 44100000 01000000
// 100f4 + 1040 = 11134 = func4
// 100fc + 103c = 11138 = func5
// CHECK-EXIDX-NEXT: 100f4 40100000 01000000 3c100000 01000000
// 10104 + 1038 = 1113c = func1
// 1010c + 1034 = 11140 = func2
// CHECK-EXIDX-NEXT: 10104 38100000 01000000 34100000 01000000
// 10114 + 1030 = 11144 = func3
// CHECK-EXIDX-NEXT: 10114 30100000 01000000
// Check that PT_ARM_EXIDX program header has been generated that describes
// the .ARM.exidx output section
// CHECK-PT: Name: .ARM.exidx
// CHECK-PT-NEXT: Type: SHT_ARM_EXIDX (0x70000001)
// CHECK-PT-NEXT: Flags [
// CHECK-PT-NEXT: SHF_ALLOC
// CHECK-PT-NEXT: SHF_LINK_ORDER
// CHECK-PT-NEXT: ]
// CHECK-PT-NEXT: Address: 0x100D4
// CHECK-PT-NEXT: Offset: 0xD4
// CHECK-PT-NEXT: Size: 80
// CHECK-PT: Type: PT_ARM_EXIDX (0x70000001)
// CHECK-PT-NEXT: Offset: 0xD4
// CHECK-PT-NEXT: VirtualAddress: 0x100D4
// CHECK-PT-NEXT: PhysicalAddress: 0x100D4
// CHECK-PT-NEXT: FileSize: 80
// CHECK-PT-NEXT: MemSize: 80
// CHECK-PT-NEXT: Flags [ (0x4)
// CHECK-PT-NEXT: PF_R (0x4)
// CHECK-PT-NEXT: ]
// CHECK-PT-NEXT: Alignment: 4
// CHECK-PT-NEXT: }
// Check linker script order. The .ARM.exidx section will be inserted after
// the .text section but before the orphan sections
// CHECK-SCRIPT: Disassembly of section .text:
// CHECK-SCRIPT-EMPTY:
// CHECK-SCRIPT-NEXT: func4:
// CHECK-SCRIPT-NEXT: 11000: 1e ff 2f e1 bx lr
// CHECK-SCRIPT: func5:
// CHECK-SCRIPT-NEXT: 11004: 1e ff 2f e1 bx lr
// CHECK-SCRIPT: _start:
// CHECK-SCRIPT-NEXT: 11008: 1e ff 2f e1 bx lr
// CHECK-SCRIPT: f1:
// CHECK-SCRIPT-NEXT: 1100c: 1e ff 2f e1 bx lr
// CHECK-SCRIPT: f2:
// CHECK-SCRIPT-NEXT: 11010: 1e ff 2f e1 bx lr
// CHECK-SCRIPT: f3:
// CHECK-SCRIPT-NEXT: 11014: 1e ff 2f e1 bx lr
// CHECK-SCRIPT-EMPTY:
// CHECK-SCRIPT-NEXT: Disassembly of section .func1:
// CHECK-SCRIPT-EMPTY:
// CHECK-SCRIPT-NEXT: func1:
// CHECK-SCRIPT-NEXT: 11018: 1e ff 2f e1 bx lr
// CHECK-SCRIPT-EMPTY:
// CHECK-SCRIPT-NEXT: Disassembly of section .func2:
// CHECK-SCRIPT-EMPTY:
// CHECK-SCRIPT-NEXT: func2:
// CHECK-SCRIPT-NEXT: 1101c: 1e ff 2f e1 bx lr
// CHECK-SCRIPT-EMPTY:
// CHECK-SCRIPT-NEXT: Disassembly of section .func3:
// CHECK-SCRIPT-EMPTY:
// CHECK-SCRIPT-NEXT: func3:
// CHECK-SCRIPT-NEXT: 11020: 1e ff 2f e1 bx lr
// Check that the .ARM.exidx section is sorted in order as the functions
// The offset in field 1, is 32-bit so in the binary the most significant bit
// 11024 - 24 = 11000 func4
// 1102c - 28 = 11004 func5
// CHECK-SCRIPT-EXIDX: 11024 dcffff7f 01000000 d8ffff7f 01000000
// 11034 - 2c = 11008 _start
// 1103c - 30 = 1100c f1
// CHECK-SCRIPT-EXIDX-NEXT: 11034 d4ffff7f 01000000 d0ffff7f 01000000
// 11044 - 34 = 11010 f2
// 1104c - 38 = 11014 f3
// CHECK-SCRIPT-EXIDX-NEXT: 11044 ccffff7f 01000000 c8ffff7f 01000000
// 11054 - 3c = 11018 func1
// 1105c - 40 = 1101c func2
// CHECK-SCRIPT-EXIDX-NEXT: 11054 c4ffff7f 01000000 c0ffff7f 01000000
// 11064 - 44 = 11020 func3
// 11068 - 48 = 11024 func3 + sizeof(func3)
// CHECK-SCRIPT-EXIDX-NEXT: 11064 bcffff7f 01000000 b8ffff7f 01000000
|