bolt/test/X86/false-jump-table.s

   1 ## Check that jump table detection does not fail on a false
   2 ## reference to a jump table.
   3
   4 # REQUIRES: system-linux
   5
   6 # RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown \
   7 # RUN:   %s -o %t.o
   8 # RUN: %clang %cflags %t.o -o %t.exe -Wl,-q
   9
  10 # RUN: llvm-bolt %t.exe --print-cfg \
  11 # RUN:    --print-only=inc_dup -o %t.out | FileCheck %s
  12
  13         .file   "jump_table.c"
  14         .section        .rodata
  15 .LC0:
  16         .string "0"
  17 .LC1:
  18         .string "1"
  19 .LC2:
  20         .string "2"
  21 .LC3:
  22         .string "3"
  23 .LC4:
  24         .string "4"
  25 .LC5:
  26         .string "5"
  27         .text
  28         .globl  inc_dup
  29         .type   inc_dup, @function
  30 inc_dup:
  31 .LFB0:
  32         .cfi_startproc
  33         pushq   %rbp
  34         .cfi_def_cfa_offset 16
  35         .cfi_offset 6, -16
  36         movq    %rsp, %rbp
  37         .cfi_def_cfa_register 6
  38         subq    $16, %rsp
  39         movl    %edi, -4(%rbp)
  40         movl    -4(%rbp), %eax
  41         subl    $10, %eax
  42         cmpl    $5, %eax
  43         ja      .L2
  44 # Control flow confusing for JT detection
  45 # CHECK: leaq    "JUMP_TABLE{{.*}}"(%rip), %rdx
  46         leaq    .L4(%rip), %rdx
  47   jmp .LJT
  48 # CHECK: leaq    {{.*}}(%rip), %rdx
  49         leaq    .LC0(%rip), %rdx
  50   jmp .L10
  51 .LJT:
  52   movslq  (%rdx,%rax,4), %rax
  53         addq    %rdx, %rax
  54 # CHECK: jmpq    *%rax # UNKNOWN CONTROL FLOW
  55         jmp     *%rax
  56         .section        .rodata
  57         .align 4
  58         .align 4
  59 .L4:
  60         .long   .L3-.L4
  61         .long   .L5-.L4
  62         .long   .L6-.L4
  63         .long   .L7-.L4
  64         .long   .L8-.L4
  65         .long   .L9-.L4
  66         .text
  67 .L3:
  68         leaq    .LC0(%rip), %rdi
  69         call    puts@PLT
  70         movl    $1, %eax
  71         jmp     .L10
  72 .L5:
  73         leaq    .LC1(%rip), %rdi
  74         call    puts@PLT
  75         movl    $2, %eax
  76         jmp     .L10
  77 .L6:
  78         leaq    .LC2(%rip), %rdi
  79         call    puts@PLT
  80         movl    $3, %eax
  81         jmp     .L10
  82 .L7:
  83         leaq    .LC3(%rip), %rdi
  84         call    puts@PLT
  85         movl    $4, %eax
  86         jmp     .L10
  87 .L8:
  88         leaq    .LC4(%rip), %rdi
  89         call    puts@PLT
  90         movl    $5, %eax
  91         jmp     .L10
  92 .L9:
  93         leaq    .LC5(%rip), %rdi
  94         call    puts@PLT
  95         movl    $6, %eax
  96         jmp     .L10
  97 .L2:
  98         movl    -4(%rbp), %eax
  99         addl    $1, %eax
 100 .L10:
 101         leave
 102         .cfi_def_cfa 7, 8
 103         ret
 104         .cfi_endproc
 105 .LFE0:
 106         .size   inc_dup, .-inc_dup
 107         .text
 108         .globl  main
 109         .type   main, @function
 110 main:
 111 .LFB1:
 112         .cfi_startproc
 113         pushq   %rbp
 114         .cfi_def_cfa_offset 16
 115         .cfi_offset 6, -16
 116         movq    %rsp, %rbp
 117         .cfi_def_cfa_register 6
 118         subq    $16, %rsp
 119         movl    %edi, -4(%rbp)
 120         movq    %rsi, -16(%rbp)
 121         movl    -4(%rbp), %eax
 122         addl    $9, %eax
 123         movl    %eax, %edi
 124         call    inc_dup@PLT
 125         leave
 126         .cfi_def_cfa 7, 8
 127         ret
 128         .cfi_endproc
 129 .LFE1:
 130         .size   main, .-main
 131         .ident  "GCC: (GNU) 6.3.0"
 132         .section        .note.GNU-stack,"",@progbits