1 /**************************************************************************** 2 * Assembly testing and benchmarking tool 3 * Copyright (c) 2015 Martin Storsjo 4 * Copyright (c) 2015 Janne Grunau 5 * 6 * This file is part of FFmpeg. 7 * 8 * FFmpeg is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 * FFmpeg is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111, USA. 21 *****************************************************************************/ 22 23 #include "libavutil/aarch64/asm.S" 24 25 const register_init, align=4 26 .quad 0x21f86d66c8ca00ce 27 .quad 0x75b6ba21077c48ad 28 .quad 0xed56bb2dcb3c7736 29 .quad 0x8bda43d3fd1a7e06 30 .quad 0xb64a9c9e5d318408 31 .quad 0xdf9a54b303f1d3a3 32 .quad 0x4a75479abd64e097 33 .quad 0x249214109d5d1c88 34 .quad 0x1a1b2550a612b48c 35 .quad 0x79445c159ce79064 36 .quad 0x2eed899d5a28ddcd 37 .quad 0x86b2536fcd8cf636 38 .quad 0xb0856806085e7943 39 .quad 0x3f2bf84fc0fcca4e 40 .quad 0xacbd382dcf5b8de2 41 .quad 0xd229e1f5b281303f 42 .quad 0x71aeaff20b095fd9 43 .quad 0xab63e2e11fa38ed9 44 endconst 45 46 47 const error_message_register 48 .asciz "failed to preserve register" 49 error_message_stack: 50 .asciz "stack clobbered" 51 endconst 52 53 54 // max number of args used by any asm function. 55 #define MAX_ARGS 15 56 57 #define CLOBBER_STACK ((8*MAX_ARGS + 15) & ~15) 58 59 function checkasm_stack_clobber, export=1 60 mov x3, sp 61 mov x2, #CLOBBER_STACK 62 1: 63 stp x0, x1, [sp, #-16]! 64 subs x2, x2, #16 65 b.gt 1b 66 mov sp, x3 67 ret 68 endfunc 69 70 // + 16 for stack canary reference 71 #define ARG_STACK ((8*(MAX_ARGS - 8) + 15) & ~15 + 16) 72 73 function checkasm_checked_call, export=1 74 stp x29, x30, [sp, #-16]! 75 mov x29, sp 76 stp x19, x20, [sp, #-16]! 77 stp x21, x22, [sp, #-16]! 78 stp x23, x24, [sp, #-16]! 79 stp x25, x26, [sp, #-16]! 80 stp x27, x28, [sp, #-16]! 81 stp d8, d9, [sp, #-16]! 82 stp d10, d11, [sp, #-16]! 83 stp d12, d13, [sp, #-16]! 84 stp d14, d15, [sp, #-16]! 85 86 movrel x9, register_init 87 ldp d8, d9, [x9], #16 88 ldp d10, d11, [x9], #16 89 ldp d12, d13, [x9], #16 90 ldp d14, d15, [x9], #16 91 ldp x19, x20, [x9], #16 92 ldp x21, x22, [x9], #16 93 ldp x23, x24, [x9], #16 94 ldp x25, x26, [x9], #16 95 ldp x27, x28, [x9], #16 96 97 sub sp, sp, #ARG_STACK 98 .equ pos, 0 99 .rept MAX_ARGS-8 100 // Skip the first 8 args, that are loaded into registers 101 ldr x9, [x29, #16 + 8*8 + pos] 102 str x9, [sp, #pos] 103 .equ pos, pos + 8 104 .endr 105 106 // Fill x8-x17 with garbage. This doesn't have to be preserved, 107 // but avoids relying on them having any particular value. 108 movrel x9, register_init 109 ldp x10, x11, [x9], #32 110 ldp x12, x13, [x9], #32 111 ldp x14, x15, [x9], #32 112 ldp x16, x17, [x9], #32 113 ldp x8, x9, [x9] 114 115 // For stack overflows, the callee is free to overwrite the parameters 116 // that were passed on the stack (if any), so we can only check after 117 // that point. First figure out how many parameters the function 118 // really took on the stack: 119 ldr w2, [x29, #16 + 8*8 + (MAX_ARGS-8)*8] 120 // Load the first non-parameter value from the stack, that should be 121 // left untouched by the function. Store a copy of it inverted, so that 122 // e.g. overwriting everything with zero would be noticed. 123 ldr x2, [sp, x2, lsl #3] 124 mvn x2, x2 125 str x2, [sp, #ARG_STACK-8] 126 127 // Load the in-register arguments 128 mov x12, x0 129 ldp x0, x1, [x29, #16] 130 ldp x2, x3, [x29, #32] 131 ldp x4, x5, [x29, #48] 132 ldp x6, x7, [x29, #64] 133 // Call the target function 134 blr x12 135 136 // Load the number of stack parameters, stack canary and its reference 137 ldr w2, [x29, #16 + 8*8 + (MAX_ARGS-8)*8] 138 ldr x2, [sp, x2, lsl #3] 139 ldr x3, [sp, #ARG_STACK-8] 140 141 add sp, sp, #ARG_STACK 142 stp x0, x1, [sp, #-16]! 143 144 mvn x3, x3 145 cmp x2, x3 146 b.ne 2f 147 148 movrel x9, register_init 149 movi v3.8h, #0 150 151 .macro check_reg_neon reg1, reg2 152 ldr q1, [x9], #16 153 uzp1 v2.2d, v\reg1\().2d, v\reg2\().2d 154 eor v1.16b, v1.16b, v2.16b 155 orr v3.16b, v3.16b, v1.16b 156 .endm 157 check_reg_neon 8, 9 158 check_reg_neon 10, 11 159 check_reg_neon 12, 13 160 check_reg_neon 14, 15 161 uqxtn v3.8b, v3.8h 162 umov x3, v3.d[0] 163 164 .macro check_reg reg1, reg2 165 ldp x0, x1, [x9], #16 166 eor x0, x0, \reg1 167 eor x1, x1, \reg2 168 orr x3, x3, x0 169 orr x3, x3, x1 170 .endm 171 check_reg x19, x20 172 check_reg x21, x22 173 check_reg x23, x24 174 check_reg x25, x26 175 check_reg x27, x28 176 177 cbz x3, 0f 178 179 movrel x0, error_message_register 180 b 1f 181 2: 182 movrel x0, error_message_stack 183 1: 184 bl X(checkasm_fail_func) 185 0: 186 ldp x0, x1, [sp], #16 187 ldp d14, d15, [sp], #16 188 ldp d12, d13, [sp], #16 189 ldp d10, d11, [sp], #16 190 ldp d8, d9, [sp], #16 191 ldp x27, x28, [sp], #16 192 ldp x25, x26, [sp], #16 193 ldp x23, x24, [sp], #16 194 ldp x21, x22, [sp], #16 195 ldp x19, x20, [sp], #16 196 ldp x29, x30, [sp], #16 197 ret 198 endfunc 199