1/* $NetBSD: divsi3.S,v 1.4 2003/04/05 23:27:15 bjh21 Exp $ */ 2 3/*- 4 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 5 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 6 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 7 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 8 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 9 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 10 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 11 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 12 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 13 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 14 * SUCH DAMAGE. 15 */ 16 17#include <machine/asm.h> 18__FBSDID("$FreeBSD$"); 19 20/* 21 * stack is aligned as there's a possibility of branching to L_overflow 22 * which makes a C call 23 */ 24 25ENTRY_NP(__umodsi3) 26 stmfd sp!, {lr} 27 sub sp, sp, #4 /* align stack */ 28 bl .L_udivide 29 add sp, sp, #4 /* unalign stack */ 30 mov r0, r1 31 ldmfd sp!, {pc} 32 33ENTRY_NP(__modsi3) 34 stmfd sp!, {lr} 35 sub sp, sp, #4 /* align stack */ 36 bl .L_divide 37 add sp, sp, #4 /* unalign stack */ 38 mov r0, r1 39 ldmfd sp!, {pc} 40 41.L_overflow: 42#if !defined(_KERNEL) && !defined(_STANDALONE) 43 mov r0, #8 /* SIGFPE */ 44 bl PIC_SYM(_C_LABEL(raise), PLT) /* raise it */ 45 mov r0, #0 46#else 47 /* XXX should cause a fatal error */ 48 mvn r0, #0 49#endif 50 RET 51 52#ifdef __ARM_EABI__ 53ENTRY_NP(__aeabi_uidiv) 54ENTRY_NP(__aeabi_uidivmod) 55#endif 56ENTRY_NP(__udivsi3) 57.L_udivide: /* r0 = r0 / r1; r1 = r0 % r1 */ 58 eor r0, r1, r0 59 eor r1, r0, r1 60 eor r0, r1, r0 61 /* r0 = r1 / r0; r1 = r1 % r0 */ 62 cmp r0, #1 63 bcc .L_overflow 64 beq .L_divide_l0 65 mov ip, #0 66 movs r1, r1 67 bpl .L_divide_l1 68 orr ip, ip, #0x20000000 /* ip bit 0x20000000 = -ve r1 */ 69 movs r1, r1, lsr #1 70 orrcs ip, ip, #0x10000000 /* ip bit 0x10000000 = bit 0 of r1 */ 71 b .L_divide_l1 72 73.L_divide_l0: /* r0 == 1 */ 74 mov r0, r1 75 mov r1, #0 76 RET 77 78#ifdef __ARM_EABI__ 79ENTRY_NP(__aeabi_idiv) 80ENTRY_NP(__aeabi_idivmod) 81#endif 82ENTRY_NP(__divsi3) 83.L_divide: /* r0 = r0 / r1; r1 = r0 % r1 */ 84 eor r0, r1, r0 85 eor r1, r0, r1 86 eor r0, r1, r0 87 /* r0 = r1 / r0; r1 = r1 % r0 */ 88 cmp r0, #1 89 bcc .L_overflow 90 beq .L_divide_l0 91 ands ip, r0, #0x80000000 92 rsbmi r0, r0, #0 93 ands r2, r1, #0x80000000 94 eor ip, ip, r2 95 rsbmi r1, r1, #0 96 orr ip, r2, ip, lsr #1 /* ip bit 0x40000000 = -ve division */ 97 /* ip bit 0x80000000 = -ve remainder */ 98 99.L_divide_l1: 100 mov r2, #1 101 mov r3, #0 102 103 /* 104 * If the highest bit of the dividend is set, we have to be 105 * careful when shifting the divisor. Test this. 106 */ 107 movs r1,r1 108 bpl .L_old_code 109 110 /* 111 * At this point, the highest bit of r1 is known to be set. 112 * We abuse this below in the tst instructions. 113 */ 114 tst r1, r0 /*, lsl #0 */ 115 bmi .L_divide_b1 116 tst r1, r0, lsl #1 117 bmi .L_divide_b2 118 tst r1, r0, lsl #2 119 bmi .L_divide_b3 120 tst r1, r0, lsl #3 121 bmi .L_divide_b4 122 tst r1, r0, lsl #4 123 bmi .L_divide_b5 124 tst r1, r0, lsl #5 125 bmi .L_divide_b6 126 tst r1, r0, lsl #6 127 bmi .L_divide_b7 128 tst r1, r0, lsl #7 129 bmi .L_divide_b8 130 tst r1, r0, lsl #8 131 bmi .L_divide_b9 132 tst r1, r0, lsl #9 133 bmi .L_divide_b10 134 tst r1, r0, lsl #10 135 bmi .L_divide_b11 136 tst r1, r0, lsl #11 137 bmi .L_divide_b12 138 tst r1, r0, lsl #12 139 bmi .L_divide_b13 140 tst r1, r0, lsl #13 141 bmi .L_divide_b14 142 tst r1, r0, lsl #14 143 bmi .L_divide_b15 144 tst r1, r0, lsl #15 145 bmi .L_divide_b16 146 tst r1, r0, lsl #16 147 bmi .L_divide_b17 148 tst r1, r0, lsl #17 149 bmi .L_divide_b18 150 tst r1, r0, lsl #18 151 bmi .L_divide_b19 152 tst r1, r0, lsl #19 153 bmi .L_divide_b20 154 tst r1, r0, lsl #20 155 bmi .L_divide_b21 156 tst r1, r0, lsl #21 157 bmi .L_divide_b22 158 tst r1, r0, lsl #22 159 bmi .L_divide_b23 160 tst r1, r0, lsl #23 161 bmi .L_divide_b24 162 tst r1, r0, lsl #24 163 bmi .L_divide_b25 164 tst r1, r0, lsl #25 165 bmi .L_divide_b26 166 tst r1, r0, lsl #26 167 bmi .L_divide_b27 168 tst r1, r0, lsl #27 169 bmi .L_divide_b28 170 tst r1, r0, lsl #28 171 bmi .L_divide_b29 172 tst r1, r0, lsl #29 173 bmi .L_divide_b30 174 tst r1, r0, lsl #30 175 bmi .L_divide_b31 176/* 177 * instead of: 178 * tst r1, r0, lsl #31 179 * bmi .L_divide_b32 180 */ 181 b .L_divide_b32 182 183.L_old_code: 184 cmp r1, r0 185 bcc .L_divide_b0 186 cmp r1, r0, lsl #1 187 bcc .L_divide_b1 188 cmp r1, r0, lsl #2 189 bcc .L_divide_b2 190 cmp r1, r0, lsl #3 191 bcc .L_divide_b3 192 cmp r1, r0, lsl #4 193 bcc .L_divide_b4 194 cmp r1, r0, lsl #5 195 bcc .L_divide_b5 196 cmp r1, r0, lsl #6 197 bcc .L_divide_b6 198 cmp r1, r0, lsl #7 199 bcc .L_divide_b7 200 cmp r1, r0, lsl #8 201 bcc .L_divide_b8 202 cmp r1, r0, lsl #9 203 bcc .L_divide_b9 204 cmp r1, r0, lsl #10 205 bcc .L_divide_b10 206 cmp r1, r0, lsl #11 207 bcc .L_divide_b11 208 cmp r1, r0, lsl #12 209 bcc .L_divide_b12 210 cmp r1, r0, lsl #13 211 bcc .L_divide_b13 212 cmp r1, r0, lsl #14 213 bcc .L_divide_b14 214 cmp r1, r0, lsl #15 215 bcc .L_divide_b15 216 cmp r1, r0, lsl #16 217 bcc .L_divide_b16 218 cmp r1, r0, lsl #17 219 bcc .L_divide_b17 220 cmp r1, r0, lsl #18 221 bcc .L_divide_b18 222 cmp r1, r0, lsl #19 223 bcc .L_divide_b19 224 cmp r1, r0, lsl #20 225 bcc .L_divide_b20 226 cmp r1, r0, lsl #21 227 bcc .L_divide_b21 228 cmp r1, r0, lsl #22 229 bcc .L_divide_b22 230 cmp r1, r0, lsl #23 231 bcc .L_divide_b23 232 cmp r1, r0, lsl #24 233 bcc .L_divide_b24 234 cmp r1, r0, lsl #25 235 bcc .L_divide_b25 236 cmp r1, r0, lsl #26 237 bcc .L_divide_b26 238 cmp r1, r0, lsl #27 239 bcc .L_divide_b27 240 cmp r1, r0, lsl #28 241 bcc .L_divide_b28 242 cmp r1, r0, lsl #29 243 bcc .L_divide_b29 244 cmp r1, r0, lsl #30 245 bcc .L_divide_b30 246.L_divide_b32: 247 cmp r1, r0, lsl #31 248 subhs r1, r1,r0, lsl #31 249 addhs r3, r3,r2, lsl #31 250.L_divide_b31: 251 cmp r1, r0, lsl #30 252 subhs r1, r1,r0, lsl #30 253 addhs r3, r3,r2, lsl #30 254.L_divide_b30: 255 cmp r1, r0, lsl #29 256 subhs r1, r1,r0, lsl #29 257 addhs r3, r3,r2, lsl #29 258.L_divide_b29: 259 cmp r1, r0, lsl #28 260 subhs r1, r1,r0, lsl #28 261 addhs r3, r3,r2, lsl #28 262.L_divide_b28: 263 cmp r1, r0, lsl #27 264 subhs r1, r1,r0, lsl #27 265 addhs r3, r3,r2, lsl #27 266.L_divide_b27: 267 cmp r1, r0, lsl #26 268 subhs r1, r1,r0, lsl #26 269 addhs r3, r3,r2, lsl #26 270.L_divide_b26: 271 cmp r1, r0, lsl #25 272 subhs r1, r1,r0, lsl #25 273 addhs r3, r3,r2, lsl #25 274.L_divide_b25: 275 cmp r1, r0, lsl #24 276 subhs r1, r1,r0, lsl #24 277 addhs r3, r3,r2, lsl #24 278.L_divide_b24: 279 cmp r1, r0, lsl #23 280 subhs r1, r1,r0, lsl #23 281 addhs r3, r3,r2, lsl #23 282.L_divide_b23: 283 cmp r1, r0, lsl #22 284 subhs r1, r1,r0, lsl #22 285 addhs r3, r3,r2, lsl #22 286.L_divide_b22: 287 cmp r1, r0, lsl #21 288 subhs r1, r1,r0, lsl #21 289 addhs r3, r3,r2, lsl #21 290.L_divide_b21: 291 cmp r1, r0, lsl #20 292 subhs r1, r1,r0, lsl #20 293 addhs r3, r3,r2, lsl #20 294.L_divide_b20: 295 cmp r1, r0, lsl #19 296 subhs r1, r1,r0, lsl #19 297 addhs r3, r3,r2, lsl #19 298.L_divide_b19: 299 cmp r1, r0, lsl #18 300 subhs r1, r1,r0, lsl #18 301 addhs r3, r3,r2, lsl #18 302.L_divide_b18: 303 cmp r1, r0, lsl #17 304 subhs r1, r1,r0, lsl #17 305 addhs r3, r3,r2, lsl #17 306.L_divide_b17: 307 cmp r1, r0, lsl #16 308 subhs r1, r1,r0, lsl #16 309 addhs r3, r3,r2, lsl #16 310.L_divide_b16: 311 cmp r1, r0, lsl #15 312 subhs r1, r1,r0, lsl #15 313 addhs r3, r3,r2, lsl #15 314.L_divide_b15: 315 cmp r1, r0, lsl #14 316 subhs r1, r1,r0, lsl #14 317 addhs r3, r3,r2, lsl #14 318.L_divide_b14: 319 cmp r1, r0, lsl #13 320 subhs r1, r1,r0, lsl #13 321 addhs r3, r3,r2, lsl #13 322.L_divide_b13: 323 cmp r1, r0, lsl #12 324 subhs r1, r1,r0, lsl #12 325 addhs r3, r3,r2, lsl #12 326.L_divide_b12: 327 cmp r1, r0, lsl #11 328 subhs r1, r1,r0, lsl #11 329 addhs r3, r3,r2, lsl #11 330.L_divide_b11: 331 cmp r1, r0, lsl #10 332 subhs r1, r1,r0, lsl #10 333 addhs r3, r3,r2, lsl #10 334.L_divide_b10: 335 cmp r1, r0, lsl #9 336 subhs r1, r1,r0, lsl #9 337 addhs r3, r3,r2, lsl #9 338.L_divide_b9: 339 cmp r1, r0, lsl #8 340 subhs r1, r1,r0, lsl #8 341 addhs r3, r3,r2, lsl #8 342.L_divide_b8: 343 cmp r1, r0, lsl #7 344 subhs r1, r1,r0, lsl #7 345 addhs r3, r3,r2, lsl #7 346.L_divide_b7: 347 cmp r1, r0, lsl #6 348 subhs r1, r1,r0, lsl #6 349 addhs r3, r3,r2, lsl #6 350.L_divide_b6: 351 cmp r1, r0, lsl #5 352 subhs r1, r1,r0, lsl #5 353 addhs r3, r3,r2, lsl #5 354.L_divide_b5: 355 cmp r1, r0, lsl #4 356 subhs r1, r1,r0, lsl #4 357 addhs r3, r3,r2, lsl #4 358.L_divide_b4: 359 cmp r1, r0, lsl #3 360 subhs r1, r1,r0, lsl #3 361 addhs r3, r3,r2, lsl #3 362.L_divide_b3: 363 cmp r1, r0, lsl #2 364 subhs r1, r1,r0, lsl #2 365 addhs r3, r3,r2, lsl #2 366.L_divide_b2: 367 cmp r1, r0, lsl #1 368 subhs r1, r1,r0, lsl #1 369 addhs r3, r3,r2, lsl #1 370.L_divide_b1: 371 cmp r1, r0 372 subhs r1, r1, r0 373 addhs r3, r3, r2 374.L_divide_b0: 375 376 tst ip, #0x20000000 377 bne .L_udivide_l1 378 mov r0, r3 379 cmp ip, #0 380 rsbmi r1, r1, #0 381 movs ip, ip, lsl #1 382 bicmi r0, r0, #0x80000000 /* Fix incase we divided 0x80000000 */ 383 rsbmi r0, r0, #0 384 RET 385 386.L_udivide_l1: 387 tst ip, #0x10000000 388 mov r1, r1, lsl #1 389 orrne r1, r1, #1 390 mov r3, r3, lsl #1 391 cmp r1, r0 392 subhs r1, r1, r0 393 addhs r3, r3, r2 394 mov r0, r3 395 RET 396