_zombie: file format elf32-littlearm Disassembly of section .text: 00000000
: #include "stat.h" #include "user.h" int main(void) { 0: e92d4800 push {fp, lr} 4: e28db004 add fp, sp, #4 if(fork() > 0){ 8: eb0000a8 bl 2b0 c: e3500000 cmp r0, #0 10: da000005 ble 2c sleep(5); // Let child exit before parent. 14: e3a00005 mov r0, #5 18: eb00019b bl 68c printf(2, "Parent exits!\n"); 1c: e3a00002 mov r0, #2 20: e59f1014 ldr r1, [pc, #20] ; 3c 24: eb000201 bl 830 exit(); 28: eb0000ad bl 2e4 } printf(2, "Child exits!\n"); 2c: e3a00002 mov r0, #2 30: e59f1008 ldr r1, [pc, #8] ; 40 34: eb0001fd bl 830 exit(); 38: eb0000a9 bl 2e4 3c: 00000b18 .word 0x00000b18 40: 00000b28 .word 0x00000b28 00000044 : #include "user.h" #include "arm.h" char* strcpy(char *s, char *t) { 44: e52db004 push {fp} ; (str fp, [sp, #-4]!) char *os; os = s; while((*s++ = *t++) != 0) 48: e1a02000 mov r2, r0 #include "user.h" #include "arm.h" char* strcpy(char *s, char *t) { 4c: e28db000 add fp, sp, #0 char *os; os = s; while((*s++ = *t++) != 0) 50: e4d13001 ldrb r3, [r1], #1 54: e3530000 cmp r3, #0 58: e4c23001 strb r3, [r2], #1 5c: 1afffffb bne 50 ; return os; } 60: e28bd000 add sp, fp, #0 64: e8bd0800 pop {fp} 68: e12fff1e bx lr 0000006c : int strcmp(const char *p, const char *q) { 6c: e52db004 push {fp} ; (str fp, [sp, #-4]!) 70: e28db000 add fp, sp, #0 while(*p && *p == *q) 74: e5d03000 ldrb r3, [r0] 78: e5d12000 ldrb r2, [r1] 7c: e3530000 cmp r3, #0 80: 1a000004 bne 98 84: ea000005 b a0 88: e5f03001 ldrb r3, [r0, #1]! 8c: e3530000 cmp r3, #0 90: 0a000006 beq b0 94: e5f12001 ldrb r2, [r1, #1]! 98: e1530002 cmp r3, r2 9c: 0afffff9 beq 88 p++, q++; return (uchar)*p - (uchar)*q; } a0: e0620003 rsb r0, r2, r3 a4: e28bd000 add sp, fp, #0 a8: e8bd0800 pop {fp} ac: e12fff1e bx lr } int strcmp(const char *p, const char *q) { while(*p && *p == *q) b0: e5d12001 ldrb r2, [r1, #1] b4: eafffff9 b a0 000000b8 : return (uchar)*p - (uchar)*q; } uint strlen(char *s) { b8: e52db004 push {fp} ; (str fp, [sp, #-4]!) bc: e28db000 add fp, sp, #0 int n; for(n = 0; s[n]; n++) c0: e5d03000 ldrb r3, [r0] c4: e3530000 cmp r3, #0 c8: 01a00003 moveq r0, r3 cc: 0a000006 beq ec d0: e1a02000 mov r2, r0 d4: e3a03000 mov r3, #0 d8: e5f21001 ldrb r1, [r2, #1]! dc: e2833001 add r3, r3, #1 e0: e1a00003 mov r0, r3 e4: e3510000 cmp r1, #0 e8: 1afffffa bne d8 ; return n; } ec: e28bd000 add sp, fp, #0 f0: e8bd0800 pop {fp} f4: e12fff1e bx lr 000000f8 : memset(void *dst, int c, uint n) { char *p=dst; u32 rc=n; while (rc-- > 0) *p++ = c; f8: e3520000 cmp r2, #0 return n; } void* memset(void *dst, int c, uint n) { fc: e52db004 push {fp} ; (str fp, [sp, #-4]!) 100: e28db000 add fp, sp, #0 char *p=dst; u32 rc=n; while (rc-- > 0) *p++ = c; 104: 0a000006 beq 124 108: e6ef1071 uxtb r1, r1 10c: e1a03002 mov r3, r2 } void* memset(void *dst, int c, uint n) { char *p=dst; 110: e1a0c000 mov ip, r0 u32 rc=n; while (rc-- > 0) *p++ = c; 114: e2533001 subs r3, r3, #1 118: e4cc1001 strb r1, [ip], #1 11c: 1afffffc bne 114 120: e0800002 add r0, r0, r2 return (void *)p; } 124: e28bd000 add sp, fp, #0 128: e8bd0800 pop {fp} 12c: e12fff1e bx lr 00000130 : char* strchr(const char *s, char c) { 130: e52db004 push {fp} ; (str fp, [sp, #-4]!) 134: e28db000 add fp, sp, #0 for(; *s; s++) 138: e5d03000 ldrb r3, [r0] 13c: e3530000 cmp r3, #0 140: 1a000004 bne 158 144: ea000008 b 16c 148: e5d03001 ldrb r3, [r0, #1] 14c: e2800001 add r0, r0, #1 150: e3530000 cmp r3, #0 154: 0a000004 beq 16c if(*s == c) 158: e1530001 cmp r3, r1 15c: 1afffff9 bne 148 return (char*)s; return 0; } 160: e28bd000 add sp, fp, #0 164: e8bd0800 pop {fp} 168: e12fff1e bx lr strchr(const char *s, char c) { for(; *s; s++) if(*s == c) return (char*)s; return 0; 16c: e1a00003 mov r0, r3 170: eafffffa b 160 00000174 : } char* gets(char *buf, int max) { 174: e92d49f0 push {r4, r5, r6, r7, r8, fp, lr} 178: e28db018 add fp, sp, #24 17c: e24dd00c sub sp, sp, #12 180: e1a08000 mov r8, r0 184: e1a07001 mov r7, r1 int i, cc; char c; for(i=0; i+1 < max; ){ 188: e1a06000 mov r6, r0 18c: e3a05000 mov r5, #0 190: ea000008 b 1b8 cc = read(0, &c, 1); 194: eb000079 bl 380 if(cc < 1) 198: e3500000 cmp r0, #0 19c: da00000b ble 1d0 break; buf[i++] = c; 1a0: e55b301d ldrb r3, [fp, #-29] if(c == '\n' || c == '\r') 1a4: e1a05004 mov r5, r4 1a8: e353000a cmp r3, #10 1ac: 1353000d cmpne r3, #13 for(i=0; i+1 < max; ){ cc = read(0, &c, 1); if(cc < 1) break; buf[i++] = c; 1b0: e4c63001 strb r3, [r6], #1 if(c == '\n' || c == '\r') 1b4: 0a00000a beq 1e4 { int i, cc; char c; for(i=0; i+1 < max; ){ cc = read(0, &c, 1); 1b8: e3a02001 mov r2, #1 gets(char *buf, int max) { int i, cc; char c; for(i=0; i+1 < max; ){ 1bc: e0854002 add r4, r5, r2 1c0: e1540007 cmp r4, r7 cc = read(0, &c, 1); 1c4: e3a00000 mov r0, #0 1c8: e24b101d sub r1, fp, #29 gets(char *buf, int max) { int i, cc; char c; for(i=0; i+1 < max; ){ 1cc: bafffff0 blt 194 break; buf[i++] = c; if(c == '\n' || c == '\r') break; } buf[i] = '\0'; 1d0: e3a03000 mov r3, #0 1d4: e7c83005 strb r3, [r8, r5] return buf; } 1d8: e1a00008 mov r0, r8 1dc: e24bd018 sub sp, fp, #24 1e0: e8bd89f0 pop {r4, r5, r6, r7, r8, fp, pc} gets(char *buf, int max) { int i, cc; char c; for(i=0; i+1 < max; ){ 1e4: e1a05004 mov r5, r4 1e8: eafffff8 b 1d0 000001ec : return buf; } int stat(char *n, struct stat *st) { 1ec: e92d4830 push {r4, r5, fp, lr} 1f0: e1a05001 mov r5, r1 1f4: e28db00c add fp, sp, #12 int fd; int r; fd = open(n, O_RDONLY); 1f8: e3a01000 mov r1, #0 1fc: eb0000a0 bl 484 if(fd < 0) 200: e2504000 subs r4, r0, #0 return -1; 204: b3e05000 mvnlt r5, #0 { int fd; int r; fd = open(n, O_RDONLY); if(fd < 0) 208: ba000004 blt 220 return -1; r = fstat(fd, st); 20c: e1a01005 mov r1, r5 210: eb0000c2 bl 520 214: e1a05000 mov r5, r0 close(fd); 218: e1a00004 mov r0, r4 21c: eb000071 bl 3e8 return r; } 220: e1a00005 mov r0, r5 224: e8bd8830 pop {r4, r5, fp, pc} 00000228 : int atoi(const char *s) { 228: e52db004 push {fp} ; (str fp, [sp, #-4]!) 22c: e28db000 add fp, sp, #0 int n; n = 0; while('0' <= *s && *s <= '9') 230: e5d03000 ldrb r3, [r0] 234: e2432030 sub r2, r3, #48 ; 0x30 238: e6ef2072 uxtb r2, r2 23c: e3520009 cmp r2, #9 int atoi(const char *s) { int n; n = 0; 240: 83a00000 movhi r0, #0 while('0' <= *s && *s <= '9') 244: 8a000009 bhi 270 248: e1a02000 mov r2, r0 int atoi(const char *s) { int n; n = 0; 24c: e3a00000 mov r0, #0 while('0' <= *s && *s <= '9') n = n*10 + *s++ - '0'; 250: e0800100 add r0, r0, r0, lsl #2 254: e0830080 add r0, r3, r0, lsl #1 atoi(const char *s) { int n; n = 0; while('0' <= *s && *s <= '9') 258: e5f23001 ldrb r3, [r2, #1]! n = n*10 + *s++ - '0'; 25c: e2400030 sub r0, r0, #48 ; 0x30 atoi(const char *s) { int n; n = 0; while('0' <= *s && *s <= '9') 260: e2431030 sub r1, r3, #48 ; 0x30 264: e6ef1071 uxtb r1, r1 268: e3510009 cmp r1, #9 26c: 9afffff7 bls 250 n = n*10 + *s++ - '0'; return n; } 270: e28bd000 add sp, fp, #0 274: e8bd0800 pop {fp} 278: e12fff1e bx lr 0000027c : { char *dst, *src; dst = vdst; src = vsrc; while(n-- > 0) 27c: e3520000 cmp r2, #0 return n; } void* memmove(void *vdst, void *vsrc, int n) { 280: e52db004 push {fp} ; (str fp, [sp, #-4]!) 284: e28db000 add fp, sp, #0 char *dst, *src; dst = vdst; src = vsrc; while(n-- > 0) 288: da000005 ble 2a4 n = n*10 + *s++ - '0'; return n; } void* memmove(void *vdst, void *vsrc, int n) 28c: e0802002 add r2, r0, r2 { char *dst, *src; dst = vdst; 290: e1a03000 mov r3, r0 src = vsrc; while(n-- > 0) *dst++ = *src++; 294: e4d1c001 ldrb ip, [r1], #1 298: e4c3c001 strb ip, [r3], #1 { char *dst, *src; dst = vdst; src = vsrc; while(n-- > 0) 29c: e1530002 cmp r3, r2 2a0: 1afffffb bne 294 *dst++ = *src++; return vdst; } 2a4: e28bd000 add sp, fp, #0 2a8: e8bd0800 pop {fp} 2ac: e12fff1e bx lr 000002b0 : 2b0: e92d4000 push {lr} 2b4: e92d0008 push {r3} 2b8: e92d0004 push {r2} 2bc: e92d0002 push {r1} 2c0: e92d0001 push {r0} 2c4: e3a00001 mov r0, #1 2c8: ef000040 svc 0x00000040 2cc: e8bd0002 pop {r1} 2d0: e8bd0002 pop {r1} 2d4: e8bd0004 pop {r2} 2d8: e8bd0008 pop {r3} 2dc: e8bd4000 pop {lr} 2e0: e12fff1e bx lr 000002e4 : 2e4: e92d4000 push {lr} 2e8: e92d0008 push {r3} 2ec: e92d0004 push {r2} 2f0: e92d0002 push {r1} 2f4: e92d0001 push {r0} 2f8: e3a00002 mov r0, #2 2fc: ef000040 svc 0x00000040 300: e8bd0002 pop {r1} 304: e8bd0002 pop {r1} 308: e8bd0004 pop {r2} 30c: e8bd0008 pop {r3} 310: e8bd4000 pop {lr} 314: e12fff1e bx lr 00000318 : 318: e92d4000 push {lr} 31c: e92d0008 push {r3} 320: e92d0004 push {r2} 324: e92d0002 push {r1} 328: e92d0001 push {r0} 32c: e3a00003 mov r0, #3 330: ef000040 svc 0x00000040 334: e8bd0002 pop {r1} 338: e8bd0002 pop {r1} 33c: e8bd0004 pop {r2} 340: e8bd0008 pop {r3} 344: e8bd4000 pop {lr} 348: e12fff1e bx lr 0000034c : 34c: e92d4000 push {lr} 350: e92d0008 push {r3} 354: e92d0004 push {r2} 358: e92d0002 push {r1} 35c: e92d0001 push {r0} 360: e3a00004 mov r0, #4 364: ef000040 svc 0x00000040 368: e8bd0002 pop {r1} 36c: e8bd0002 pop {r1} 370: e8bd0004 pop {r2} 374: e8bd0008 pop {r3} 378: e8bd4000 pop {lr} 37c: e12fff1e bx lr 00000380 : 380: e92d4000 push {lr} 384: e92d0008 push {r3} 388: e92d0004 push {r2} 38c: e92d0002 push {r1} 390: e92d0001 push {r0} 394: e3a00005 mov r0, #5 398: ef000040 svc 0x00000040 39c: e8bd0002 pop {r1} 3a0: e8bd0002 pop {r1} 3a4: e8bd0004 pop {r2} 3a8: e8bd0008 pop {r3} 3ac: e8bd4000 pop {lr} 3b0: e12fff1e bx lr 000003b4 : 3b4: e92d4000 push {lr} 3b8: e92d0008 push {r3} 3bc: e92d0004 push {r2} 3c0: e92d0002 push {r1} 3c4: e92d0001 push {r0} 3c8: e3a00010 mov r0, #16 3cc: ef000040 svc 0x00000040 3d0: e8bd0002 pop {r1} 3d4: e8bd0002 pop {r1} 3d8: e8bd0004 pop {r2} 3dc: e8bd0008 pop {r3} 3e0: e8bd4000 pop {lr} 3e4: e12fff1e bx lr 000003e8 : 3e8: e92d4000 push {lr} 3ec: e92d0008 push {r3} 3f0: e92d0004 push {r2} 3f4: e92d0002 push {r1} 3f8: e92d0001 push {r0} 3fc: e3a00015 mov r0, #21 400: ef000040 svc 0x00000040 404: e8bd0002 pop {r1} 408: e8bd0002 pop {r1} 40c: e8bd0004 pop {r2} 410: e8bd0008 pop {r3} 414: e8bd4000 pop {lr} 418: e12fff1e bx lr 0000041c : 41c: e92d4000 push {lr} 420: e92d0008 push {r3} 424: e92d0004 push {r2} 428: e92d0002 push {r1} 42c: e92d0001 push {r0} 430: e3a00006 mov r0, #6 434: ef000040 svc 0x00000040 438: e8bd0002 pop {r1} 43c: e8bd0002 pop {r1} 440: e8bd0004 pop {r2} 444: e8bd0008 pop {r3} 448: e8bd4000 pop {lr} 44c: e12fff1e bx lr 00000450 : 450: e92d4000 push {lr} 454: e92d0008 push {r3} 458: e92d0004 push {r2} 45c: e92d0002 push {r1} 460: e92d0001 push {r0} 464: e3a00007 mov r0, #7 468: ef000040 svc 0x00000040 46c: e8bd0002 pop {r1} 470: e8bd0002 pop {r1} 474: e8bd0004 pop {r2} 478: e8bd0008 pop {r3} 47c: e8bd4000 pop {lr} 480: e12fff1e bx lr 00000484 : 484: e92d4000 push {lr} 488: e92d0008 push {r3} 48c: e92d0004 push {r2} 490: e92d0002 push {r1} 494: e92d0001 push {r0} 498: e3a0000f mov r0, #15 49c: ef000040 svc 0x00000040 4a0: e8bd0002 pop {r1} 4a4: e8bd0002 pop {r1} 4a8: e8bd0004 pop {r2} 4ac: e8bd0008 pop {r3} 4b0: e8bd4000 pop {lr} 4b4: e12fff1e bx lr 000004b8 : 4b8: e92d4000 push {lr} 4bc: e92d0008 push {r3} 4c0: e92d0004 push {r2} 4c4: e92d0002 push {r1} 4c8: e92d0001 push {r0} 4cc: e3a00011 mov r0, #17 4d0: ef000040 svc 0x00000040 4d4: e8bd0002 pop {r1} 4d8: e8bd0002 pop {r1} 4dc: e8bd0004 pop {r2} 4e0: e8bd0008 pop {r3} 4e4: e8bd4000 pop {lr} 4e8: e12fff1e bx lr 000004ec : 4ec: e92d4000 push {lr} 4f0: e92d0008 push {r3} 4f4: e92d0004 push {r2} 4f8: e92d0002 push {r1} 4fc: e92d0001 push {r0} 500: e3a00012 mov r0, #18 504: ef000040 svc 0x00000040 508: e8bd0002 pop {r1} 50c: e8bd0002 pop {r1} 510: e8bd0004 pop {r2} 514: e8bd0008 pop {r3} 518: e8bd4000 pop {lr} 51c: e12fff1e bx lr 00000520 : 520: e92d4000 push {lr} 524: e92d0008 push {r3} 528: e92d0004 push {r2} 52c: e92d0002 push {r1} 530: e92d0001 push {r0} 534: e3a00008 mov r0, #8 538: ef000040 svc 0x00000040 53c: e8bd0002 pop {r1} 540: e8bd0002 pop {r1} 544: e8bd0004 pop {r2} 548: e8bd0008 pop {r3} 54c: e8bd4000 pop {lr} 550: e12fff1e bx lr 00000554 : 554: e92d4000 push {lr} 558: e92d0008 push {r3} 55c: e92d0004 push {r2} 560: e92d0002 push {r1} 564: e92d0001 push {r0} 568: e3a00013 mov r0, #19 56c: ef000040 svc 0x00000040 570: e8bd0002 pop {r1} 574: e8bd0002 pop {r1} 578: e8bd0004 pop {r2} 57c: e8bd0008 pop {r3} 580: e8bd4000 pop {lr} 584: e12fff1e bx lr 00000588 : 588: e92d4000 push {lr} 58c: e92d0008 push {r3} 590: e92d0004 push {r2} 594: e92d0002 push {r1} 598: e92d0001 push {r0} 59c: e3a00014 mov r0, #20 5a0: ef000040 svc 0x00000040 5a4: e8bd0002 pop {r1} 5a8: e8bd0002 pop {r1} 5ac: e8bd0004 pop {r2} 5b0: e8bd0008 pop {r3} 5b4: e8bd4000 pop {lr} 5b8: e12fff1e bx lr 000005bc : 5bc: e92d4000 push {lr} 5c0: e92d0008 push {r3} 5c4: e92d0004 push {r2} 5c8: e92d0002 push {r1} 5cc: e92d0001 push {r0} 5d0: e3a00009 mov r0, #9 5d4: ef000040 svc 0x00000040 5d8: e8bd0002 pop {r1} 5dc: e8bd0002 pop {r1} 5e0: e8bd0004 pop {r2} 5e4: e8bd0008 pop {r3} 5e8: e8bd4000 pop {lr} 5ec: e12fff1e bx lr 000005f0 : 5f0: e92d4000 push {lr} 5f4: e92d0008 push {r3} 5f8: e92d0004 push {r2} 5fc: e92d0002 push {r1} 600: e92d0001 push {r0} 604: e3a0000a mov r0, #10 608: ef000040 svc 0x00000040 60c: e8bd0002 pop {r1} 610: e8bd0002 pop {r1} 614: e8bd0004 pop {r2} 618: e8bd0008 pop {r3} 61c: e8bd4000 pop {lr} 620: e12fff1e bx lr 00000624 : 624: e92d4000 push {lr} 628: e92d0008 push {r3} 62c: e92d0004 push {r2} 630: e92d0002 push {r1} 634: e92d0001 push {r0} 638: e3a0000b mov r0, #11 63c: ef000040 svc 0x00000040 640: e8bd0002 pop {r1} 644: e8bd0002 pop {r1} 648: e8bd0004 pop {r2} 64c: e8bd0008 pop {r3} 650: e8bd4000 pop {lr} 654: e12fff1e bx lr 00000658 : 658: e92d4000 push {lr} 65c: e92d0008 push {r3} 660: e92d0004 push {r2} 664: e92d0002 push {r1} 668: e92d0001 push {r0} 66c: e3a0000c mov r0, #12 670: ef000040 svc 0x00000040 674: e8bd0002 pop {r1} 678: e8bd0002 pop {r1} 67c: e8bd0004 pop {r2} 680: e8bd0008 pop {r3} 684: e8bd4000 pop {lr} 688: e12fff1e bx lr 0000068c : 68c: e92d4000 push {lr} 690: e92d0008 push {r3} 694: e92d0004 push {r2} 698: e92d0002 push {r1} 69c: e92d0001 push {r0} 6a0: e3a0000d mov r0, #13 6a4: ef000040 svc 0x00000040 6a8: e8bd0002 pop {r1} 6ac: e8bd0002 pop {r1} 6b0: e8bd0004 pop {r2} 6b4: e8bd0008 pop {r3} 6b8: e8bd4000 pop {lr} 6bc: e12fff1e bx lr 000006c0 : 6c0: e92d4000 push {lr} 6c4: e92d0008 push {r3} 6c8: e92d0004 push {r2} 6cc: e92d0002 push {r1} 6d0: e92d0001 push {r0} 6d4: e3a0000e mov r0, #14 6d8: ef000040 svc 0x00000040 6dc: e8bd0002 pop {r1} 6e0: e8bd0002 pop {r1} 6e4: e8bd0004 pop {r2} 6e8: e8bd0008 pop {r3} 6ec: e8bd4000 pop {lr} 6f0: e12fff1e bx lr 000006f4 : #include "stat.h" #include "user.h" static void putc(int fd, char c) { 6f4: e92d4800 push {fp, lr} 6f8: e28db004 add fp, sp, #4 6fc: e24b3004 sub r3, fp, #4 700: e24dd008 sub sp, sp, #8 write(fd, &c, 1); 704: e3a02001 mov r2, #1 #include "stat.h" #include "user.h" static void putc(int fd, char c) { 708: e5631001 strb r1, [r3, #-1]! write(fd, &c, 1); 70c: e1a01003 mov r1, r3 710: ebffff27 bl 3b4 } 714: e24bd004 sub sp, fp, #4 718: e8bd8800 pop {fp, pc} 0000071c : return q; } static void printint(int fd, int xx, int base, int sgn) { 71c: e92d4ff0 push {r4, r5, r6, r7, r8, r9, sl, fp, lr} 720: e1a04000 mov r4, r0 char buf[16]; int i, neg; uint x, y, b; neg = 0; if(sgn && xx < 0){ 724: e1a00fa1 lsr r0, r1, #31 728: e3530000 cmp r3, #0 72c: 03a03000 moveq r3, #0 730: 12003001 andne r3, r0, #1 return q; } static void printint(int fd, int xx, int base, int sgn) { 734: e28db020 add fp, sp, #32 char buf[16]; int i, neg; uint x, y, b; neg = 0; if(sgn && xx < 0){ 738: e3530000 cmp r3, #0 return q; } static void printint(int fd, int xx, int base, int sgn) { 73c: e24dd014 sub sp, sp, #20 740: e59f909c ldr r9, [pc, #156] ; 7e4 uint x, y, b; neg = 0; if(sgn && xx < 0){ neg = 1; x = -xx; 744: 12611000 rsbne r1, r1, #0 int i, neg; uint x, y, b; neg = 0; if(sgn && xx < 0){ neg = 1; 748: 13a03001 movne r3, #1 } else { x = xx; } b = base; i = 0; 74c: e3a0a000 mov sl, #0 750: e24b6034 sub r6, fp, #52 ; 0x34 for(i=31;i>=0;i--){ r = r << 1; r = r | ((n >> i) & 1); if(r >= d) { r = r - d; q = q | (1 << i); 754: e3a08001 mov r8, #1 write(fd, &c, 1); } u32 div(u32 n, u32 d) // long division { u32 q=0, r=0; 758: e3a07000 mov r7, #0 int i; for(i=31;i>=0;i--){ 75c: e3a0001f mov r0, #31 write(fd, &c, 1); } u32 div(u32 n, u32 d) // long division { u32 q=0, r=0; 760: e1a0c007 mov ip, r7 int i; for(i=31;i>=0;i--){ r = r << 1; r = r | ((n >> i) & 1); 764: e1a0e031 lsr lr, r1, r0 768: e20ee001 and lr, lr, #1 76c: e18ec08c orr ip, lr, ip, lsl #1 if(r >= d) { 770: e152000c cmp r2, ip r = r - d; q = q | (1 << i); 774: 91877018 orrls r7, r7, r8, lsl r0 for(i=31;i>=0;i--){ r = r << 1; r = r | ((n >> i) & 1); if(r >= d) { r = r - d; 778: 9062c00c rsbls ip, r2, ip u32 div(u32 n, u32 d) // long division { u32 q=0, r=0; int i; for(i=31;i>=0;i--){ 77c: e2500001 subs r0, r0, #1 780: 2afffff7 bcs 764 b = base; i = 0; do{ y = div(x, b); buf[i++] = digits[x - y * b]; 784: e0000792 mul r0, r2, r7 }while((x = y) != 0); 788: e3570000 cmp r7, #0 b = base; i = 0; do{ y = div(x, b); buf[i++] = digits[x - y * b]; 78c: e0601001 rsb r1, r0, r1 790: e28a5001 add r5, sl, #1 794: e7d91001 ldrb r1, [r9, r1] 798: e7c6100a strb r1, [r6, sl] }while((x = y) != 0); 79c: 11a01007 movne r1, r7 b = base; i = 0; do{ y = div(x, b); buf[i++] = digits[x - y * b]; 7a0: 11a0a005 movne sl, r5 7a4: 1affffeb bne 758 }while((x = y) != 0); if(neg) 7a8: e3530000 cmp r3, #0 buf[i++] = '-'; 7ac: 124b2024 subne r2, fp, #36 ; 0x24 7b0: 10823005 addne r3, r2, r5 7b4: 128a5002 addne r5, sl, #2 while(--i >= 0) 7b8: e2455001 sub r5, r5, #1 do{ y = div(x, b); buf[i++] = digits[x - y * b]; }while((x = y) != 0); if(neg) buf[i++] = '-'; 7bc: 13a0202d movne r2, #45 ; 0x2d 7c0: 15432010 strbne r2, [r3, #-16] while(--i >= 0) putc(fd, buf[i]); 7c4: e7d61005 ldrb r1, [r6, r5] 7c8: e1a00004 mov r0, r4 buf[i++] = digits[x - y * b]; }while((x = y) != 0); if(neg) buf[i++] = '-'; while(--i >= 0) 7cc: e2455001 sub r5, r5, #1 putc(fd, buf[i]); 7d0: ebffffc7 bl 6f4 buf[i++] = digits[x - y * b]; }while((x = y) != 0); if(neg) buf[i++] = '-'; while(--i >= 0) 7d4: e3750001 cmn r5, #1 7d8: 1afffff9 bne 7c4 putc(fd, buf[i]); } 7dc: e24bd020 sub sp, fp, #32 7e0: e8bd8ff0 pop {r4, r5, r6, r7, r8, r9, sl, fp, pc} 7e4: 00000b38 .word 0x00000b38 000007e8
: write(fd, &c, 1); } u32 div(u32 n, u32 d) // long division { u32 q=0, r=0; 7e8: e3a03000 mov r3, #0 { write(fd, &c, 1); } u32 div(u32 n, u32 d) // long division { 7ec: e92d0830 push {r4, r5, fp} 7f0: e1a02000 mov r2, r0 7f4: e28db008 add fp, sp, #8 u32 q=0, r=0; int i; for(i=31;i>=0;i--){ 7f8: e3a0c01f mov ip, #31 write(fd, &c, 1); } u32 div(u32 n, u32 d) // long division { u32 q=0, r=0; 7fc: e1a00003 mov r0, r3 for(i=31;i>=0;i--){ r = r << 1; r = r | ((n >> i) & 1); if(r >= d) { r = r - d; q = q | (1 << i); 800: e3a05001 mov r5, #1 u32 q=0, r=0; int i; for(i=31;i>=0;i--){ r = r << 1; r = r | ((n >> i) & 1); 804: e1a04c32 lsr r4, r2, ip 808: e2044001 and r4, r4, #1 80c: e1843083 orr r3, r4, r3, lsl #1 if(r >= d) { 810: e1530001 cmp r3, r1 r = r - d; q = q | (1 << i); 814: 21800c15 orrcs r0, r0, r5, lsl ip for(i=31;i>=0;i--){ r = r << 1; r = r | ((n >> i) & 1); if(r >= d) { r = r - d; 818: 20613003 rsbcs r3, r1, r3 u32 div(u32 n, u32 d) // long division { u32 q=0, r=0; int i; for(i=31;i>=0;i--){ 81c: e25cc001 subs ip, ip, #1 820: 2afffff7 bcs 804 r = r - d; q = q | (1 << i); } } return q; } 824: e24bd008 sub sp, fp, #8 828: e8bd0830 pop {r4, r5, fp} 82c: e12fff1e bx lr 00000830 : } // Print to the given fd. Only understands %d, %x, %p, %s. void printf(int fd, char *fmt, ...) { 830: e92d000e push {r1, r2, r3} 834: e92d4ff0 push {r4, r5, r6, r7, r8, r9, sl, fp, lr} 838: e28db020 add fp, sp, #32 83c: e1a05000 mov r5, r0 int c, i, state; uint *ap; state = 0; ap = (uint*)(void*)&fmt + 1; for(i = 0; fmt[i]; i++){ 840: e59b4004 ldr r4, [fp, #4] 844: e5d48000 ldrb r8, [r4] 848: e3580000 cmp r8, #0 84c: 0a000027 beq 8f0 ap++; } else if(c == 's'){ s = (char*)*ap; ap++; if(s == 0) s = "(null)"; 850: e59f712c ldr r7, [pc, #300] ; 984 char *s; int c, i, state; uint *ap; state = 0; ap = (uint*)(void*)&fmt + 1; 854: e28b6008 add r6, fp, #8 { char *s; int c, i, state; uint *ap; state = 0; 858: e3a0a000 mov sl, #0 85c: ea000008 b 884 ap = (uint*)(void*)&fmt + 1; for(i = 0; fmt[i]; i++){ c = fmt[i] & 0xff; if(state == 0){ if(c == '%'){ 860: e3580025 cmp r8, #37 ; 0x25 state = '%'; 864: 01a0a008 moveq sl, r8 state = 0; ap = (uint*)(void*)&fmt + 1; for(i = 0; fmt[i]; i++){ c = fmt[i] & 0xff; if(state == 0){ if(c == '%'){ 868: 0a000002 beq 878 state = '%'; } else { putc(fd, c); 86c: e1a00005 mov r0, r5 870: e1a01008 mov r1, r8 874: ebffff9e bl 6f4 int c, i, state; uint *ap; state = 0; ap = (uint*)(void*)&fmt + 1; for(i = 0; fmt[i]; i++){ 878: e5f48001 ldrb r8, [r4, #1]! 87c: e3580000 cmp r8, #0 880: 0a00001a beq 8f0 c = fmt[i] & 0xff; if(state == 0){ 884: e35a0000 cmp sl, #0 888: 0afffff4 beq 860 if(c == '%'){ state = '%'; } else { putc(fd, c); } } else if(state == '%'){ 88c: e35a0025 cmp sl, #37 ; 0x25 890: 1afffff8 bne 878 if(c == 'd'){ 894: e3580064 cmp r8, #100 ; 0x64 898: 0a00002c beq 950 printint(fd, *ap, 10, 1); ap++; } else if(c == 'x' || c == 'p'){ 89c: e3580078 cmp r8, #120 ; 0x78 8a0: 13580070 cmpne r8, #112 ; 0x70 8a4: 13a09000 movne r9, #0 8a8: 03a09001 moveq r9, #1 8ac: 0a000013 beq 900 printint(fd, *ap, 16, 0); ap++; } else if(c == 's'){ 8b0: e3580073 cmp r8, #115 ; 0x73 8b4: 0a000018 beq 91c s = "(null)"; while(*s != 0){ putc(fd, *s); s++; } } else if(c == 'c'){ 8b8: e3580063 cmp r8, #99 ; 0x63 8bc: 0a00002a beq 96c putc(fd, *ap); ap++; } else if(c == '%'){ 8c0: e3580025 cmp r8, #37 ; 0x25 putc(fd, c); 8c4: e1a0100a mov r1, sl 8c8: e1a00005 mov r0, r5 s++; } } else if(c == 'c'){ putc(fd, *ap); ap++; } else if(c == '%'){ 8cc: 0a000002 beq 8dc putc(fd, c); } else { // Unknown % sequence. Print it to draw attention. putc(fd, '%'); 8d0: ebffff87 bl 6f4 putc(fd, c); 8d4: e1a00005 mov r0, r5 8d8: e1a01008 mov r1, r8 8dc: ebffff84 bl 6f4 int c, i, state; uint *ap; state = 0; ap = (uint*)(void*)&fmt + 1; for(i = 0; fmt[i]; i++){ 8e0: e5f48001 ldrb r8, [r4, #1]! } else { // Unknown % sequence. Print it to draw attention. putc(fd, '%'); putc(fd, c); } state = 0; 8e4: e1a0a009 mov sl, r9 int c, i, state; uint *ap; state = 0; ap = (uint*)(void*)&fmt + 1; for(i = 0; fmt[i]; i++){ 8e8: e3580000 cmp r8, #0 8ec: 1affffe4 bne 884 putc(fd, c); } state = 0; } } } 8f0: e24bd020 sub sp, fp, #32 8f4: e8bd4ff0 pop {r4, r5, r6, r7, r8, r9, sl, fp, lr} 8f8: e28dd00c add sp, sp, #12 8fc: e12fff1e bx lr } else if(state == '%'){ if(c == 'd'){ printint(fd, *ap, 10, 1); ap++; } else if(c == 'x' || c == 'p'){ printint(fd, *ap, 16, 0); 900: e1a00005 mov r0, r5 904: e4961004 ldr r1, [r6], #4 908: e3a02010 mov r2, #16 90c: e3a03000 mov r3, #0 910: ebffff81 bl 71c } else { // Unknown % sequence. Print it to draw attention. putc(fd, '%'); putc(fd, c); } state = 0; 914: e3a0a000 mov sl, #0 918: eaffffd6 b 878 ap++; } else if(c == 'x' || c == 'p'){ printint(fd, *ap, 16, 0); ap++; } else if(c == 's'){ s = (char*)*ap; 91c: e4968004 ldr r8, [r6], #4 ap++; if(s == 0) s = "(null)"; 920: e3580000 cmp r8, #0 924: 01a08007 moveq r8, r7 while(*s != 0){ 928: e5d81000 ldrb r1, [r8] 92c: e3510000 cmp r1, #0 930: 0a000004 beq 948 putc(fd, *s); 934: e1a00005 mov r0, r5 938: ebffff6d bl 6f4 } else if(c == 's'){ s = (char*)*ap; ap++; if(s == 0) s = "(null)"; while(*s != 0){ 93c: e5f81001 ldrb r1, [r8, #1]! 940: e3510000 cmp r1, #0 944: 1afffffa bne 934 } else { // Unknown % sequence. Print it to draw attention. putc(fd, '%'); putc(fd, c); } state = 0; 948: e1a0a001 mov sl, r1 94c: eaffffc9 b 878 } else { putc(fd, c); } } else if(state == '%'){ if(c == 'd'){ printint(fd, *ap, 10, 1); 950: e1a00005 mov r0, r5 954: e4961004 ldr r1, [r6], #4 958: e3a0200a mov r2, #10 95c: e3a03001 mov r3, #1 960: ebffff6d bl 71c } else { // Unknown % sequence. Print it to draw attention. putc(fd, '%'); putc(fd, c); } state = 0; 964: e3a0a000 mov sl, #0 968: eaffffc2 b 878 while(*s != 0){ putc(fd, *s); s++; } } else if(c == 'c'){ putc(fd, *ap); 96c: e4961004 ldr r1, [r6], #4 970: e1a00005 mov r0, r5 } else { // Unknown % sequence. Print it to draw attention. putc(fd, '%'); putc(fd, c); } state = 0; 974: e1a0a009 mov sl, r9 while(*s != 0){ putc(fd, *s); s++; } } else if(c == 'c'){ putc(fd, *ap); 978: e6ef1071 uxtb r1, r1 97c: ebffff5c bl 6f4 980: eaffffbc b 878 984: 00000b4c .word 0x00000b4c 00000988 : free(void *ap) { Header *bp, *p; bp = (Header*)ap - 1; for(p = freep; !(bp > p && bp < p->s.ptr); p = p->s.ptr) 988: e59f3098 ldr r3, [pc, #152] ; a28 static Header base; static Header *freep; void free(void *ap) { 98c: e92d0830 push {r4, r5, fp} Header *bp, *p; bp = (Header*)ap - 1; 990: e240c008 sub ip, r0, #8 for(p = freep; !(bp > p && bp < p->s.ptr); p = p->s.ptr) 994: e5932000 ldr r2, [r3] static Header base; static Header *freep; void free(void *ap) { 998: e28db008 add fp, sp, #8 Header *bp, *p; bp = (Header*)ap - 1; for(p = freep; !(bp > p && bp < p->s.ptr); p = p->s.ptr) 99c: e152000c cmp r2, ip 9a0: e5921000 ldr r1, [r2] 9a4: 2a000001 bcs 9b0 9a8: e15c0001 cmp ip, r1 9ac: 3a000007 bcc 9d0 if(p >= p->s.ptr && (bp > p || bp < p->s.ptr)) 9b0: e1520001 cmp r2, r1 9b4: 3a000003 bcc 9c8 9b8: e152000c cmp r2, ip 9bc: 3a000003 bcc 9d0 9c0: e15c0001 cmp ip, r1 9c4: 3a000001 bcc 9d0 static Header base; static Header *freep; void free(void *ap) { 9c8: e1a02001 mov r2, r1 9cc: eafffff2 b 99c bp = (Header*)ap - 1; for(p = freep; !(bp > p && bp < p->s.ptr); p = p->s.ptr) if(p >= p->s.ptr && (bp > p || bp < p->s.ptr)) break; if(bp + bp->s.size == p->s.ptr){ 9d0: e5104004 ldr r4, [r0, #-4] if(p + p->s.size == bp){ p->s.size += bp->s.size; p->s.ptr = bp->s.ptr; } else p->s.ptr = bp; freep = p; 9d4: e5832000 str r2, [r3] bp = (Header*)ap - 1; for(p = freep; !(bp > p && bp < p->s.ptr); p = p->s.ptr) if(p >= p->s.ptr && (bp > p || bp < p->s.ptr)) break; if(bp + bp->s.size == p->s.ptr){ 9d8: e08c5184 add r5, ip, r4, lsl #3 9dc: e1550001 cmp r5, r1 bp->s.size += p->s.ptr->s.size; 9e0: 05911004 ldreq r1, [r1, #4] 9e4: 00814004 addeq r4, r1, r4 9e8: 05004004 streq r4, [r0, #-4] bp->s.ptr = p->s.ptr->s.ptr; 9ec: 05921000 ldreq r1, [r2] 9f0: 05911000 ldreq r1, [r1] } else bp->s.ptr = p->s.ptr; 9f4: e5001008 str r1, [r0, #-8] if(p + p->s.size == bp){ 9f8: e5921004 ldr r1, [r2, #4] 9fc: e0824181 add r4, r2, r1, lsl #3 a00: e15c0004 cmp ip, r4 p->s.size += bp->s.size; p->s.ptr = bp->s.ptr; } else p->s.ptr = bp; a04: 1582c000 strne ip, [r2] bp->s.size += p->s.ptr->s.size; bp->s.ptr = p->s.ptr->s.ptr; } else bp->s.ptr = p->s.ptr; if(p + p->s.size == bp){ p->s.size += bp->s.size; a08: 0510c004 ldreq ip, [r0, #-4] a0c: 008c1001 addeq r1, ip, r1 a10: 05821004 streq r1, [r2, #4] p->s.ptr = bp->s.ptr; a14: 05101008 ldreq r1, [r0, #-8] a18: 05821000 streq r1, [r2] } else p->s.ptr = bp; freep = p; } a1c: e24bd008 sub sp, fp, #8 a20: e8bd0830 pop {r4, r5, fp} a24: e12fff1e bx lr a28: 00000b54 .word 0x00000b54 00000a2c : return freep; } void* malloc(uint nbytes) { a2c: e92d49f8 push {r3, r4, r5, r6, r7, r8, fp, lr} Header *p, *prevp; uint nunits; nunits = (nbytes + sizeof(Header) - 1)/sizeof(Header) + 1; a30: e2804007 add r4, r0, #7 if((prevp = freep) == 0){ a34: e59f50d4 ldr r5, [pc, #212] ; b10 malloc(uint nbytes) { Header *p, *prevp; uint nunits; nunits = (nbytes + sizeof(Header) - 1)/sizeof(Header) + 1; a38: e1a041a4 lsr r4, r4, #3 return freep; } void* malloc(uint nbytes) { a3c: e28db01c add fp, sp, #28 Header *p, *prevp; uint nunits; nunits = (nbytes + sizeof(Header) - 1)/sizeof(Header) + 1; if((prevp = freep) == 0){ a40: e5953000 ldr r3, [r5] malloc(uint nbytes) { Header *p, *prevp; uint nunits; nunits = (nbytes + sizeof(Header) - 1)/sizeof(Header) + 1; a44: e2844001 add r4, r4, #1 if((prevp = freep) == 0){ a48: e3530000 cmp r3, #0 a4c: 0a00002b beq b00 a50: e5930000 ldr r0, [r3] a54: e5902004 ldr r2, [r0, #4] base.s.ptr = freep = prevp = &base; base.s.size = 0; } for(p = prevp->s.ptr; ; prevp = p, p = p->s.ptr){ if(p->s.size >= nunits){ a58: e1520004 cmp r2, r4 a5c: 2a00001b bcs ad0 morecore(uint nu) { char *p; Header *hp; if(nu < 4096) a60: e59f80ac ldr r8, [pc, #172] ; b14 p->s.size -= nunits; p += p->s.size; p->s.size = nunits; } freep = prevp; return (void*)(p + 1); a64: e1a07184 lsl r7, r4, #3 a68: ea000003 b a7c nunits = (nbytes + sizeof(Header) - 1)/sizeof(Header) + 1; if((prevp = freep) == 0){ base.s.ptr = freep = prevp = &base; base.s.size = 0; } for(p = prevp->s.ptr; ; prevp = p, p = p->s.ptr){ a6c: e5930000 ldr r0, [r3] if(p->s.size >= nunits){ a70: e5902004 ldr r2, [r0, #4] a74: e1540002 cmp r4, r2 a78: 9a000014 bls ad0 p->s.size = nunits; } freep = prevp; return (void*)(p + 1); } if(p == freep) a7c: e5952000 ldr r2, [r5] a80: e1a03000 mov r3, r0 a84: e1500002 cmp r0, r2 a88: 1afffff7 bne a6c morecore(uint nu) { char *p; Header *hp; if(nu < 4096) a8c: e1540008 cmp r4, r8 nu = 4096; p = sbrk(nu * sizeof(Header)); a90: 81a00007 movhi r0, r7 a94: 93a00902 movls r0, #32768 ; 0x8000 morecore(uint nu) { char *p; Header *hp; if(nu < 4096) a98: 81a06004 movhi r6, r4 a9c: 93a06a01 movls r6, #4096 ; 0x1000 nu = 4096; p = sbrk(nu * sizeof(Header)); aa0: ebfffeec bl 658 aa4: e1a03000 mov r3, r0 if(p == (char*)-1) aa8: e3730001 cmn r3, #1 return 0; hp = (Header*)p; hp->s.size = nu; free((void*)(hp + 1)); aac: e2800008 add r0, r0, #8 Header *hp; if(nu < 4096) nu = 4096; p = sbrk(nu * sizeof(Header)); if(p == (char*)-1) ab0: 0a000010 beq af8 return 0; hp = (Header*)p; hp->s.size = nu; ab4: e5836004 str r6, [r3, #4] free((void*)(hp + 1)); ab8: ebffffb2 bl 988 return freep; abc: e5953000 ldr r3, [r5] } freep = prevp; return (void*)(p + 1); } if(p == freep) if((p = morecore(nunits)) == 0) ac0: e3530000 cmp r3, #0 ac4: 1affffe8 bne a6c return 0; ac8: e1a00003 mov r0, r3 } } acc: e8bd89f8 pop {r3, r4, r5, r6, r7, r8, fp, pc} base.s.ptr = freep = prevp = &base; base.s.size = 0; } for(p = prevp->s.ptr; ; prevp = p, p = p->s.ptr){ if(p->s.size >= nunits){ if(p->s.size == nunits) ad0: e1540002 cmp r4, r2 prevp->s.ptr = p->s.ptr; else { p->s.size -= nunits; ad4: 10642002 rsbne r2, r4, r2 ad8: 15802004 strne r2, [r0, #4] base.s.size = 0; } for(p = prevp->s.ptr; ; prevp = p, p = p->s.ptr){ if(p->s.size >= nunits){ if(p->s.size == nunits) prevp->s.ptr = p->s.ptr; adc: 05902000 ldreq r2, [r0] else { p->s.size -= nunits; p += p->s.size; ae0: 10800182 addne r0, r0, r2, lsl #3 base.s.size = 0; } for(p = prevp->s.ptr; ; prevp = p, p = p->s.ptr){ if(p->s.size >= nunits){ if(p->s.size == nunits) prevp->s.ptr = p->s.ptr; ae4: 05832000 streq r2, [r3] else { p->s.size -= nunits; p += p->s.size; p->s.size = nunits; ae8: 15804004 strne r4, [r0, #4] } freep = prevp; aec: e5853000 str r3, [r5] return (void*)(p + 1); af0: e2800008 add r0, r0, #8 af4: e8bd89f8 pop {r3, r4, r5, r6, r7, r8, fp, pc} } if(p == freep) if((p = morecore(nunits)) == 0) return 0; af8: e3a00000 mov r0, #0 afc: e8bd89f8 pop {r3, r4, r5, r6, r7, r8, fp, pc} Header *p, *prevp; uint nunits; nunits = (nbytes + sizeof(Header) - 1)/sizeof(Header) + 1; if((prevp = freep) == 0){ base.s.ptr = freep = prevp = &base; b00: e2850004 add r0, r5, #4 b04: e5850000 str r0, [r5] base.s.size = 0; b08: e9850009 stmib r5, {r0, r3} b0c: eaffffd3 b a60 b10: 00000b54 .word 0x00000b54 b14: 00000fff .word 0x00000fff