CS 410 Project One Proficiency Test Template

CS 410 Project One Proficiency Test Template Explain the functionality of the blocks of assembly code. “main” function” Assembly Code Block Explanation of Functionality 0: push %rbp 1: mov %rsp,%rbp Pushes the base pointer to the stack and moves the stack pointer to the base pointer. No allocation of bytes for this function 4: lea 0x0(%rip),%rsi # b <main+0xb> b: lea 0x0(%rip),%rdi # 12 <main+0x12> 12: callq 17 <main+0x17> Loads the address of the current instruction pointer (b) to %rsi Loads the address of the current instruction pointer (12) to %rdi Calls a function located at 17 with %rdi and %rsi as the 1 st and 2 nd arguments (quadword return commonly implemented as 64bits/8bytes) 17: callq 1c <main+0x1c> 1c: mov %eax,0x0(%rip) # 22 <main+0x22> 22: mov 0x0(%rip),%eax # 28 <main+0x28> 28: cmp $0x1,%eax 2b: je 40 <main+0x40> 2d: lea 0x0(%rip),%rsi # 34 <main+0x34> 34: lea 0x0(%rip),%rdi # 3b <main+0x3b> 3b: callq 40 <main+0x40> 40: mov 0x0(%rip),%eax # 46 <main+0x46> 46: cmp $0x1,%eax 49: je 4d <main+0x4d> 4b: jmp 17 <main+0x17> [START OF 1ST LOOP] Calls a function located at 1c Moves %eax (the lower 32 bits of the value returned by the previous function call) to the instruction pointer Moves the value at the instruction pointer back to %eax Compares a value of 1 to the value at %eax if %eax is greater than then the program will jump to 40 otherwise the following indented instructions will run Loads the address of the current instruction pointer (34) to %rsi Loads the address of the current instruction pointer (3b) to %rdi Calls a function located at 40 Moves the value of the current instruction pointer to %eax Compares the value of 1 to the value at %eax Jumps to 4d if they are equal thus ending the 1 st loop otherwise jump to 17 [END OF 1ST LOOP] 4d: lea 0x0(%rip),%rsi # 54 <main+0x54> [4D: START OF 2ND LOOP] Loads the address of the current instruction pointer (54) to %rsi 1

54: lea 0x0(%rip),%rdi # 5b <main+0x5b> 5b: callq 60 <main+0x60> 60: lea 0x0(%rip),%rsi # 67 <main+0x67> 67: lea 0x0(%rip),%rdi # 6e <main+0x6e> 6e: callq 73 <main+0x73> 73: lea 0x0(%rip),%rsi # 7a <main+0x7a> 7a: lea 0x0(%rip),%rdi # 81 <main+0x81> 81: callq 86 <main+0x86> 86: lea 0x0(%rip),%rsi # 8d <main+0x8d> 8d: lea 0x0(%rip),%rdi # 94 <main+0x94> 94: callq 99 <main+0x99> 99: lea 0x0(%rip),%rsi # a0 <main+0xa0> a0: lea 0x0(%rip),%rdi # a7 <main+0xa7> a7: callq ac <main+0xac> Loads the address of the current instruction pointer (5b) to %rdi Calls a function located at 60 with %rdi and %rsi as the 1 st and 2 nd arguments Loads the address of the current instruction pointer (67) to %rsi Loads the address of the current instruction pointer (6e) to %rdi Calls a function located at 73 with %rdi and %rsi as the 1 st and 2 nd arguments Loads the address of the current instruction pointer (7a) to %rsi Loads the address of the current instruction pointer (81) to %rdi Calls a function located at 86 with %rdi and %rsi as the 1 st and 2 nd arguments Loads the address of the current instruction pointer (8d) to %rsi Loads the address of the current instruction pointer (94) to %rdi Calls a function located at 99 with %rdi and %rsi as the 1 st and 2 nd arguments Loads the address of the current instruction pointer (a0) to %rsi Loads the address of the current instruction pointer (a7) to %rdi Calls a function located at ac with %rdi and %rsi as the 1 st and 2 nd arguments ac: lea 0x0(%rip),%rsi # b3 <main+0xb3> b3: lea 0x0(%rip),%rdi # ba <main+0xba> ba: callq bf <main+0xbf> bf: mov %rax,%rdx c2: mov 0x0(%rip),%eax # c8 <main+0xc8> c8: mov %eax,%esi ca: mov %rdx,%rdi cd: callq d2 <main+0xd2> d2: mov %rax,%rdx d5: mov 0x0(%rip),%rax # dc <main+0xdc> Loads the address of the current instruction pointer (b3) to %rsi Loads the address of the current instruction pointer (ba) to %rdi Calls a function located at bf with %rdi and %rsi as the 1st and 2nd arguments Moves %rax (the value of the previous function call) to %rdx Moves the value of the current instruction pointer (c8) to %eax Moves the value at %eax to %esi Moves the value at %rdx to %rdi Calls a function located at d2 with %rdi and %rsi as the 1st and 2nd arguments Moves %rax (the value of the previous function call) to %rdx Moves the value of the current instruction pointer (dc) to %rax Moves the value at %rax to %rsi 2

ChangeCustomerChoice function Assembly Code Block Explanation of Functionality 42d: push %rbp 42e: mov %rsp,%rbp 431: lea 0x0(%rip),%rsi # 438 <_Z20ChangeCustomerChoicev+0xb> 438: lea 0x0(%rip),%rdi # 43f <_Z20ChangeCustomerChoicev+0x12> 43f: callq 444 <_Z20ChangeCustomerChoicev+0x17> 444: lea 0x0(%rip),%rsi # 44b <_Z20ChangeCustomerChoicev+0x1e> 44b: lea 0x0(%rip),%rdi # 452 <_Z20ChangeCustomerChoicev+0x25> 452: callq 457 <_Z20ChangeCustomerChoicev+0x2a> 457: lea 0x0(%rip),%rsi # 45e <_Z20ChangeCustomerChoicev+0x31> 45e: lea 0x0(%rip),%rdi # 465 <_Z20ChangeCustomerChoicev+0x38> 465: callq 46a <_Z20ChangeCustomerChoicev+0x3d> 46a: lea 0x0(%rip),%rsi # 471 <_Z20ChangeCustomerChoicev+0x44> 471: lea 0x0(%rip),%rdi # 478 <_Z20ChangeCustomerChoicev+0x4b> 478: callq 47d <_Z20ChangeCustomerChoicev+0x50> Pushes the base pointer to the stack Moves the stack pointer to the base pointer Loads the current address of the instruction pointer to %rsi Loads the current address of the instruction pointer to %rdi Calls a function located at 444 with %rdi and %rsi as the 1 st and 2 nd arguments Loads the current address of the instruction pointer to %rsi Loads the current address of the instruction pointer to %rdi Calls a function located at 457 with %rdi and %rsi as the 1 st and 2 nd arguments Loads the current address of the instruction pointer to %rsi Loads the current address of the instruction pointer to %rdi Calls a function located at 46a with %rdi and %rsi as the 1 st and 2 nd arguments Loads the current address of the instruction pointer to %rsi Loads the current address of the instruction pointer to %rdi Calls a function located at 47d with %rdi and %rsi as the 1 st and 2 nd arguments 47d: mov 0x0(%rip),%eax # 483 <_Z20ChangeCustomerChoicev+0x56> [START OF MAIN LOOP] Moves the current value of the instruction pointer to %eax Compares the value of 1 to the value at %eax 4

Assembly Code Block Explanation of Functionality 483: cmp $0x1,%eax 486: jne 496 <_Z20ChangeCustomerChoicev+0x69> 488: mov 0x0(%rip),%eax # 48e <_Z20ChangeCustomerChoicev+0x61> 48e: mov %eax,0x0(%rip) # 494 <_Z20ChangeCustomerChoicev+0x67> 494: jmp 4f8 <_Z20ChangeCustomerChoicev+0xcb> Jumps to 496 if they are not equal otherwise the indented instructions will run Moves the current value of the instruction pointer to %eax Moves the value at %eax to the current value of the instruction pointer Jumps to 4f8 (end of main loop) 496: mov 0x0(%rip),%eax # 49c <_Z20ChangeCustomerChoicev+0x6f> 49c: cmp $0x2,%eax 49f: jne 4af <_Z20ChangeCustomerChoicev+0x82> 4a1: mov 0x0(%rip),%eax # 4a7 <_Z20ChangeCustomerChoicev+0x7a> 4a7: mov %eax,0x0(%rip) # 4ad <_Z20ChangeCustomerChoicev+0x80> 4ad: jmp 4f8 <_Z20ChangeCustomerChoicev+0xcb> Moves the current value of the instruction pointer to %eax Compares the value of 2 to the value at %eax Jumps to 4af if they are not equal otherwise the indented instructions will run Moves the current value of the instruction pointer to %eax Moves the value at %eax to the current value of the instruction pointer Jumps to 4f8 (end of main loop) 4af: mov 0x0(%rip),%eax # 4b5 <_Z20ChangeCustomerChoicev+0x88> 4b5: cmp $0x3,%eax 4b8: jne 4c8 <_Z20ChangeCustomerChoicev+0x9b> 4ba: mov 0x0(%rip),%eax # 4c0 <_Z20ChangeCustomerChoicev+0x93> 4c0: mov %eax,0x0(%rip) # 4c6 <_Z20ChangeCustomerChoicev+0x99> Moves the current value of the instruction pointer to %eax Compares the value of 3 to the value at %eax Jumps to 4c8 if they are not equal otherwise the indented instructions will run Moves the current value of the instruction pointer to %eax Moves the value at %eax to the current value of the instruction pointer Jumps to 4f8 (end of main loop) 5

Assembly Code Block Explanation of Functionality 121: mov %rsp,%rbp 124: push %rbx 125: sub $0x48,%rsp 129: mov %fs:0x28,%rax 130: 00 00 132: mov %rax,-0x18(%rbp) 136: xor %eax,%eax Pushes %rbx on the stack Allocates 0x48 (72) bytes by subtracting it from the stack pointer Moves the value at %fs:0x28 to %rax and from %rax to -0x18(%rbp) Xors %eax to itself effectively setting it to zero 138: lea -0x45(%rbp),%rax 13c: mov %rax,%rdi 13f: callq 144 <_Z25CheckUserPermissionAccessv+0x24> 144: lea -0x45(%rbp),%rdx 148: lea -0x40(%rbp),%rax 14c: lea 0x0(%rip),%rsi # 153 <_Z25CheckUserPermissionAccessv+0x33> 153: mov %rax,%rdi 156: callq 15b <_Z25CheckUserPermissionAccessv+0x3b> 15b: lea -0x45(%rbp),%rax 15f: mov %rax,%rdi 162: callq 167 <_Z25CheckUserPermissionAccessv+0x47> 167: movl $0x0,-0x44(%rbp) 16e: lea 0x0(%rip),%rsi # 175 <_Z25CheckUserPermissionAccessv+0x55> 175: lea 0x0(%rip),%rdi # 17c <_Z25CheckUserPermissionAccessv+0x5c> Loads the effective address of -0x45(%rbp) to %rax Moves the value at %rax to %rdi Calls a function at 144 with %rdi as the 1 st argument Loads the effective address of -0x45(%rbp) to %rdx Loads the effective address of -0x40(%rbp) to %rax Loads the effective address of the current instruction pointer to %rsi Moves the value at %rax to %rdi Calls a function located at 15b with %rdi, and %rsi as the 1 st and 2 nd arguments Loads the effective address of -45(%rbp) to %rax Moves the value at %rax to %rdi Calls a function located at 167 with %rdi as the 1 st argument Moves a value of zero to -0x44(%rbp) Loads the effective address of the current instruction pointer to %rsi Loads the effective address of the current instruction pointer to %rdi Calls a function located at 181 with %rdi and %rsi as the 1 st and 2 nd arguments Loads the effective address of the current instruction pointer to %rsi Loads the effective address of the current instruction pointer to %rdi Calls a function located at 194 with %rdi and %rsi as the 1 st and 2 nd arguments Loads the effective address of the current instruction pointer to %rsi Loads the effective address of the current instruction pointer to %rdi Calls a function located at 1a7 with %rdi and %rsi as the 1 st and 2 nd arguments 7

Assembly Code Block Explanation of Functionality 17c: callq 181 <_Z25CheckUserPermissionAccessv+0x61> 181: lea 0x0(%rip),% rsi # 188 <_Z25CheckUserPermissionAccessv+0x68> 188: lea 0x0(%rip),%rdi # 18f <_Z25CheckUserPermissionAccessv+0x6f> 18f: callq 194 <_Z25CheckUserPermissionAccessv+0x74> 194: lea 0x0(%rip),%rsi # 19b <_Z25CheckUserPermissionAccessv+0x7b> 19b: lea 0x0(%rip),%rdi # 1a2 <_Z25CheckUserPermissionAccessv+0x82> 1a2: callq 1a7 <_Z25CheckUserPermissionAccessv+0x87> 1a7: lea -0x40(%rbp),%rax 1ab: mov %rax,%rsi 1ae: lea 0x0(%rip),%rdi # 1b5 <_Z25CheckUserPermissionAccessv+0x95> 1b5: callq 1ba <_Z25CheckUserPermissionAccessv+0x9a> 1ba: lea -0x40(%rbp),%rax 1be: lea 0x0(%rip),%rsi # 1c5 <_Z25CheckUserPermissionAccessv+0xa5> 1c5: mov %rax,%rdi 1c8: callq 1cd <_Z25CheckUserPermissionAccessv+0xad> 1cd: mov %eax,-0x44(%rbp) 1d0: cmpl $0x0,-0x44(%rbp) 1d4: jne 1dd Loads the effective address of -0x40(%rbp) to %rax Moves the value at %rax to %rsi Loads the effective address of the current instruction pointer to %rdi Calls a function located at 1ba with %rdi and %rsi as the 1 st and 2 nd arguments Loads the effective address of -0x40(%rbp) to %rax Loads the effective address of the current instruction pointer to %rsi Moves the value at %rax to %rdi Calls a function located at 1cd with %rdi and %rsi as the 1 st and 2 nd arguments Moves %eax (the value returned by the previous function call) to -0x44(%rbp) Compares the value of 0 to the value at -0x44(%rbp) If it is not equal jump to 1dd otherwise run the indented instruction Moves a value of 2 to %ebx Loads the effective address of -0x40(%rbp) to %rax Moves the value at %rax to %rdi Calls the function located at 1ee Moves the value at %ebx to %eax Moves the value at -0x18(%rbp) to %rcx Xors the value at %fs:0x28 with the value at %rcx If they are equal (both zero) jump to 23a (it should since the register or data segment were not modified) Otherwise it will jump to 235 **(Meaning code before 23a will be skipped) 8

Assembly Code Block Explanation of Functionality 21b: mov %rax,%rbx 21e: lea -0x40(%rbp),%rax 222: mov %rax,%rdi 225: callq 22a <_Z25CheckUserPermissionAccessv+0x10a> 22a: mov %rbx,%rax 22d: mov %rax,%rdi 230: callq 235 <_Z25CheckUserPermissionAccessv+0x115> 235: callq 23a <_Z25CheckUserPermissionAccessv+0x11a> 23a: add $0x48,%rsp 23e: pop %rbx 23f: pop %rbp 240: retq Will call the function located at 23a if the data at %fs:0x28 does not match %rcx (it should not run) Adds 0x48 to the stack pointer effectively deallocating those bytes Pops %rbx off the stack Returns the function DisplayInfo Function Assembly Code Block Explanation of Functionality 241: push %rbp 242: mov %rsp,%rbp 245: lea 0x0(%rip),%rsi # 24c <_Z11DisplayInfov+0xb> 24c: lea 0x0(%rip),%rdi # 253 <_Z11DisplayInfov+0x12> 253: callq 258 <_Z11DisplayInfov+0x17> 258: mov %rax,%rdx 25b: mov 0x0(%rip),%rax # 262 Pushes the base pointer to the stack Moves the stack pointer to the base pointer. Loads the current address of the instruction pointer to %rsi Loads the current address of the instruction pointer to %rdi Calls a function located at 258 with %rdi and %rsi as the 1 st and 2 nd arguments Moves %rax (the value of the previous function call) to %rdx Moves the current value of the instruction pointer to %rax Moves the value at %rax to %rsi Moves the value at %rdx to %rdi 10

Assembly Code Block Explanation of Functionality <_Z11DisplayInfov+0x21> 262: mov %rax,%rsi 265: mov %rdx,%rdi 268: callq 26d <_Z11DisplayInfov+0x2c> 26d: lea 0x0(%rip),%rsi # 274 <_Z11DisplayInfov+0x33> 274: lea 0x0(%rip),%rdi # 27b <_Z11DisplayInfov+0x3a> 27b: callq 280 <_Z11DisplayInfov+0x3f> 280: lea 0x0(%rip),%rsi # 287 <_Z11DisplayInfov+0x46> 287: mov %rax,%rdi 28a: callq 28f <_Z11DisplayInfov+0x4e> 28f: lea 0x0(%rip),%rsi # 296 <_Z11DisplayInfov+0x55> 296: mov %rax,%rdi 299: callq 29e <_Z11DisplayInfov+0x5d> 29e: mov %rax,%rdx 2a1: mov 0x0(%rip),%eax # 2a7 <_Z11DisplayInfov+0x66> 2a7: mov %eax,%esi 2a9: mov %rdx,%rdi 2ac: callq 2b1 <_Z11DisplayInfov+0x70> 2b1: mov %rax,%rdx 2b4: mov 0x0(%rip),%rax # 2bb <_Z11DisplayInfov+0x7a> Calls a function located at 26d with %rdi and %rsi as the 1 st and 2 nd argument. Loads the effective address of the current instruction pointer to %rsi Loads the effective address of the current instruction pointer to %rdi Calls a function located at 280 with %rdi and %rsi as the 1 st and 2 nd arguments Loads the current address of the instruction pointer to %rsi Moves the value at %rax (the value of the previous function call) to %rdi Calls a function located at 28f with %rdi and %rsi as the 1 st and 2 nd arguments Loads the address of instruction pointer to %rsi Moves the value at %rax (the value of the previous function call) to %rdi Calls a function located at 29e with %rdi and %rsi as the 1 st and 2 nd arguments Moves the value at %rax (the value of the previous function call) to %rdx Moves the current value of the instruction pointer to %eax Moves the value at %eax to %esi Moves the value at %rxs to %rdi Calls a function located at 2b1 with %rdi and %rsi as the 1 st and 2 nd arguments Moves the value at %rax (the value of the previous function call) to %rdx Moves the current value of the instruction pointer to %rax Moves the value at %rax to %rsi Moves the value at %rdx to %rdi Calls the function located at 2c6 with %rdi and %rsi as the 1 st and 2 nd function Loads the current address of the instruction pointer to %rsi Loads the current address of the instruction pointer to %rdi Calls the function located at 2d9 with %rdi and %rsi as the 1 st and 2 nd function Loads the current address of the instruction pointer to %rsi Moves %rax (the result of the previous function call) to %rdi Calls a function located at 2e8 with %rdi and %rsi as 11

Assembly Code Block Explanation of Functionality 317: mov %rdx,%rdi 31a: callq 31f <_Z11DisplayInfov+0xde> 31f: lea 0x0(%rip),%rsi # 326 <_Z11DisplayInfov+0xe5> 326: lea 0x0(%rip),%rdi # 32d <_Z11DisplayInfov+0xec> 32d: callq 332 <_Z11DisplayInfov+0xf1> 332: lea 0x0(%rip),%rsi # 339 <_Z11DisplayInfov+0xf8> 339: mov %rax,%rdi 33c: callq 341 <_Z11DisplayInfov+0x100> 341: lea 0x0(%rip),%rsi # 348 <_Z11DisplayInfov+0x107> 348: mov %rax,%rdi 34b: callq 350 <_Z11DisplayInfov+0x10f> 350: mov %rax,%rdx 353: mov 0x0(%rip),%eax # 359 <_Z11DisplayInfov+0x118> 359: mov %eax,%esi 35b: mov %rdx,%rdi 35e: callq 363 <_Z11DisplayInfov+0x122> 363: mov %rax,%rdx 366: mov 0x0(%rip),%rax # 36d <_Z11DisplayInfov+0x12c> 36d: mov %rax,%rsi 370: mov %rdx,%rdi Loads the current address of the instruction pointer to %rsi Moves %rax (the result of the previous function call) to %rdi Calls a function located at 350 with %rdi and %rsi as the 1 st and 2 nd arguments Moves %rax (the result of the previous function call) to %rdx Moves the current value of the instruction pointer to %eax Moves the value at %eax to %esi Moves the value at %rdx (the value of the previous function call) to %rdi Calls a function located at 363 with %rdi and %esi as the 1 st and 2 nd arguments Moves %rax (the result of the previous function call) to %rdx Moves the current value of the instruction pointer to %rax Moves the value at %rax to %rsi Moves the value at %rdx (the result of the previous function call) to %rdi Calls a function located at 378 with %rdi and %rsi as the 1 st and 2 nd arguments 13

Assembly Code Block Explanation of Functionality 373: callq 378 <_Z11DisplayInfov+0x137> 378: lea 0x0(%rip),%rsi # 37f <_Z11DisplayInfov+0x13e> 37f: lea 0x0(%rip),%rdi # 386 <_Z11DisplayInfov+0x145> 386: callq 38b <_Z11DisplayInfov+0x14a> 38b: lea 0x0(%rip),%rsi # 392 <_Z11DisplayInfov+0x151> 392: mov %rax,%rdi 395: callq 39a <_Z11DisplayInfov+0x159> 39a: lea 0x0(%rip),%rsi # 3a1 <_Z11DisplayInfov+0x160> 3a1: mov %rax,%rdi 3a4: callq 3a9 <_Z11DisplayInfov+0x168> 3a9: mov %rax,%rdx 3ac: mov 0x0(%rip),%eax # 3b2 <_Z11DisplayInfov+0x171> 3b2: mov %eax,%esi 3b4: mov %rdx,%rdi 3b7: callq 3bc <_Z11DisplayInfov+0x17b> 3bc: mov %rax,%rdx 3bf: mov 0x0(%rip),%rax # 3c6 <_Z11DisplayInfov+0x185> 3c6: mov %rax,%rsi c9: mov %rdx,%rdi 3cc: callq 3d1 <_Z11DisplayInfov+0x190> Loads the current address of the instruction pointer to %rsi Loads the current address of the instruction pointer to %rdi Calls a function located 38b with %rdi and %rsi as the 1 st and 2 nd arguments Moves %rax (the result of the previous function call) to %rdi Calls a function located 38b with %rdi as the 1 st argument Loads the current value of the instruction pointer to %rsi Move %rax (the result of the previous function call) to %rdi Calls a function located at 39a with %rdi and %rsi as the 1 st and 2 nd arguments Loads the current address of the instruction pointer to %rsi Move %rax (the result of the previous function call) to %rdi Calls a function located at 39a with %rdi and %rsi as the 1 st and 2 nd arguments Move %rax (the result of the previous function call) to %rdx Moves the current value of the instruction pointer to %rax Moves the value at %rax to %rsi Moves the value at %rdx (the result of the previous function call) to %rdi Calls a function located at 3d1 with %rdi and %rsi as the 1 st and 2 nd arguments 14

Assembly Code Block Explanation of Functionality 42b: pop %rbp 42c: retq 16