# Comparing arrays of numbers. == code array-equal?: # a: (addr array int), b: (addr array int) -> result/eax: boolean # pseudocode: # asize = a->size # if (asize != b->size) return false # i = 0 # curra = a->data # currb = b->data # while i < asize # i1 = *curra # i2 = *currb # if (c1 != c2) return false # i+=4, curra+=4, currb+=4 # return true # # registers: # i: ecx # asize: edx # curra: esi # currb: edi # i1: eax # i2: ebx # # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # . save registers 51/push-ecx 52/push-edx 53/push-ebx 56/push-esi 57/push-edi # esi = a 8b/-> *(ebp+8) 6/r32/esi # edi = b 8b/-> *(ebp+0xc) 7/r32/edi # var asize/edx: int = a->size 8b/-> *esi 2/r32/edx $array-equal?:sizes: # if (asize != b->size) return false 39/compare *edi 2/r32/edx 75/jump-if-!= $array-equal?:false/disp8 # var curra/esi: (addr byte) = a->data 81 0/subop/add %esi 4/imm32 # var currb/edi: (addr byte) = b->data 81 0/subop/add %edi 4/imm32 # var i/ecx: int = 0 31/xor-with %ecx 1/r32/ecx # var vala/eax: int # var valb/ebx: int $array-equal?:loop: # if (i >= asize) return true 39/compare %ecx 2/r32/edx 7d/jump-if->= $array-equal?:true/disp8 # var vala/eax: int = *curra 8b/-> *esi 0/r32/eax # var valb/ebx: int = *currb 8b/-> *edi 3/r32/ebx # if (vala != valb) return false 39/compare %eax 3/r32/ebx 75/jump-if-!= $array-equal?:false/disp8 # i += 4 81 0/subop/add %ecx 4/imm32 # currs += 4 81 0/subop/add %esi 4/imm32 # currb += 4 81 0/subop/add %edi 4/imm32 eb/jump $array-equal?:loop/disp8 $array-equal?:true: b8/copy-to-eax 1/imm32 eb/jump $array-equal?:end/disp8 $array-equal?:false: b8/copy-to-eax 0/imm32 $array-equal?:end: # . restore registers 5f/pop-to-edi 5e/pop-to-esi 5b/pop-to-ebx 5a/pop-to-edx 59/pop-to-ecx # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return test-compare-empty-with-empty-array: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # var ecx: (array _) = [] 68/push 0/imm32/size 89/<- %ecx 4/r32/esp # var edx: (array _) = [] 68/push 0/imm32/size 89/<- %edx 4/r32/esp # (array-equal? %ecx %edx) # => eax (check-ints-equal %eax 1 "F - test-compare-empty-with-empty-array") # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return test-compare-empty-with-non-empty-array: # also checks size-mismatch code path # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # var ecx: (array int) = [1] 68/push 1/imm32 68/push 4/imm32/size 89/<- %ecx 4/r32/esp # var edx: (array int) = [] 68/push 0/imm32/size 89/<- %edx 4/r32/esp # (array-equal? %ecx %edx) # => eax (check-ints-equal %eax 0 "F - test-compare-empty-with-non-empty-array") # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return test-compare-equal-arrays: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # var ecx: (array int) = [1, 2, 3] 68/push 3/imm32 68/push 2/imm32 68/push 1/imm32 68/push 0xc/imm32/size 89/<- %ecx 4/r32/esp # var edx: (array int) = [1, 2, 3] 68/push 3/imm32 68/push 2/imm32 68/push 1/imm32 68/push 0xc/imm32/size 89/<- %edx 4/r32/esp # (array-equal? %ecx %edx) # => eax (check-ints-equal %eax 1 "F - test-compare-equal-arrays") # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return test-compare-inequal-arrays-equal-sizes: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # var ecx: (array int) = [1, 4, 3] 68/push 3/imm32 68/push 4/imm32 68/push 1/imm32 68/push 0xc/imm32/size 89/<- %ecx 4/r32/esp # var edx: (array int) = [1, 2, 3] 68/push 3/imm32 68/push 2/imm32 68/push 1/imm32 68/push 0xc/imm32/size 89/<- %edx 4/r32/esp # (array-equal? %ecx %edx) # => eax (check-ints-equal %eax 0 "F - test-compare-inequal-arrays-equal-sizes") # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return _parse-array-of-ints: # ad: (addr allocation-descriptor), s: (addr array byte), out: (addr handle array int) # pseudocode # end = &s->data[s->size] # curr = s->data # size = 0 # while true # if (curr >= end) break # curr = skip-chars-matching-in-slice(curr, end, ' ') # if (curr >= end) break # curr = skip-chars-not-matching-in-slice(curr, end, ' ') # ++size # allocate-array(ad, size*4, out) # var slice: slice = {s->data, 0} # curr = lookup(out)->data # while true # if (slice->start >= end) break # slice->start = skip-chars-matching-in-slice(slice->start, end, ' ') # if (slice->start >= end) break # slice->end = skip-chars-not-matching-in-slice(slice->start, end, ' ') # *curr = parse-hex-int-from-slice(slice) # curr += 4 # slice->start = slice->end # return result # # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # . save registers 50/push-eax 51/push-ecx 52/push-edx 53/push-ebx 56/push-esi 57/push-edi # esi = s 8b/-> *(ebp+0xc) 6/r32/esi # var curr/ecx: (addr byte) = s->data 8d/copy-address *(esi+4) 1/r32/ecx # var end/edx: (addr byte) = &s->data[s->size] # . edx = s->size 8b/-> *esi 2/r32/edx # . edx += curr 01/add-to %edx 1/r32/ecx # var size/ebx: int = 0 31/xor-with %ebx 3/r32/ebx $_parse-array-of-ints:loop1: # if (curr >= end) break 39/compare %ecx 2/r32/edx 73/jump-if-addr>= $_parse-array-of-ints:break1/disp8 # curr = skip-chars-matching-in-slice(curr, end, ' ') (skip-chars-matching-in-slice %ecx %edx 0x20) # => eax 89/<- %ecx 0/r32/eax # if (curr >= end) break 39/compare %ecx 2/r32/edx 73/jump-if-addr>= $_parse-array-of-ints:break1/disp8 # curr = skip-chars-not-matching-in-slice(curr, end, ' ') (skip-chars-not-matching-in-slice %ecx %edx 0x20) # => eax 89/<- %ecx 0/r32/eax # size += 4 81 0/subop/add %ebx 4/imm32 eb/jump $_parse-array-of-ints:loop1/disp8 $_parse-array-of-ints:break1: (allocate-array *(ebp+8) %ebx *(ebp+0x10)) $_parse-array-of-ints:pass2: # var slice/edi: slice = {s->data, 0} 68/push 0/imm32/end 8d/copy-address *(esi+4) 7/r32/edi 57/push-edi 89/<- %edi 4/r32/esp # curr = lookup(out)->data 8b/-> *(ebp+0x10) 0/r32/eax (lookup *eax *(eax+4)) # => eax 8d/copy-address *(eax+4) 1/r32/ecx $_parse-array-of-ints:loop2: # if (slice->start >= end) break 39/compare *edi 2/r32/edx 73/jump-if-addr>= $_parse-array-of-ints:end/disp8 # slice->start = skip-chars-matching-in-slice(slice->start, end, ' ') (skip-chars-matching-in-slice *edi %edx 0x20) # => eax 89/<- *edi 0/r32/eax # if (slice->start >= end) break 39/compare *edi 2/r32/edx 73/jump-if-addr>= $_parse-array-of-ints:end/disp8 # slice->end = skip-chars-not-matching-in-slice(slice->start, end, ' ') (skip-chars-not-matching-in-slice *edi %edx 0x20) # => eax 89/<- *(edi+4) 0/r32/eax # *curr = parse-hex-int-from-slice(slice) (parse-hex-int-from-slice %edi) 89/<- *ecx 0/r32/eax # curr += 4 81 0/subop/add %ecx 4/imm32 # slice->start = slice->end 8b/-> *(edi+4) 0/r32/eax 89/<- *edi 0/r32/eax eb/jump $_parse-array-of-ints:loop2/disp8 $_parse-array-of-ints:end: # . reclaim locals 81 0/subop/add %esp 8/imm32 # . restore registers 5f/pop-to-edi 5e/pop-to-esi 5b/pop-to-ebx 5a/pop-to-edx 59/pop-to-ecx 58/pop-to-eax # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return test-parse-array-of-ints: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # var h/esi: (handle array int) 68/push 0/imm32 68/push 0/imm32 89/<- %esi 4/r32/esp # var ecx: (array int) = [1, 2, 3] 68/push 3/imm32 68/push 2/imm32 68/push 1/imm32 68/push 0xc/imm32/size 89/<- %ecx 4/r32/esp # (_parse-array-of-ints Heap "1 2 3" %esi) (lookup *esi *(esi+4)) # => eax (array-equal? %ecx %eax) # => eax (check-ints-equal %eax 1 "F - test-parse-array-of-ints") # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return test-parse-array-of-ints-empty: # - empty string = empty array # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # var h/esi: handle 68/push 0/imm32 68/push 0/imm32 89/<- %esi 4/r32/esp # (_parse-array-of-ints Heap "" %esi) (lookup *esi *(esi+4)) # => eax (check-ints-equal *eax 0 "F - test-parse-array-of-ints-empty") # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return test-parse-array-of-ints-just-whitespace: # - just whitespace = empty array # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # var h/esi: handle 68/push 0/imm32 68/push 0/imm32 89/<- %esi 4/r32/esp # (_parse-array-of-ints Heap Space %esi) (lookup *esi *(esi+4)) # => eax (check-ints-equal *eax 0 "F - test-parse-array-of-ints-just-whitespace") # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return test-parse-array-of-ints-extra-whitespace: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # var h/esi: handle 68/push 0/imm32 68/push 0/imm32 89/<- %esi 4/r32/esp # var ecx: (array int) = [1, 2, 3] 68/push 3/imm32 68/push 2/imm32 68/push 1/imm32 68/push 0xc/imm32/size 89/<- %ecx 4/r32/esp # (_parse-array-of-ints Heap " 1 2 3 " %esi) (lookup *esi *(esi+4)) # => eax (array-equal? %ecx %eax) # => eax (check-ints-equal %eax 1 "F - test-parse-array-of-ints-extra-whitespace") # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return parse-array-of-ints: # s: (addr array byte), out: (addr handle array int) # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # (_parse-array-of-ints Heap *(ebp+8) *(ebp+0xc)) $parse-array-of-ints:end: # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return # helper for later tests # compare an array with a string representation of an array literal check-array-equal: # a: (addr array int), expected: (addr string), msg: (addr string) # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # . save registers 50/push-eax 56/push-esi # var h/esi: handle 68/push 0/imm32 68/push 0/imm32 89/<- %esi 4/r32/esp # var b/eax: (addr array int) = parse-array-of-ints(Heap, expected) (parse-array-of-ints *(ebp+0xc) %esi) (lookup *esi *(esi+4)) # => eax # (array-equal? *(ebp+8) %eax) (check-ints-equal %eax 1 *(ebp+0x10)) $check-array-equal:end: # . restore registers 5e/pop-to-esi 58/pop-to-eax # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return test-check-array-equal: # . prologue 55/push-ebp 89/<- %ebp 4/r32/esp # var ecx: (array int) = [1, 2, 3] 68/push 3/imm32 68/push 2/imm32 68/push 1/imm32 68/push 0xc/imm32/size 89/<- %ecx 4/r32/esp # (check-array-equal %ecx "1 2 3" "F - test-check-array-equal") # . epilogue 89/<- %esp 5/r32/ebp 5d/pop-to-ebp c3/return == data # length-prefixed string containing just a single space Space: # (array byte) # size: int 1/imm32 # data 20/space