So, after another week of studying assembly, I went back and rewrote my bubble sort algorithm. \u00a0I’m feeling a lot better about this implementation. \u00a0I’m sure it could could be even better, but I’m pretty pleased with it this time.<\/p>\n
Here is the code:<\/p>\n
<\/p>\n
; Author J. Logiodice
\n; Date: 05\/28\/2016
\n; Purpose: Bubble SOrt
\n; This method will read in a series of TOTAL_NUMS numbers
\n; And bubble sort them, then print them out in sorted order to the screen
\nformat PE console
\nentry start<\/p>\n
include ‘win32a.inc’<\/p>\n
TOTAL_NUMS = 10 ;10<\/p>\n
section ‘.bss’ data readable writeable<\/p>\n
array_numbers dd TOTAL_NUMS dup (?)
\nnMinus1Mem dd ?
\nboolSwapped db ?<\/p>\n
section ‘.text’ code readable executable<\/p>\n
start:<\/p>\n
; Set up the loop variables
\nmov ecx, dword TOTAL_NUMS
\nmov esi, dword TOTAL_NUMS ;ecx
\n; +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
\n; Read in one number at a time, for TOTAL_NUMS numbers, store them in the bytes that
\n; start with array_numbers
\n; +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++<\/p>\n
loopRead:<\/p>\n
; have to use esi because read_hex uses edi
\ndec esi<\/p>\n
; read input into eax but first clear out eax
\nxor eax, eax
\ncall read_hex<\/p>\n
; move value into memory offset (reverse order)
\nmov dword [array_numbers + esi * 4], eax<\/p>\n
loop loopRead<\/p>\n
; +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
\n; loop iteratively over the array until no more swapping occurs,
\n; and the highest number ends up in the lowest part of the array (lowest to highest)
\n; start with array_numbers
\n; +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
\n; Set back up the loop variables
\nrestartLoop:<\/p>\n
mov ecx, dword TOTAL_NUMS – 1
\n; set the swapped variable to false
\nmov [boolSwapped], byte 0 ;dword 0<\/p>\n
lea esi, [array_numbers]<\/p>\n
loopSort:<\/p>\n
; jump to the loop exit if ecx is 0
\n; this will occur if we are at the end of the counter, or if the
\n; initial array was of size 0 bytes
\njecxz loopExit
\n; load the first number in array_numbers into eax
\nlodsd
\n; after lodsd, edi is pointing to edi – dword
\n; if we compare the value at edi at this point it is effectively the value below eax
\n; compare eax to the number below it in the array
\ncmp eax, [esi] ;, eax
\n; if [esi] > eax, then no ZF or CF set, so jump below or equal
\njbe noSwap
\n; if here then eax is lower, swap eax and the higher number in memory
\nmov ebx, dword [esi]
\nmov [esi], dword eax
\nmov dword [esi-4], ebx<\/p>\n
; if a swap occured, set boolSwapped = 1<\/p>\n
mov [boolSwapped], 1b
\nnoSwap:
\n; jump here if no swapping needs to occur, but we’re still in the loop
\nloop loopSort<\/p>\n
loopExit:<\/p>\n
; if boolSwapped isn’t false, then we’ve swapped at least one
\n; during the iteration, let’s go through it one more time to make sure
\n; that we don’t have any more to swap
\ncmp [boolSwapped], 1b
\njae restartLoop
\n; +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
\n; Print each number back out to the screen for unmodified numbers
\n; we will loop from the lowest to highest part of the array – which is the largest to smallest number
\n; +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++<\/p>\n
mov ecx, TOTAL_NUMS
\nlea esi, [array_numbers]<\/p>\n
loopPrint:<\/p>\n
jecxz loopExit
\nlodsd
\ncall print_eax<\/p>\n
loop loopPrint
\nexit_prog:
\npush 0
\ncall [ExitProcess]
\ninclude ‘training.inc’<\/p>\n","protected":false},"excerpt":{"rendered":"
So, after another week of studying assembly, I went back and rewrote my bubble sort algorithm. \u00a0I’m feeling a lot better about this implementation. \u00a0I’m sure it could could be even better, but I’m pretty pleased with it this time. Here is the code: ; Author J. Logiodice ; Date: 05\/28\/2016 ; Purpose: Bubble … Continue reading “Updated Bubble Sort in x86 ASM”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":579,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-576","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"jetpack_featured_media_url":"https:\/\/darthjedi.logiodice.com\/wp-content\/uploads\/2016\/05\/assembly2.jpg","jetpack_sharing_enabled":true,"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/darthjedi.logiodice.com\/index.php?rest_route=\/wp\/v2\/posts\/576","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/darthjedi.logiodice.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/darthjedi.logiodice.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/darthjedi.logiodice.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/darthjedi.logiodice.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=576"}],"version-history":[{"count":1,"href":"https:\/\/darthjedi.logiodice.com\/index.php?rest_route=\/wp\/v2\/posts\/576\/revisions"}],"predecessor-version":[{"id":577,"href":"https:\/\/darthjedi.logiodice.com\/index.php?rest_route=\/wp\/v2\/posts\/576\/revisions\/577"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/darthjedi.logiodice.com\/index.php?rest_route=\/wp\/v2\/media\/579"}],"wp:attachment":[{"href":"https:\/\/darthjedi.logiodice.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=576"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/darthjedi.logiodice.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=576"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/darthjedi.logiodice.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=576"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}