string - Access data on the stack -

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i'm planning write program in assembly searches substring in string , writes words contain substring. example:

string: "adgfh asdsd zxc dbasdas"

substring: "as"

output: "asdsd dbasdas"

the idea use 1 register (dx) , stack store data. i'm pushing string , substring stack. main question - possible access data under top element in stack without popping data? want use dx remember spaces between words , compare each letter in string 1st letter in string, , if it's same letter increment pointer in both string , substring point @ next letter in words , redo comparing...etc.

yes, can access items on stack because stack memory. if in 16 bit mode, can not use dx that, need bx, si, di or bp. example:

mov bx, sp mov bl, ss:[bx+10]

note need ss segment override except bp. in 32 bit mode can use esp directly, such as:

mov dl, [esp+10]

ps: that's strange project first program ;)


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