On Friday 25 February 2005 20:31, .jareeN. wrote: > Hi all, Hello. > I am using gcc -S to generate this assembly code. The compiler > gives: > > andl $-16, %esp > > I understand that we are here basically anding 0xffff00ff with %esp. But -16 equals 0xfffffff0, not 0xffff00ff. So, by ANDing %esp with 0xfffffff0, you're actually aligning it to a 16-byte boundary and, as the code you've posted seems to be setting up a stack frame, this is no problem, since the value of %esp will only decrease. > what I can't get is use of doing this. Could somebody tell me the > significance of doing this. > > > > Detailed code: > > pushl %ebp > movl $16, %edx > movl %esp, %ebp > subl $8, %esp > andl $-16, %esp > movl %edx, 4(%esp) > > > TIA
