Hi, I have a small question about assembler code generated by gcc:
when I compile the trivial program main () {} with gcc -O0 I get the
following lines
pushl %ebp
movl %esp, %ebp
subl $8, %esp
andl $-16, %esp
which are very clear. But also the following lines:
movl $0, %eax
addl $15, %eax
addl $15, %eax
shrl $4, %eax
sall $4, %eax
subl %eax, %esp
of which I understand the semantics individually, but I don't see
what are needed for. Why put 0 into %eax and then add 15 and again
add 15?
Could you tell me what is going on? Or point me to documentation or
to a knowledgeable person?
Thanks in advance!!
Yannis
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