Hi
in this program test function has a known return value , and should be
calculated in compile time , but fpc make it in real time !!!
---------------------
program test;
var c : int32;
function test( p: int32): int32; inline;
var i : int32;
begin
i := p;
test := i+2+c+2+c+2+c;
end;
begin
c:= test(128);
end.
---------------------
fpc (3.1.1 i386 ) generate this asm
---------------------
_main:
call FPC_INITIALIZEUNITS
movl $128,%eax
movl U_$P$TEST_$$_C,%eax
addl $130,%eax
addl $2,%eax
addl U_$P$TEST_$$_C,%eax
addl $2,%eax
addl U_$P$TEST_$$_C,%eax
movl %eax,U_$P$TEST_$$_C
call FPC_DO_EXIT
ret
----------------------
while the same program in c compiled with old version of gcc generate this asm
which is optimal
------------------------
_main:
pushl %ebp
movl %esp, %ebp
andl $-16, %esp
call ___main
movl _c, %eax
leal 134(%eax,%eax,2), %eax
movl %eax, _c
leave
ret
-----------------------
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