> On Sunday 17 October 2004 12:26 pm, Wouter van Ooijen wrote:
>> > if (foo == 3) {
>> >
>> > would collect "foo" and subtract the #3 to test for zero
>> >
>> > if (3 == foo) {
>> >
>> > would collect 3, place it on the stack, then collect foo,
>> > then subtract foo from stack value "3"
>>
>> stack??
>
> ...just thinking-out-loud that C is supposed to be cross-platform.  ;-)
>
> C is usually analyzed from left to right.
> If you wish to speak PIC, you could say a fictional compiler creates 
> this....
> if (foo == 3) {
> movfw foo
> xorlw 3
> skpz
> goto endif
> ;do "if" here
>
> if (3 == foo) {
> movlw 3
> movwf scratchpad_temp
> movfw foo
> xorlw scratchpad_temp
> skpz
> goto endif
> ;do "if" here
>

Why wouldn't the compiler just generate:

movlw 3
xorwf  foo,w
skpz
goto endif


Bob Ammerman
RAm Systems

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