Can we say that in Pascal the result of:
E1 shl E2
is of same type as E1 ?
(so if E1 is LongWord then result is LongWord also?)
What if there is an expression on left side:
(E1*x) shl E2
Will E1*x promote to 64 bits (on 64 bit target)?
-Laco.
Hello *,
I have code in C like this:
E1 << E2
If E1 is of unsigned type then "The value of E1 << E2 is E1
left-shifted E2 bit positions; vacated bits are zero-filled. If E1 has
an unsigned type, the value of the result is E1 × 2^E2, reduced modulo
one more than the maximum value representable in the result type."
I understand this as result of such operation does not grow over 32
bits, right?
In Pascal I have:
E1 shl E2
where E1 is of LongWord type.
On 64-bit target this result of shl can overcome 32 bits (iow operates
on 32 bits)?
(does also bit shift operations works on 64 bits or this only affect
arithmetic operations like multiply?)
Assembler suggests that shl works on 32 bits: shl %cl,%r11d
-Laco.
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