Re: [ANN] Lua 5.3.0 (rc4) now available

[Tim Hill <drtimhill@...>]

> On Jan 13, 2015, at 12:15 AM, Paige DePol <lual@serfnet.org> wrote:
> 
> Tim Hill <drtimhill@gmail.com> wrote:
>> However, as Lua does little (if any) constant folding at compile time, this will be more expensive than the equivalent hex/decimal literal.
>> 
>> —Tim
> 
> Lua does constant folding... grep the codebase for 'folding'! 
> 
> "a = 1 << 5"
> 
> Compiles to:
> 
> main <ackoop:0,0> (2 instructions at 0x7f8db8405270)
> 0+ params, 2 slots, 1 upvalue, 0 locals, 2 constants, 0 functions
> 	1	[2]	SETTABUP 	0 -1 -2	; _ENV "a" 32
> 	2	[2]	RETURN   	0 1
> constants (2) for 0x7f8db8405270:
> 	1	"a"
> 	2	32
> locals (0) for 0x7f8db8405270:
> upvalues (1) for 0x7f8db8405270:
> 	0	_ENV	1	0
> 
> Looks like it folded "1 << 5" to "32" correctly! :)
> 
> ~pmd
> 
> 

I stand corrected, thank you.

—Tim