Re: [PATCH] tcg: refactor pool data for simplicity and comprehension

[Richard Henderson <richard.henderson@linaro.org>]

On 2/15/25 12:24, Michael Clark wrote:
>> Why?  varargs generally produces horrible code.
>> The split between alloc and insert was intentional to avoid this.
> 
> it's pretty good code on SysV because it goes via registers except for perhaps new_pool_l8 
> which will spill to stack and get copied unless the inliner can eliminate the copies. 
> maybe windows has bad varargs. but I like the style better than deeper layers of wrapper 
> functions. they should fix the compiler so that it produces better code.

varargs will generally prevent inlining.

Indeed, just a quick look at aarch64 tcg_out_movi shows that without your change, 
new_pool_label, new_pool_data and new_pool_insert are all inlined.  With your change, 
new_pool_data is not inlined, all the argument regs are dumped to the stack, etc.

I don't think this is a good change to make.


r~