Eric Gallager <eg...@gwmail.gwu.edu> writes:
> On Tue, Jul 23, 2024 at 10:07 AM Sam James <s...@gentoo.org> wrote:
>>
>> At -O1, the intention is that we compile things in a "reasonable" amount
>> of time (ditto memory use). In particular, we try to especially avoid
>> optimizations which scale poorly on pathological cases, as is the case
>> for large machine-generated code.
>>
>> Recommend -O1 for large machine-generated code, as has been informally
>> done on bugs for a while now.
>>
>> This applies (broadly speaking) for both large machine-generated functions
>> but also to a lesser extent repetitive small-but-still-not-tiny functions
>> from a generator program.
>>
>> gcc/ChangeLog:
>> PR middle-end/114855
>> * doc/invoke.texi (Optimize options): Mention machine-generated
>> code for -O1.
>> ---
>> richi, does this accurately reflect the discussion we had on IRC a little
>> while ago?
>>
>> Please push if OK, thanks.
>>
>> gcc/doc/invoke.texi | 5 +++++
>> 1 file changed, 5 insertions(+)
>>
>> diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
>> index e0a641213ae4..9fb0925ed292 100644
>> --- a/gcc/doc/invoke.texi
>> +++ b/gcc/doc/invoke.texi
>> @@ -12560,6 +12560,11 @@ With @option{-O}, the compiler tries to reduce code
>> size and execution
>> time, without performing any optimizations that take a great deal of
>> compilation time.
>>
>> +@option{-O} is the recommended optimization level for large
>> machine-generated
>> +code as a sensible balance between time taken to compile and memory use:
>> +higher optimization levels perform optimizations with greater algorithmic
>> +complexity than at @option{-O}.
>> +
>
> Personally, I get confused when "-O1" is written as just "-O"...
I, too, prefer -O1, but I was trying to be good and stick to
convention. But then I did -O1 in the commit message.
If people are fine with it, I'd prefer to do -O1.
thanks,
sam
