Re: [9front] [PATCH] silence drawterm runestrchr while(assign) warning

[ori@eigenstate.org]

Quoth Amavect <amavect@gmail.com>:
> Hi,
> 
> I want to shut up drawterm compile warnings without resorting to -Wno.
> I'll rationalize this with reducing function sizes by bytes,
> "improving readability", and micro optimizations for kencc.
> 
> Here are some basic transformations on strchr and runestrchr.
> It reduces 9front function byte sizes on the arches I tested
> (amd64 0x4f->0x43, arm 0x50->0x40, power 0x68->0x5c).
> It shuts up a gcc warning about runestrchr while(c1 = *s++)
> (when compiled without -Wno-parentheses)
> Attached are patches for 9front and drawterm.
> Below are the full functions for criticism.

Looks fine to me, thanks.

Committed locally, will push tomorrow after I take a second,
well rested look.

Will also toss your unit tests into the regress test repo.

> Thanks,
> Amavect
> 
> 
> char*
> strchr(char *s, int c)
> {
> 	char r;
> 
> 	if(c == 0)
> 		while(*s++)
> 			;
> 	else
> 		while((r = *s++) != c)
> 			if(r == 0)
> 				return 0;
> 	return s-1;
> }
> 
> 
> Rune*
> runestrchr(Rune *s, Rune c)
> {
> 	Rune r;
> 
> 	if(c == 0)
> 		while(*s++)
> 			;
> 	else
> 		while((r = *s++) != c)
> 			if(r == 0)
> 				return 0;
> 	return s-1;
> }
> 
> 
> unit test:
> 
> #include <u.h>
> #include <libc.h>
> 
> void
> main(void)
> {
> 	char *v = "foo bar ss";
> 	char *e;
> 	Rune *c = L"foo βαρ ß";
> 	Rune *t;
> 
> 	e = strchr(v, L'z');
> 	assert(e == nil);
> 	e = strchr(v, L'a');
> 	assert(e == v+5);
> 	e = strchr(v, 0);
> 	assert(e == v+10);
> 
> 	t = runestrchr(c, L'z');
> 	assert(t == nil);
> 	t = runestrchr(c, L'α');
> 	assert(t == c+5);
> 	t = runestrchr(c, 0);
> 	assert(t == c+9);
> }
>