https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108540
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2023-01-25
CC| |aldyh at gcc dot gnu.org,
| |amacleod at redhat dot com
Target Milestone|--- |13.0
Ever confirmed|0 |1
Priority|P3 |P1
--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
stdarg.h isn't needed, so:
__attribute__((noipa)) void
bar (const char *cp, unsigned long size, char sign, int dsgn)
{
if (__builtin_strcmp (cp, "ZERO") != 0 || size != 4 || sign != '-' || dsgn !=
1)
__builtin_abort ();
}
__attribute__((noipa)) void
foo (int x, int ch, double d)
{
const char *cp = "";
unsigned long size = 0;
char sign = '\0';
switch (x)
{
case 42:
if (__builtin_isinf (d))
{
if (d < 0)
sign = '-';
cp = "Inf";
size = 3;
break;
}
if (__builtin_isnan (d))
{
cp = "NaN";
size = 3;
break;
}
if (d < 0)
{
d = -d;
sign = '-';
}
else if (d == 0.0 && __builtin_signbit (d))
sign = '-';
else
sign = '\0';
if (ch == 'a' || ch == 'A')
{
union U { long long l; double d; } u;
int dsgn;
u.d = d;
if (u.l < 0)
{
dsgn = 1;
u.l &= 0x7fffffffffffffffLL;
}
else
dsgn = 0;
if (__builtin_isinf (d))
{
cp = "INF";
size = 3;
}
else if (__builtin_isnan (d))
{
cp = "NAN";
size = 3;
}
else if (d == 0)
{
cp = "ZERO";
size = 4;
}
else
{
cp = "WRONG";
size = 5;
}
bar (cp, size, sign, dsgn);
}
}
}
int
main ()
{
foo (42, 'a', -0.0);
return 0;
}
The testcase is hand-written from what I see in
https://github.com/ruby/ruby/blob/a528908271c678360d2d8ca232c178e7cdd340b4/vsnprintf.c#L529
https://github.com/ruby/ruby/blob/a528908271c678360d2d8ca232c178e7cdd340b4/vsnprintf.c#L1229
https://github.com/ruby/ruby/blob/a528908271c678360d2d8ca232c178e7cdd340b4/missing/dtoa.c#L3387
where hdtoa is inlined into cvt which is inlined into vfprintf. This reduced
testcase reproduces on x86_64-linux too.
