public inbox for gcc-prs@sourceware.org
help / color / mirror / Atom feed
* Re: target/6526: [SH4] sdivsi3_i4 can clobber xd0/xd2
@ 2003-05-10 7:56 Dara Hazeghi
0 siblings, 0 replies; 3+ messages in thread
From: Dara Hazeghi @ 2003-05-10 7:56 UTC (permalink / raw)
To: nobody; +Cc: gcc-prs
The following reply was made to PR target/6526; it has been noted by GNATS.
From: Dara Hazeghi <dhazeghi@yahoo.com>
To: gcc-gnats@gcc.gnu.org, marcus@mc.pp.se
Cc:
Subject: Re: target/6526: [SH4] sdivsi3_i4 can clobber xd0/xd2
Date: Sat, 10 May 2003 00:53:43 -0700
http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-
trail&database=gcc&pr=6526
Hello,
could the submitter please verify if this problem still occurs in a
more current version of gcc (ie 3.2.3) ? If so, could the submitter
please send a self-contained testcase demonstrating this problem?
Thanks,
Dara
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: target/6526: [SH4] sdivsi3_i4 can clobber xd0/xd2
@ 2003-05-12 11:37 giovannibajo
0 siblings, 0 replies; 3+ messages in thread
From: giovannibajo @ 2003-05-12 11:37 UTC (permalink / raw)
To: gcc-bugs, gcc-prs, marcus, nobody
Synopsis: [SH4] sdivsi3_i4 can clobber xd0/xd2
State-Changed-From-To: open->analyzed
State-Changed-By: bajo
State-Changed-When: Mon May 12 11:28:47 2003
State-Changed-Why:
Confirmed to still exist in 3.3 branch and mainline.
http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=6526
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: target/6526: [SH4] sdivsi3_i4 can clobber xd0/xd2
@ 2003-05-10 15:56 Marcus Comstedt
0 siblings, 0 replies; 3+ messages in thread
From: Marcus Comstedt @ 2003-05-10 15:56 UTC (permalink / raw)
To: nobody; +Cc: gcc-prs
The following reply was made to PR target/6526; it has been noted by GNATS.
From: Marcus Comstedt <marcus@mc.pp.se>
To: Dara Hazeghi <dhazeghi@yahoo.com>
Cc: gcc-gnats@gcc.gnu.org
Subject: Re: target/6526: [SH4] sdivsi3_i4 can clobber xd0/xd2
Date: 10 May 2003 17:53:25 +0200
Dara Hazeghi <dhazeghi@yahoo.com> writes:
> Hello,
>
> could the submitter please verify if this problem still occurs in a
> more current version of gcc (ie 3.2.3) ? If so, could the submitter
> please send a self-contained testcase demonstrating this problem?
> Thanks,
I don't have a 3.2.3 compiled, but I can verify that it still occurs
with the 20030421 snapshot of 3.3.
Here is a testcase:
--8<-- testcase.c --8<--
void write_xf0(float f)
{
__asm__ __volatile__("frchg; fmov.s @%0,fr0; frchg" : : "r" (&f));
}
float read_xf0()
{
float f;
__asm__ __volatile__("frchg; fmov.s fr0,@%0; frchg" : : "r" (&f));
return f;
}
int do_stuff(int a, int b)
{
int z;
write_xf0(7.0);
z = a % b;
return z+(int)read_xf0();
}
int testfunc()
{
/* Set FPSCR.FR to 1, selecting register bank 1 */
__set_fpscr(0x200000);
return do_stuff(42, 17);
}
--8<--
Compile with `sh-elf-gcc -m4-single-only -c testcase.c', use
`-m4-single-only' when linking as well.
With the current libgcc implementation, testfunc() will return 10, not
15 as expected.
Also, you can change the declaration of do_stuff() to make both args
unsigned int, to see that udivsi3_i4 has the same problem.
Btw, here is a patch to gcc/config/sh/lib1funcs.asm which fixes the
problem for both functions concerned:
---8<---
--- lib1funcs.asm.orig Sat May 10 17:48:43 2003
+++ lib1funcs.asm Sat May 10 17:50:28 2003
@@ -893,18 +893,21 @@
#endif
.global GLOBAL(sdivsi3_i4)
GLOBAL(sdivsi3_i4):
- sts.l fpscr,@-r15
- mov #8,r2
- swap.w r2,r2
- lds r2,fpscr
+ mov.l r3,@-r15
+ sts fpscr,r2
+ mov #8,r3
+ swap.w r3,r3
+ or r2,r3
+ lds r3,fpscr
lds r4,fpul
float fpul,dr0
lds r5,fpul
float fpul,dr2
fdiv dr2,dr0
ftrc dr0,fpul
+ lds r2,fpscr
rts
- lds.l @r15+,fpscr
+ mov.l @r15+,r3
#endif /* ! __SH5__ || __SH5__ == 32 */
#endif /* ! __SH4__ */
@@ -1243,11 +1246,20 @@
mov #1,r1
cmp/hi r1,r5
bf trivial
- sts.l fpscr,@-r15
- mova L1,r0
- lds.l @r0+,fpscr
+ sts fpscr,r0
rotr r1
+ mov.l r0,@-r15
xor r1,r4
+ xor r1,r5
+#ifndef FMOVD_WORKS
+ mov #0x8,r1
+#else
+ mov #0x18,r1
+#endif
+ swap.w r1,r1
+ or r0,r1
+ mova L1,r0
+ lds r1,fpscr
lds r4,fpul
#ifdef FMOVD_WORKS
fmov.d @r0+,dr4
@@ -1261,7 +1273,6 @@
#endif
#endif
float fpul,dr0
- xor r1,r5
lds r5,fpul
float fpul,dr2
fadd dr4,dr0
@@ -1271,20 +1282,16 @@
rts
lds.l @r15+,fpscr
-#ifdef FMOVD_WORKS
- .align 3 ! make double below 8 byte aligned.
-#endif
trivial:
rts
lds r4,fpul
- .align 2
-L1:
-#ifndef FMOVD_WORKS
- .long 0x80000
+#ifdef FMOVD_WORKS
+ .align 3 ! make double below 8 byte aligned.
#else
- .long 0x180000
+ .align 2
#endif
+L1:
.double 2147483648
#endif /* ! __SH4__ */
---8<---
Hope this helps.
// Marcus
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2003-05-12 11:35 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2003-05-10 7:56 target/6526: [SH4] sdivsi3_i4 can clobber xd0/xd2 Dara Hazeghi
2003-05-10 15:56 Marcus Comstedt
2003-05-12 11:37 giovannibajo
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).