Re: SSE2 instructions emitted in libcompiler_rt
On Fri, Sep 08, 2017 at 10:15:25AM -0700, Mike Larkin wrote:
> On Thu, Sep 07, 2017 at 06:52:34PM +0200, Christian Weisgerber wrote:
> > Christian Weisgerber:
> >
> > > > Maybe this would already help? Would at least not throw stones into the
> > > > way of the next person doing an upgrade of compiler-rt...
> > > -snip-
> > >
> > > Yes, that's better... but errors out:
> > > make: don't know how to make floatdixf.c.c (prerequisite of:
> > > floatdixf.c.o)
> >
> > Oh, it's a typo. The fixed version looks fine to me.
> > However, I don't know how to test that these functions actually work.
> >
> > Index: Makefile
> > ===
> > RCS file: /cvs/src/lib/libcompiler_rt/Makefile,v
> > retrieving revision 1.9
> > diff -u -p -r1.9 Makefile
> > --- Makefile4 Aug 2017 12:00:59 - 1.9
> > +++ Makefile7 Sep 2017 16:47:31 -
> > @@ -89,17 +89,11 @@ GEN_SRCS= absvdi2 \
> > fixunsxfti \
> > fixxfdi \
> > fixxfti \
> > - floatdidf \
> > - floatdisf \
> > - floatdixf \
> > floatsidf \
> > floatsisf \
> > floattidf \
> > floattisf \
> > floattixf \
> > - floatundidf \
> > - floatundisf \
> > - floatundixf \
> > floatunsidf \
> > floatunsisf \
> > floatuntidf \
> > @@ -164,6 +158,22 @@ GEN_SRCS= absvdi2 \
> > umoddi3 \
> > umodsi3 \
> > umodti3
> > +
> > +.if ${RTARCH} == "i386"
> > +SRCS+= floatdidf.c \
> > + floatdisf.c \
> > + floatdixf.c \
> > + floatundidf.c \
> > + floatundisf.c \
> > + floatundixf.c
> > +.else
> > +GEN_SRCS+= floatdidf \
> > + floatdisf \
> > + floatdixf \
> > + floatundidf \
> > + floatundisf \
> > + floatundixf
> > +.endif
> >
> > .for file in ${GEN_SRCS}
> > . if exists(${.CURDIR}/${RTARCH}/${file}.S)
> > --
> > Christian "naddy" Weisgerber na...@mips.inka.de
> >
>
> ok mlarkin if you want to head this way. Thanks for the later verification
> that these don't appear to be used on i386 base anyway.
>
ok patrick as well
Re: SSE2 instructions emitted in libcompiler_rt
Christian Weisgerber:
> > Maybe this would already help? Would at least not throw stones into the
> > way of the next person doing an upgrade of compiler-rt...
> -snip-
>
> Yes, that's better... but errors out:
> make: don't know how to make floatdixf.c.c (prerequisite of: floatdixf.c.o)
Oh, it's a typo. The fixed version looks fine to me.
However, I don't know how to test that these functions actually work.
Index: Makefile
===
RCS file: /cvs/src/lib/libcompiler_rt/Makefile,v
retrieving revision 1.9
diff -u -p -r1.9 Makefile
--- Makefile4 Aug 2017 12:00:59 - 1.9
+++ Makefile7 Sep 2017 16:47:31 -
@@ -89,17 +89,11 @@ GEN_SRCS= absvdi2 \
fixunsxfti \
fixxfdi \
fixxfti \
- floatdidf \
- floatdisf \
- floatdixf \
floatsidf \
floatsisf \
floattidf \
floattisf \
floattixf \
- floatundidf \
- floatundisf \
- floatundixf \
floatunsidf \
floatunsisf \
floatuntidf \
@@ -164,6 +158,22 @@ GEN_SRCS= absvdi2 \
umoddi3 \
umodsi3 \
umodti3
+
+.if ${RTARCH} == "i386"
+SRCS+= floatdidf.c \
+ floatdisf.c \
+ floatdixf.c \
+ floatundidf.c \
+ floatundisf.c \
+ floatundixf.c
+.else
+GEN_SRCS+= floatdidf \
+ floatdisf \
+ floatdixf \
+ floatundidf \
+ floatundisf \
+ floatundixf
+.endif
.for file in ${GEN_SRCS}
. if exists(${.CURDIR}/${RTARCH}/${file}.S)
--
Christian "naddy" Weisgerber na...@mips.inka.de
Re: SSE2 instructions emitted in libcompiler_rt
Patrick Wildt: > Maybe this would already help? Would at least not throw stones into the > way of the next person doing an upgrade of compiler-rt... -snip- Yes, that's better... but errors out: make: don't know how to make floatdixf.c.c (prerequisite of: floatdixf.c.o) -- Christian "naddy" Weisgerber na...@mips.inka.de
Re: SSE2 instructions emitted in libcompiler_rt
On Wed, Sep 06, 2017 at 11:54:38PM +0200, Patrick Wildt wrote:
> On Wed, Sep 06, 2017 at 11:43:15PM +0200, Christian Weisgerber wrote:
> > Somebody noticed this on FreeBSD:
> > https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=221733
> >
> > On i386, libcompiler_rt includes assembly implementations for
> > floating point conversion functions that unconditionally use SSE2
> > instructions, which are not supported by older CPUs. Specifically,
> > these files:
> >
> > floatdidf.S
> > floatdisf.S
> > floatdixf.S
> > floatundidf.S
> > floatundisf.S
> > floatundixf.S
> >
> > We need to use the generic C implementation instead. The way the
> > Makefile is currently set up, I guess we would just delete the
> > affected files under lib/libcompiler_rt/i386/?
> >
> > --
> > Christian "naddy" Weisgerber na...@mips.inka.de
> >
>
> Maybe this would already help? Would at least not throw stones into the
> way of the next person doing an upgrade of compiler-rt...
>
> Patrick
>
> diff --git a/lib/libcompiler_rt/Makefile b/lib/libcompiler_rt/Makefile
> index f82c8156c2f..070b6e7cbde 100644
> --- a/lib/libcompiler_rt/Makefile
> +++ b/lib/libcompiler_rt/Makefile
> @@ -89,17 +89,11 @@ GEN_SRCS= absvdi2 \
> fixunsxfti \
> fixxfdi \
> fixxfti \
> - floatdidf \
> - floatdisf \
> - floatdixf \
> floatsidf \
> floatsisf \
> floattidf \
> floattisf \
> floattixf \
> - floatundidf \
> - floatundisf \
> - floatundixf \
> floatunsidf \
> floatunsisf \
> floatuntidf \
> @@ -165,6 +159,22 @@ GEN_SRCS=absvdi2 \
> umodsi3 \
> umodti3
>
> +.if ${RTARCH} == "i386"
> +SRCS+= floatdidf.c \
> + floatdisf.c \
> + floatdixf.c.c \
> + floatundidf.c \
> + floatundisf.c \
> + floatundixf.c
> +.else
> +GEN_SRCS+= floatdidf \
> + floatdisf \
> + floatdixf \
> + floatundidf \
> + floatundisf \
> + floatundixf
> +.endif
> +
> .for file in ${GEN_SRCS}
> .if exists(${.CURDIR}/${RTARCH}/${file}.S)
> SRCS+= ${file}.S
>
this looks ok to me. I can run at least a build test later, but I don't
have any hardware that lacks these instructions.
-ml
Re: SSE2 instructions emitted in libcompiler_rt
On Wed, Sep 06, 2017 at 11:43:15PM +0200, Christian Weisgerber wrote: > Somebody noticed this on FreeBSD: > https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=221733 > > On i386, libcompiler_rt includes assembly implementations for > floating point conversion functions that unconditionally use SSE2 > instructions, which are not supported by older CPUs. Specifically, > these files: > > floatdidf.S > floatdisf.S > floatdixf.S > floatundidf.S > floatundisf.S > floatundixf.S > > We need to use the generic C implementation instead. The way the > Makefile is currently set up, I guess we would just delete the > affected files under lib/libcompiler_rt/i386/? > > -- > Christian "naddy" Weisgerber na...@mips.inka.de > Removing sse2 instructions on i386 seems to be the right thing to do. Whether or not it's a simple makefile change or removing files from libcompiler_rt/i386, I'm not sure. Did you try to remove these files and did it work? -ml
Re: SSE2 instructions emitted in libcompiler_rt
On Wed, Sep 06, 2017 at 11:43:15PM +0200, Christian Weisgerber wrote:
> Somebody noticed this on FreeBSD:
> https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=221733
>
> On i386, libcompiler_rt includes assembly implementations for
> floating point conversion functions that unconditionally use SSE2
> instructions, which are not supported by older CPUs. Specifically,
> these files:
>
> floatdidf.S
> floatdisf.S
> floatdixf.S
> floatundidf.S
> floatundisf.S
> floatundixf.S
>
> We need to use the generic C implementation instead. The way the
> Makefile is currently set up, I guess we would just delete the
> affected files under lib/libcompiler_rt/i386/?
>
> --
> Christian "naddy" Weisgerber na...@mips.inka.de
>
Maybe this would already help? Would at least not throw stones into the
way of the next person doing an upgrade of compiler-rt...
Patrick
diff --git a/lib/libcompiler_rt/Makefile b/lib/libcompiler_rt/Makefile
index f82c8156c2f..070b6e7cbde 100644
--- a/lib/libcompiler_rt/Makefile
+++ b/lib/libcompiler_rt/Makefile
@@ -89,17 +89,11 @@ GEN_SRCS= absvdi2 \
fixunsxfti \
fixxfdi \
fixxfti \
- floatdidf \
- floatdisf \
- floatdixf \
floatsidf \
floatsisf \
floattidf \
floattisf \
floattixf \
- floatundidf \
- floatundisf \
- floatundixf \
floatunsidf \
floatunsisf \
floatuntidf \
@@ -165,6 +159,22 @@ GEN_SRCS= absvdi2 \
umodsi3 \
umodti3
+.if ${RTARCH} == "i386"
+SRCS+= floatdidf.c \
+ floatdisf.c \
+ floatdixf.c.c \
+ floatundidf.c \
+ floatundisf.c \
+ floatundixf.c
+.else
+GEN_SRCS+= floatdidf \
+ floatdisf \
+ floatdixf \
+ floatundidf \
+ floatundisf \
+ floatundixf
+.endif
+
.for file in ${GEN_SRCS}
. if exists(${.CURDIR}/${RTARCH}/${file}.S)
SRCS+= ${file}.S
SSE2 instructions emitted in libcompiler_rt
Somebody noticed this on FreeBSD: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=221733 On i386, libcompiler_rt includes assembly implementations for floating point conversion functions that unconditionally use SSE2 instructions, which are not supported by older CPUs. Specifically, these files: floatdidf.S floatdisf.S floatdixf.S floatundidf.S floatundisf.S floatundixf.S We need to use the generic C implementation instead. The way the Makefile is currently set up, I guess we would just delete the affected files under lib/libcompiler_rt/i386/? -- Christian "naddy" Weisgerber na...@mips.inka.de
