* Re: [PATCH] Fix ARM NAN fraction bits [not found] <000b01cf3367$439c5280$cad4f780$@arm.com> @ 2014-05-16 16:58 ` Maciej W. Rozycki 2014-05-16 17:03 ` Joseph S. Myers 0 siblings, 1 reply; 8+ messages in thread From: Maciej W. Rozycki @ 2014-05-16 16:58 UTC (permalink / raw) To: Joey Ye, Joseph S. Myers; +Cc: libc-alpha, gcc-patches On Thu, 27 Feb 2014, Joey Ye wrote: > Current ARM soft-float implementation is violating the RTABI > (http://infocenter.arm.com/help/topic/com.arm.doc.ihi0043d/IHI0043D_rtabi.pd > f) Section 4.1.1.1: > > When not otherwise specified by IEEE 754, the result on an invalid operation > should be the quiet NaN bit pattern with only the most significant bit of > the significand set, and all other significand bits zero. > > This patch fixes it by setting _FP_NANFRAC_* to zero. > > Ran make check test with –mfloat-abi=soft. No regression. > > OK to checkin? > > 2014-02-27 Joey Ye <joey.ye@arm.com> > * sysdeps/arm/soft-fp/sfp-machine.h >   (_FP_NANFRAC_S, _FP_NANFRAC_D, _FP_NANFRAC_Q): >  Set to zero. > > > diff --git a/sysdeps/arm/soft-fp/sfp-machine.h > b/sysdeps/arm/soft-fp/sfp-machine.h > index 52a08b5..32697fe 100644 > --- a/sysdeps/arm/soft-fp/sfp-machine.h > +++ b/sysdeps/arm/soft-fp/sfp-machine.h > @@ -21,9 +21,9 @@ > #define _FP_DIV_MEAT_D(R,X,Y)         _FP_DIV_MEAT_2_udiv(D,R,X,Y) > #define _FP_DIV_MEAT_Q(R,X,Y)         _FP_DIV_MEAT_4_udiv(Q,R,X,Y) > > -#define _FP_NANFRAC_S                         ((_FP_QNANBIT_S << 1) - 1) > -#define _FP_NANFRAC_D                        ((_FP_QNANBIT_D << 1) - 1), > -1 > -#define _FP_NANFRAC_Q                        ((_FP_QNANBIT_Q << 1) - 1), > -1, -1, -1 > +#define _FP_NANFRAC_S                        0 > +#define _FP_NANFRAC_D                       0, 0 > +#define _FP_NANFRAC_Q                       0, 0, 0, 0 > #define _FP_NANSIGN_S                          0 > #define _FP_NANSIGN_D                         0 > #define _FP_NANSIGN_Q                         0 This did regrettably, when propagated to libgcc, regress gcc.dg/torture/builtin-math-7.c on soft-fp arm-eabi targets, currently ARMv6-M (`-march=armv6-m -mthumb') only. This is because these NANFRAC macros have now no bits set and as a result when used to construct a NaN in the semi-raw mode, they build an infinity instead. Consequently operations such as (Inf - Inf) now produce Inf rather than NaN. The change worked for the original test case, because division is made in the canonical mode, where the quiet bit is set separately, from the fp class. Here's a fix making code match the commit description quoted above, that is set the most significant bit of the significand. This is also what targets similar in this respect do. OK to apply? OK for libgcc (against libgcc/config/arm/sfp-machine.h), in particular for GCC 4.8 and 4.9? 2014-05-16 Maciej W. Rozycki <macro@codesourcery.com> PR libgcc/60166 * sysdeps/arm/soft-fp/sfp-machine.h (_FP_NANFRAC_S, _FP_NANFRAC_D) (_FP_NANSIGN_Q): Set the quiet bit. Maciej glibc-soft-fp-arm-nanfrac.diff Index: glibc-fsf-trunk-quilt/sysdeps/arm/soft-fp/sfp-machine.h =================================================================== --- glibc-fsf-trunk-quilt.orig/sysdeps/arm/soft-fp/sfp-machine.h 2014-05-16 03:25:52.000000000 +0100 +++ glibc-fsf-trunk-quilt/sysdeps/arm/soft-fp/sfp-machine.h 2014-05-16 03:31:34.451805339 +0100 @@ -21,9 +21,9 @@ #define _FP_DIV_MEAT_D(R,X,Y) _FP_DIV_MEAT_2_udiv(D,R,X,Y) #define _FP_DIV_MEAT_Q(R,X,Y) _FP_DIV_MEAT_4_udiv(Q,R,X,Y) -#define _FP_NANFRAC_S 0 -#define _FP_NANFRAC_D 0, 0 -#define _FP_NANFRAC_Q 0, 0, 0, 0 +#define _FP_NANFRAC_S _FP_QNANBIT_S +#define _FP_NANFRAC_D _FP_QNANBIT_D, 0 +#define _FP_NANFRAC_Q _FP_QNANBIT_Q, 0, 0, 0 #define _FP_NANSIGN_S 0 #define _FP_NANSIGN_D 0 #define _FP_NANSIGN_Q 0 ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] Fix ARM NAN fraction bits 2014-05-16 16:58 ` [PATCH] Fix ARM NAN fraction bits Maciej W. Rozycki @ 2014-05-16 17:03 ` Joseph S. Myers 2014-05-16 22:23 ` Maciej W. Rozycki 0 siblings, 1 reply; 8+ messages in thread From: Joseph S. Myers @ 2014-05-16 17:03 UTC (permalink / raw) To: Maciej W. Rozycki; +Cc: Joey Ye, libc-alpha, gcc-patches On Fri, 16 May 2014, Maciej W. Rozycki wrote: > 2014-05-16 Maciej W. Rozycki <macro@codesourcery.com> > > PR libgcc/60166 > * sysdeps/arm/soft-fp/sfp-machine.h (_FP_NANFRAC_S, _FP_NANFRAC_D) > (_FP_NANSIGN_Q): Set the quiet bit. OK for glibc. -- Joseph S. Myers joseph@codesourcery.com ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] Fix ARM NAN fraction bits 2014-05-16 17:03 ` Joseph S. Myers @ 2014-05-16 22:23 ` Maciej W. Rozycki 2014-05-17 8:35 ` Richard Biener 0 siblings, 1 reply; 8+ messages in thread From: Maciej W. Rozycki @ 2014-05-16 22:23 UTC (permalink / raw) To: Joseph S. Myers, Richard Biener; +Cc: Joey Ye, libc-alpha, gcc-patches On Fri, 16 May 2014, Joseph S. Myers wrote: > > 2014-05-16 Maciej W. Rozycki <macro@codesourcery.com> > > > > PR libgcc/60166 > > * sysdeps/arm/soft-fp/sfp-machine.h (_FP_NANFRAC_S, _FP_NANFRAC_D) > > (_FP_NANSIGN_Q): Set the quiet bit. > > OK for glibc. Joseph, thanks for your review, this is now in. Richard, you wrote yesterday that pushing changes to 4.8 would require explicit approval from release managers, however it is not clear to me who they are for that branch. This fix corrects a regression introduced after 4.8.2. Can you approve it? If not, then who can? Maciej ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] Fix ARM NAN fraction bits 2014-05-16 22:23 ` Maciej W. Rozycki @ 2014-05-17 8:35 ` Richard Biener 2014-05-20 0:29 ` Maciej W. Rozycki 0 siblings, 1 reply; 8+ messages in thread From: Richard Biener @ 2014-05-17 8:35 UTC (permalink / raw) To: Maciej W. Rozycki, Joseph S. Myers; +Cc: Joey Ye, libc-alpha, gcc-patches On May 17, 2014 12:22:23 AM CEST, "Maciej W. Rozycki" <macro@codesourcery.com> wrote: >On Fri, 16 May 2014, Joseph S. Myers wrote: > >> > 2014-05-16 Maciej W. Rozycki <macro@codesourcery.com> >> > >> > PR libgcc/60166 >> > * sysdeps/arm/soft-fp/sfp-machine.h (_FP_NANFRAC_S, _FP_NANFRAC_D) >> > (_FP_NANSIGN_Q): Set the quiet bit. >> >> OK for glibc. > > Joseph, thanks for your review, this is now in. > >Richard, you wrote yesterday that pushing changes to 4.8 would require >explicit approval from release managers, however it is not clear to me >who >they are for that branch. This fix corrects a regression introduced >after >4.8.2. Can you approve it? If not, then who can? If it's not broken in 4.8.2 but broken on the branch head then it's OK for the branch. Thanks, Richard. > Maciej ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] Fix ARM NAN fraction bits 2014-05-17 8:35 ` Richard Biener @ 2014-05-20 0:29 ` Maciej W. Rozycki 2014-05-20 7:59 ` Richard Biener 0 siblings, 1 reply; 8+ messages in thread From: Maciej W. Rozycki @ 2014-05-20 0:29 UTC (permalink / raw) To: Ian Lance Taylor; +Cc: Richard Biener, gcc-patches Ian, On Sat, 17 May 2014, Richard Biener wrote: > On May 17, 2014 12:22:23 AM CEST, "Maciej W. Rozycki" <macro@codesourcery.com> wrote: > >On Fri, 16 May 2014, Joseph S. Myers wrote: > > > >> > 2014-05-16 Maciej W. Rozycki <macro@codesourcery.com> > >> > > >> > PR libgcc/60166 > >> > * sysdeps/arm/soft-fp/sfp-machine.h (_FP_NANFRAC_S, _FP_NANFRAC_D) > >> > (_FP_NANSIGN_Q): Set the quiet bit. > >> > >> OK for glibc. > > > > Joseph, thanks for your review, this is now in. > > > >Richard, you wrote yesterday that pushing changes to 4.8 would require > >explicit approval from release managers, however it is not clear to me > >who > >they are for that branch. This fix corrects a regression introduced > >after > >4.8.2. Can you approve it? If not, then who can? > > If it's not broken in 4.8.2 but broken on the branch head then it's OK > for the branch. I thought I'd double-check with you that it is fine to push this change to trunk first. OK to apply? 2014-05-20 Maciej W. Rozycki <macro@codesourcery.com> PR libgcc/60166 libgcc/ * config/arm/sfp-machine.h (_FP_NANFRAC_S, _FP_NANFRAC_D) (_FP_NANSIGN_Q): Set the quiet bit. Maciej gcc-soft-fp-arm-nanfrac.diff Index: gcc-fsf-trunk-quilt/libgcc/config/arm/sfp-machine.h =================================================================== --- gcc-fsf-trunk-quilt.orig/libgcc/config/arm/sfp-machine.h 2014-05-16 15:59:06.000000000 +0100 +++ gcc-fsf-trunk-quilt/libgcc/config/arm/sfp-machine.h 2014-05-20 01:23:36.618434199 +0100 @@ -21,10 +21,10 @@ typedef int __gcc_CMPtype __attribute__ /* According to RTABI, QNAN is only with the most significant bit of the significand set, and all other significand bits zero. */ -#define _FP_NANFRAC_H 0 -#define _FP_NANFRAC_S 0 -#define _FP_NANFRAC_D 0, 0 -#define _FP_NANFRAC_Q 0, 0, 0, 0 +#define _FP_NANFRAC_H _FP_QNANBIT_H +#define _FP_NANFRAC_S _FP_QNANBIT_S +#define _FP_NANFRAC_D _FP_QNANBIT_D, 0 +#define _FP_NANFRAC_Q _FP_QNANBIT_Q, 0, 0, 0 #define _FP_NANSIGN_H 0 #define _FP_NANSIGN_S 0 #define _FP_NANSIGN_D 0 ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] Fix ARM NAN fraction bits 2014-05-20 0:29 ` Maciej W. Rozycki @ 2014-05-20 7:59 ` Richard Biener 2014-05-20 12:58 ` Richard Earnshaw 0 siblings, 1 reply; 8+ messages in thread From: Richard Biener @ 2014-05-20 7:59 UTC (permalink / raw) To: Maciej W. Rozycki; +Cc: Ian Lance Taylor, gcc-patches On Tue, 20 May 2014, Maciej W. Rozycki wrote: > Ian, > > On Sat, 17 May 2014, Richard Biener wrote: > > > On May 17, 2014 12:22:23 AM CEST, "Maciej W. Rozycki" <macro@codesourcery.com> wrote: > > >On Fri, 16 May 2014, Joseph S. Myers wrote: > > > > > >> > 2014-05-16 Maciej W. Rozycki <macro@codesourcery.com> > > >> > > > >> > PR libgcc/60166 > > >> > * sysdeps/arm/soft-fp/sfp-machine.h (_FP_NANFRAC_S, _FP_NANFRAC_D) > > >> > (_FP_NANSIGN_Q): Set the quiet bit. > > >> > > >> OK for glibc. > > > > > > Joseph, thanks for your review, this is now in. > > > > > >Richard, you wrote yesterday that pushing changes to 4.8 would require > > >explicit approval from release managers, however it is not clear to me > > >who > > >they are for that branch. This fix corrects a regression introduced > > >after > > >4.8.2. Can you approve it? If not, then who can? > > > > If it's not broken in 4.8.2 but broken on the branch head then it's OK > > for the branch. > > I thought I'd double-check with you that it is fine to push this change > to trunk first. OK to apply? Of course it should go to trunk (and 4.9 branch) first, but I'm not the one to approve that. Richard. > 2014-05-20 Maciej W. Rozycki <macro@codesourcery.com> > > PR libgcc/60166 > libgcc/ > * config/arm/sfp-machine.h (_FP_NANFRAC_S, _FP_NANFRAC_D) > (_FP_NANSIGN_Q): Set the quiet bit. > > Maciej > > gcc-soft-fp-arm-nanfrac.diff > Index: gcc-fsf-trunk-quilt/libgcc/config/arm/sfp-machine.h > =================================================================== > --- gcc-fsf-trunk-quilt.orig/libgcc/config/arm/sfp-machine.h 2014-05-16 15:59:06.000000000 +0100 > +++ gcc-fsf-trunk-quilt/libgcc/config/arm/sfp-machine.h 2014-05-20 01:23:36.618434199 +0100 > @@ -21,10 +21,10 @@ typedef int __gcc_CMPtype __attribute__ > > /* According to RTABI, QNAN is only with the most significant bit of the > significand set, and all other significand bits zero. */ > -#define _FP_NANFRAC_H 0 > -#define _FP_NANFRAC_S 0 > -#define _FP_NANFRAC_D 0, 0 > -#define _FP_NANFRAC_Q 0, 0, 0, 0 > +#define _FP_NANFRAC_H _FP_QNANBIT_H > +#define _FP_NANFRAC_S _FP_QNANBIT_S > +#define _FP_NANFRAC_D _FP_QNANBIT_D, 0 > +#define _FP_NANFRAC_Q _FP_QNANBIT_Q, 0, 0, 0 > #define _FP_NANSIGN_H 0 > #define _FP_NANSIGN_S 0 > #define _FP_NANSIGN_D 0 > > ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] Fix ARM NAN fraction bits 2014-05-20 7:59 ` Richard Biener @ 2014-05-20 12:58 ` Richard Earnshaw 2014-05-21 2:17 ` Maciej W. Rozycki 0 siblings, 1 reply; 8+ messages in thread From: Richard Earnshaw @ 2014-05-20 12:58 UTC (permalink / raw) To: Richard Biener; +Cc: Maciej W. Rozycki, Ian Lance Taylor, gcc-patches On 20/05/14 08:57, Richard Biener wrote: > On Tue, 20 May 2014, Maciej W. Rozycki wrote: > >> Ian, >> >> On Sat, 17 May 2014, Richard Biener wrote: >> >>> On May 17, 2014 12:22:23 AM CEST, "Maciej W. Rozycki" <macro@codesourcery.com> wrote: >>>> On Fri, 16 May 2014, Joseph S. Myers wrote: >>>> >>>>>> 2014-05-16 Maciej W. Rozycki <macro@codesourcery.com> >>>>>> >>>>>> PR libgcc/60166 >>>>>> * sysdeps/arm/soft-fp/sfp-machine.h (_FP_NANFRAC_S, _FP_NANFRAC_D) >>>>>> (_FP_NANSIGN_Q): Set the quiet bit. >>>>> >>>>> OK for glibc. >>>> >>>> Joseph, thanks for your review, this is now in. >>>> >>>> Richard, you wrote yesterday that pushing changes to 4.8 would require >>>> explicit approval from release managers, however it is not clear to me >>>> who >>>> they are for that branch. This fix corrects a regression introduced >>>> after >>>> 4.8.2. Can you approve it? If not, then who can? >>> >>> If it's not broken in 4.8.2 but broken on the branch head then it's OK >>> for the branch. >> >> I thought I'd double-check with you that it is fine to push this change >> to trunk first. OK to apply? > > Of course it should go to trunk (and 4.9 branch) first, but I'm not > the one to approve that. > I can... Based on Joseph's review, OK. R. > Richard. > >> 2014-05-20 Maciej W. Rozycki <macro@codesourcery.com> >> >> PR libgcc/60166 >> libgcc/ >> * config/arm/sfp-machine.h (_FP_NANFRAC_S, _FP_NANFRAC_D) >> (_FP_NANSIGN_Q): Set the quiet bit. >> >> Maciej >> >> gcc-soft-fp-arm-nanfrac.diff >> Index: gcc-fsf-trunk-quilt/libgcc/config/arm/sfp-machine.h >> =================================================================== >> --- gcc-fsf-trunk-quilt.orig/libgcc/config/arm/sfp-machine.h 2014-05-16 15:59:06.000000000 +0100 >> +++ gcc-fsf-trunk-quilt/libgcc/config/arm/sfp-machine.h 2014-05-20 01:23:36.618434199 +0100 >> @@ -21,10 +21,10 @@ typedef int __gcc_CMPtype __attribute__ >> >> /* According to RTABI, QNAN is only with the most significant bit of the >> significand set, and all other significand bits zero. */ >> -#define _FP_NANFRAC_H 0 >> -#define _FP_NANFRAC_S 0 >> -#define _FP_NANFRAC_D 0, 0 >> -#define _FP_NANFRAC_Q 0, 0, 0, 0 >> +#define _FP_NANFRAC_H _FP_QNANBIT_H >> +#define _FP_NANFRAC_S _FP_QNANBIT_S >> +#define _FP_NANFRAC_D _FP_QNANBIT_D, 0 >> +#define _FP_NANFRAC_Q _FP_QNANBIT_Q, 0, 0, 0 >> #define _FP_NANSIGN_H 0 >> #define _FP_NANSIGN_S 0 >> #define _FP_NANSIGN_D 0 >> >> > ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] Fix ARM NAN fraction bits 2014-05-20 12:58 ` Richard Earnshaw @ 2014-05-21 2:17 ` Maciej W. Rozycki 0 siblings, 0 replies; 8+ messages in thread From: Maciej W. Rozycki @ 2014-05-21 2:17 UTC (permalink / raw) To: Richard Earnshaw, Richard Biener; +Cc: gcc-patches On Tue, 20 May 2014, Richard Earnshaw wrote: > >>> If it's not broken in 4.8.2 but broken on the branch head then it's OK > >>> for the branch. > >> > >> I thought I'd double-check with you that it is fine to push this change > >> to trunk first. OK to apply? > > > > Of course it should go to trunk (and 4.9 branch) first, but I'm not > > the one to approve that. > > > > I can... Based on Joseph's review, OK. I have now applied it to trunk and backported to 4.9 and 4.8. Thank you both for the review. Maciej ^ permalink raw reply [flat|nested] 8+ messages in thread
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[not found] <000b01cf3367$439c5280$cad4f780$@arm.com>
2014-05-16 16:58 ` [PATCH] Fix ARM NAN fraction bits Maciej W. Rozycki
2014-05-16 17:03 ` Joseph S. Myers
2014-05-16 22:23 ` Maciej W. Rozycki
2014-05-17 8:35 ` Richard Biener
2014-05-20 0:29 ` Maciej W. Rozycki
2014-05-20 7:59 ` Richard Biener
2014-05-20 12:58 ` Richard Earnshaw
2014-05-21 2:17 ` Maciej W. Rozycki
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