| Message ID | 20180111181105.GA20208@ibm-tiger.the-meissners.org |
|---|---|
| State | New |
| Headers | show |
| Series | , Set PowerPC .gnu_attribute for long double use if no call | expand |
On Thu, Jan 11, 2018 at 01:11:05PM -0500, Michael Meissner wrote: > In working on the transition of PowerPC long double from using the IBM extended > double format to IEEE 128-bit floating point, I noticed that the long double > .gnu_attribute (#4) was not set if the compiler can handle long double directly > without doing the call to an emulator, such as using IEEE 128-bit floating > point on an ISA 3.0 (power9) 64-bit system. This patch sets the attribute if > there is a move of the appropriate type. I only check TF/TCmode for the normal > case, and DF/DCmode for -mlong-double-64, since IFmode is used for __ibm128 > when long double is IEEE and KFmode is used for __float128 when long double is > IEEE. > > I have checked this on a little endian power8 system with bootstrap and make > check. There were no regressions, and I verified that the three new tests are > run and pass. Can I check this into the trunk? > [gcc] > 2018-01-11 Michael Meissner <meissner@linux.vnet.ibm.com> > > (rs6000_emit_move): If we load or store a long double type, set > the flags for noting the default long double type, even if we > don't pass or return a long double type. > > [gcc/testsuite] > 2018-01-11 Michael Meissner <meissner@linux.vnet.ibm.com> > > * gcc.target/powerpc/gnuattr1.c: New test to make sure we set the > appropriate .gnu_attribute for the long double type, if we use the > long double type, but do not generate any calls. > * gcc.target/powerpc/gnuattr2.c: Likewise. > * gcc.target/powerpc/gnuattr3.c: Likewise. > + if (rs6000_gnu_attr > + && ((HAVE_LD_PPC_GNU_ATTR_LONG_DOUBLE || TARGET_64BIT)) One pair of parens is enough ;-) > + && ((TARGET_LONG_DOUBLE_128 > + && (mode == TFmode || mode == TCmode)) > + || (!TARGET_LONG_DOUBLE_128 > + && (mode == DFmode || mode == DCmode)))) It's easier to read if you join these lines pairwise: > + && ((TARGET_LONG_DOUBLE_128 && (mode == TFmode || mode == TCmode)) > + || (!TARGET_LONG_DOUBLE_128 && (mode == DFmode || mode == DCmode)))) Or maybe something with ?:, or break the statement into multiple. Okay for trunk if you make it a bit more readable :-) Thanks, Segher
On Fri, Jan 12, 2018 at 11:21:04AM -0600, Segher Boessenkool wrote: > On Thu, Jan 11, 2018 at 01:11:05PM -0500, Michael Meissner wrote: > > In working on the transition of PowerPC long double from using the IBM extended > > double format to IEEE 128-bit floating point, I noticed that the long double > > .gnu_attribute (#4) was not set if the compiler can handle long double directly > > without doing the call to an emulator, such as using IEEE 128-bit floating > > point on an ISA 3.0 (power9) 64-bit system. This patch sets the attribute if > > there is a move of the appropriate type. I only check TF/TCmode for the normal > > case, and DF/DCmode for -mlong-double-64, since IFmode is used for __ibm128 > > when long double is IEEE and KFmode is used for __float128 when long double is > > IEEE. > > > > I have checked this on a little endian power8 system with bootstrap and make > > check. There were no regressions, and I verified that the three new tests are > > run and pass. Can I check this into the trunk? > > > [gcc] > > 2018-01-11 Michael Meissner <meissner@linux.vnet.ibm.com> > > > > (rs6000_emit_move): If we load or store a long double type, set > > the flags for noting the default long double type, even if we > > don't pass or return a long double type. > > > > [gcc/testsuite] > > 2018-01-11 Michael Meissner <meissner@linux.vnet.ibm.com> > > > > * gcc.target/powerpc/gnuattr1.c: New test to make sure we set the > > appropriate .gnu_attribute for the long double type, if we use the > > long double type, but do not generate any calls. > > * gcc.target/powerpc/gnuattr2.c: Likewise. > > * gcc.target/powerpc/gnuattr3.c: Likewise. > > > > + if (rs6000_gnu_attr > > + && ((HAVE_LD_PPC_GNU_ATTR_LONG_DOUBLE || TARGET_64BIT)) > > One pair of parens is enough ;-) > > > + && ((TARGET_LONG_DOUBLE_128 > > + && (mode == TFmode || mode == TCmode)) > > + || (!TARGET_LONG_DOUBLE_128 > > + && (mode == DFmode || mode == DCmode)))) > > It's easier to read if you join these lines pairwise: > > > + && ((TARGET_LONG_DOUBLE_128 && (mode == TFmode || mode == TCmode)) > > + || (!TARGET_LONG_DOUBLE_128 && (mode == DFmode || mode == DCmode)))) > > Or maybe something with ?:, or break the statement into multiple. > > Okay for trunk if you make it a bit more readable :-) Thanks, This is what I just checked in: Index: gcc/config/rs6000/rs6000.c =================================================================== --- gcc/config/rs6000/rs6000.c (revision 256810) +++ gcc/config/rs6000/rs6000.c (working copy) @@ -10493,6 +10493,23 @@ rs6000_emit_move (rtx dest, rtx source, gcc_unreachable (); } +#ifdef HAVE_AS_GNU_ATTRIBUTE + /* If we use a long double type, set the flags in .gnu_attribute that say + what the long double type is. This is to allow the linker's warning + message for the wrong long double to be useful, even if the function does + not do a call (for example, doing a 128-bit add on power9 if the long + double type is IEEE 128-bit. Do not set this if __ibm128 or __floa128 are + used if they aren't the default long dobule type. */ + if (rs6000_gnu_attr && (HAVE_LD_PPC_GNU_ATTR_LONG_DOUBLE || TARGET_64BIT)) + { + if (TARGET_LONG_DOUBLE_128 && (mode == TFmode || mode == TCmode)) + rs6000_passes_float = rs6000_passes_long_double = true; + + else if (!TARGET_LONG_DOUBLE_128 && (mode == DFmode || mode == DCmode)) + rs6000_passes_float = rs6000_passes_long_double = true; + } +#endif + /* See if we need to special case SImode/SFmode SUBREG moves. */ if ((mode == SImode || mode == SFmode) && SUBREG_P (source) && rs6000_emit_move_si_sf_subreg (dest, source, mode))
Index: gcc/config/rs6000/rs6000.c =================================================================== --- gcc/config/rs6000/rs6000.c (revision 256534) +++ gcc/config/rs6000/rs6000.c (working copy) @@ -10505,6 +10505,22 @@ rs6000_emit_move (rtx dest, rtx source, gcc_unreachable (); } +#ifdef HAVE_AS_GNU_ATTRIBUTE + /* If we use a long double type, set the flags in .gnu_attribute that say + what the long double type is. This is to allow the linker's warning + message for the wrong long double to be useful, even if the function does + not do a call (for example, doing a 128-bit add on power9 if the long + double type is IEEE 128-bit. Do not set this if __ibm128 or __floa128 are + used if they aren't the default long dobule type. */ + if (rs6000_gnu_attr + && ((HAVE_LD_PPC_GNU_ATTR_LONG_DOUBLE || TARGET_64BIT)) + && ((TARGET_LONG_DOUBLE_128 + && (mode == TFmode || mode == TCmode)) + || (!TARGET_LONG_DOUBLE_128 + && (mode == DFmode || mode == DCmode)))) + rs6000_passes_float = rs6000_passes_long_double = true; +#endif + /* See if we need to special case SImode/SFmode SUBREG moves. */ if ((mode == SImode || mode == SFmode) && SUBREG_P (source) && rs6000_emit_move_si_sf_subreg (dest, source, mode)) Index: gcc/testsuite/gcc.target/powerpc/gnuattr1.c =================================================================== --- gcc/testsuite/gcc.target/powerpc/gnuattr1.c (nonexistent) +++ gcc/testsuite/gcc.target/powerpc/gnuattr1.c (working copy) @@ -0,0 +1,15 @@ +/* { dg-do compile { target { powerpc*-linux-* } } } */ +/* { dg-require-effective-target powerpc_vsx_ok } */ +/* { dg-options "-O2 -mvsx -mlong-double-64" } */ +/* { dg-final { scan-assembler "gnu_attribute 4, 9" } } */ + +/* Check that if we can do the long double operation without doing an emulator + call, such as with 64-bit long double support, that we still set the + appropriate .gnu_attribute. */ + +long double a; + +void add1 (void) +{ + a++; +} Index: gcc/testsuite/gcc.target/powerpc/gnuattr2.c =================================================================== --- gcc/testsuite/gcc.target/powerpc/gnuattr2.c (nonexistent) +++ gcc/testsuite/gcc.target/powerpc/gnuattr2.c (working copy) @@ -0,0 +1,17 @@ +/* { dg-do compile { target { powerpc*-linux-* && lp64 } } } */ +/* { dg-require-effective-target powerpc_p9vector_ok } */ +/* { dg-options "-O2 -mpower9-vector -mabi=ieeelongdouble -Wno-psabi" } */ +/* { dg-final { scan-assembler "gnu_attribute 4, 13" } } */ + +/* Check that if we can do the long double operation without doing an emulator + call, such as with IEEE 128-bit hardware support on power9, that we still + set the appropriate .gnu_attribute. The && lp64 is needed, because we can't + enable the IEEE 128-bit hardware instructions on ISA 3.0 (power9) in 32-bit, + because we don't have a TImode available. */ + +long double a; + +void add1 (void) +{ + a++; +} Index: gcc/testsuite/gcc.target/powerpc/gnuattr3.c =================================================================== --- gcc/testsuite/gcc.target/powerpc/gnuattr3.c (nonexistent) +++ gcc/testsuite/gcc.target/powerpc/gnuattr3.c (working copy) @@ -0,0 +1,15 @@ +/* { dg-do compile { target { powerpc*-linux-* } } } */ +/* { dg-require-effective-target powerpc_vsx_ok } */ +/* { dg-options "-O2 -mvsx -mabi=ibmlongdouble -Wno-psabi" } */ +/* { dg-final { scan-assembler "gnu_attribute 4, 5" } } */ + +/* Check that if we can do the long double operation without doing an emulator + call, such as with copysign, that we still set the appropriate + .gnu_attribute. */ + +long double a, b, c; + +void cs (void) +{ + a = __builtin_copysignl (b, c); +}