In 4.4, the LEADZ and TRAILZ intrinsics were added. LEADZ is one of the HPF intrinsics. However the other HPF bit intrinsics, POPCNT and POPPAR, were not included. POPCNT and POPPAR are present in many other compilers, and have usually been implemented along with LEADZ. This is because historically, POPCNT, POPPAR, and LEADZ were present in the Cray compilers to allow access to hardware instructions. So it is a little strange to see LEADZ without the others. Both POPCNT and POPPAR are also present in the F2008 draft.

(In reply to comment #0) > POPCNT and POPPAR are present in many other compilers And (even) more interestingly they are part of the Fortran 2008 Candidate Release (as you also mentioned): 13.7.128 POPCNT (I) Description. Number of one bits. Class. Elemental function. Argument. I shall be of type integer. Result Characteristics. Default integer. Result Value. The result value is equal to the number of one bits in the sequence of bits of I. The model for the interpretation of an integer value as a sequence of bits is in 13.3. 13.7.129 POPPAR (I) Description. Parity expressed as 0 or 1. Class. Elemental function. Argument. I shall be of type integer. Result Characteristics. Default integer. Result Value. POPPAR (I) has the value 1 if POPCNT (I) is odd, and 0 if POPCNT (I) is even. * * * For completeness: Fortran 2008 and also the HPF standard also list the following "Array Reduction Functions" (HPF): - IALL - Bitwise AND of all the elements of ARRAY along dimension DIM corresponding to the true elements of the mask - IANY - Bitwise OR of all the elements of ARRAY along dimension DIM corresponding to the true elements of MASK. - IPARITY - Bitwise exclusive OR of all the elements of ARRAY along dimension DIM corresponding to the true elements of MASK. - PARITY - True if and only if an odd number of values are true in MASK along dimension DIM. And Fortran 2008 also the following elemental procedures for bits: - DSHIFTL(I,J,SHIFT) - Combined left shift - DSHIFTR(I,J,SHIFT) - Combined right shift - SHIFTA - Right shift with fill. - SHIFTL - Left shift - SHIFTR - Right shift - MASKL Left justified mask - MASKR - Right justified mask - BGE - True if and only if I is bitwise greater than or equal to J - BGT - True if and only if I is bitwise greater than J. - BLE - True if and only if I is bitwise less than or equal to J - BLT - True if and only if I is bitwise less than J. - MERGE_BITS - Merge of bits under mask

Tobias, Steven, If you would like to usurp this request and use it to implement the complete set of F2008 bit intrinsics, please feel free to do so. For completeness, one other HPF bit intrinsic is ILEN - which counts the number of bits needed to represent an integer. This is not in the F2008 draft, but is occasionally useful. A few comments on the draft F2008 intrinsics: DSHIFTL/DSHIFTR - Cray-1 intrinsics. Occasionally handy. Represented the hardware vector "snake" instruction. SHIFTA - Lots of systems have this instruction in hardware, but not the Cray-1. So it went into the Cray compilers somewhat later. SHIFTL/SHIFTR - Cray-1 intrinsics. Better than ISHFT because the compiler always knows which shift instruction to generate. MASKL/MASKR - Shades of the MASK intrinsic on 60-bit CDC systems, which represented a hardware instruction. MERGE_BITS - On the Cray-1, it was called CSMG. Hardware instruction. One final instrinsic: IBCHNG. This was part of the old "Industrial Real-Time Fortran" Standard. IBCHNG allows the caller to 'flip' a specific bit to its complement. The IRTF bit intrinsics were the basis for the Milspec-1753 bit intrinsics, and then F90. But somehow IBCHNG got lost along the way. Nonetheless, a number of compilers (ifort, cray, sun, sgi, probably ibm, etc) also implement IBCHNG. (We could talk about the IRTF ISHL (logical shift), ISHA (arithmetic shift), and ISHC (circular shift) which are also implemented in some compilers. But since the F90 ISHFT and ISHFTC, and F2008 SHIFTA cover these cases in a Standard-conforming way, I would not recommend implementing them in gfortran.)

About POPCNT and POPPAR, beware! Implementations are much harder than simply using the GCC __builtin_popcount{,l,ll}: see PR40019 for similar issue with LEADZ and TRAILZ.

I'm not working on this => unassign.

(In reply to comment #3) > About POPCNT and POPPAR, beware! Implementations are much harder than simply > using the GCC __builtin_popcount{,l,ll} Well, the difference is that one should be able to easily handle 128 bit values at TREE level using __builtin_popcount ((unsigned long) X) + __builtin_popcount((unsigned long) X << 64) and __builtin_parity ((unsigned long) X) != __builtin_parity ((unsigned long) X << 64) The proper solution is too add them as new builtins to gcc/libgcc2.{c,h}; cf. libgcc/Makefile.in - and update the docs. At the same time, one could move CTZ/CLZ also to libgcc2.c, cf. http://gcc.gnu.org/viewcvs/trunk/libgfortran/intrinsics/bit_intrinsics.c?view=markup

I did LEADZ and TRAILZ, I guess I should do these. Assigning to me.

(In reply to comment #6) > I did LEADZ and TRAILZ, I guess I should do these. Assigning to me. Do you plan to do it via libgcc/Makefile.in + gcc/libgcc2.c - and then use the ME builtin?

(In reply to comment #7) > Do you plan to do it via libgcc/Makefile.in + gcc/libgcc2.c - and then use the > ME builtin? That could be fun to try :)

Patch submitted at http://gcc.gnu.org/ml/fortran/2010-08/msg00476.html

Subject: Bug 38282 Author: fxcoudert Date: Tue Aug 31 18:56:46 2010 New Revision: 163691 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=163691 Log: PR fortran/38282 * f95-lang.c (gfc_init_builtin_functions): Define popcount{,l,ll} and parity{,l,ll} builtins. * trans-intrinsic.c (gfc_conv_intrinsic_popcnt_poppar): New function. (gfc_conv_intrinsic_function): Call above new functions. * simplify.c (gfc_simplify_popcnt, gfc_simplify_poppar): New functions. * intrinsic.texi: Document POPCNT and POPPAR. * gfortran.dg/popcnt_poppar_1.F90: New test. * gfortran.dg/popcnt_poppar_2.F90: New test. Added: trunk/gcc/testsuite/gfortran.dg/popcnt_poppar_1.F90 trunk/gcc/testsuite/gfortran.dg/popcnt_poppar_2.F90 Modified: trunk/gcc/fortran/ChangeLog trunk/gcc/fortran/f95-lang.c trunk/gcc/fortran/gfortran.h trunk/gcc/fortran/intrinsic.c trunk/gcc/fortran/intrinsic.h trunk/gcc/fortran/intrinsic.texi trunk/gcc/fortran/simplify.c trunk/gcc/fortran/trans-intrinsic.c trunk/gcc/testsuite/ChangeLog

Subject: Bug 38282 Author: burnus Date: Mon Sep 6 05:55:10 2010 New Revision: 163898 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=163898 Log: 2010-09-06 Tobias Burnus <burnus@net-b.de> PR fortran/38282 * intrinsic.c (add_functions): Support IALL, IANY, IPARITY. (check_specific): Special case for those intrinsics. * gfortran.h (gfc_isym_id): Add new intrinsics * intrinsic.h (gfc_check_transf_bit_intrins, gfc_simplify_iall, gfc_simplify_iany, gfc_simplify_iparity, gfc_resolve_iall, gfc_resolve_iany, gfc_resolve_iparity): New prototypes. * iresolve.c (gfc_resolve_iall, gfc_resolve_iany, gfc_resolve_iparity, resolve_transformational): New functions. (gfc_resolve_product, gfc_resolve_sum, gfc_resolve_parity): Use resolve_transformational. * check.c (gfc_check_transf_bit_intrins): New function. * simplify.c (gfc_simplify_iall, gfc_simplify_iany, gfc_simplify_iparity, do_bit_any, do_bit_ior, do_bit_xor, simplify_transformation): New functions. (gfc_simplify_all, gfc_simplify_any, gfc_simplify_parity, gfc_simplify_sum, gfc_simplify_product): Use simplify_transformation. * trans-intrinsic.c (gfc_conv_intrinsic_arith, gfc_conv_intrinsic_function, gfc_is_intrinsic_libcall): Handle IALL, IANY and IPARITY intrinsics. * intrinsic.texi (IMAGE_INDEX): Move up to fix alphabetic order. (IALL, IANY, IPARITY): Document new intrinsics. 2010-09-06 Tobias Burnus <burnus@net-b.de> PR fortran/38282 * gfortran.dg/iall_iany_iparity_1.f90: New. * gfortran.dg/iall_iany_iparity_2.f90: New. 2010-09-06 Tobias Burnus <burnus@net-b.de> PR fortran/38282 * gfortran.map: Add new iany, iall and iparity intrinsics. * Makefile.am: Ditto. * m4/iany.m4: New. * m4/iall.m4: New. * m4/iparity.m4: New. * Makefile.in: Regenerate. * generated/iall_i1.c: Generate. * generated/iall_i2.c: Generate. * generated/iall_i4.c: Generate. * generated/iall_i8.c: Generate. * generated/iall_i16.c: Generate. * generated/iany_i1.c: Generate. * generated/iany_i2.c: Generate. * generated/iany_i4.c: Generate. * generated/iany_i8.c: Generate. * generated/iany_i16.c: Generate. * generated/iparity_i1.c: Generate. * generated/iparity_i2.c: Generate. * generated/iparity_i4.c: Generate. * generated/iparity_i8.c: Generate. * generated/iparity_i16.c: Generate. Added: trunk/gcc/testsuite/gfortran.dg/iall_iany_iparity_1.f90 trunk/gcc/testsuite/gfortran.dg/iall_iany_iparity_2.f90 trunk/libgfortran/generated/iall_i1.c trunk/libgfortran/generated/iall_i16.c trunk/libgfortran/generated/iall_i2.c trunk/libgfortran/generated/iall_i4.c trunk/libgfortran/generated/iall_i8.c trunk/libgfortran/generated/iany_i1.c trunk/libgfortran/generated/iany_i16.c trunk/libgfortran/generated/iany_i2.c trunk/libgfortran/generated/iany_i4.c trunk/libgfortran/generated/iany_i8.c trunk/libgfortran/generated/iparity_i1.c trunk/libgfortran/generated/iparity_i16.c trunk/libgfortran/generated/iparity_i2.c trunk/libgfortran/generated/iparity_i4.c trunk/libgfortran/generated/iparity_i8.c trunk/libgfortran/m4/iall.m4 trunk/libgfortran/m4/iany.m4 trunk/libgfortran/m4/iparity.m4 Modified: trunk/gcc/fortran/ChangeLog trunk/gcc/fortran/check.c trunk/gcc/fortran/gfortran.h trunk/gcc/fortran/intrinsic.c trunk/gcc/fortran/intrinsic.h trunk/gcc/fortran/intrinsic.texi trunk/gcc/fortran/iresolve.c trunk/gcc/fortran/simplify.c trunk/gcc/fortran/trans-intrinsic.c trunk/gcc/testsuite/ChangeLog trunk/libgfortran/ChangeLog trunk/libgfortran/Makefile.am trunk/libgfortran/Makefile.in trunk/libgfortran/gfortran.map

DONE: - POPPAR, POPCNT [and LEADZ/TAILZ already in GCC 4.4] - IALL, IANY, IPARITY TODO (cf. comment 2) a) F2008's bit intrinsics: DSHIFTL, DSHIFTR, SHIFTA, SHIFTL, SHIFTR, MASKL, MASKR, BGE, BGT, BLE, BLT, MERGE_BITS c) HPF only: ILEN(I) Cf. http://wotug.org/parallel/standards/hpf/, HPF 2.0, Section 7.6 d) IBCHNG(POS, I) Industrial Real-Time Fortran Standard (ISO 7846:1985; withdrawn) and common vendor extension

Subject: Bug 38282 Author: fxcoudert Date: Wed Sep 8 19:35:35 2010 New Revision: 164021 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=164021 Log: PR fortran/38282 * intrinsic.c (add_functions): Add B{G,L}{E,T}, DSHIFT{L,R}, MASK{L,R}, MERGE_BITS and SHIFT{A,L,R}. * gfortran.h: Define ISYM values for above intrinsics. * intrinsic.h (gfc_check_bge_bgt_ble_blt, gfc_check_dshift, gfc_check_mask, gfc_check_merge_bits, gfc_check_shift, gfc_simplify_bge, gfc_simplify_bgt, gfc_simplify_ble, gfc_simplify_blt, gfc_simplify_dshiftl, gfc_simplify_dshiftr, gfc_simplify_lshift, gfc_simplify_maskl, gfc_simplify_maskr, gfc_simplify_merge_bits, gfc_simplify_rshift, gfc_simplify_shifta, gfc_simplify_shiftl, gfc_simplify_shiftr, gfc_resolve_dshift, gfc_resolve_mask, gfc_resolve_merge_bits, gfc_resolve_shift): New prototypes. * iresolve.c (gfc_resolve_dshift, gfc_resolve_mask, gfc_resolve_merge_bits, gfc_resolve_shift): New functions. * check.c (gfc_check_bge_bgt_ble_blt, gfc_check_dshift, gfc_check_mask, gfc_check_merge_bits, gfc_check_shift): New functions. * trans-intrinsic.c (gfc_conv_intrinsic_dshift, gfc_conv_intrinsic_bitcomp, gfc_conv_intrinsic_shift, gfc_conv_intrinsic_merge_bits, gfc_conv_intrinsic_mask): New functions. (gfc_conv_intrinsic_function): Call above static functions. * intrinsic.texi: Document new intrinsics. * simplify.c (gfc_simplify_bge, gfc_simplify_bgt, gfc_simplify_ble, gfc_simplify_blt, gfc_simplify_dshiftl, gfc_simplify_dshiftr, gfc_simplify_lshift, gfc_simplify_maskl, gfc_simplify_maskr, gfc_simplify_merge_bits, gfc_simplify_rshift, gfc_simplify_shifta, gfc_simplify_shiftl, gfc_simplify_shiftr): New functions. * gfortran.dg/bit_comparison_1.F90: New test. * gfortran.dg/leadz_trailz_3.f90: New test. * gfortran.dg/masklr_2.F90: New test. * gfortran.dg/shiftalr_1.F90: New test. * gfortran.dg/merge_bits_2.F90: New test. * gfortran.dg/dshift_2.F90: New test. * gfortran.dg/bit_comparison_2.F90: New test. * gfortran.dg/masklr_1.F90: New test. * gfortran.dg/merge_bits_1.F90: New test. * gfortran.dg/dshift_1.F90: New test. * gfortran.dg/shiftalr_2.F90: New test. Added: trunk/gcc/testsuite/gfortran.dg/bit_comparison_1.F90 trunk/gcc/testsuite/gfortran.dg/bit_comparison_2.F90 trunk/gcc/testsuite/gfortran.dg/dshift_1.F90 trunk/gcc/testsuite/gfortran.dg/dshift_2.F90 trunk/gcc/testsuite/gfortran.dg/leadz_trailz_3.f90 trunk/gcc/testsuite/gfortran.dg/masklr_1.F90 trunk/gcc/testsuite/gfortran.dg/masklr_2.F90 trunk/gcc/testsuite/gfortran.dg/merge_bits_1.F90 trunk/gcc/testsuite/gfortran.dg/merge_bits_2.F90 trunk/gcc/testsuite/gfortran.dg/shiftalr_1.F90 trunk/gcc/testsuite/gfortran.dg/shiftalr_2.F90 Modified: trunk/gcc/fortran/ChangeLog trunk/gcc/fortran/check.c trunk/gcc/fortran/gfortran.h trunk/gcc/fortran/intrinsic.c trunk/gcc/fortran/intrinsic.h trunk/gcc/fortran/intrinsic.texi trunk/gcc/fortran/iresolve.c trunk/gcc/fortran/simplify.c trunk/gcc/fortran/trans-intrinsic.c trunk/gcc/testsuite/ChangeLog

Possible remaining are only old extensions, not sure they're useful: ILEN and IBCHNG. Closing?

Subject: Re: Bit intrinsics: ILEN and IBCHNG FX wrote: >------- Comment #14 from fxcoudert at gcc dot gnu dot org 2010-09-08 19:52 ------- >Possible remaining are only old extensions, not sure they're useful: ILEN and >IBCHNG. > >Closing? It is easy to write ones own IBCHNG. So at this point, especially given its rarity in actual codes, it is probably not worth implementing. ILEN is pretty easy to write too. If there is ever a move to implement more of HPFs intrinsics, you could add it then. (Speaking of which, I think some kind of intrinsic sorting/grading routines, like maybe simplified 1-D versions of HPFs SORT_{UP,DOWN} and GRADE_{UP,DOWN} functions would be incredibly useful to a lot of programmers. But that is something which should be covered under a different ticket.)

Fixed on 4.6 branch a while back.