[Bug target/56315] New: ARM: Improve use of 64-bit constants in logical operations

[Bug target/56315] New: ARM: Improve use of 64-bit constants in logical operations

[josh.m.conner at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56315

             Bug #: 56315
           Summary: ARM: Improve use of 64-bit constants in logical
                    operations
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: target
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: josh.m.conner@gmail.com


In the ARM backend, support was added for recognizing addition with 64-bit
constants that could be split up into two 32-bit literals that could be handled
with immediates in the adds/adc operations.  However, this support is still not
present for the logical operations.  For example, compiling this code with -O2:

  unsigned long long or64 (unsigned long long input)
  {
    return input | 0x200000004ULL;
  }

Gives us:

    mov    r2, #4
    mov    r3, #2
    orr    r0, r0, r2
    orr    r1, r1, r3

When it could produce:

    orr    r0, r0, #4
    orr    r1, r1, #2

The same improvement could be applied to & and ^ operations as well.

[Bug target/56315] ARM: Improve use of 64-bit constants in logical operations

[rearnsha at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56315

Richard Earnshaw <rearnsha at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|                            |arm
           Priority|P3                          |P4
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-03-04
     Ever Confirmed|0                           |1

--- Comment #1 from Richard Earnshaw <rearnsha at gcc dot gnu.org> 2013-03-04 09:12:26 UTC ---
Confirmed

[Bug target/56315] ARM: Improve use of 64-bit constants in logical operations

[clyon at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56315

--- Comment #2 from clyon at gcc dot gnu.org ---
Author: clyon
Date: Thu Sep  5 12:38:03 2013
New Revision: 202280

URL: http://gcc.gnu.org/viewcvs?rev=202280&root=gcc&view=rev
Log:
gcc/
2013-09-05  Christophe Lyon  <christophe.lyon@linaro.org>

    Backport from trunk r199527,199792,199814.
    2013-05-31  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>

    PR target/56315
    * config/arm/arm.c (const_ok_for_dimode_op): Handle IOR.
    * config/arm/arm.md (*iordi3_insn): Change to insn_and_split.
    * config/arm/neon.md (iordi3_neon): Remove.
    (neon_vorr<mode>): Generate iordi3 instead of iordi3_neon.
    * config/arm/predicates.md (imm_for_neon_logic_operand):
    Move to earlier in the file.
    (neon_logic_op2): Likewise.
    (arm_iordi_operand_neon): New predicate.

    2013-06-07  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>

    * config/arm/constraints.md (Df): New constraint.
    * config/arm/arm.md (iordi3_insn): Use Df constraint instead of De.
    Correct length attribute for last two alternatives.

    2013-06-07  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>

    PR target/56315
    * config/arm/arm.md (*xordi3_insn): Change to insn_and_split.
    (xordi3): Change operand 2 constraint to arm_xordi_operand.
    * config/arm/arm.c (const_ok_for_dimode_op): Handle XOR.
    * config/arm/constraints.md (Dg): New constraint.
    * config/arm/neon.md (xordi3_neon): Remove.
    (neon_veor<mode>): Generate xordi3 instead of xordi3_neon.
    * config/arm/predicates.md (arm_xordi_operand): New predicate.

gcc/testsuite/
2013-09-05  Christophe Lyon  <christophe.lyon@linaro.org>

    Backport from trunk r199527,199814,201435.
    2013-05-31  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>

    PR target/56315
    * gcc.target/arm/iordi3-opt.c: New test.

    2013-06-07  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>

    PR target/56315
    * gcc.target/arm/xordi3-opt.c: New test.

    2013-08-02  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>

    * gcc.target/arm/neon-for-64bits-2.c: Delete.


Added:
    branches/linaro/gcc-4_8-branch/gcc/testsuite/gcc.target/arm/iordi3-opt.c
      - copied unchanged from r199527,
trunk/gcc/testsuite/gcc.target/arm/iordi3-opt.c
    branches/linaro/gcc-4_8-branch/gcc/testsuite/gcc.target/arm/xordi3-opt.c
      - copied unchanged from r199814,
trunk/gcc/testsuite/gcc.target/arm/xordi3-opt.c
Removed:
   
branches/linaro/gcc-4_8-branch/gcc/testsuite/gcc.target/arm/neon-for-64bits-2.c
Modified:
    branches/linaro/gcc-4_8-branch/   (props changed)
    branches/linaro/gcc-4_8-branch/gcc/ChangeLog.linaro
    branches/linaro/gcc-4_8-branch/gcc/config/arm/arm.c
    branches/linaro/gcc-4_8-branch/gcc/config/arm/arm.md
    branches/linaro/gcc-4_8-branch/gcc/config/arm/constraints.md
    branches/linaro/gcc-4_8-branch/gcc/config/arm/neon.md
    branches/linaro/gcc-4_8-branch/gcc/config/arm/predicates.md
    branches/linaro/gcc-4_8-branch/gcc/testsuite/ChangeLog.linaro

Propchange: branches/linaro/gcc-4_8-branch/
            ('svn:mergeinfo' modified)

[Bug target/56315] ARM: Improve use of 64-bit constants in logical operations

[ktkachov at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56315

ktkachov at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|                            |ktkachov at gcc dot gnu.org
         Resolution|---                         |FIXED

--- Comment #3 from ktkachov at gcc dot gnu.org ---
This is now fixed on trunk, most probably with r199527.

[Bug target/56315] ARM: Improve use of 64-bit constants in logical operations

[josh.m.conner at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56315

--- Comment #4 from Joshua Conner <josh.m.conner at gmail dot com> ---
Excellent - thanks!