[Bug target/99437] New: Error: immediate value out of range 1 to 8 at operand 3 -- `shrn v1.8b,v1.8h,15'

[Bug target/99437] New: Error: immediate value out of range 1 to 8 at operand 3 -- `shrn v1.8b,v1.8h,15'

[raj.khem at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99437

            Bug ID: 99437
           Summary: Error: immediate value out of range 1 to 8 at operand
                    3 -- `shrn v1.8b,v1.8h,15'
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: raj.khem at gmail dot com
  Target Milestone: ---

Created attachment 50321
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=50321&action=edit
test case

gcc 11 fails to build openCV for aarch64 due to an assembler error on attached
sample program.

% arch64-yoe-linux-g++ -c a.cpp -O

/tmp/ccxRnB71.s: Assembler messages:
/tmp/ccxRnB71.s:113: Error: immediate value out of range 1 to 8 at operand 3 --
`shrn v1.8b,v1.8h,15'
/tmp/ccxRnB71.s:249: Error: immediate value out of range 1 to 8 at operand 3 --
`shrn v1.8b,v1.8h,14'
/tmp/ccxRnB71.s:385: Error: immediate value out of range 1 to 8 at operand 3 --
`shrn v1.8b,v1.8h,13'
/tmp/ccxRnB71.s:521: Error: immediate value out of range 1 to 8 at operand 3 --
`shrn v1.8b,v1.8h,12'
/tmp/ccxRnB71.s:657: Error: immediate value out of range 1 to 8 at operand 3 --
`shrn v1.8b,v1.8h,11'
/tmp/ccxRnB71.s:793: Error: immediate value out of range 1 to 8 at operand 3 --
`shrn v1.8b,v1.8h,10'
/tmp/ccxRnB71.s:929: Error: immediate value out of range 1 to 8 at operand 3 --
`shrn v1.8b,v1.8h,9'

[Bug target/99437] Error: immediate value out of range 1 to 8 at operand 3 -- `shrn v1.8b,v1.8h,15'

[raj.khem at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99437

--- Comment #1 from Khem Raj <raj.khem at gmail dot com> ---
the version of gcc in use is

gcc version 11.0.1 20210306 (experimental) (GCC)

[Bug target/99437] [11 Regression] Error: immediate value out of range 1 to 8 at operand 3 -- `shrn v1.8b,v1.8h,15'

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99437

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|Error: immediate value out  |[11 Regression] Error:
                   |of range 1 to 8 at operand  |immediate value out of
                   |3 -- `shrn v1.8b,v1.8h,15'  |range 1 to 8 at operand 3
                   |                            |-- `shrn v1.8b,v1.8h,15'
   Target Milestone|---                         |11.0
           Keywords|                            |assemble-failure
               Host|x86_64                      |

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
//(insn 148 147 149 (set (reg:V16QI 33 v1 [orig:153 _101 ] [153])
//        (vec_concat:V16QI (truncate:V8QI (lshiftrt:V8HI (reg:V8HI 33 v1
[orig:165 _113 ] [165])
//                    (const_vector:V8HI [
//                            (const_int 15 [0xf]) repeated x8
//                        ])))
//            (const_vector:V8QI [
//                    (const_int 0 [0]) repeated x8
//                ])))
"/mnt/b/yoe/master/build/tmp/work/cortexa57-yoe-linux/opencv/4.5.1-r0/recipe-sysroot-native/usr/lib/aarch64-yoe-linux/gcc/aarch64-yoe-linux/11.0.1/include/arm_neon.h":6548:53
1917 {aarch64_shrnv8hi_insn_le}
//     (nil))
        shrn    v1.8b, v1.8h, 15        // 148  [c=4 l=4] 
aarch64_shrnv8hi_insn_le

Confirmed, reducing ....

[Bug target/99437] [11 Regression] Error: immediate value out of range 1 to 8 at operand 3 -- `shrn v1.8b,v1.8h,15'

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99437

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2021-03-07
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Trying 144, 146 -> 148:
  144: r159:V8HI=r165:V8HI 0>>const_vector
      REG_DEAD r165:V8HI
  146: r155:V8QI=trunc(r159:V8HI)
      REG_DEAD r159:V8HI
  148: r153:V16QI=vec_concat(r155:V8QI,const_vector)
      REG_DEAD r155:V8QI
Successfully matched this instruction:
(set (reg:V16QI 153 [ _101 ])
    (vec_concat:V16QI (truncate:V8QI (lshiftrt:V8HI (reg:V8HI 165 [ _113 ])
                (const_vector:V8HI [
                        (const_int 15 [0xf]) repeated x8
                    ])))
        (const_vector:V8QI [
                (const_int 0 [0]) repeated x8
            ])))

I have not reduced it yet but the above shows where the problem is introduced
inside combine.  I think the constrants/predicates for aarch64_shrnv8hi_insn_le
on the const_vect (shift) are incorrect.

[Bug target/99437] [11 Regression] Error: immediate value out of range 1 to 8 at operand 3 -- `shrn v1.8b,v1.8h,15'

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99437

ktkachov at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1
           Assignee|unassigned at gcc dot gnu.org      |ktkachov at gcc dot gnu.org
                 CC|                            |ktkachov at gcc dot gnu.org
             Status|NEW                         |ASSIGNED

--- Comment #4 from ktkachov at gcc dot gnu.org ---
Confirmed:
#include <arm_neon.h>

uint8x16_t
foo (uint16x8_t a, uint8x8_t b)
{
  return vcombine_u8 (vmovn_u16 (vshrq_n_u16 (a, 9)), b);
}

Testing a patch.

[Bug target/99437] [11 Regression] Error: immediate value out of range 1 to 8 at operand 3 -- `shrn v1.8b,v1.8h,15'

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99437

--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Kyrylo Tkachov <ktkachov@gcc.gnu.org>:

https://gcc.gnu.org/g:0d9a70ea3881c284b7689b691d54d047b55b486d

commit r11-7556-g0d9a70ea3881c284b7689b691d54d047b55b486d
Author: Kyrylo Tkachov <kyrylo.tkachov@arm.com>
Date:   Mon Mar 8 15:05:21 2021 +0000

    aarch64: Fix PR99437 - tighten shift predicates for narrowing shift
patterns

    In this bug combine forms the (R)SHRN(2) instructions with an invalid shift
amount.
    The intrinsic expanders for these patterns validate the right shift amount
but if the
    final patterns end up being matched by combine (or other RTL passes I
suppose) they
    still let the wrong const_vector through.

    This patch tightens up the predicates for the instructions involved by
using predicates
    for the right shift amount const_vectors.

    gcc/ChangeLog:

            PR target/99437
            * config/aarch64/predicates.md (aarch64_simd_shift_imm_vec_qi):
Define.
            (aarch64_simd_shift_imm_vec_hi): Likewise.
            (aarch64_simd_shift_imm_vec_si): Likewise.
            (aarch64_simd_shift_imm_vec_di): Likewise.
            * config/aarch64/aarch64-simd.md (aarch64_shrn<mode>_insn_le): Use
            predicate from above.
            (aarch64_shrn<mode>_insn_be): Likewise.
            (aarch64_rshrn<mode>_insn_le): Likewise.
            (aarch64_rshrn<mode>_insn_be): Likewise.
            (aarch64_shrn2<mode>_insn_le): Likewise.
            (aarch64_shrn2<mode>_insn_be): Likewise.
            (aarch64_rshrn2<mode>_insn_le): Likewise.
            (aarch64_rshrn2<mode>_insn_be): Likewise.

    gcc/testsuite/ChangeLog:

            PR target/99437
            * gcc.target/aarch64/simd/pr99437.c: New test.

[Bug target/99437] [11 Regression] Error: immediate value out of range 1 to 8 at operand 3 -- `shrn v1.8b,v1.8h,15'

[raj.khem at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99437

Khem Raj <raj.khem at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
             Status|ASSIGNED                    |RESOLVED

--- Comment #6 from Khem Raj <raj.khem at gmail dot com> ---
I can confirm that the above commit fixed the ICE