[Bug target/63615] New: [i686][5 Regression] FAIL: gcc.target/i386/addr-sel-1.c

[Bug target/63615] New: [i686][5 Regression] FAIL: gcc.target/i386/addr-sel-1.c

[izamyatin at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63615

            Bug ID: 63615
           Summary: [i686][5 Regression] FAIL:
                    gcc.target/i386/addr-sel-1.c
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: izamyatin at gmail dot com
            Target: i686

There is a new fail for gcc.target/i386/addr-sel-1.c on i686 after r216462

For this test we now have in asm file

        movl    4(%esp), %eax
        leal    1(%eax), %edx
        movsbl  a(%edx), %ecx
        movsbl  b(%edx), %eax
        addl    %ecx, %eax
        ret


instead of earlier

        movl    4(%esp), %eax
        movsbl  a+1(%eax), %ecx
        movsbl  b+1(%eax), %eax
        addl    %ecx, %eax
        ret

Seems the change resticts some opts in postreload. Now in .postreload there are 

(insn 6 21 8 2 (parallel [
              (set (reg:SI 1 dx [orig:83 D.1733 ] [83])
                  (plus:SI (reg:SI 0 ax [96])
                      (const_int 1 [0x1])))
              (clobber (reg:CC 17 flags))
          ]) ../gcc/testsuite/gcc.target/i386/addr-sel-1.c:13 220 {*addsi_1}
       (nil))
(insn 8 6 10 2 (set (reg:SI 2 cx [orig:93 D.1733 ] [93])
          (sign_extend:SI (mem/j:QI (plus:SI (reg:SI 1 dx [orig:83 D.1733 ]
[83])
                      (symbol_ref:SI ("a")  <var_decl 0x7f7b4a70fc60 a>)) [0 a
S1 A8]))) ../gcc/testsuite/gcc.target/i386/addr-sel-1.c:13 148 {extendqisi2}
       (nil))

while earlier there were

(insn 6 21 8 2 (parallel [
            (set (reg:SI 1 dx [orig:83 D.1733 ] [83])
                (plus:SI (reg:SI 0 ax [96])
                    (const_int 1 [0x1])))
            (clobber (reg:CC 17 flags))
        ]) addr-sel-1-good.c:13 220 {*addsi_1}
     (nil))
(insn 8 6 10 2 (set (reg:SI 2 cx [orig:93 D.1733 ] [93])
        (sign_extend:SI (mem/j:QI (plus:SI (reg:SI 0 ax [96])
                    (const:SI (plus:SI (symbol_ref:SI ("a")  <var_decl
0x7fbf3c296c60 a>)
                            (const_int 1 [0x1])))) [0 a S1 A8])))
addr-sel-1-good.c:13 148 {extendqisi2}
     (nil))

so insn 6 is not needed

[Bug target/63615] [5 Regression] FAIL: gcc.target/i386/addr-sel-1.c

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63615

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |amodra at gcc dot gnu.org,
                   |                            |jakub at gcc dot gnu.org
   Target Milestone|---                         |5.0
            Summary|[i686][5 Regression] FAIL:  |[5 Regression] FAIL:
                   |gcc.target/i386/addr-sel-1. |gcc.target/i386/addr-sel-1.
                   |c                           |c

[Bug target/63615] [5 Regression] FAIL: gcc.target/i386/addr-sel-1.c

[amodra at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63615

Alan Modra <amodra at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2014-10-23
                 CC|amodra at gcc dot gnu.org          |amodra at gmail dot com
           Assignee|unassigned at gcc dot gnu.org      |amodra at gmail dot com
     Ever confirmed|0                           |1

--- Comment #1 from Alan Modra <amodra at gmail dot com> ---
Investigating

[Bug target/63615] [5 Regression] FAIL: gcc.target/i386/addr-sel-1.c

[amodra at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63615

--- Comment #2 from Alan Modra <amodra at gmail dot com> ---
Breakpoint 1, simplify_plus_minus (code=code@entry=PLUS,
mode=mode@entry=SImode, op0=op0@entry=0x7ffff6d4b558,
op1=op1@entry=0x7ffff6d483a8) at /src/gcc-virgin/gcc/simplify-rtx.c:3967
(gdb) p debug_rtx(op0)
(plus:SI (reg:SI 0 ax [96])
    (const_int 1 [0x1]))
$1 = void
(gdb) p debug_rtx(op1)
(symbol_ref:SI ("a") <var_decl 0x7ffff6c2f900 a>)
$2 = void

Believe it or not, this PR is due to fixing the accounting of n_constants. 
Previously seeing n_constants > 1 (which is wrong, there is only one int
constant above) set "canonicalized".  Now, nothing sets "canonicalized" and
simplify_plus_minus exits with NULL.

[Bug rtl-optimization/63615] [5 Regression] FAIL: gcc.target/i386/addr-sel-1.c

[amodra at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63615

--- Comment #3 from Alan Modra <amodra at gcc dot gnu.org> ---
Author: amodra
Date: Sat Oct 25 06:45:52 2014
New Revision: 216689

URL: https://gcc.gnu.org/viewcvs?rev=216689&root=gcc&view=rev
Log:
    PR rtl-optimization/63615
    * simplify-rtx.c (simplify_plus_minus): Set "canonicalized" on
    decomposing PLUS or MINUS if operands are not placed adjacent
    in the "ops" array.


Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/simplify-rtx.c

[Bug rtl-optimization/63615] [5 Regression] FAIL: gcc.target/i386/addr-sel-1.c

[amodra at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63615

Alan Modra <amodra at gmail dot com> changed:

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

--- Comment #4 from Alan Modra <amodra at gmail dot com> ---
Fixed