[Ecls-list] AREF/SVREF/CHAR/SCHAR/ELT and signals

[Matthew Mondor]

On Fri, 18 Mar 2011 15:26:26 -0400
Matthew Mondor <mm_lists at pulsar-zone.net> wrote:

> Attached is the test CL code and the resulting C code with ECL.
> So for the SVREF case indeed 0-1 safety levels allow better
> optimization, and ecl_aref1() is used at higher levels.

When I started looking at the array implementation, it was because I
was trying to optimize a prototype application which initially used
lists a lot.  An early test replacing a list by an array in a
particular scenario didn't seem impressive, but after more tests I can
say that indeed a significant performance gain can be achieved with
arrays.

The following example function demonstrates that ECL can generate nice
code even with AREF:


(defun test ()
  (declare (optimize (safety 0) (speed 3)))
  (let ((a (make-array 4096
                       :element-type 'ext::integer16
                       :fill-pointer nil
                       :adjustable nil)))
    (loop
       for i of-type fixnum from 0 below 4096
       do
         (setf (aref a i) i))
    a))


static cl_object 
L1test()
{
        VT2 VLEX2 CLSR2 STCK2
                        const cl_env_ptr cl_env_copy = ecl_process_env();
        cl_object       value0;
TTL:
        {
                cl_object       V1;     /* A               */
                V1 = si_make_vector(ECL_SYM("INTEGER16", 1312), MAKE_FIXNUM(4096), Cnil, Cnil, Cnil, MAKE_FIXNUM(0)) /* MAKE-VECTOR */ ;
                {
                        cl_fixnum       V2;     /* I               */
                        V2 = 0;
        L5:             ;
                        (V1)->vector.self.i16[V2] = V2;
                        V2 = (V2) + 1;
                        if (!((V2) >= (4096))) {
                                goto L12;
                        }
                        goto L6;
        L12:            ;
                        goto L10;
        L10:            ;
                        goto L5;
        L6:             ;
                        goto L2;
                }
L2:             ;
                value0 = V1;
                cl_env_copy->nvalues = 1;
                return value0;
        }
}


00000770 <L1test>:
 770:   55                      push   %ebp
 771:   b9 03 00 00 00          mov    $0x3,%ecx
 776:   89 e5                   mov    %esp,%ebp
 778:   ba 01 00 00 00          mov    $0x1,%edx
 77d:   56                      push   %esi
 77e:   be 01 00 00 00          mov    $0x1,%esi
 783:   53                      push   %ebx
 784:   e8 6c 00 00 00          call   7f5 <__i686.get_pc_thunk.bx>
 789:   81 c3 33 12 00 00       add    $0x1233,%ebx
 78f:   83 ec 20                sub    $0x20,%esp
 792:   89 4c 24 14             mov    %ecx,0x14(%esp)
 796:   b9 01 00 00 00          mov    $0x1,%ecx
 79b:   89 54 24 10             mov    %edx,0x10(%esp)
 79f:   ba 03 40 00 00          mov    $0x4003,%edx
 7a4:   89 74 24 0c             mov    %esi,0xc(%esp)
 7a8:   89 54 24 04             mov    %edx,0x4(%esp)
 7ac:   89 4c 24 08             mov    %ecx,0x8(%esp)
 7b0:   8b 83 f4 ff ff ff       mov    0xfffffff4(%ebx),%eax
 7b6:   05 80 8f 00 00          add    $0x8f80,%eax
 7bb:   89 04 24                mov    %eax,(%esp)
 7be:   e8 cd fd ff ff          call   590 <si_make_vector at plt>
 7c3:   31 d2                   xor    %edx,%edx
 7c5:   89 c6                   mov    %eax,%esi
 7c7:   89 f6                   mov    %esi,%esi
 7c9:   8d bc 27 00 00 00 00    lea    0x0(%edi),%edi
 7d0:   8b 46 10                mov    0x10(%esi),%eax
 7d3:   66 89 14 50             mov    %dx,(%eax,%edx,2)
 7d7:   42                      inc    %edx
 7d8:   81 fa 00 10 00 00       cmp    $0x1000,%edx
 7de:   75 f0                   jne    7d0 <L1test+0x60>
 7e0:   e8 db fd ff ff          call   5c0 <ecl_process_env at plt>
 7e5:   c7 40 04 01 00 00 00    movl   $0x1,0x4(%eax)
 7ec:   83 c4 20                add    $0x20,%esp
 7ef:   89 f0                   mov    %esi,%eax
 7f1:   5b                      pop    %ebx
 7f2:   5e                      pop    %esi
 7f3:   5d                      pop    %ebp
 7f4:   c3                      ret    


Thanks for making this possible,
-- 
Matt