Re: MPS codegen

["Gerd Möllmann" <gerd.moellmann@gmail.com>]

Gerd Möllmann <gerd.moellmann@gmail.com> writes:

> Helmut Eller <eller.helmut@gmail.com> writes:
>
>>> I think the thing I don't like is that I believe there should be only
>>> one description of an object's layout. Be it C (struct), or be it
>>> somethings else, from which C is generated.
>>
>> Sure, but that's easier said than done.
>
> Yeah :-). Too bad that GCC doesn't have something like Clang's Python
> API. Somehow I don't really believe in tree-sitter for this specific
> purpose. But what do I know...
>
>> BTW, the MPS documentation says that mps_reserve allocates a block.  In
>> MPS, a block is not necessarily a single object.  One possible
>> interpretation of this could be that mps_reserve can be used to allocate
>> a block that contains many objects.  Perhaps we could use a single block
>> for the entire dump?  E.g. implement a version of dump_mmap_contiguous
>> that uses mps_reserve.  What's your interpretation?
>
> The same. I think I've read somewhere that anything goes in such a block
> as long as the object format can cope with it.
>
> OTOH, on my machine, the whole copying of the dump to MPS, mirroring and
> redirecting roots takes ca. 38ms ATM. Where the copying and mirroring
> are the two main contributors and take about the same time. Maybe
> there's not much to win.

Here's what it prints, times can vary a bit

/Users/gerd/emacs/github/igc % IGC_MIRROR_STATS=1 src/emacs -Q
--------------------------------------------------
                          Type        N      Bytes
--------------------------------------------------
               IGC_OBJ_INVALID        0          0
                   IGC_OBJ_PAD        0          0
                   IGC_OBJ_FWD        0          0
                  IGC_OBJ_CONS   285532    6852768
                IGC_OBJ_SYMBOL    16268     911008
              IGC_OBJ_INTERVAL       31       1984
                IGC_OBJ_STRING    62964    2518560
           IGC_OBJ_STRING_DATA    62964    2237944
                IGC_OBJ_VECTOR    41660    6023960
           IGC_OBJ_VECTOR_WEAK        5        208
            IGC_OBJ_ITREE_TREE        0          0
            IGC_OBJ_ITREE_NODE        4        352
                 IGC_OBJ_IMAGE        0          0
           IGC_OBJ_IMAGE_CACHE        0          0
                  IGC_OBJ_FACE        0          0
            IGC_OBJ_FACE_CACHE        0          0
                 IGC_OBJ_FLOAT      169       4056
                   IGC_OBJ_BLV      164       7872
               IGC_OBJ_PTR_VEC        0          0
               IGC_OBJ_OBJ_VEC        0          0
              IGC_OBJ_HASH_VEC      528     376528
               IGC_OBJ_HANDLER        0          0
                 IGC_OBJ_BYTES        0          0
        IGC_OBJ_BUILTIN_SYMBOL        0          0
        IGC_OBJ_BUILTIN_THREAD        0          0
          IGC_OBJ_BUILTIN_SUBR        0          0
--------------------------------------------------
                          Type        N      Bytes
--------------------------------------------------
            PVEC_NORMAL_VECTOR    29569    1588104
                     PVEC_FREE        0          0
                   PVEC_BIGNUM        0          0
                   PVEC_MARKER       18        864
                  PVEC_OVERLAY        4        160
                PVEC_FINALIZER        0          0
          PVEC_SYMBOL_WITH_POS        0          0
                 PVEC_MISC_PTR        0          0
                 PVEC_USER_PTR        0          0
                  PVEC_PROCESS        0          0
                    PVEC_FRAME        1        592
                   PVEC_WINDOW        2       1088
              PVEC_BOOL_VECTOR      340      13600
                   PVEC_BUFFER        6       6000
               PVEC_HASH_TABLE      322      28336
                 PVEC_TERMINAL        0          0
     PVEC_WINDOW_CONFIGURATION        0          0
                     PVEC_SUBR        0          0
                  PVEC_PACKAGE       24       1728
                    PVEC_OTHER        0          0
                  PVEC_XWIDGET        0          0
             PVEC_XWIDGET_VIEW        0          0
                   PVEC_THREAD        0          0
                    PVEC_MUTEX        0          0
                  PVEC_CONDVAR        0          0
          PVEC_MODULE_FUNCTION        0          0
  PVEC_MODULE_GLOBAL_REFERENCE        0          0
         PVEC_NATIVE_COMP_UNIT        0          0
                PVEC_TS_PARSER        0          0
                  PVEC_TS_NODE        0          0
        PVEC_TS_COMPILED_QUERY        0          0
                   PVEC_SQLITE        0          0
                  PVEC_CLOSURE     6585     372048
               PVEC_CHAR_TABLE       80      45864
           PVEC_SUB_CHAR_TABLE     4305    3941400
                   PVEC_RECORD      402      23936
                     PVEC_FONT        2        240
--------------------------------------------------
                         Total   470289   18935240
--------------------------------------------------
           Copy objects to MPS   0.0197s
             Mirror references   0.0152s
                Redirect roots   0.0001s
                    Total time   0.0351s