예제 #1
0
파일: alloc.c 프로젝트: BrianSipple/julia
static jl_datatype_layout_t *jl_get_layout(uint32_t nfields,
                                           uint32_t alignment,
                                           int haspadding,
                                           jl_fielddesc32_t desc[])
{
    // compute the smallest fielddesc type that can hold the layout description
    int fielddesc_type = 0;
    if (nfields > 0) {
        uint32_t max_size = 0;
        uint32_t max_offset = desc[nfields - 1].offset;
        for (size_t i = 0; i < nfields; i++) {
            if (desc[i].size > max_size)
                max_size = desc[i].size;
        }
        jl_fielddesc8_t maxdesc8 = { 0, max_size, max_offset };
        jl_fielddesc16_t maxdesc16 = { 0, max_size, max_offset };
        jl_fielddesc32_t maxdesc32 = { 0, max_size, max_offset };
        if (maxdesc8.size != max_size || maxdesc8.offset != max_offset) {
            fielddesc_type = 1;
            if (maxdesc16.size != max_size || maxdesc16.offset != max_offset) {
                fielddesc_type = 2;
                if (maxdesc32.size != max_size || maxdesc32.offset != max_offset) {
                    assert(0); // should have been verified by caller
                }
            }
        }
    }

    // allocate a new descriptor
    uint32_t fielddesc_size = jl_fielddesc_size(fielddesc_type);
    jl_datatype_layout_t *flddesc =
        (jl_datatype_layout_t*)jl_gc_perm_alloc(sizeof(jl_datatype_layout_t) + nfields * fielddesc_size);
    flddesc->nfields = nfields;
    flddesc->alignment = alignment;
    flddesc->haspadding = haspadding;
    flddesc->fielddesc_type = fielddesc_type;

    // fill out the fields of the new descriptor
    jl_fielddesc8_t* desc8 = (jl_fielddesc8_t*)jl_dt_layout_fields(flddesc);
    jl_fielddesc16_t* desc16 = (jl_fielddesc16_t*)jl_dt_layout_fields(flddesc);
    jl_fielddesc32_t* desc32 = (jl_fielddesc32_t*)jl_dt_layout_fields(flddesc);
    int ptrfree = 1;
    for (size_t i = 0; i < nfields; i++) {
        if (fielddesc_type == 0) {
            desc8[i].offset = desc[i].offset;
            desc8[i].size = desc[i].size;
            desc8[i].isptr = desc[i].isptr;
        }
        else if (fielddesc_type == 1) {
            desc16[i].offset = desc[i].offset;
            desc16[i].size = desc[i].size;
            desc16[i].isptr = desc[i].isptr;
        }
        else {
            desc32[i].offset = desc[i].offset;
            desc32[i].size = desc[i].size;
            desc32[i].isptr = desc[i].isptr;
        }
        if (desc[i].isptr)
            ptrfree = 0;
    }
    flddesc->pointerfree = ptrfree;
    return flddesc;
}
예제 #2
0
파일: datatype.c 프로젝트: helgee/julia
static jl_datatype_layout_t *jl_get_layout(uint32_t nfields,
                                           uint32_t alignment,
                                           int haspadding,
                                           jl_fielddesc32_t desc[])
{
    // compute the smallest fielddesc type that can hold the layout description
    int fielddesc_type = 0;
    uint32_t npointers = 0;
    // First pointer field
    uint32_t first_ptr = (uint32_t)-1;
    // Last pointer field
    uint32_t last_ptr = 0;
    if (nfields > 0) {
        uint32_t max_size = 0;
        uint32_t max_offset = desc[nfields - 1].offset;
        for (size_t i = 0; i < nfields; i++) {
            if (desc[i].size > max_size)
                max_size = desc[i].size;
            if (desc[i].isptr) {
                npointers++;
                if (first_ptr == (uint32_t)-1)
                    first_ptr = i;
                last_ptr = i;
            }
        }
        jl_fielddesc8_t maxdesc8 = { 0, max_size, max_offset };
        jl_fielddesc16_t maxdesc16 = { 0, max_size, max_offset };
        jl_fielddesc32_t maxdesc32 = { 0, max_size, max_offset };
        if (maxdesc8.size != max_size || maxdesc8.offset != max_offset) {
            fielddesc_type = 1;
            if (maxdesc16.size != max_size || maxdesc16.offset != max_offset) {
                fielddesc_type = 2;
                if (maxdesc32.size != max_size || maxdesc32.offset != max_offset) {
                    assert(0); // should have been verified by caller
                }
            }
        }
    }

    // allocate a new descriptor
    uint32_t fielddesc_size = jl_fielddesc_size(fielddesc_type);
    int has_padding = nfields && npointers;
    jl_datatype_layout_t *flddesc =
        (jl_datatype_layout_t*)jl_gc_perm_alloc(sizeof(jl_datatype_layout_t) +
                                                nfields * fielddesc_size +
                                                (has_padding ? sizeof(uint32_t) : 0), 0, 4, 0);
    if (has_padding) {
        if (first_ptr > UINT16_MAX)
            first_ptr = UINT16_MAX;
        last_ptr = nfields - last_ptr - 1;
        if (last_ptr > UINT16_MAX)
            last_ptr = UINT16_MAX;
        flddesc = (jl_datatype_layout_t*)(((char*)flddesc) + sizeof(uint32_t));
        jl_datatype_layout_n_nonptr(flddesc) = (first_ptr << 16) | last_ptr;
    }
    flddesc->nfields = nfields;
    flddesc->alignment = alignment;
    flddesc->haspadding = haspadding;
    flddesc->fielddesc_type = fielddesc_type;

    // fill out the fields of the new descriptor
    jl_fielddesc8_t* desc8 = (jl_fielddesc8_t*)jl_dt_layout_fields(flddesc);
    jl_fielddesc16_t* desc16 = (jl_fielddesc16_t*)jl_dt_layout_fields(flddesc);
    jl_fielddesc32_t* desc32 = (jl_fielddesc32_t*)jl_dt_layout_fields(flddesc);
    for (size_t i = 0; i < nfields; i++) {
        if (fielddesc_type == 0) {
            desc8[i].offset = desc[i].offset;
            desc8[i].size = desc[i].size;
            desc8[i].isptr = desc[i].isptr;
        }
        else if (fielddesc_type == 1) {
            desc16[i].offset = desc[i].offset;
            desc16[i].size = desc[i].size;
            desc16[i].isptr = desc[i].isptr;
        }
        else {
            desc32[i].offset = desc[i].offset;
            desc32[i].size = desc[i].size;
            desc32[i].isptr = desc[i].isptr;
        }
    }
    uint32_t nexp = 0;
    while (npointers >= 0x10000) {
        nexp++;
        npointers = npointers >> 1;
    }
    flddesc->npointers = npointers | (nexp << 16);
    return flddesc;
}