diff options
author | Raymond Lu <songyulu@hdfgroup.org> | 2004-03-13 17:39:41 (GMT) |
---|---|---|
committer | Raymond Lu <songyulu@hdfgroup.org> | 2004-03-13 17:39:41 (GMT) |
commit | 95dc09ab4b7d20f971cc26a91dbf2df46f71bb96 (patch) | |
tree | cd5bfd0ab985801566fad6c3e1a26c82af08c37d /src/H5Tconv.c | |
parent | f0ac5a6420d53f3c2ce4a322f3d6e36902b67b42 (diff) | |
download | hdf5-95dc09ab4b7d20f971cc26a91dbf2df46f71bb96.zip hdf5-95dc09ab4b7d20f971cc26a91dbf2df46f71bb96.tar.gz hdf5-95dc09ab4b7d20f971cc26a91dbf2df46f71bb96.tar.bz2 |
[svn-r8259] *** empty log message ***
Diffstat (limited to 'src/H5Tconv.c')
-rw-r--r-- | src/H5Tconv.c | 387 |
1 files changed, 380 insertions, 7 deletions
diff --git a/src/H5Tconv.c b/src/H5Tconv.c index f6a51f1..e686faa 100644 --- a/src/H5Tconv.c +++ b/src/H5Tconv.c @@ -8472,7 +8472,7 @@ H5T_conv_f_i (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts, /* Allocate enough space for the buffer holding temporary * converted value */ - buf_size = (int)HDpow((double)2.0, (double)src.u.f.esize) / 8 + 1; + buf_size = (size_t)HDpow((double)2.0, (double)src.u.f.esize) / 8 + 1; int_buf = (uint8_t*)H5MM_calloc(buf_size); /* The conversion loop */ @@ -8564,7 +8564,6 @@ H5T_conv_f_i (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts, * the source exponent bias. */ if (0==expo || H5T_NORM_NONE==src.u.f.norm) { - /*Don't get this part*/ bitno = H5T_bit_find(s, src.u.f.mpos, src.u.f.msize, H5T_BIT_MSB, TRUE); assert(bitno>=0); @@ -8607,11 +8606,7 @@ H5T_conv_f_i (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts, * Shift mantissa part by exponent minus mantissa size(right shift), * or by mantissa size minus exponent(left shift). */ - if( H5T_NORM_IMPLIED==src.u.f.norm) { - H5T_bit_shift(int_buf, expo - src.u.f.msize, buf_size); - } else if(H5T_NORM_NONE==src.u.f.norm) { - /* How to do this? */ - } + H5T_bit_shift(int_buf, expo - src.u.f.msize, buf_size); /*fprintf(stderr, "int_buf="); for(i=0; i<buf_size; i++) @@ -8749,3 +8744,381 @@ H5T_conv_f_i (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts, done: FUNC_LEAVE_NOAPI(ret_value); } + + +/*------------------------------------------------------------------------- + * Function: H5T_conv_i_f + * + * Purpose: Convert one integer type to a floating-point type. This is + * the catch-all function for integer-float conversions and + * is probably not particularly fast. + * + * Return: Non-negative on success/Negative on failure + * + * Programmer: Raymond Lu + * Friday, Feb 6, 2004 + * + * Modifications: + * + *------------------------------------------------------------------------- + */ +herr_t +H5T_conv_i_f (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts, + size_t buf_stride, size_t UNUSED bkg_stride, void *buf, void UNUSED *bkg, + hid_t UNUSED dxpl_id) +{ + /* Traversal-related variables */ + H5T_t *src_p; /*source data type */ + H5T_t *dst_p; /*destination data type */ + H5T_atomic_t src; /*atomic source info */ + H5T_atomic_t dst; /*atomic destination info */ + int direction; /*forward or backward traversal */ + hsize_t elmtno; /*element number */ + size_t half_size; /*half the type size */ + hsize_t olap; /*num overlapping elements */ + ssize_t bitno; /*bit number */ + uint8_t *s, *sp, *d, *dp; /*source and dest traversal ptrs*/ + uint8_t dbuf[64]; /*temp destination buffer */ + + /* Conversion-related variables */ + hsize_t expo; /*destiny exponent */ + hsize_t expo_max; /*maximal possible exponent value */ + /*hsize_t sign = 0;*/ /*source sign bit value */ + /*hsize_t is_max_neg = 0;*/ /*source is maximal negative value*/ + /*hsize_t do_round = 0;*/ /*whether there is roundup */ + /*hsize_t trailing = 0;*/ /*whether there is trailing after 1st roundup bit*/ + uint8_t *int_buf; /*buffer for temporary value */ + size_t buf_size; /*buffer size for temporary value */ + size_t msize; /*mantissa size after restored implied 1 */ + size_t i; /*miscellaneous counters */ + size_t first; /*first bit(MSB) in an integer */ + ssize_t sfirst; /*a signed version of `first' */ + herr_t ret_value=SUCCEED; /* Return value */ + + FUNC_ENTER_NOAPI(H5T_conv_i_f, FAIL); + + switch (cdata->command) { + case H5T_CONV_INIT: + if (NULL==(src_p=H5I_object(src_id)) || + NULL==(dst_p=H5I_object(dst_id))) + HGOTO_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type"); + src = src_p->u.atomic; + dst = dst_p->u.atomic; + if (H5T_ORDER_LE!=dst.order && H5T_ORDER_BE!=dst.order) + HGOTO_ERROR (H5E_DATATYPE, H5E_UNSUPPORTED, FAIL, "unsupported byte order"); + if (dst_p->size>sizeof(dbuf)) + HGOTO_ERROR (H5E_DATATYPE, H5E_UNSUPPORTED, FAIL, "destination size is too large"); + if (8*sizeof(expo)-1<src.u.f.esize) + HGOTO_ERROR (H5E_DATATYPE, H5E_UNSUPPORTED, FAIL, "exponent field is too large"); + cdata->need_bkg = H5T_BKG_NO; + break; + + case H5T_CONV_FREE: + break; + + case H5T_CONV_CONV: + /* Get the data types */ + if (NULL==(src_p=H5I_object(src_id)) || + NULL==(dst_p=H5I_object(dst_id))) + HGOTO_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type"); + src = src_p->u.atomic; + dst = dst_p->u.atomic; + + /* + * Do we process the values from beginning to end or vice versa? Also, + * how many of the elements have the source and destination areas + * overlapping? + */ + if (src_p->size==dst_p->size || buf_stride) { + sp = dp = (uint8_t*)buf; + direction = 1; + olap = nelmts; + } else if (src_p->size>=dst_p->size) { + double olap_d = HDceil((double)(dst_p->size)/ + (double)(src_p->size-dst_p->size)); + olap = (size_t)olap_d; + sp = dp = (uint8_t*)buf; + direction = 1; + } else { + double olap_d = HDceil((double)(src_p->size)/ + (double)(dst_p->size-src_p->size)); + olap = (size_t)olap_d; + sp = (uint8_t*)buf + (nelmts-1) * src_p->size; + dp = (uint8_t*)buf + (nelmts-1) * dst_p->size; + direction = -1; + } + + /* Allocate enough space for the buffer holding temporary + * converted value + */ + buf_size = (src.prec > dst.u.f.msize ? src.prec : dst.u.f.msize)/8 + 1; + int_buf = (uint8_t*)H5MM_calloc(buf_size); + + /* The conversion loop */ + for (elmtno=0; elmtno<nelmts; elmtno++) { + hsize_t sign = 0; /*source sign bit value */ + hsize_t is_max_neg = 0; /*source is maximal negative value*/ + hsize_t do_round = 0; /*whether there is roundup */ + hsize_t trailing = 0; /*whether there is trailing after 1st roundup bit*/ + + /* + * If the source and destination buffers overlap then use a + * temporary buffer for the destination. + */ + if (direction>0) { + s = sp; + d = elmtno<olap ? dbuf : dp; + } else { + s = sp; + d = elmtno+olap >= nelmts ? dbuf : dp; + } +#ifndef NDEBUG + /* I don't quite trust the overlap calculations yet --rpm */ + if (d==dbuf) { + assert ((dp>=sp && dp<sp+src_p->size) || + (sp>=dp && sp<dp+dst_p->size)); + } else { + assert ((dp<sp && dp+dst_p->size<=sp) || + (sp<dp && sp+src_p->size<=dp)); + } +#endif + + /* + * Put the data in little endian order so our loops aren't so + * complicated. We'll do all the conversion stuff assuming + * little endian and then we'll fix the order at the end. + */ + if (H5T_ORDER_BE==src.order) { + half_size = src_p->size/2; + for (i=0; i<half_size; i++) { + uint8_t tmp = s[src_p->size-(i+1)]; + s[src_p->size-(i+1)] = s[i]; + s[i] = tmp; + } + } + + /*zero-set all destination bits*/ + H5T_bit_set (d, dst.offset, dst.prec, FALSE); + + /* Copy source into a temporary buffer */ + H5T_bit_copy(int_buf, 0, s, src.offset, src.prec); + + +/* For debug */ +/*HDmemset(int_buf, 0, buf_size); +H5T_bit_set(int_buf, 0, src.prec, 1);*/ + +/*fprintf(stderr, "\n no. %d int_buf=0x ", elmtno); +for(i=0; i<buf_size; i++) + fprintf(stderr, "%02x ", int_buf[i]);*/ +/*fprintf(stderr, "\n s=0x "); +for(i=0; i<buf_size-1; i++) + fprintf(stderr, "%02x ", s[i]);*/ + + /* + * Find the sign bit value of the source. + */ + if (H5T_SGN_2 == src.u.i.sign) + sign = H5T_bit_get_d(int_buf, src.prec-1, 1); + + /* + * What is the bit position(starting from 0 as first one) for the most significant + * bit(MSB) of S which is set? + */ + if(H5T_SGN_2 == src.u.i.sign) { + sfirst = H5T_bit_find(int_buf, 0, src.prec-1, H5T_BIT_MSB, TRUE); + if(sign && sfirst < 0) + /* The case 0x80...00, which is negative with maximal value */ + is_max_neg = 1; + } else if(H5T_SGN_NONE == src.u.i.sign) + sfirst = H5T_bit_find(int_buf, 0, src.prec, H5T_BIT_MSB, TRUE); +/*fprintf(stderr, "\n is_max_neg=%d", is_max_neg);*/ + + /* Handle special cases here. Integer is zero */ + if(!sign && sfirst < 0) + goto padding; + + /* + * Convert source integer if it's negative + */ + if (H5T_SGN_2 == src.u.i.sign && sign) { + if(!is_max_neg) { + /* Equivalent to ~(i - 1) */ + H5T_bit_dec(int_buf, 0, buf_size*8); + H5T_bit_neg(int_buf, 0, buf_size*8); + sfirst = H5T_bit_find(int_buf, 0, src.prec-1, H5T_BIT_MSB, TRUE); + } else { + /* If it's maximal negative number 0x80...000, treat it as if it overflows + * (create a carry) to help conversion. i.e. a character type number 0x80 + * is treated as 0x100. + */ + sfirst = src.prec-1; + is_max_neg = 0; + } +/*fprintf(stderr, "\n after negate int_buf=0x "); +for(i=0; i<buf_size; i++) + fprintf(stderr, "%02x ", int_buf[i]);*/ + + /* Sign bit has been negated if bit vector isn't 0x80...00. Set all bits in front of + * sign bit to 0 in the temporary buffer because they're all negated from the previous + * step. */ + H5T_bit_set(int_buf, src.prec, buf_size*8-src.prec, 0); +/*fprintf(stderr, "\n after bits in front of sign off int_buf=0x "); +for(i=0; i<buf_size; i++) + fprintf(stderr, "%02x ", int_buf[i]);*/ + + /* Set sign bit in destiny */ + H5T_bit_set_d(d, dst.u.f.sign, 1, sign); + } + + first = (size_t)sfirst; +/*fprintf(stderr, "\n first=%d", first);*/ + + + /* + * Calculate the true destination exponent by adjusting according to + * the destination exponent bias. + */ + if (H5T_NORM_NONE==src.u.f.norm) { + expo = first + 1 + dst.u.f.ebias; + } else if (H5T_NORM_IMPLIED==src.u.f.norm) { + expo = first + dst.u.f.ebias; + } else { + assert("normalization method not implemented yet" && 0); + HDabort(); + } + +/*fprintf(stderr, "\n expo=%d,", expo); +fprintf(stderr, "\n expo_max=%d,", expo_max);*/ + + /* Handle mantissa part here */ + if (H5T_NORM_IMPLIED==src.u.f.norm) { + /* Imply first bit */ + H5T_bit_set(int_buf, first, 1, 0); +/*fprintf(stderr, "\n after 1st bit implied int_buf=0x "); +for(i=0; i<buf_size; i++) + fprintf(stderr, "%02x ", int_buf[i]);*/ + } else if (H5T_NORM_NONE==src.u.f.norm) { + first++; + } + + /* Roundup for mantissa */ + if(first > dst.u.f.msize) { + /* If the bit sequence is bigger than the mantissa part, we need to drop off the + * extra bits at the end and do rounding. If we have .50...0(decimal) after radix + * point, we do roundup when the least significant digit before radix is odd, we do + * rounddown if it's even. + */ + + /* Check 1st dropoff bit, see if it's set. */ + if(H5T_bit_get_d(int_buf, (first-dst.u.f.msize-1), 1)) { + /* Check all bits after 1st dropoff bit, see if any of them is set. */ + if((first-dst.u.f.msize-1) > 0 && H5T_bit_get_d(int_buf, 0, (first-dst.u.f.msize-1))) + do_round = 1; + else { /* The .50...0 case */ + /* Check if the least significant bit is odd. */ + if(H5T_bit_get_d(int_buf, (first-dst.u.f.msize), 1)) + do_round = 1; + } + } + + /* Right shift to drop off extra bits */ + H5T_bit_shift(int_buf, (ssize_t)(dst.u.f.msize-first), buf_size); + + if(do_round) { + H5T_bit_inc(int_buf, 0, buf_size*8); + do_round = 0; + + /* If integer is like 0x0ff...fff and we need to round up the + * last f, we get 0x100...000. Treat this special case here. + */ + if(H5T_bit_get_d(int_buf, dst.u.f.msize, 1)) { + if (H5T_NORM_IMPLIED==src.u.f.norm) { + /* The bit at this 1's position was impled already, so this + * number should be 0x200...000. We need to increment the + * exponent in this case. + */ + expo++; + } else if (H5T_NORM_NONE==src.u.f.norm) { + /* Right shift 1 bit to let the carried 1 fit in the mantissa, + * and increment exponent by 1. + */ + H5T_bit_shift(int_buf, -1, buf_size); + expo++; + } + } + } + } else { + /* The bit sequence can fit mantissa part. Left shift to fit in from high-order of + * bit position. */ + H5T_bit_shift(int_buf, (ssize_t)(dst.u.f.msize-first), buf_size); + } + + + /* Check if the exponent is too big */ + expo_max = (hsize_t)HDpow((double)2.0, (double)dst.u.f.esize) - 1; + if(expo > expo_max) + expo = expo_max; + + /* Set exponent in destiny */ + H5T_bit_set_d(d, dst.u.f.epos, dst.u.f.esize, expo); + + /* Copy mantissa into destiny */ + H5T_bit_copy(d, dst.u.f.mpos, int_buf, 0, buf_size*8 > dst.u.f.msize ? dst.u.f.msize : buf_size*8); + + padding: + /* + * Set padding areas in destination. + */ + if (dst.offset>0) { + assert (H5T_PAD_ZERO==dst.lsb_pad || H5T_PAD_ONE==dst.lsb_pad); + H5T_bit_set (d, 0, dst.offset, (hbool_t)(H5T_PAD_ONE==dst.lsb_pad)); + } + if (dst.offset+dst.prec!=8*dst_p->size) { + assert (H5T_PAD_ZERO==dst.msb_pad || H5T_PAD_ONE==dst.msb_pad); + H5T_bit_set (d, dst.offset+dst.prec, + 8*dst_p->size - (dst.offset+ dst.prec), + (hbool_t)(H5T_PAD_ONE==dst.msb_pad)); + } + + /* + * Put the destination in the correct byte order. See note at + * beginning of loop. + */ + if (H5T_ORDER_BE==dst.order) { + half_size = dst_p->size/2; + for (i=0; i<half_size; i++) { + uint8_t tmp = d[dst_p->size-(i+1)]; + d[dst_p->size-(i+1)] = d[i]; + d[i] = tmp; + } + } + + /* + * If we had used a temporary buffer for the destination then we + * should copy the value to the true destination buffer. + */ + if (d==dbuf) + HDmemcpy (dp, d, dst_p->size); + if (buf_stride) { + sp += direction * buf_stride; + dp += direction * buf_stride; + } else { + sp += direction * src_p->size; + dp += direction * dst_p->size; + } + + HDmemset(int_buf, 0, buf_size); + } + + H5MM_xfree(int_buf); + + break; + + default: + HGOTO_ERROR (H5E_DATATYPE, H5E_UNSUPPORTED, FAIL, "unknown conversion command"); + } + +done: + FUNC_LEAVE_NOAPI(ret_value); +} |