diff options
Diffstat (limited to 'gdb/utils.c')
-rw-r--r-- | gdb/utils.c | 315 |
1 files changed, 312 insertions, 3 deletions
diff --git a/gdb/utils.c b/gdb/utils.c index 97b6a9b..22e511c 100644 --- a/gdb/utils.c +++ b/gdb/utils.c @@ -18,7 +18,7 @@ along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include "defs.h" -#if !defined(__GO32__) && !defined(__WIN32__) +#if !defined(__GO32__) && !defined(__WIN32__) && !defined(MPW) #include <sys/ioctl.h> #include <sys/param.h> #include <pwd.h> @@ -603,9 +603,9 @@ request_quit (signo) signal (signo, request_quit); /* start-sanitize-gm */ -#ifdef GENERAL_MAGIC_HACKS +#ifdef GENERAL_MAGIC target_kill (); -#endif /* GENERAL_MAGIC_HACKS */ +#endif /* GENERAL_MAGIC */ /* end-sanitize-gm */ #ifdef REQUEST_QUIT @@ -1950,4 +1950,313 @@ initialize_utils () #ifdef SIGWINCH_HANDLER_BODY SIGWINCH_HANDLER_BODY #endif + +#ifdef HAVE_LONG_DOUBLE +/* Support for converting target fp numbers into host long double format. */ + +/* XXX - This code should really be in libiberty/floatformat.c, however + configuration issues with libiberty made this very difficult to do in the + available time. */ + +#include "floatformat.h" +#include <math.h> /* ldexp */ + +/* The odds that CHAR_BIT will be anything but 8 are low enough that I'm not + going to bother with trying to muck around with whether it is defined in + a system header, what we do if not, etc. */ +#define FLOATFORMAT_CHAR_BIT 8 + +static unsigned long get_field PARAMS ((unsigned char *, + enum floatformat_byteorders, + unsigned int, + unsigned int, + unsigned int)); + +/* Extract a field which starts at START and is LEN bytes long. DATA and + TOTAL_LEN are the thing we are extracting it from, in byteorder ORDER. */ +static unsigned long +get_field (data, order, total_len, start, len) + unsigned char *data; + enum floatformat_byteorders order; + unsigned int total_len; + unsigned int start; + unsigned int len; +{ + unsigned long result; + unsigned int cur_byte; + int cur_bitshift; + + /* Start at the least significant part of the field. */ + cur_byte = (start + len) / FLOATFORMAT_CHAR_BIT; + if (order == floatformat_little) + cur_byte = (total_len / FLOATFORMAT_CHAR_BIT) - cur_byte - 1; + cur_bitshift = + ((start + len) % FLOATFORMAT_CHAR_BIT) - FLOATFORMAT_CHAR_BIT; + result = *(data + cur_byte) >> (-cur_bitshift); + cur_bitshift += FLOATFORMAT_CHAR_BIT; + if (order == floatformat_little) + ++cur_byte; + else + --cur_byte; + + /* Move towards the most significant part of the field. */ + while (cur_bitshift < len) + { + if (len - cur_bitshift < FLOATFORMAT_CHAR_BIT) + /* This is the last byte; zero out the bits which are not part of + this field. */ + result |= + (*(data + cur_byte) & ((1 << (len - cur_bitshift)) - 1)) + << cur_bitshift; + else + result |= *(data + cur_byte) << cur_bitshift; + cur_bitshift += FLOATFORMAT_CHAR_BIT; + if (order == floatformat_little) + ++cur_byte; + else + --cur_byte; + } + return result; +} + +/* Convert from FMT to a long double. + FROM is the address of the extended float. + Store the long double in *TO. */ + +void +floatformat_to_long_double (fmt, from, to) + const struct floatformat *fmt; + char *from; + long double *to; +{ + unsigned char *ufrom = (unsigned char *)from; + long double dto; + long exponent; + unsigned long mant; + unsigned int mant_bits, mant_off; + int mant_bits_left; + + exponent = get_field (ufrom, fmt->byteorder, fmt->totalsize, + fmt->exp_start, fmt->exp_len); + /* Note that if exponent indicates a NaN, we can't really do anything useful + (not knowing if the host has NaN's, or how to build one). So it will + end up as an infinity or something close; that is OK. */ + + mant_bits_left = fmt->man_len; + mant_off = fmt->man_start; + dto = 0.0; + exponent -= fmt->exp_bias; + + /* Build the result algebraically. Might go infinite, underflow, etc; + who cares. */ + +/* If this format uses a hidden bit, explicitly add it in now. Otherwise, + increment the exponent by one to account for the integer bit. */ + + if (fmt->intbit == floatformat_intbit_no) + dto = ldexp (1.0, exponent); + else + exponent++; + + while (mant_bits_left > 0) + { + mant_bits = min (mant_bits_left, 32); + + mant = get_field (ufrom, fmt->byteorder, fmt->totalsize, + mant_off, mant_bits); + + dto += ldexp ((double)mant, exponent - mant_bits); + exponent -= mant_bits; + mant_off += mant_bits; + mant_bits_left -= mant_bits; + } + + /* Negate it if negative. */ + if (get_field (ufrom, fmt->byteorder, fmt->totalsize, fmt->sign_start, 1)) + dto = -dto; + memcpy (to, &dto, sizeof (dto)); +} + +static void put_field PARAMS ((unsigned char *, enum floatformat_byteorders, + unsigned int, + unsigned int, + unsigned int, + unsigned long)); + +/* Set a field which starts at START and is LEN bytes long. DATA and + TOTAL_LEN are the thing we are extracting it from, in byteorder ORDER. */ +static void +put_field (data, order, total_len, start, len, stuff_to_put) + unsigned char *data; + enum floatformat_byteorders order; + unsigned int total_len; + unsigned int start; + unsigned int len; + unsigned long stuff_to_put; +{ + unsigned int cur_byte; + int cur_bitshift; + + /* Start at the least significant part of the field. */ + cur_byte = (start + len) / FLOATFORMAT_CHAR_BIT; + if (order == floatformat_little) + cur_byte = (total_len / FLOATFORMAT_CHAR_BIT) - cur_byte - 1; + cur_bitshift = + ((start + len) % FLOATFORMAT_CHAR_BIT) - FLOATFORMAT_CHAR_BIT; + *(data + cur_byte) &= + ~(((1 << ((start + len) % FLOATFORMAT_CHAR_BIT)) - 1) << (-cur_bitshift)); + *(data + cur_byte) |= + (stuff_to_put & ((1 << FLOATFORMAT_CHAR_BIT) - 1)) << (-cur_bitshift); + cur_bitshift += FLOATFORMAT_CHAR_BIT; + if (order == floatformat_little) + ++cur_byte; + else + --cur_byte; + + /* Move towards the most significant part of the field. */ + while (cur_bitshift < len) + { + if (len - cur_bitshift < FLOATFORMAT_CHAR_BIT) + { + /* This is the last byte. */ + *(data + cur_byte) &= + ~((1 << (len - cur_bitshift)) - 1); + *(data + cur_byte) |= (stuff_to_put >> cur_bitshift); + } + else + *(data + cur_byte) = ((stuff_to_put >> cur_bitshift) + & ((1 << FLOATFORMAT_CHAR_BIT) - 1)); + cur_bitshift += FLOATFORMAT_CHAR_BIT; + if (order == floatformat_little) + ++cur_byte; + else + --cur_byte; + } +} + +/* Return the fractional part of VALUE, and put the exponent of VALUE in *EPTR. + The range of the returned value is >= 0.5 and < 1.0. This is equivalent to + frexp, but operates on the long double data type. */ + +static long double ldfrexp PARAMS ((long double value, int *eptr)); + +static long double +ldfrexp (value, eptr) + long double value; + int *eptr; +{ + long double tmp; + int exp; + + /* Unfortunately, there are no portable functions for extracting the exponent + of a long double, so we have to do it iteratively by multiplying or dividing + by two until the fraction is between 0.5 and 1.0. */ + + if (value < 0.0l) + value = -value; + + tmp = 1.0l; + exp = 0; + + if (value >= tmp) /* Value >= 1.0 */ + while (value >= tmp) + { + tmp *= 2.0l; + exp++; + } + else if (value != 0.0l) /* Value < 1.0 and > 0.0 */ + { + while (value < tmp) + { + tmp /= 2.0l; + exp--; + } + tmp *= 2.0l; + exp++; + } + + *eptr = exp; + return value/tmp; +} + +/* The converse: convert the long double *FROM to an extended float + and store where TO points. Neither FROM nor TO have any alignment + restrictions. */ + +void +floatformat_from_long_double (fmt, from, to) + CONST struct floatformat *fmt; + long double *from; + char *to; +{ + long double dfrom; + int exponent; + long double mant; + unsigned int mant_bits, mant_off; + int mant_bits_left; + unsigned char *uto = (unsigned char *)to; + + memcpy (&dfrom, from, sizeof (dfrom)); + memset (uto, 0, fmt->totalsize / FLOATFORMAT_CHAR_BIT); + if (dfrom == 0) + return; /* Result is zero */ + if (dfrom != dfrom) + { + /* From is NaN */ + put_field (uto, fmt->byteorder, fmt->totalsize, fmt->exp_start, + fmt->exp_len, fmt->exp_nan); + /* Be sure it's not infinity, but NaN value is irrel */ + put_field (uto, fmt->byteorder, fmt->totalsize, fmt->man_start, + 32, 1); + return; + } + + /* If negative, set the sign bit. */ + if (dfrom < 0) + { + put_field (uto, fmt->byteorder, fmt->totalsize, fmt->sign_start, 1, 1); + dfrom = -dfrom; + } + + /* How to tell an infinity from an ordinary number? FIXME-someday */ + + mant = ldfrexp (dfrom, &exponent); + put_field (uto, fmt->byteorder, fmt->totalsize, fmt->exp_start, fmt->exp_len, + exponent + fmt->exp_bias - 1); + + mant_bits_left = fmt->man_len; + mant_off = fmt->man_start; + while (mant_bits_left > 0) + { + unsigned long mant_long; + mant_bits = mant_bits_left < 32 ? mant_bits_left : 32; + + mant *= 4294967296.0; + mant_long = (unsigned long)mant; + mant -= mant_long; + + /* If the integer bit is implicit, then we need to discard it. + If we are discarding a zero, we should be (but are not) creating + a denormalized number which means adjusting the exponent + (I think). */ + if (mant_bits_left == fmt->man_len + && fmt->intbit == floatformat_intbit_no) + { + mant_long &= 0x7fffffff; + mant_bits -= 1; + } + else if (mant_bits < 32) + { + /* The bits we want are in the most significant MANT_BITS bits of + mant_long. Move them to the least significant. */ + mant_long >>= 32 - mant_bits; + } + + put_field (uto, fmt->byteorder, fmt->totalsize, + mant_off, mant_bits, mant_long); + mant_off += mant_bits; + mant_bits_left -= mant_bits; + } +} +#endif /* HAVE_LONG_DOUBLE */ |