diff options
Diffstat (limited to 'libiberty/floatformat.c')
| -rw-r--r-- | libiberty/floatformat.c | 49 |
1 files changed, 41 insertions, 8 deletions
diff --git a/libiberty/floatformat.c b/libiberty/floatformat.c index d69024f7390..ee87e273415 100644 --- a/libiberty/floatformat.c +++ b/libiberty/floatformat.c @@ -1,5 +1,5 @@ /* IEEE floating point support routines, for GDB, the GNU Debugger. - Copyright (C) 1991, 1994, 1999, 2000 Free Software Foundation, Inc. + Copyright (C) 1991, 1994, 1999, 2000, 2003 Free Software Foundation, Inc. This file is part of GDB. @@ -143,17 +143,17 @@ const struct floatformat floatformat_ia64_quad_little = "floatformat_ia64_quad_little" }; -static unsigned long get_field PARAMS ((unsigned char *, +static unsigned long get_field PARAMS ((const 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 +/* Extract a field which starts at START and is LEN bits 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; + const unsigned char *data; enum floatformat_byteorders order; unsigned int total_len; unsigned int start; @@ -207,10 +207,10 @@ get_field (data, order, total_len, start, len) void floatformat_to_double (fmt, from, to) const struct floatformat *fmt; - char *from; + const char *from; double *to; { - unsigned char *ufrom = (unsigned char *)from; + const unsigned char *ufrom = (const unsigned char *)from; double dto; long exponent; unsigned long mant; @@ -273,7 +273,7 @@ static void put_field PARAMS ((unsigned char *, enum floatformat_byteorders, unsigned int, unsigned long)); -/* Set a field which starts at START and is LEN bytes long. DATA and +/* Set a field which starts at START and is LEN bits 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) @@ -331,7 +331,7 @@ put_field (data, order, total_len, start, len, stuff_to_put) void floatformat_from_double (fmt, from, to) const struct floatformat *fmt; - double *from; + const double *from; char *to; { double dfrom; @@ -404,6 +404,39 @@ floatformat_from_double (fmt, from, to) } } +/* Return non-zero iff the data at FROM is a valid number in format FMT. */ + +int +floatformat_is_valid (fmt, from) + const struct floatformat *fmt; + const char *from; +{ + if (fmt == &floatformat_i387_ext) + { + /* In the i387 double-extended format, if the exponent is all + ones, then the integer bit must be set. If the exponent + is neither 0 nor ~0, the intbit must also be set. Only + if the exponent is zero can it be zero, and then it must + be zero. */ + unsigned long exponent, int_bit; + const unsigned char *ufrom = (const unsigned char *) from; + + exponent = get_field (ufrom, fmt->byteorder, fmt->totalsize, + fmt->exp_start, fmt->exp_len); + int_bit = get_field (ufrom, fmt->byteorder, fmt->totalsize, + fmt->man_start, 1); + + if ((exponent == 0) != (int_bit == 0)) + return 0; + else + return 1; + } + + /* Other formats with invalid representations should be added + here. */ + return 1; +} + #ifdef IEEE_DEBUG |