/* Decimal floating point support for GDB.
- Copyright 2007 Free Software Foundation, Inc.
+ Copyright 2007-2012 Free Software Foundation, Inc.
This file is part of GDB.
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
+#include "expression.h"
+#include "gdbtypes.h"
+#include "value.h"
+#include "dfp.h"
/* The order of the following headers is important for making sure
decNumber structure is large enough to hold decimal128 digits. */
They are stored in host byte order. This routine does the conversion if
the target byte order is different. */
static void
-match_endianness (const gdb_byte *from, int len, gdb_byte *to)
+match_endianness (const gdb_byte *from, int len, enum bfd_endian byte_order,
+ gdb_byte *to)
{
int i;
#define OPPOSITE_BYTE_ORDER BFD_ENDIAN_BIG
#endif
- if (gdbarch_byte_order (current_gdbarch) == OPPOSITE_BYTE_ORDER)
+ if (byte_order == OPPOSITE_BYTE_ORDER)
for (i = 0; i < len; i++)
to[i] = from[len - i - 1];
else
return;
}
+/* Helper function to get the appropriate libdecnumber context for each size
+ of decimal float. */
+static void
+set_decnumber_context (decContext *ctx, int len)
+{
+ switch (len)
+ {
+ case 4:
+ decContextDefault (ctx, DEC_INIT_DECIMAL32);
+ break;
+ case 8:
+ decContextDefault (ctx, DEC_INIT_DECIMAL64);
+ break;
+ case 16:
+ decContextDefault (ctx, DEC_INIT_DECIMAL128);
+ break;
+ }
+
+ ctx->traps = 0;
+}
+
+/* Check for errors signaled in the decimal context structure. */
+static void
+decimal_check_errors (decContext *ctx)
+{
+ /* An error here could be a division by zero, an overflow, an underflow or
+ an invalid operation (from the DEC_Errors constant in decContext.h).
+ Since GDB doesn't complain about division by zero, overflow or underflow
+ errors for binary floating, we won't complain about them for decimal
+ floating either. */
+ if (ctx->status & DEC_IEEE_854_Invalid_operation)
+ {
+ /* Leave only the error bits in the status flags. */
+ ctx->status &= DEC_IEEE_854_Invalid_operation;
+ error (_("Cannot perform operation: %s"),
+ decContextStatusToString (ctx));
+ }
+}
+
+/* Helper function to convert from libdecnumber's appropriate representation
+ for computation to each size of decimal float. */
+static void
+decimal_from_number (const decNumber *from, gdb_byte *to, int len)
+{
+ decContext set;
+
+ set_decnumber_context (&set, len);
+
+ switch (len)
+ {
+ case 4:
+ decimal32FromNumber ((decimal32 *) to, from, &set);
+ break;
+ case 8:
+ decimal64FromNumber ((decimal64 *) to, from, &set);
+ break;
+ case 16:
+ decimal128FromNumber ((decimal128 *) to, from, &set);
+ break;
+ }
+}
+
+/* Helper function to convert each size of decimal float to libdecnumber's
+ appropriate representation for computation. */
+static void
+decimal_to_number (const gdb_byte *from, int len, decNumber *to)
+{
+ switch (len)
+ {
+ case 4:
+ decimal32ToNumber ((decimal32 *) from, to);
+ break;
+ case 8:
+ decimal64ToNumber ((decimal64 *) from, to);
+ break;
+ case 16:
+ decimal128ToNumber ((decimal128 *) from, to);
+ break;
+ default:
+ error (_("Unknown decimal floating point type."));
+ break;
+ }
+}
+
/* Convert decimal type to its string representation. LEN is the length
of the decimal type, 4 bytes for decimal32, 8 bytes for decimal64 and
16 bytes for decimal128. */
void
-decimal_to_string (const gdb_byte *decbytes, int len, char *s)
+decimal_to_string (const gdb_byte *decbytes, int len,
+ enum bfd_endian byte_order, char *s)
{
gdb_byte dec[16];
- match_endianness (decbytes, len, dec);
+ match_endianness (decbytes, len, byte_order, dec);
+
switch (len)
{
case 4:
decimal128ToString ((decimal128 *) dec, s);
break;
default:
- error (_("Unknown decimal floating point type.\n"));
+ error (_("Unknown decimal floating point type."));
break;
}
}
LEN is the length of the decimal type, 4 bytes for decimal32, 8 bytes for
decimal64 and 16 bytes for decimal128. */
int
-decimal_from_string (gdb_byte *decbytes, int len, const char *string)
+decimal_from_string (gdb_byte *decbytes, int len, enum bfd_endian byte_order,
+ const char *string)
{
decContext set;
gdb_byte dec[16];
+ set_decnumber_context (&set, len);
+
switch (len)
{
case 4:
- decContextDefault (&set, DEC_INIT_DECIMAL32);
- set.traps = 0;
decimal32FromString ((decimal32 *) dec, string, &set);
break;
case 8:
- decContextDefault (&set, DEC_INIT_DECIMAL64);
- set.traps = 0;
decimal64FromString ((decimal64 *) dec, string, &set);
break;
case 16:
- decContextDefault (&set, DEC_INIT_DECIMAL128);
- set.traps = 0;
decimal128FromString ((decimal128 *) dec, string, &set);
break;
default:
- error (_("Unknown decimal floating point type.\n"));
+ error (_("Unknown decimal floating point type."));
break;
}
- match_endianness (dec, len, decbytes);
+ match_endianness (dec, len, byte_order, decbytes);
+
+ /* Check for errors in the DFP operation. */
+ decimal_check_errors (&set);
return 1;
}
+
+/* Converts a value of an integral type to a decimal float of
+ specified LEN bytes. */
+void
+decimal_from_integral (struct value *from,
+ gdb_byte *to, int len, enum bfd_endian byte_order)
+{
+ LONGEST l;
+ gdb_byte dec[16];
+ decNumber number;
+ struct type *type;
+
+ type = check_typedef (value_type (from));
+
+ if (TYPE_LENGTH (type) > 4)
+ /* libdecnumber can convert only 32-bit integers. */
+ error (_("Conversion of large integer to a "
+ "decimal floating type is not supported."));
+
+ l = value_as_long (from);
+
+ if (TYPE_UNSIGNED (type))
+ decNumberFromUInt32 (&number, (unsigned int) l);
+ else
+ decNumberFromInt32 (&number, (int) l);
+
+ decimal_from_number (&number, dec, len);
+ match_endianness (dec, len, byte_order, to);
+}
+
+/* Converts a value of a float type to a decimal float of
+ specified LEN bytes.
+
+ This is an ugly way to do the conversion, but libdecnumber does
+ not offer a direct way to do it. */
+void
+decimal_from_floating (struct value *from,
+ gdb_byte *to, int len, enum bfd_endian byte_order)
+{
+ char *buffer;
+
+ buffer = xstrprintf ("%.30" DOUBLEST_PRINT_FORMAT, value_as_double (from));
+
+ decimal_from_string (to, len, byte_order, buffer);
+
+ xfree (buffer);
+}
+
+/* Converts a decimal float of LEN bytes to a double value. */
+DOUBLEST
+decimal_to_doublest (const gdb_byte *from, int len, enum bfd_endian byte_order)
+{
+ char buffer[MAX_DECIMAL_STRING];
+
+ /* This is an ugly way to do the conversion, but libdecnumber does
+ not offer a direct way to do it. */
+ decimal_to_string (from, len, byte_order, buffer);
+ return strtod (buffer, NULL);
+}
+
+/* Perform operation OP with operands X and Y with sizes LEN_X and LEN_Y
+ and byte orders BYTE_ORDER_X and BYTE_ORDER_Y, and store value in
+ RESULT with size LEN_RESULT and byte order BYTE_ORDER_RESULT. */
+void
+decimal_binop (enum exp_opcode op,
+ const gdb_byte *x, int len_x, enum bfd_endian byte_order_x,
+ const gdb_byte *y, int len_y, enum bfd_endian byte_order_y,
+ gdb_byte *result, int len_result,
+ enum bfd_endian byte_order_result)
+{
+ decContext set;
+ decNumber number1, number2, number3;
+ gdb_byte dec1[16], dec2[16], dec3[16];
+
+ match_endianness (x, len_x, byte_order_x, dec1);
+ match_endianness (y, len_y, byte_order_y, dec2);
+
+ decimal_to_number (dec1, len_x, &number1);
+ decimal_to_number (dec2, len_y, &number2);
+
+ set_decnumber_context (&set, len_result);
+
+ switch (op)
+ {
+ case BINOP_ADD:
+ decNumberAdd (&number3, &number1, &number2, &set);
+ break;
+ case BINOP_SUB:
+ decNumberSubtract (&number3, &number1, &number2, &set);
+ break;
+ case BINOP_MUL:
+ decNumberMultiply (&number3, &number1, &number2, &set);
+ break;
+ case BINOP_DIV:
+ decNumberDivide (&number3, &number1, &number2, &set);
+ break;
+ case BINOP_EXP:
+ decNumberPower (&number3, &number1, &number2, &set);
+ break;
+ default:
+ internal_error (__FILE__, __LINE__,
+ _("Unknown decimal floating point operation."));
+ break;
+ }
+
+ /* Check for errors in the DFP operation. */
+ decimal_check_errors (&set);
+
+ decimal_from_number (&number3, dec3, len_result);
+
+ match_endianness (dec3, len_result, byte_order_result, result);
+}
+
+/* Returns true if X (which is LEN bytes wide) is the number zero. */
+int
+decimal_is_zero (const gdb_byte *x, int len, enum bfd_endian byte_order)
+{
+ decNumber number;
+ gdb_byte dec[16];
+
+ match_endianness (x, len, byte_order, dec);
+ decimal_to_number (dec, len, &number);
+
+ return decNumberIsZero (&number);
+}
+
+/* Compares two numbers numerically. If X is less than Y then the return value
+ will be -1. If they are equal, then the return value will be 0. If X is
+ greater than the Y then the return value will be 1. */
+int
+decimal_compare (const gdb_byte *x, int len_x, enum bfd_endian byte_order_x,
+ const gdb_byte *y, int len_y, enum bfd_endian byte_order_y)
+{
+ decNumber number1, number2, result;
+ decContext set;
+ gdb_byte dec1[16], dec2[16];
+ int len_result;
+
+ match_endianness (x, len_x, byte_order_x, dec1);
+ match_endianness (y, len_y, byte_order_y, dec2);
+
+ decimal_to_number (dec1, len_x, &number1);
+ decimal_to_number (dec2, len_y, &number2);
+
+ /* Perform the comparison in the larger of the two sizes. */
+ len_result = len_x > len_y ? len_x : len_y;
+ set_decnumber_context (&set, len_result);
+
+ decNumberCompare (&result, &number1, &number2, &set);
+
+ /* Check for errors in the DFP operation. */
+ decimal_check_errors (&set);
+
+ if (decNumberIsNaN (&result))
+ error (_("Comparison with an invalid number (NaN)."));
+ else if (decNumberIsZero (&result))
+ return 0;
+ else if (decNumberIsNegative (&result))
+ return -1;
+ else
+ return 1;
+}
+
+/* Convert a decimal value from a decimal type with LEN_FROM bytes to a
+ decimal type with LEN_TO bytes. */
+void
+decimal_convert (const gdb_byte *from, int len_from,
+ enum bfd_endian byte_order_from, gdb_byte *to, int len_to,
+ enum bfd_endian byte_order_to)
+{
+ decNumber number;
+ gdb_byte dec[16];
+
+ match_endianness (from, len_from, byte_order_from, dec);
+
+ decimal_to_number (dec, len_from, &number);
+ decimal_from_number (&number, dec, len_to);
+
+ match_endianness (dec, len_to, byte_order_to, to);
+}
projects / deliverable / binutils-gdb.git / blobdiff