/* expr.c -operands, expressions-
- Copyright (C) 1987, 90, 91, 92, 93, 94, 95, 96, 1997
+ Copyright (C) 1987, 90, 91, 92, 93, 94, 95, 96, 1997, 1998
Free Software Foundation, Inc.
This file is part of GAS, the GNU Assembler.
#include <ctype.h>
#include <string.h>
+#define min(a, b) ((a) < (b) ? (a) : (b))
#include "as.h"
#include "obstack.h"
return 0;
}
\f
+/* Utilities for building expressions.
+ Since complex expressions are recorded as symbols for use in other
+ expressions these return a symbolS * and not an expressionS *.
+ These explicitly do not take an "add_number" argument. */
+/* ??? For completeness' sake one might want expr_build_symbol.
+ It would just return its argument. */
+
+/* Build an expression for an unsigned constant.
+ The corresponding one for signed constants is missing because
+ there's currently no need for it. One could add an unsigned_p flag
+ but that seems more clumsy. */
+
+symbolS *
+expr_build_uconstant (value)
+ offsetT value;
+{
+ expressionS e;
+
+ e.X_op = O_constant;
+ e.X_add_number = value;
+ e.X_unsigned = 1;
+ return make_expr_symbol (&e);
+}
+
+/* Build an expression for OP s1. */
+
+symbolS *
+expr_build_unary (op, s1)
+ operatorT op;
+ symbolS *s1;
+{
+ expressionS e;
+
+ e.X_op = op;
+ e.X_add_symbol = s1;
+ e.X_add_number = 0;
+ return make_expr_symbol (&e);
+}
+
+/* Build an expression for s1 OP s2. */
+
+symbolS *
+expr_build_binary (op, s1, s2)
+ operatorT op;
+ symbolS *s1;
+ symbolS *s2;
+{
+ expressionS e;
+
+ e.X_op = op;
+ e.X_add_symbol = s1;
+ e.X_op_symbol = s2;
+ e.X_add_number = 0;
+ return make_expr_symbol (&e);
+}
+\f
/*
* Build any floating-point literal here.
* Also build any bignum literal here.
expressionP->X_add_number = -1;
}
+static valueT
+generic_bignum_to_int32 ()
+{
+ valueT number =
+ ((generic_bignum[1] & LITTLENUM_MASK) << LITTLENUM_NUMBER_OF_BITS)
+ | (generic_bignum[0] & LITTLENUM_MASK);
+ number &= 0xffffffff;
+ return number;
+}
+
+#ifdef BFD64
+static valueT
+generic_bignum_to_int64 ()
+{
+ valueT number =
+ ((((((((valueT) generic_bignum[3] & LITTLENUM_MASK)
+ << LITTLENUM_NUMBER_OF_BITS)
+ | ((valueT) generic_bignum[2] & LITTLENUM_MASK))
+ << LITTLENUM_NUMBER_OF_BITS)
+ | ((valueT) generic_bignum[1] & LITTLENUM_MASK))
+ << LITTLENUM_NUMBER_OF_BITS)
+ | ((valueT) generic_bignum[0] & LITTLENUM_MASK));
+ return number;
+}
+#endif
+
static void
integer_constant (radix, expressionP)
int radix;
/* c contains character after number. */
/* input_line_pointer->char after c. */
small = (input_line_pointer - start - 1) < too_many_digits;
- if (!small)
+
+ if (radix == 16 && c == '_')
+ {
+ /* This is literal of the form 0x333_0_12345678_1.
+ This example is equivalent to 0x00000333000000001234567800000001. */
+
+ int num_little_digits = 0;
+ int i;
+ input_line_pointer = start; /*->1st digit. */
+
+ know (LITTLENUM_NUMBER_OF_BITS == 16);
+
+ for (c = '_'; c == '_'; num_little_digits+=2)
+ {
+
+ /* Convert one 64-bit word. */
+ int ndigit = 0;
+ number = 0;
+ for (c = *input_line_pointer++;
+ (digit = hex_value (c)) < maxdig;
+ c = *(input_line_pointer++))
+ {
+ number = number * radix + digit;
+ ndigit++;
+ }
+
+ /* Check for 8 digit per word max. */
+ if (ndigit > 8)
+ as_bad ("An bignum with underscores may not have more than 8 hex digits in any word.");
+
+ /* Add this chunk to the bignum. Shift things down 2 little digits.*/
+ know (LITTLENUM_NUMBER_OF_BITS == 16);
+ for (i = min (num_little_digits + 1, SIZE_OF_LARGE_NUMBER - 1); i >= 2; i--)
+ generic_bignum[i] = generic_bignum[i-2];
+
+ /* Add the new digits as the least significant new ones. */
+ generic_bignum[0] = number & 0xffffffff;
+ generic_bignum[1] = number >> 16;
+ }
+
+ /* Again, c is char after number, input_line_pointer->after c. */
+
+ if (num_little_digits > SIZE_OF_LARGE_NUMBER - 1)
+ num_little_digits = SIZE_OF_LARGE_NUMBER - 1;
+
+ assert (num_little_digits >= 4);
+
+ if (num_little_digits != 8)
+ as_bad ("A bignum with underscores must have exactly 4 words.");
+
+ /* We might have some leading zeros. These can be trimmed to give
+ * us a change to fit this constant into a small number.
+ */
+ while (generic_bignum[num_little_digits-1] == 0 && num_little_digits > 1)
+ num_little_digits--;
+
+ if (num_little_digits <= 2)
+ {
+ /* will fit into 32 bits. */
+ number = generic_bignum_to_int32 ();
+ small = 1;
+ }
+#ifdef BFD64
+ else if (num_little_digits <= 4)
+ {
+ /* Will fit into 64 bits. */
+ number = generic_bignum_to_int64 ();
+ small = 1;
+ }
+#endif
+ else
+ {
+ small = 0;
+ number = num_little_digits; /* number of littlenums in the bignum. */
+ }
+ }
+ else if (!small)
{
/*
* we saw a lot of digits. manufacture a bignum the hard way.
if (leader < generic_bignum + 2)
{
/* will fit into 32 bits. */
- number =
- ((generic_bignum[1] & LITTLENUM_MASK) << LITTLENUM_NUMBER_OF_BITS)
- | (generic_bignum[0] & LITTLENUM_MASK);
- number &= 0xffffffff
+ number = generic_bignum_to_int32 ();
small = 1;
}
#ifdef BFD64
else if (leader < generic_bignum + 4)
{
/* Will fit into 64 bits. */
- number =
- ((((((((valueT) generic_bignum[3] & LITTLENUM_MASK)
- << LITTLENUM_NUMBER_OF_BITS)
- | ((valueT) generic_bignum[2] & LITTLENUM_MASK))
- << LITTLENUM_NUMBER_OF_BITS)
- | ((valueT) generic_bignum[1] & LITTLENUM_MASK))
- << LITTLENUM_NUMBER_OF_BITS)
- | ((valueT) generic_bignum[0] & LITTLENUM_MASK));
+ number = generic_bignum_to_int64 ();
small = 1;
}
#endif
}
/*NOTREACHED*/
-}
+}
/* Parse an expression. */
projects / binutils-gdb.git / commitdiff