/* expr.c -operands, expressions-
Copyright 1987, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2002
- Free Software Foundation, Inc.
+ 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2009, 2010, 2011,
+ 2012 Free Software Foundation, Inc.
This file is part of GAS, the GNU Assembler.
GAS is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2, or (at your option)
+ the Free Software Foundation; either version 3, or (at your option)
any later version.
GAS is distributed in the hope that it will be useful,
You should have received a copy of the GNU General Public License
along with GAS; see the file COPYING. If not, write to the Free
- Software Foundation, 59 Temple Place - Suite 330, Boston, MA
- 02111-1307, USA. */
+ Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
+ 02110-1301, USA. */
/* This is really a branch office of as-read.c. I split it out to clearly
distinguish the world of expressions from the world of statements.
(It also gives smaller files to re-compile.)
Here, "operand"s are of expressions, not instructions. */
-#include <string.h>
#define min(a, b) ((a) < (b) ? (a) : (b))
#include "as.h"
#include "safe-ctype.h"
#include "obstack.h"
+#ifdef HAVE_LIMITS_H
+#include <limits.h>
+#endif
+#ifndef CHAR_BIT
+#define CHAR_BIT 8
+#endif
+
static void floating_constant (expressionS * expressionP);
static valueT generic_bignum_to_int32 (void);
#ifdef BFD64
#endif
static void integer_constant (int radix, expressionS * expressionP);
static void mri_char_constant (expressionS *);
-static void current_location (expressionS *);
static void clean_up_expression (expressionS * expressionP);
-static segT operand (expressionS *);
-static operatorT operator (int *);
+static segT operand (expressionS *, enum expr_mode);
+static operatorT operatorf (int *);
extern const char EXP_CHARS[], FLT_CHARS[];
zero.X_op = O_constant;
zero.X_add_number = 0;
zero.X_unsigned = 0;
+ zero.X_extrabit = 0;
clean_up_expression (&zero);
expressionP = &zero;
}
symbolP = symbol_create (FAKE_LABEL_NAME,
(expressionP->X_op == O_constant
? absolute_section
- : expr_section),
+ : expressionP->X_op == O_register
+ ? reg_section
+ : expr_section),
0, &zero_address_frag);
symbol_set_value_expression (symbolP, expressionP);
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 (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 (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;
+ e.X_extrabit = 0;
return make_expr_symbol (&e);
}
expressionS e;
current_location (&e);
- return make_expr_symbol (&e);
+ return symbol_clone_if_forward_ref (make_expr_symbol (&e));
}
\f
/* Build any floating-point literal here.
0 /* sign. */
};
-/* If nonzero, we've been asked to assemble nan, +inf or -inf. */
-int generic_floating_point_magic;
\f
static void
floating_constant (expressionS *expressionP)
{
c = *--suffix;
c = TOUPPER (c);
- if (c == 'B')
+ /* If we have both NUMBERS_WITH_SUFFIX and LOCAL_LABELS_FB,
+ we distinguish between 'B' and 'b'. This is the case for
+ Z80. */
+ if ((NUMBERS_WITH_SUFFIX && LOCAL_LABELS_FB ? *suffix : c) == 'B')
radix = 2;
else if (c == 'D')
radix = 10;
if (num_little_digits > SIZE_OF_LARGE_NUMBER - 1)
num_little_digits = SIZE_OF_LARGE_NUMBER - 1;
- assert (num_little_digits >= 4);
+ gas_assert (num_little_digits >= 4);
if (num_little_digits != 8)
as_bad (_("a bignum with underscores must have exactly 4 words"));
else
{
expressionP->X_op = O_constant;
-#ifdef TARGET_WORD_SIZE
- /* Sign extend NUMBER. */
- number |= (-(number >> (TARGET_WORD_SIZE - 1))) << (TARGET_WORD_SIZE - 1);
-#endif
expressionP->X_add_number = number;
input_line_pointer--; /* Restore following character. */
} /* Really just a number. */
/* Return an expression representing the current location. This
handles the magic symbol `.'. */
-static void
+void
current_location (expressionS *expressionp)
{
if (now_seg == absolute_section)
else
{
expressionp->X_op = O_symbol;
- expressionp->X_add_symbol = symbol_temp_new_now ();
+ expressionp->X_add_symbol = &dot_symbol;
expressionp->X_add_number = 0;
}
}
Input_line_pointer->(next non-blank) char after operand. */
static segT
-operand (expressionS *expressionP)
+operand (expressionS *expressionP, enum expr_mode mode)
{
char c;
symbolS *symbolP; /* Points to symbol. */
something like ``.quad 0x80000000'' is not sign extended even
though it appears negative if valueT is 32 bits. */
expressionP->X_unsigned = 1;
+ expressionP->X_extrabit = 0;
/* Digits, assume it is a bignum. */
break;
- case '(':
#ifndef NEED_INDEX_OPERATOR
case '[':
+# ifdef md_need_index_operator
+ if (md_need_index_operator())
+ goto de_fault;
+# endif
+ /* FALLTHROUGH */
#endif
+ case '(':
/* Didn't begin with digit & not a name. */
- segment = expression (expressionP);
+ segment = expr (0, expressionP, mode);
/* expression () will pass trailing whitespace. */
if ((c == '(' && *input_line_pointer != ')')
|| (c == '[' && *input_line_pointer != ']'))
- {
-#ifdef RELAX_PAREN_GROUPING
- if (c != '(')
-#endif
- as_bad (_("missing '%c'"), c == '(' ? ')' : ']');
- }
+ as_bad (_("missing '%c'"), c == '(' ? ')' : ']');
else
input_line_pointer++;
SKIP_WHITESPACE ();
mri_char_constant (expressionP);
break;
- case '+':
- (void) operand (expressionP);
- break;
-
#ifdef TC_M68K
case '"':
/* Double quote is the bitwise not operator in MRI mode. */
goto isname;
case '!':
case '-':
+ case '+':
{
- operand (expressionP);
+#ifdef md_operator
+ unary:
+#endif
+ operand (expressionP, mode);
if (expressionP->X_op == O_constant)
{
/* input_line_pointer -> char after operand. */
This is compatible with other people's
assemblers. Sigh. */
expressionP->X_unsigned = 0;
+ if (expressionP->X_add_number)
+ expressionP->X_extrabit ^= 1;
}
else if (c == '~' || c == '"')
expressionP->X_add_number = ~ expressionP->X_add_number;
- else
+ else if (c == '!')
expressionP->X_add_number = ! expressionP->X_add_number;
}
else if (expressionP->X_op == O_big
else
generic_floating_point_number.sign = 'N';
}
+ else if (expressionP->X_op == O_big
+ && expressionP->X_add_number > 0)
+ {
+ int i;
+
+ if (c == '~' || c == '-')
+ {
+ for (i = 0; i < expressionP->X_add_number; ++i)
+ generic_bignum[i] = ~generic_bignum[i];
+
+ /* Extend the bignum to at least the size of .octa. */
+ if (expressionP->X_add_number < SIZE_OF_LARGE_NUMBER)
+ {
+ expressionP->X_add_number = SIZE_OF_LARGE_NUMBER;
+ for (; i < expressionP->X_add_number; ++i)
+ generic_bignum[i] = ~(LITTLENUM_TYPE) 0;
+ }
+
+ if (c == '-')
+ for (i = 0; i < expressionP->X_add_number; ++i)
+ {
+ generic_bignum[i] += 1;
+ if (generic_bignum[i])
+ break;
+ }
+ }
+ else if (c == '!')
+ {
+ for (i = 0; i < expressionP->X_add_number; ++i)
+ if (generic_bignum[i] != 0)
+ break;
+ expressionP->X_add_number = i >= expressionP->X_add_number;
+ expressionP->X_op = O_constant;
+ expressionP->X_unsigned = 1;
+ expressionP->X_extrabit = 0;
+ }
+ }
else if (expressionP->X_op != O_illegal
&& expressionP->X_op != O_absent)
{
- expressionP->X_add_symbol = make_expr_symbol (expressionP);
- if (c == '-')
- expressionP->X_op = O_uminus;
- else if (c == '~' || c == '"')
- expressionP->X_op = O_bit_not;
- else
- expressionP->X_op = O_logical_not;
- expressionP->X_add_number = 0;
+ if (c != '+')
+ {
+ expressionP->X_add_symbol = make_expr_symbol (expressionP);
+ if (c == '-')
+ expressionP->X_op = O_uminus;
+ else if (c == '~' || c == '"')
+ expressionP->X_op = O_bit_not;
+ else
+ expressionP->X_op = O_logical_not;
+ expressionP->X_add_number = 0;
+ }
}
else
as_warn (_("Unary operator %c ignored because bad operand follows"),
if (! flag_m68k_mri)
goto de_fault;
#endif
- if (flag_m68k_mri && hex_p (*input_line_pointer))
+ if (DOLLAR_AMBIGU && hex_p (*input_line_pointer))
{
- /* In MRI mode, '$' is also used as the prefix for a
- hexadecimal constant. */
+ /* In MRI mode and on Z80, '$' is also used as the prefix
+ for a hexadecimal constant. */
integer_constant (16, expressionP);
break;
}
#endif
default:
-#ifdef TC_M68K
+#if defined(md_need_index_operator) || defined(TC_M68K)
de_fault:
#endif
if (is_name_beginner (c)) /* Here if did not begin with a digit. */
name = --input_line_pointer;
c = get_symbol_end ();
+#ifdef md_operator
+ {
+ operatorT op = md_operator (name, 1, &c);
+
+ switch (op)
+ {
+ case O_uminus:
+ *input_line_pointer = c;
+ c = '-';
+ goto unary;
+ case O_bit_not:
+ *input_line_pointer = c;
+ c = '~';
+ goto unary;
+ case O_logical_not:
+ *input_line_pointer = c;
+ c = '!';
+ goto unary;
+ case O_illegal:
+ as_bad (_("invalid use of operator \"%s\""), name);
+ break;
+ default:
+ break;
+ }
+ if (op != O_absent && op != O_illegal)
+ {
+ *input_line_pointer = c;
+ expr (9, expressionP, mode);
+ expressionP->X_add_symbol = make_expr_symbol (expressionP);
+ expressionP->X_op_symbol = NULL;
+ expressionP->X_add_number = 0;
+ expressionP->X_op = op;
+ break;
+ }
+ }
+#endif
+
#ifdef md_parse_name
/* This is a hook for the backend to parse certain names
specially in certain contexts. If a name always has a
specific value, it can often be handled by simply
entering it in the symbol table. */
- if (md_parse_name (name, expressionP, &c))
+ if (md_parse_name (name, expressionP, mode, &c))
{
*input_line_pointer = c;
break;
/* If we have an absolute symbol or a reg, then we know its
value now. */
segment = S_GET_SEGMENT (symbolP);
- if (segment == absolute_section)
+ if (mode != expr_defer
+ && segment == absolute_section
+ && !S_FORCE_RELOC (symbolP, 0))
{
expressionP->X_op = O_constant;
expressionP->X_add_number = S_GET_VALUE (symbolP);
}
- else if (segment == reg_section)
+ else if (mode != expr_defer && segment == reg_section)
{
expressionP->X_op = O_register;
expressionP->X_add_number = S_GET_VALUE (symbolP);
if (expressionP->X_add_symbol)
symbol_mark_used (expressionP->X_add_symbol);
+ if (mode != expr_defer)
+ {
+ expressionP->X_add_symbol
+ = symbol_clone_if_forward_ref (expressionP->X_add_symbol);
+ expressionP->X_op_symbol
+ = symbol_clone_if_forward_ref (expressionP->X_op_symbol);
+ }
+
switch (expressionP->X_op)
{
default:
#undef __
#define __ O_illegal
+#ifndef O_SINGLE_EQ
+#define O_SINGLE_EQ O_illegal
+#endif
/* Maps ASCII -> operators. */
static const operatorT op_encoding[256] = {
__, O_bit_or_not, __, __, __, O_modulus, O_bit_and, __,
__, __, O_multiply, O_add, __, O_subtract, __, O_divide,
__, __, __, __, __, __, __, __,
- __, __, __, __, O_lt, __, O_gt, __,
+ __, __, __, __, O_lt, O_SINGLE_EQ, O_gt, __,
__, __, __, __, __, __, __, __,
__, __, __, __, __, __, __, __,
__, __, __, __, __, __, __, __,
7 * / % << >>
8 unary - unary ~
*/
-static operator_rankT op_rank[] = {
+static operator_rankT op_rank[O_max] = {
0, /* O_illegal */
0, /* O_absent */
0, /* O_constant */
3, /* O_logical_and */
2, /* O_logical_or */
1, /* O_index */
- 0, /* O_md1 */
- 0, /* O_md2 */
- 0, /* O_md3 */
- 0, /* O_md4 */
- 0, /* O_md5 */
- 0, /* O_md6 */
- 0, /* O_md7 */
- 0, /* O_md8 */
- 0, /* O_md9 */
- 0, /* O_md10 */
- 0, /* O_md11 */
- 0, /* O_md12 */
- 0, /* O_md13 */
- 0, /* O_md14 */
- 0, /* O_md15 */
- 0, /* O_md16 */
};
/* Unfortunately, in MRI mode for the m68k, multiplication and
}
}
+void
+expr_set_rank (operatorT op, operator_rankT rank)
+{
+ gas_assert (op >= O_md1 && op < ARRAY_SIZE (op_rank));
+ op_rank[op] = rank;
+}
+
/* Initialize the expression parser. */
void
{
expressionS e;
e.X_op = O_max;
- assert (e.X_op == O_max);
+ gas_assert (e.X_op == O_max);
}
}
\f
Does not advance INPUT_LINE_POINTER. */
static inline operatorT
-operator (int *num_chars)
+operatorf (int *num_chars)
{
int c;
operatorT ret;
if (is_end_of_line[c])
return O_illegal;
+#ifdef md_operator
+ if (is_name_beginner (c))
+ {
+ char *name = input_line_pointer;
+ char ec = get_symbol_end ();
+
+ ret = md_operator (name, 2, &ec);
+ switch (ret)
+ {
+ case O_absent:
+ *input_line_pointer = ec;
+ input_line_pointer = name;
+ break;
+ case O_uminus:
+ case O_bit_not:
+ case O_logical_not:
+ as_bad (_("invalid use of operator \"%s\""), name);
+ ret = O_illegal;
+ /* FALLTHROUGH */
+ default:
+ *input_line_pointer = ec;
+ *num_chars = input_line_pointer - name;
+ input_line_pointer = name;
+ return ret;
+ }
+ }
+#endif
+
switch (c)
{
default:
+ ret = op_encoding[c];
+#ifdef md_operator
+ if (ret == O_illegal)
+ {
+ char *start = input_line_pointer;
+
+ ret = md_operator (NULL, 2, NULL);
+ if (ret != O_illegal)
+ *num_chars = input_line_pointer - start;
+ input_line_pointer = start;
+ }
+#endif
+ return ret;
+
+ case '+':
+ case '-':
return op_encoding[c];
case '<':
return ret;
case '!':
- /* We accept !! as equivalent to ^ for MRI compatibility. */
- if (input_line_pointer[1] != '!')
+ switch (input_line_pointer[1])
{
+ case '!':
+ /* We accept !! as equivalent to ^ for MRI compatibility. */
+ *num_chars = 2;
+ return O_bit_exclusive_or;
+ case '=':
+ /* We accept != as equivalent to <>. */
+ *num_chars = 2;
+ return O_ne;
+ default:
if (flag_m68k_mri)
return O_bit_inclusive_or;
return op_encoding[c];
}
- *num_chars = 2;
- return O_bit_exclusive_or;
case '|':
if (input_line_pointer[1] != '|')
/* NOTREACHED */
}
+/* Implement "word-size + 1 bit" addition for
+ {resultP->X_extrabit:resultP->X_add_number} + {rhs_highbit:amount}. This
+ is used so that the full range of unsigned word values and the full range of
+ signed word values can be represented in an O_constant expression, which is
+ useful e.g. for .sleb128 directives. */
+
+void
+add_to_result (expressionS *resultP, offsetT amount, int rhs_highbit)
+{
+ valueT ures = resultP->X_add_number;
+ valueT uamount = amount;
+
+ resultP->X_add_number += amount;
+
+ resultP->X_extrabit ^= rhs_highbit;
+
+ if (ures + uamount < ures)
+ resultP->X_extrabit ^= 1;
+}
+
+/* Similarly, for subtraction. */
+
+void
+subtract_from_result (expressionS *resultP, offsetT amount, int rhs_highbit)
+{
+ valueT ures = resultP->X_add_number;
+ valueT uamount = amount;
+
+ resultP->X_add_number -= amount;
+
+ resultP->X_extrabit ^= rhs_highbit;
+
+ if (ures < uamount)
+ resultP->X_extrabit ^= 1;
+}
+
/* Parse an expression. */
segT
expr (int rankarg, /* Larger # is higher rank. */
- expressionS *resultP /* Deliver result here. */)
+ expressionS *resultP, /* Deliver result here. */
+ enum expr_mode mode /* Controls behavior. */)
{
operator_rankT rank = (operator_rankT) rankarg;
segT retval;
operatorT op_right;
int op_chars;
- know (rank >= 0);
+ know (rankarg >= 0);
/* Save the value of dot for the fixup code. */
if (rank == 0)
- dot_value = frag_now_fix ();
+ {
+ dot_value = frag_now_fix ();
+ dot_frag = frag_now;
+ }
- retval = operand (resultP);
+ retval = operand (resultP, mode);
/* operand () gobbles spaces. */
know (*input_line_pointer != ' ');
- op_left = operator (&op_chars);
+ op_left = operatorf (&op_chars);
while (op_left != O_illegal && op_rank[(int) op_left] > rank)
{
segT rightseg;
+ offsetT frag_off;
input_line_pointer += op_chars; /* -> after operator. */
- rightseg = expr (op_rank[(int) op_left], &right);
+ right.X_md = 0;
+ rightseg = expr (op_rank[(int) op_left], &right, mode);
if (right.X_op == O_absent)
{
as_warn (_("missing operand; zero assumed"));
}
}
- op_right = operator (&op_chars);
+ op_right = operatorf (&op_chars);
- know (op_right == O_illegal
+ know (op_right == O_illegal || op_left == O_index
|| op_rank[(int) op_right] <= op_rank[(int) op_left]);
- know ((int) op_left >= (int) O_multiply
- && (int) op_left <= (int) O_logical_or);
+ know ((int) op_left >= (int) O_multiply);
+#ifndef md_operator
+ know ((int) op_left <= (int) O_index);
+#else
+ know ((int) op_left < (int) O_max);
+#endif
/* input_line_pointer->after right-hand quantity. */
/* left-hand quantity in resultP. */
}
else
#endif
- if (op_left == O_add && right.X_op == O_constant)
+#ifndef md_register_arithmetic
+# define md_register_arithmetic 1
+#endif
+ if (op_left == O_add && right.X_op == O_constant
+ && (md_register_arithmetic || resultP->X_op != O_register))
{
/* X + constant. */
- resultP->X_add_number += right.X_add_number;
+ add_to_result (resultP, right.X_add_number, right.X_extrabit);
}
/* This case comes up in PIC code. */
else if (op_left == O_subtract
&& right.X_op == O_symbol
&& resultP->X_op == O_symbol
- && (symbol_get_frag (right.X_add_symbol)
- == symbol_get_frag (resultP->X_add_symbol))
- && (SEG_NORMAL (rightseg)
- || right.X_add_symbol == resultP->X_add_symbol))
+ && retval == rightseg
+#ifdef md_allow_local_subtract
+ && md_allow_local_subtract (resultP, & right, rightseg)
+#endif
+ && ((SEG_NORMAL (rightseg)
+ && !S_FORCE_RELOC (resultP->X_add_symbol, 0)
+ && !S_FORCE_RELOC (right.X_add_symbol, 0))
+ || right.X_add_symbol == resultP->X_add_symbol)
+ && frag_offset_fixed_p (symbol_get_frag (resultP->X_add_symbol),
+ symbol_get_frag (right.X_add_symbol),
+ &frag_off))
{
- resultP->X_add_number -= right.X_add_number;
- resultP->X_add_number += (S_GET_VALUE (resultP->X_add_symbol)
- - S_GET_VALUE (right.X_add_symbol));
+ offsetT symval_diff = S_GET_VALUE (resultP->X_add_symbol)
+ - S_GET_VALUE (right.X_add_symbol);
+ subtract_from_result (resultP, right.X_add_number, right.X_extrabit);
+ subtract_from_result (resultP, frag_off / OCTETS_PER_BYTE, 0);
+ add_to_result (resultP, symval_diff, symval_diff < 0);
resultP->X_op = O_constant;
resultP->X_add_symbol = 0;
}
- else if (op_left == O_subtract && right.X_op == O_constant)
+ else if (op_left == O_subtract && right.X_op == O_constant
+ && (md_register_arithmetic || resultP->X_op != O_register))
{
/* X - constant. */
- resultP->X_add_number -= right.X_add_number;
+ subtract_from_result (resultP, right.X_add_number, right.X_extrabit);
}
- else if (op_left == O_add && resultP->X_op == O_constant)
+ else if (op_left == O_add && resultP->X_op == O_constant
+ && (md_register_arithmetic || right.X_op != O_register))
{
/* Constant + X. */
resultP->X_op = right.X_op;
resultP->X_add_symbol = right.X_add_symbol;
resultP->X_op_symbol = right.X_op_symbol;
- resultP->X_add_number += right.X_add_number;
+ add_to_result (resultP, right.X_add_number, right.X_extrabit);
retval = rightseg;
}
else if (resultP->X_op == O_constant && right.X_op == O_constant)
as_warn (_("division by zero"));
v = 1;
}
+ if ((valueT) v >= sizeof(valueT) * CHAR_BIT
+ && (op_left == O_left_shift || op_left == O_right_shift))
+ {
+ as_warn_value_out_of_range (_("shift count"), v, 0,
+ sizeof(valueT) * CHAR_BIT - 1,
+ NULL, 0);
+ resultP->X_add_number = v = 0;
+ }
switch (op_left)
{
- default: abort ();
+ default: goto general;
case O_multiply: resultP->X_add_number *= v; break;
case O_divide: resultP->X_add_number /= v; break;
case O_modulus: resultP->X_add_number %= v; break;
case O_bit_or_not: resultP->X_add_number |= ~v; break;
case O_bit_exclusive_or: resultP->X_add_number ^= v; break;
case O_bit_and: resultP->X_add_number &= v; break;
- case O_add: resultP->X_add_number += v; break;
- case O_subtract: resultP->X_add_number -= v; break;
+ /* Constant + constant (O_add) is handled by the
+ previous if statement for constant + X, so is omitted
+ here. */
+ case O_subtract:
+ subtract_from_result (resultP, v, 0);
+ break;
case O_eq:
resultP->X_add_number =
resultP->X_add_number == v ? ~ (offsetT) 0 : 0;
resultP->X_op = op_left;
resultP->X_op_symbol = right.X_add_symbol;
if (op_left == O_add)
- resultP->X_add_number += right.X_add_number;
+ add_to_result (resultP, right.X_add_number, right.X_extrabit);
else if (op_left == O_subtract)
{
- resultP->X_add_number -= right.X_add_number;
- if (retval == rightseg && SEG_NORMAL (retval))
+ subtract_from_result (resultP, right.X_add_number,
+ right.X_extrabit);
+ if (retval == rightseg
+ && SEG_NORMAL (retval)
+ && !S_FORCE_RELOC (resultP->X_add_symbol, 0)
+ && !S_FORCE_RELOC (right.X_add_symbol, 0))
{
retval = absolute_section;
rightseg = absolute_section;
}
else
{
+ general:
/* The general case. */
resultP->X_add_symbol = make_expr_symbol (resultP);
resultP->X_op_symbol = make_expr_symbol (&right);
resultP->X_op = op_left;
resultP->X_add_number = 0;
resultP->X_unsigned = 1;
+ resultP->X_extrabit = 0;
}
if (retval != rightseg)
{
- if (! SEG_NORMAL (retval))
- {
- if (retval != undefined_section || SEG_NORMAL (rightseg))
- retval = rightseg;
- }
- else if (SEG_NORMAL (rightseg)
+ if (retval == undefined_section)
+ ;
+ else if (rightseg == undefined_section)
+ retval = rightseg;
+ else if (retval == expr_section)
+ ;
+ else if (rightseg == expr_section)
+ retval = rightseg;
+ else if (retval == reg_section)
+ ;
+ else if (rightseg == reg_section)
+ retval = rightseg;
+ else if (rightseg == absolute_section)
+ ;
+ else if (retval == absolute_section)
+ retval = rightseg;
#ifdef DIFF_EXPR_OK
- && op_left != O_subtract
+ else if (op_left == O_subtract)
+ ;
#endif
- )
+ else
as_bad (_("operation combines symbols in different segments"));
}
if (resultP->X_add_symbol)
symbol_mark_used (resultP->X_add_symbol);
+ if (rank == 0 && mode == expr_evaluate)
+ resolve_expression (resultP);
+
return resultP->X_op == O_constant ? absolute_section : retval;
}
+
+/* Resolve an expression without changing any symbols/sub-expressions
+ used. */
+
+int
+resolve_expression (expressionS *expressionP)
+{
+ /* Help out with CSE. */
+ valueT final_val = expressionP->X_add_number;
+ symbolS *add_symbol = expressionP->X_add_symbol;
+ symbolS *orig_add_symbol = add_symbol;
+ symbolS *op_symbol = expressionP->X_op_symbol;
+ operatorT op = expressionP->X_op;
+ valueT left, right;
+ segT seg_left, seg_right;
+ fragS *frag_left, *frag_right;
+ offsetT frag_off;
+
+ switch (op)
+ {
+ default:
+ return 0;
+
+ case O_constant:
+ case O_register:
+ left = 0;
+ break;
+
+ case O_symbol:
+ case O_symbol_rva:
+ if (!snapshot_symbol (&add_symbol, &left, &seg_left, &frag_left))
+ return 0;
+
+ break;
+
+ case O_uminus:
+ case O_bit_not:
+ case O_logical_not:
+ if (!snapshot_symbol (&add_symbol, &left, &seg_left, &frag_left))
+ return 0;
+
+ if (seg_left != absolute_section)
+ return 0;
+
+ if (op == O_logical_not)
+ left = !left;
+ else if (op == O_uminus)
+ left = -left;
+ else
+ left = ~left;
+ op = O_constant;
+ break;
+
+ case O_multiply:
+ case O_divide:
+ case O_modulus:
+ case O_left_shift:
+ case O_right_shift:
+ case O_bit_inclusive_or:
+ case O_bit_or_not:
+ case O_bit_exclusive_or:
+ case O_bit_and:
+ case O_add:
+ case O_subtract:
+ case O_eq:
+ case O_ne:
+ case O_lt:
+ case O_le:
+ case O_ge:
+ case O_gt:
+ case O_logical_and:
+ case O_logical_or:
+ if (!snapshot_symbol (&add_symbol, &left, &seg_left, &frag_left)
+ || !snapshot_symbol (&op_symbol, &right, &seg_right, &frag_right))
+ return 0;
+
+ /* Simplify addition or subtraction of a constant by folding the
+ constant into X_add_number. */
+ if (op == O_add)
+ {
+ if (seg_right == absolute_section)
+ {
+ final_val += right;
+ op = O_symbol;
+ break;
+ }
+ else if (seg_left == absolute_section)
+ {
+ final_val += left;
+ left = right;
+ seg_left = seg_right;
+ add_symbol = op_symbol;
+ orig_add_symbol = expressionP->X_op_symbol;
+ op = O_symbol;
+ break;
+ }
+ }
+ else if (op == O_subtract)
+ {
+ if (seg_right == absolute_section)
+ {
+ final_val -= right;
+ op = O_symbol;
+ break;
+ }
+ }
+
+ /* Equality and non-equality tests are permitted on anything.
+ Subtraction, and other comparison operators are permitted if
+ both operands are in the same section.
+ Shifts by constant zero are permitted on anything.
+ Multiplies, bit-ors, and bit-ands with constant zero are
+ permitted on anything.
+ Multiplies and divides by constant one are permitted on
+ anything.
+ Binary operations with both operands being the same register
+ or undefined symbol are permitted if the result doesn't depend
+ on the input value.
+ Otherwise, both operands must be absolute. We already handled
+ the case of addition or subtraction of a constant above. */
+ frag_off = 0;
+ if (!(seg_left == absolute_section
+ && seg_right == absolute_section)
+ && !(op == O_eq || op == O_ne)
+ && !((op == O_subtract
+ || op == O_lt || op == O_le || op == O_ge || op == O_gt)
+ && seg_left == seg_right
+ && (finalize_syms
+ || frag_offset_fixed_p (frag_left, frag_right, &frag_off))
+ && (seg_left != reg_section || left == right)
+ && (seg_left != undefined_section || add_symbol == op_symbol)))
+ {
+ if ((seg_left == absolute_section && left == 0)
+ || (seg_right == absolute_section && right == 0))
+ {
+ if (op == O_bit_exclusive_or || op == O_bit_inclusive_or)
+ {
+ if (!(seg_right == absolute_section && right == 0))
+ {
+ seg_left = seg_right;
+ left = right;
+ add_symbol = op_symbol;
+ orig_add_symbol = expressionP->X_op_symbol;
+ }
+ op = O_symbol;
+ break;
+ }
+ else if (op == O_left_shift || op == O_right_shift)
+ {
+ if (!(seg_left == absolute_section && left == 0))
+ {
+ op = O_symbol;
+ break;
+ }
+ }
+ else if (op != O_multiply
+ && op != O_bit_or_not && op != O_bit_and)
+ return 0;
+ }
+ else if (op == O_multiply
+ && seg_left == absolute_section && left == 1)
+ {
+ seg_left = seg_right;
+ left = right;
+ add_symbol = op_symbol;
+ orig_add_symbol = expressionP->X_op_symbol;
+ op = O_symbol;
+ break;
+ }
+ else if ((op == O_multiply || op == O_divide)
+ && seg_right == absolute_section && right == 1)
+ {
+ op = O_symbol;
+ break;
+ }
+ else if (!(left == right
+ && ((seg_left == reg_section && seg_right == reg_section)
+ || (seg_left == undefined_section
+ && seg_right == undefined_section
+ && add_symbol == op_symbol))))
+ return 0;
+ else if (op == O_bit_and || op == O_bit_inclusive_or)
+ {
+ op = O_symbol;
+ break;
+ }
+ else if (op != O_bit_exclusive_or && op != O_bit_or_not)
+ return 0;
+ }
+
+ right += frag_off / OCTETS_PER_BYTE;
+ switch (op)
+ {
+ case O_add: left += right; break;
+ case O_subtract: left -= right; break;
+ case O_multiply: left *= right; break;
+ case O_divide:
+ if (right == 0)
+ return 0;
+ left = (offsetT) left / (offsetT) right;
+ break;
+ case O_modulus:
+ if (right == 0)
+ return 0;
+ left = (offsetT) left % (offsetT) right;
+ break;
+ case O_left_shift: left <<= right; break;
+ case O_right_shift: left >>= right; break;
+ case O_bit_inclusive_or: left |= right; break;
+ case O_bit_or_not: left |= ~right; break;
+ case O_bit_exclusive_or: left ^= right; break;
+ case O_bit_and: left &= right; break;
+ case O_eq:
+ case O_ne:
+ left = (left == right
+ && seg_left == seg_right
+ && (finalize_syms || frag_left == frag_right)
+ && (seg_left != undefined_section
+ || add_symbol == op_symbol)
+ ? ~ (valueT) 0 : 0);
+ if (op == O_ne)
+ left = ~left;
+ break;
+ case O_lt:
+ left = (offsetT) left < (offsetT) right ? ~ (valueT) 0 : 0;
+ break;
+ case O_le:
+ left = (offsetT) left <= (offsetT) right ? ~ (valueT) 0 : 0;
+ break;
+ case O_ge:
+ left = (offsetT) left >= (offsetT) right ? ~ (valueT) 0 : 0;
+ break;
+ case O_gt:
+ left = (offsetT) left > (offsetT) right ? ~ (valueT) 0 : 0;
+ break;
+ case O_logical_and: left = left && right; break;
+ case O_logical_or: left = left || right; break;
+ default: abort ();
+ }
+
+ op = O_constant;
+ break;
+ }
+
+ if (op == O_symbol)
+ {
+ if (seg_left == absolute_section)
+ op = O_constant;
+ else if (seg_left == reg_section && final_val == 0)
+ op = O_register;
+ else if (!symbol_same_p (add_symbol, orig_add_symbol))
+ final_val += left;
+ expressionP->X_add_symbol = add_symbol;
+ }
+ expressionP->X_op = op;
+
+ if (op == O_constant || op == O_register)
+ final_val += left;
+ expressionP->X_add_number = final_val;
+
+ return 1;
+}
\f
/* This lives here because it belongs equally in expr.c & read.c.
expr.c is just a branch office read.c anyway, and putting it
get_single_number (void)
{
expressionS exp;
- operand (&exp);
+ operand (&exp, expr_normal);
return exp.X_add_number;
}