/* expr.c -operands, expressions-
Copyright 1987, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2002, 2003, 2004, 2005
+ 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
Free Software Foundation, Inc.
This file is part of GAS, the GNU Assembler.
static void mri_char_constant (expressionS *);
static void current_location (expressionS *);
static void clean_up_expression (expressionS * expressionP);
-static segT operand (expressionS *);
+static segT operand (expressionS *, enum expr_mode);
static operatorT operator (int *);
extern const char EXP_CHARS[], FLT_CHARS[];
{
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;
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. */
case '[':
#endif
/* Didn't begin with digit & not a name. */
- segment = expression (expressionP);
+ if (mode != expr_defer)
+ segment = expression (expressionP);
+ else
+ segment = deferred_expression (expressionP);
/* expression () will pass trailing whitespace. */
if ((c == '(' && *input_line_pointer != ')')
|| (c == '[' && *input_line_pointer != ']'))
if (0 && (c == '-' || c == '+') && *input_line_pointer == c)
goto target_op;
- operand (expressionP);
+ operand (expressionP, mode);
if (expressionP->X_op == O_constant)
{
/* input_line_pointer -> char after operand. */
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;
}
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)
{
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);
+ 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, __,
__, __, __, __, __, __, __, __,
__, __, __, __, __, __, __, __,
__, __, __, __, __, __, __, __,
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] != '|')
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;
if (rank == 0)
dot_value = frag_now_fix ();
- retval = operand (resultP);
+ retval = operand (resultP, mode);
/* operand () gobbles spaces. */
know (*input_line_pointer != ' ');
while (op_left != O_illegal && op_rank[(int) op_left] > rank)
{
segT rightseg;
+ bfd_vma frag_off;
input_line_pointer += op_chars; /* -> after operator. */
- rightseg = expr (op_rank[(int) op_left], &right);
+ rightseg = expr (op_rank[(int) op_left], &right, mode);
if (right.X_op == O_absent)
{
as_warn (_("missing operand; zero assumed"));
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))
+ && retval == rightseg
&& (SEG_NORMAL (rightseg)
- || right.X_add_symbol == resultP->X_add_symbol))
+ || 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 -= frag_off / OCTETS_PER_BYTE;
resultP->X_add_number += (S_GET_VALUE (resultP->X_add_symbol)
- S_GET_VALUE (right.X_add_symbol));
resultP->X_op = O_constant;
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 *op_symbol = expressionP->X_op_symbol;
+ operatorT op = expressionP->X_op;
+ valueT left, right;
+ segT seg_left, seg_right;
+ fragS *frag_left, *frag_right;
+ bfd_vma 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;
+ 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;
+ }
+ 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;
+ 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 (add_symbol != expressionP->X_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;
}
projects / deliverable / binutils-gdb.git / blobdiff