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authorIan Lance Taylor <ian@airs.com>1997-08-25 19:55:14 +0000
committerIan Lance Taylor <ian@airs.com>1997-08-25 19:55:14 +0000
commit2051ec0e35f48e9b0134226032eb637000a450eb (patch)
treebfa4d6f44195fe0e548c149e5aaf012f43c6a002 /gas/symbols.c
parenta77b3837e3bf4541a1c8047f42ca5d66a17cca40 (diff)
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* symbols.c (resolve_symbol_value): Store the value back into the
symbol expression, to handle add or subtract simplification correctly. Handle O_symbol_rva. Add default case.
Diffstat (limited to 'gas/symbols.c')
-rw-r--r--gas/symbols.c294
1 files changed, 172 insertions, 122 deletions
diff --git a/gas/symbols.c b/gas/symbols.c
index 161f83b..d6dc8a4 100644
--- a/gas/symbols.c
+++ b/gas/symbols.c
@@ -236,7 +236,7 @@ colon (sym_name) /* just seen "x:" - rattle symbols & frags */
/*
* Now check for undefined symbols
*/
- if (!S_IS_DEFINED (symbolP))
+ if (!S_IS_DEFINED (symbolP) || S_IS_COMMON (symbolP))
{
if (S_GET_VALUE (symbolP) == 0)
{
@@ -265,7 +265,7 @@ colon (sym_name) /* just seen "x:" - rattle symbols & frags */
*/
if (((!S_IS_DEBUG (symbolP)
- && !S_IS_DEFINED (symbolP)
+ && (!S_IS_DEFINED (symbolP) || S_IS_COMMON (symbolP))
&& S_IS_EXTERNAL (symbolP))
|| S_GET_SEGMENT (symbolP) == bss_section)
&& (now_seg == data_section
@@ -353,6 +353,9 @@ colon (sym_name) /* just seen "x:" - rattle symbols & frags */
#ifdef tc_frob_label
tc_frob_label (symbolP);
#endif
+#ifdef obj_frob_label
+ obj_frob_label (symbolP);
+#endif
return symbolP;
}
@@ -633,87 +636,81 @@ verify_symbol_chain_2 (sym)
pass over the symbol table to resolve any symbols with complex
values. */
-void
-resolve_symbol_value (symp)
+valueT
+resolve_symbol_value (symp, finalize)
symbolS *symp;
+ int finalize;
{
int resolved;
+ valueT final_val;
+ segT final_seg;
if (symp->sy_resolved)
- return;
+ {
+ if (symp->sy_value.X_op == O_constant)
+ return (valueT) symp->sy_value.X_add_number;
+ else
+ return 0;
+ }
resolved = 0;
+ final_seg = S_GET_SEGMENT (symp);
if (symp->sy_resolving)
{
- as_bad ("Symbol definition loop encountered at %s",
- S_GET_NAME (symp));
- S_SET_VALUE (symp, (valueT) 0);
+ if (finalize)
+ as_bad ("Symbol definition loop encountered at %s", S_GET_NAME (symp));
+ final_val = 0;
resolved = 1;
}
else
{
- offsetT left, right, val;
+ symbolS *add_symbol, *op_symbol;
+ offsetT left, right;
segT seg_left, seg_right;
+ operatorT op;
symp->sy_resolving = 1;
- /* Simplify addition or subtraction of a constant by folding the
- constant into X_add_number. */
- if (symp->sy_value.X_op == O_add
- || symp->sy_value.X_op == O_subtract)
- {
- resolve_symbol_value (symp->sy_value.X_add_symbol);
- resolve_symbol_value (symp->sy_value.X_op_symbol);
- if (S_GET_SEGMENT (symp->sy_value.X_op_symbol) == absolute_section)
- {
- right = S_GET_VALUE (symp->sy_value.X_op_symbol);
- if (symp->sy_value.X_op == O_add)
- symp->sy_value.X_add_number += right;
- else
- symp->sy_value.X_add_number -= right;
- symp->sy_value.X_op = O_symbol;
- symp->sy_value.X_op_symbol = NULL;
- }
- else if ((S_GET_SEGMENT (symp->sy_value.X_add_symbol)
- == absolute_section)
- && symp->sy_value.X_op == O_add)
- {
- left = S_GET_VALUE (symp->sy_value.X_add_symbol);
- symp->sy_value.X_add_symbol = symp->sy_value.X_op_symbol;
- symp->sy_value.X_add_number += left;
- symp->sy_value.X_op = O_symbol;
- symp->sy_value.X_op_symbol = NULL;
- }
- }
+ /* Help out with CSE. */
+ add_symbol = symp->sy_value.X_add_symbol;
+ op_symbol = symp->sy_value.X_op_symbol;
+ final_val = symp->sy_value.X_add_number;
+ op = symp->sy_value.X_op;
- switch (symp->sy_value.X_op)
+ switch (op)
{
+ default:
+ BAD_CASE (op);
+ break;
+
case O_absent:
- S_SET_VALUE (symp, 0);
+ final_val = 0;
/* Fall through. */
+
case O_constant:
- S_SET_VALUE (symp, S_GET_VALUE (symp) + symp->sy_frag->fr_address);
- if (S_GET_SEGMENT (symp) == expr_section)
- S_SET_SEGMENT (symp, absolute_section);
+ final_val += symp->sy_frag->fr_address;
+ if (final_seg == expr_section)
+ final_seg = absolute_section;
resolved = 1;
break;
case O_symbol:
- resolve_symbol_value (symp->sy_value.X_add_symbol);
+ case O_symbol_rva:
+ left = resolve_symbol_value (add_symbol, finalize);
+ do_symbol:
if (symp->sy_mri_common)
{
/* This is a symbol inside an MRI common section. The
relocation routines are going to handle it specially.
Don't change the value. */
- S_SET_VALUE (symp, symp->sy_value.X_add_number);
- resolved = symp->sy_value.X_add_symbol->sy_resolved;
+ resolved = add_symbol->sy_resolved;
break;
}
- if (symp->sy_value.X_add_number == 0)
- copy_symbol_attributes (symp, symp->sy_value.X_add_symbol);
+ if (finalize && final_val == 0)
+ copy_symbol_attributes (symp, add_symbol);
/* If we have equated this symbol to an undefined symbol, we
keep X_op set to O_symbol, and we don't change
@@ -721,46 +718,45 @@ resolve_symbol_value (symp)
relocation to detect this case, and convert the
relocation to be against the symbol to which this symbol
is equated. */
- if (! S_IS_DEFINED (symp->sy_value.X_add_symbol)
- || S_IS_COMMON (symp->sy_value.X_add_symbol))
+ if (! S_IS_DEFINED (add_symbol) || S_IS_COMMON (add_symbol))
{
- symp->sy_value.X_op = O_symbol;
- S_SET_SEGMENT (symp,
- S_GET_SEGMENT (symp->sy_value.X_add_symbol));
+ if (finalize)
+ {
+ symp->sy_value.X_op = O_symbol;
+ S_SET_SEGMENT (symp, S_GET_SEGMENT (add_symbol));
+ }
+ symp->sy_value.X_add_number = final_val;
+ final_val = 0;
+ resolved = add_symbol->sy_resolved;
+ goto exit_dont_set_value;
}
else
{
- S_SET_VALUE (symp,
- (symp->sy_value.X_add_number
- + symp->sy_frag->fr_address
- + S_GET_VALUE (symp->sy_value.X_add_symbol)));
- if (S_GET_SEGMENT (symp) == expr_section
- || S_GET_SEGMENT (symp) == undefined_section)
- S_SET_SEGMENT (symp,
- S_GET_SEGMENT (symp->sy_value.X_add_symbol));
+ final_val += symp->sy_frag->fr_address + left;
+ if (final_seg == expr_section || final_seg == undefined_section)
+ final_seg = S_GET_SEGMENT (add_symbol);
}
- resolved = symp->sy_value.X_add_symbol->sy_resolved;
+ resolved = add_symbol->sy_resolved;
break;
case O_uminus:
case O_bit_not:
case O_logical_not:
- resolve_symbol_value (symp->sy_value.X_add_symbol);
- if (symp->sy_value.X_op == O_uminus)
- val = - S_GET_VALUE (symp->sy_value.X_add_symbol);
- else if (symp->sy_value.X_op == O_logical_not)
- val = ! S_GET_VALUE (symp->sy_value.X_add_symbol);
+ left = resolve_symbol_value (add_symbol, finalize);
+
+ if (op == O_uminus)
+ left = -left;
+ else if (op == O_logical_not)
+ left = !left;
else
- val = ~ S_GET_VALUE (symp->sy_value.X_add_symbol);
- S_SET_VALUE (symp,
- (val
- + symp->sy_value.X_add_number
- + symp->sy_frag->fr_address));
- if (S_GET_SEGMENT (symp) == expr_section
- || S_GET_SEGMENT (symp) == undefined_section)
- S_SET_SEGMENT (symp, absolute_section);
- resolved = symp->sy_value.X_add_symbol->sy_resolved;
+ left = ~left;
+
+ final_val += left + symp->sy_frag->fr_address;
+ if (final_seg == expr_section || final_seg == undefined_section)
+ final_seg = absolute_section;
+
+ resolved = add_symbol->sy_resolved;
break;
case O_multiply:
@@ -782,12 +778,35 @@ resolve_symbol_value (symp)
case O_gt:
case O_logical_and:
case O_logical_or:
- resolve_symbol_value (symp->sy_value.X_add_symbol);
- resolve_symbol_value (symp->sy_value.X_op_symbol);
- seg_left = S_GET_SEGMENT (symp->sy_value.X_add_symbol);
- seg_right = S_GET_SEGMENT (symp->sy_value.X_op_symbol);
- left = S_GET_VALUE (symp->sy_value.X_add_symbol);
- right = S_GET_VALUE (symp->sy_value.X_op_symbol);
+ left = resolve_symbol_value (add_symbol, finalize);
+ right = resolve_symbol_value (op_symbol, finalize);
+ seg_left = S_GET_SEGMENT (add_symbol);
+ seg_right = S_GET_SEGMENT (op_symbol);
+
+ /* Simplify addition or subtraction of a constant by folding the
+ constant into X_add_number. */
+ if (op == O_add || op == O_subtract)
+ {
+ if (seg_right == absolute_section)
+ {
+ if (op == O_add)
+ final_val += right;
+ else
+ final_val -= right;
+ op = O_symbol;
+ op_symbol = NULL;
+ goto do_symbol;
+ }
+ else if (seg_left == absolute_section && op == O_add)
+ {
+ op = O_symbol;
+ final_val += left;
+ add_symbol = op_symbol;
+ left = right;
+ op_symbol = NULL;
+ goto do_symbol;
+ }
+ }
/* Subtraction is permitted if both operands are in the same
section. Otherwise, both operands must be absolute. We
@@ -795,10 +814,11 @@ resolve_symbol_value (symp)
constant above. This will probably need to be changed
for an object file format which supports arbitrary
expressions, such as IEEE-695. */
- if ((seg_left != absolute_section
- || seg_right != absolute_section)
- && (symp->sy_value.X_op != O_subtract
- || seg_left != seg_right))
+ /* Don't emit messages unless we're finalizing the symbol value,
+ otherwise we may get the same message multiple times. */
+ if ((seg_left != absolute_section || seg_right != absolute_section)
+ && (op != O_subtract || seg_left != seg_right)
+ && finalize)
{
char *file;
unsigned int line;
@@ -834,38 +854,54 @@ resolve_symbol_value (symp)
}
}
+ /* Check for division by zero. */
+ if ((op == O_divide || op == O_modulus) && right == 0)
+ {
+ /* If seg_right is not absolute_section, then we've
+ already issued a warning about using a bad symbol. */
+ if (seg_right == absolute_section && finalize)
+ {
+ char *file;
+ unsigned int line;
+
+ if (expr_symbol_where (symp, &file, &line))
+ as_bad_where (file, line, "division by zero");
+ else
+ as_bad ("division by zero when setting %s",
+ S_GET_NAME (symp));
+ }
+
+ right = 1;
+ }
+
switch (symp->sy_value.X_op)
{
- case O_multiply: val = left * right; break;
- case O_divide: val = left / right; break;
- case O_modulus: val = left % right; break;
- case O_left_shift: val = left << right; break;
- case O_right_shift: val = left >> right; break;
- case O_bit_inclusive_or: val = left | right; break;
- case O_bit_or_not: val = left |~ right; break;
- case O_bit_exclusive_or: val = left ^ right; break;
- case O_bit_and: val = left & right; break;
- case O_add: val = left + right; break;
- case O_subtract: val = left - right; break;
- case O_eq: val = left == right ? ~ (offsetT) 0 : 0;
- case O_ne: val = left != right ? ~ (offsetT) 0 : 0;
- case O_lt: val = left < right ? ~ (offsetT) 0 : 0;
- case O_le: val = left <= right ? ~ (offsetT) 0 : 0;
- case O_ge: val = left >= right ? ~ (offsetT) 0 : 0;
- case O_gt: val = left > right ? ~ (offsetT) 0 : 0;
- case O_logical_and: val = left && right; break;
- case O_logical_or: val = left || right; break;
- default: abort ();
+ case O_multiply: left *= right; break;
+ case O_divide: left /= right; break;
+ case O_modulus: left %= 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_add: left += right; break;
+ case O_subtract: left -= right; break;
+ case O_eq: left = left == right ? ~ (offsetT) 0 : 0;
+ case O_ne: left = left != right ? ~ (offsetT) 0 : 0;
+ case O_lt: left = left < right ? ~ (offsetT) 0 : 0;
+ case O_le: left = left <= right ? ~ (offsetT) 0 : 0;
+ case O_ge: left = left >= right ? ~ (offsetT) 0 : 0;
+ case O_gt: left = left > right ? ~ (offsetT) 0 : 0;
+ case O_logical_and: left = left && right; break;
+ case O_logical_or: left = left || right; break;
+ default: abort ();
}
- S_SET_VALUE (symp,
- (symp->sy_value.X_add_number
- + symp->sy_frag->fr_address
- + val));
- if (S_GET_SEGMENT (symp) == expr_section
- || S_GET_SEGMENT (symp) == undefined_section)
- S_SET_SEGMENT (symp, absolute_section);
- resolved = (symp->sy_value.X_add_symbol->sy_resolved
- && symp->sy_value.X_op_symbol->sy_resolved);
+
+ final_val += symp->sy_frag->fr_address + left;
+ if (final_seg == expr_section || final_seg == undefined_section)
+ final_seg = absolute_section;
+ resolved = (add_symbol->sy_resolved && op_symbol->sy_resolved);
break;
case O_register:
@@ -878,16 +914,30 @@ resolve_symbol_value (symp)
anything. */
break;
}
+
+ symp->sy_resolving = 0;
}
+ if (finalize)
+ {
+ S_SET_VALUE (symp, final_val);
+ S_SET_SEGMENT (symp, final_seg);
+ }
+
+exit_dont_set_value:
/* Don't worry if we can't resolve an expr_section symbol. */
- if (resolved)
- symp->sy_resolved = 1;
- else if (S_GET_SEGMENT (symp) != expr_section)
+ if (finalize)
{
- as_bad ("can't resolve value for symbol \"%s\"", S_GET_NAME (symp));
- symp->sy_resolved = 1;
+ if (resolved)
+ symp->sy_resolved = 1;
+ else if (S_GET_SEGMENT (symp) != expr_section)
+ {
+ as_bad ("can't resolve value for symbol \"%s\"", S_GET_NAME (symp));
+ symp->sy_resolved = 1;
+ }
}
+
+ return final_val;
}
/* Dollar labels look like a number followed by a dollar sign. Eg, "42$".
@@ -1255,8 +1305,8 @@ valueT
S_GET_VALUE (s)
symbolS *s;
{
- if (!s->sy_resolved && !s->sy_resolving && s->sy_value.X_op != O_constant)
- resolve_symbol_value (s);
+ if (!s->sy_resolved && s->sy_value.X_op != O_constant)
+ resolve_symbol_value (s, 1);
if (s->sy_value.X_op != O_constant)
{
static symbolS *recur;
@@ -1296,7 +1346,7 @@ copy_symbol_attributes (dest, src)
#ifdef BFD_ASSEMBLER
/* In an expression, transfer the settings of these flags.
The user can override later, of course. */
-#define COPIED_SYMFLAGS (BSF_FUNCTION)
+#define COPIED_SYMFLAGS (BSF_FUNCTION | BSF_OBJECT)
dest->bsym->flags |= src->bsym->flags & COPIED_SYMFLAGS;
#endif