/* tc-mmix.c -- Assembler for Don Knuth's MMIX.
- Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007
- Free Software Foundation.
+ Copyright (C) 2001-2015 Free Software Foundation, Inc.
This file is part of GAS, the GNU Assembler.
compatible syntax, but the main purpose is to serve GCC. */
-#include <limits.h>
#include "as.h"
+#include <limits.h>
#include "subsegs.h"
#include "elf/mmix.h"
#include "opcode/mmix.h"
for example assert something of what it became or make a relocation. */
enum mmix_fixup_action
- {
- mmix_fixup_byte,
- mmix_fixup_register,
- mmix_fixup_register_or_adjust_for_byte
- };
+{
+ mmix_fixup_byte,
+ mmix_fixup_register,
+ mmix_fixup_register_or_adjust_for_byte
+};
static int get_spec_regno (char *);
static int get_operands (int, char *, expressionS *);
expressionS exp;
} mmix_raw_gregs[MAX_GREGS];
+static struct loc_assert_s
+ {
+ segT old_seg;
+ symbolS *loc_sym;
+ fragS *frag;
+ struct loc_assert_s *next;
+ } *loc_asserts = NULL;
+
/* Fixups for all unique GREG registers. We store the fixups here in
md_convert_frag, then we use the array to convert
BFD_RELOC_MMIX_BASE_PLUS_OFFSET fixups in tc_gen_reloc. The index is
pass expressions as symbols and use fix_new, not fix_new_exp. */
sym = make_expr_symbol (exp + 1);
+ /* Mark the symbol as being OK for a reloc. */
+ symbol_get_bfdsym (sym)->flags |= BSF_KEEP;
+
/* Now we know it can be a "base address plus offset". Add
proper fixup types so we can handle this later, when we've
parsed everything. */
break;
case mmix_operands_xyz_opt:
- /* SWYM, TRIP, TRAP: zero, one, two or three operands. */
+ /* SWYM, TRIP, TRAP: zero, one, two or three operands. It's
+ unspecified whether operands are registers or constants, but
+ when we find register syntax, we require operands to be literal and
+ within 0..255. */
if (n_operands == 0 && ! mmix_gnu_syntax)
/* Zeros are in place - nothing needs to be done for zero
operands. We don't allow this in GNU syntax mode, because it
{
if (exp[0].X_op == O_constant)
{
- if (exp[0].X_add_number > 255*255*255
+ if (exp[0].X_add_number > 255*256*256
|| exp[0].X_add_number < 0)
{
as_bad (_("invalid operands to opcode %s: `%s'"),
if (exp[1].X_op == O_constant)
{
- if (exp[1].X_add_number > 255*255
+ if (exp[1].X_add_number > 255*256
|| exp[1].X_add_number < 0)
{
as_bad (_("invalid operands to opcode %s: `%s'"),
fix_new_exp (opc_fragP, opcodep - opc_fragP->fr_literal + 3,
1, exp + 2, 0, BFD_RELOC_8);
}
- else if (n_operands <= 3
- && (strcmp (instruction->name, "trip") == 0
- || strcmp (instruction->name, "trap") == 0))
+ else
{
- /* The meaning of operands to TRIP and TRAP are not defined, so
- we add combinations not handled above here as we find them. */
+ /* We can't get here for other cases. */
+ gas_assert (n_operands <= 3);
+
+ /* The meaning of operands to TRIP and TRAP is not defined (and
+ SWYM operands aren't enforced in mmixal, so let's avoid
+ that). We add combinations not handled above here as we find
+ them and as they're reported. */
if (n_operands == 3)
{
/* Don't require non-register operands. Always generate
maintenance problems. TRIP is supposed to be a rare
instruction, so the overhead should not matter. We
aren't allowed to fix_new_exp for an expression which is
- an O_register at this point, however. */
+ an O_register at this point, however.
+
+ Don't use BFD_RELOC_MMIX_REG_OR_BYTE as that modifies
+ the insn for a register in the Z field and we want
+ consistency. */
if (exp[0].X_op == O_register)
opcodep[1] = exp[0].X_add_number;
else
fix_new_exp (opc_fragP, opcodep - opc_fragP->fr_literal + 1,
- 1, exp, 0, BFD_RELOC_MMIX_REG_OR_BYTE);
+ 1, exp, 0, BFD_RELOC_8);
if (exp[1].X_op == O_register)
opcodep[2] = exp[1].X_add_number;
else
fix_new_exp (opc_fragP, opcodep - opc_fragP->fr_literal + 2,
- 1, exp + 1, 0, BFD_RELOC_MMIX_REG_OR_BYTE);
+ 1, exp + 1, 0, BFD_RELOC_8);
if (exp[2].X_op == O_register)
opcodep[3] = exp[2].X_add_number;
else
fix_new_exp (opc_fragP, opcodep - opc_fragP->fr_literal + 3,
- 1, exp + 2, 0, BFD_RELOC_MMIX_REG_OR_BYTE);
+ 1, exp + 2, 0, BFD_RELOC_8);
}
else if (n_operands == 2)
{
if (exp[0].X_op == O_register)
- opcodep[2] = exp[0].X_add_number;
+ opcodep[1] = exp[0].X_add_number;
else
- fix_new_exp (opc_fragP, opcodep - opc_fragP->fr_literal + 2,
- 1, exp, 0, BFD_RELOC_MMIX_REG_OR_BYTE);
+ fix_new_exp (opc_fragP, opcodep - opc_fragP->fr_literal + 1,
+ 1, exp, 0, BFD_RELOC_8);
if (exp[1].X_op == O_register)
opcodep[3] = exp[1].X_add_number;
else
- fix_new_exp (opc_fragP, opcodep - opc_fragP->fr_literal + 3,
- 1, exp + 1, 0, BFD_RELOC_MMIX_REG_OR_BYTE);
+ fix_new_exp (opc_fragP, opcodep - opc_fragP->fr_literal + 2,
+ 2, exp + 1, 0, BFD_RELOC_16);
}
else
{
- as_bad (_("unsupported operands to %s: `%s'"),
- instruction->name, operands);
- return;
+ /* We can't get here for other cases. */
+ gas_assert (n_operands == 1 && exp[0].X_op == O_register);
+
+ opcodep[3] = exp[0].X_add_number;
}
}
- else
- {
- as_bad (_("invalid operands to opcode %s: `%s'"),
- instruction->name, operands);
- return;
- }
break;
case mmix_operands_resume:
mmix_greg_internal (char *label)
{
expressionS *expP = &mmix_raw_gregs[n_of_raw_gregs].exp;
+ segT section;
/* Don't set the section to register contents section before the
expression has been parsed; it may refer to the current position. */
- expression (expP);
+ section = expression (expP);
/* FIXME: Check that no expression refers to the register contents
section. May need to be done in elf64-mmix.c. */
expP->X_op_symbol = NULL;
}
+ if (section == undefined_section)
+ {
+ /* This is an error or a LOC with an expression involving
+ forward references. For the expression to be correctly
+ evaluated, we need to force a proper symbol; gas loses track
+ of the segment for "local symbols". */
+ if (expP->X_op == O_add)
+ {
+ symbol_get_value_expression (expP->X_op_symbol);
+ symbol_get_value_expression (expP->X_add_symbol);
+ }
+ else
+ {
+ gas_assert (expP->X_op == O_symbol);
+ symbol_get_value_expression (expP->X_add_symbol);
+ }
+ }
+
/* We must handle prefixes here, as we save the labels and expressions
to be output later. */
mmix_raw_gregs[n_of_raw_gregs].label
}
relP = (arelent *) xmalloc (sizeof (arelent));
- assert (relP != 0);
+ gas_assert (relP != 0);
relP->sym_ptr_ptr = (asymbol **) xmalloc (sizeof (asymbol *));
*relP->sym_ptr_ptr = baddsy;
relP->address = fixP->fx_frag->fr_address + fixP->fx_where;
it the same alignment and address as the associated instruction. */
/* Make room for the label including the ending nul. */
- int len_0 = s - label + 1;
+ size_t len_0 = s - label + 1;
/* Save this label on the MMIX symbol obstack. Saving it on an
obstack is needless for "IS"-pseudos, but it's harmless and we
{
fragS *fragP;
symbolS *mainsym;
+ asection *regsec;
+ struct loc_assert_s *loc_assert;
int i;
/* The first frag of GREG:s going into the register contents section. */
S_SET_EXTERNAL (mainsym);
}
+ /* Check that we didn't LOC into the unknown, or rather that when it
+ was unknown, we actually change sections. */
+ for (loc_assert = loc_asserts;
+ loc_assert != NULL;
+ loc_assert = loc_assert->next)
+ {
+ segT actual_seg;
+
+ resolve_symbol_value (loc_assert->loc_sym);
+ actual_seg = S_GET_SEGMENT (loc_assert->loc_sym);
+ if (actual_seg != loc_assert->old_seg)
+ {
+ char *fnam;
+ unsigned int line;
+ int e_valid = expr_symbol_where (loc_assert->loc_sym, &fnam, &line);
+
+ gas_assert (e_valid == 1);
+ as_bad_where (fnam, line,
+ _("LOC to section unknown or indeterminable "
+ "at first pass"));
+
+ /* Patch up the generic location data to avoid cascading
+ error messages from later passes. (See original in
+ write.c:relax_segment.) */
+ fragP = loc_assert->frag;
+ fragP->fr_type = rs_align;
+ fragP->fr_subtype = 0;
+ fragP->fr_offset = 0;
+ fragP->fr_fix = 0;
+ }
+ }
+
if (n_of_raw_gregs != 0)
{
/* Emit GREGs. They are collected in order of appearance, but must
and the same allocation order (within a file) as mmixal. */
segT this_segment = now_seg;
subsegT this_subsegment = now_subseg;
- asection *regsec
- = bfd_make_section_old_way (stdoutput,
- MMIX_REG_CONTENTS_SECTION_NAME);
+
+ regsec = bfd_make_section_old_way (stdoutput,
+ MMIX_REG_CONTENTS_SECTION_NAME);
subseg_set (regsec, 0);
/* Finally emit the initialization-value. Emit a variable frag, which
subseg_set (this_segment, this_subsegment);
}
+ regsec = bfd_get_section_by_name (stdoutput, MMIX_REG_CONTENTS_SECTION_NAME);
+ /* Mark the section symbol as being OK for a reloc. */
+ if (regsec != NULL)
+ regsec->symbol->flags |= BSF_KEEP;
+
/* Iterate over frags resulting from GREGs and move those that evidently
have the same value together and point one to another.
if (exp.X_op == O_illegal
|| exp.X_op == O_absent
- || exp.X_op == O_big
- || section == undefined_section)
+ || exp.X_op == O_big)
{
as_bad (_("invalid LOC expression"));
return;
}
+ if (section == undefined_section)
+ {
+ /* This is an error or a LOC with an expression involving
+ forward references. For the expression to be correctly
+ evaluated, we need to force a proper symbol; gas loses track
+ of the segment for "local symbols". */
+ if (exp.X_op == O_add)
+ {
+ symbol_get_value_expression (exp.X_op_symbol);
+ symbol_get_value_expression (exp.X_add_symbol);
+ }
+ else
+ {
+ gas_assert (exp.X_op == O_symbol);
+ symbol_get_value_expression (exp.X_add_symbol);
+ }
+ }
+
if (section == absolute_section)
{
/* Translate a constant into a suitable section. */
if (exp.X_add_number < ((offsetT) 0x20 << 56))
{
- /* Lower than Data_Segment - assume it's .text. */
+ /* Lower than Data_Segment or in the reserved area (the
+ segment number is >= 0x80, appearing negative) - assume
+ it's .text. */
section = text_section;
/* Save the lowest seen location, so we can pass on this
this one), we org at (this - lower). There's an implicit
"LOC 0" before any entered code. FIXME: handled by spurious
settings of text_has_contents. */
- if (exp.X_add_number < 0
- || exp.X_add_number < (offsetT) lowest_text_loc)
+ if (lowest_text_loc != (bfd_vma) -1
+ && (bfd_vma) exp.X_add_number < lowest_text_loc)
{
as_bad (_("LOC expression stepping backwards is not supported"));
exp.X_op = O_absent;
}
else
{
- /* Do the same for the .data section. */
+ /* Do the same for the .data section, except we don't have
+ to worry about exp.X_add_number carrying a sign. */
section = data_section;
if (exp.X_add_number < (offsetT) lowest_data_loc)
}
}
- if (section != now_seg)
+ /* If we can't deduce the section, it must be the current one.
+ Below, we arrange to assert this. */
+ if (section != now_seg && section != undefined_section)
{
obj_elf_section_change_hook ();
subseg_set (section, 0);
if (exp.X_op != O_absent)
{
+ symbolS *esym = NULL;
+
if (exp.X_op != O_constant && exp.X_op != O_symbol)
{
/* Handle complex expressions. */
- sym = make_expr_symbol (&exp);
+ esym = sym = make_expr_symbol (&exp);
off = 0;
}
else
{
sym = exp.X_add_symbol;
off = exp.X_add_number;
+
+ if (section == undefined_section)
+ {
+ /* We need an expr_symbol when tracking sections. In
+ order to make this an expr_symbol with file and line
+ tracked, we have to make the exp non-trivial; not an
+ O_symbol with .X_add_number == 0. The constant part
+ is unused. */
+ exp.X_add_number = 1;
+ esym = make_expr_symbol (&exp);
+ }
+ }
+
+ /* Track the LOC's where we couldn't deduce the section: assert
+ that we weren't supposed to change section. */
+ if (section == undefined_section)
+ {
+ struct loc_assert_s *next = loc_asserts;
+ loc_asserts
+ = (struct loc_assert_s *) xmalloc (sizeof (*loc_asserts));
+ loc_asserts->next = next;
+ loc_asserts->old_seg = now_seg;
+ loc_asserts->loc_sym = esym;
+ loc_asserts->frag = frag_now;
}
p = frag_var (rs_org, 1, 1, (relax_substateT) 0, sym, off, (char *) 0);
mmix_byte (void)
{
unsigned int c;
- char *start;
if (now_seg == text_section)
text_has_contents = 1;
{
case '\"':
++input_line_pointer;
- start = input_line_pointer;
while (is_a_char (c = next_char_of_string ()))
{
FRAG_APPEND_1_CHAR (c);
mmix_cons (int nbytes)
{
expressionS exp;
- char *start;
/* If we don't have any contents, then it's ok to have a specified start
address that is not a multiple of the max data size. We will then
bytes. */
case '\"':
++input_line_pointer;
- start = input_line_pointer;
while (is_a_char (c = next_char_of_string ()))
{
exp.X_op = O_constant;