/* tc-mmix.c -- Assembler for Don Knuth's MMIX.
- Copyright (C) 2001, 2002 Free Software Foundation.
+ Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation.
This file is part of GAS, the GNU Assembler.
#include <stdio.h>
+#include <limits.h>
#include "as.h"
#include "subsegs.h"
#include "bfd.h"
static void mmix_discard_rest_of_line PARAMS ((void));
static void mmix_byte PARAMS ((void));
static void mmix_cons PARAMS ((int));
-static void mmix_frob_local_reloc PARAMS ((bfd *, asection *, PTR));
/* Continue the tradition of symbols.c; use control characters to enforce
magic. These are used when replacing e.g. 8F and 8B so we can handle
this line? */
static int label_without_colon_this_line = 1;
-/* Should we expand operands for external symbols? */
+/* Should we automatically expand instructions into multiple insns in
+ order to generate working code? */
static int expand_op = 1;
/* Should we warn when expanding operands? FIXME: test-cases for when -x
/* Do we globalize all symbols? */
int mmix_globalize_symbols = 0;
+/* When expanding insns, do we want to expand PUSHJ as a call to a stub
+ (or else as a series of insns)? */
+int pushj_stubs = 1;
+
/* Do we know that the next semicolon is at the end of the operands field
- (in mmixal mode; constant 1 in GNU mode)? */
+ (in mmixal mode; constant 1 in GNU mode)? */
int mmix_next_semicolon_is_eoln = 1;
/* Do we have a BSPEC in progress? */
#define OPTION_GLOBALIZE_SYMBOLS (OPTION_GNU_SYNTAX + 1)
#define OPTION_FIXED_SPEC_REGS (OPTION_GLOBALIZE_SYMBOLS + 1)
#define OPTION_LINKER_ALLOCATED_GREGS (OPTION_FIXED_SPEC_REGS + 1)
+#define OPTION_NOPUSHJSTUBS (OPTION_LINKER_ALLOCATED_GREGS + 1)
{"linkrelax", no_argument, NULL, OPTION_RELAX},
{"no-expand", no_argument, NULL, OPTION_NOEXPAND},
{"no-merge-gregs", no_argument, NULL, OPTION_NOMERGEGREG},
OPTION_FIXED_SPEC_REGS},
{"linker-allocated-gregs", no_argument, NULL,
OPTION_LINKER_ALLOCATED_GREGS},
+ {"no-pushj-stubs", no_argument, NULL, OPTION_NOPUSHJSTUBS},
+ {"no-stubs", no_argument, NULL, OPTION_NOPUSHJSTUBS},
{NULL, no_argument, NULL, 0}
};
3. PUSHJ
extra length: zero or four insns.
+ Special handling to deal with transition to PUSHJSTUB.
4. JMP
- extra length: zero or four insns. */
+ extra length: zero or four insns.
+
+ 5. GREG
+ special handling, allocates a named global register unless another
+ is within reach for all uses.
+
+ 6. PUSHJSTUB
+ special handling (mostly) for external references; assumes the
+ linker will generate a stub if target is no longer than 256k from
+ the end of the section plus max size of previous stubs. Zero or
+ four insns. */
#define STATE_GETA (1)
#define STATE_BCC (2)
#define STATE_PUSHJ (3)
#define STATE_JMP (4)
#define STATE_GREG (5)
+#define STATE_PUSHJSTUB (6)
/* No fine-grainedness here. */
#define STATE_LENGTH_MASK (1)
#define STATE_GREG_UNDF ENCODE_RELAX (STATE_GREG, STATE_ZERO)
#define STATE_GREG_DEF ENCODE_RELAX (STATE_GREG, STATE_MAX)
-/* These displacements are relative to the adress following the opcode
+/* These displacements are relative to the address following the opcode
word of the instruction. The catch-all states have zero for "reach"
and "next" entries. */
#define PUSHJ_4F GETA_3F
#define PUSHJ_4B GETA_3B
+/* We'll very rarely have sections longer than LONG_MAX, but we'll make a
+ feeble attempt at getting 64-bit values. */
+#define PUSHJSTUB_MAX ((offsetT) (((addressT) -1) >> 1))
+#define PUSHJSTUB_MIN (-PUSHJSTUB_MAX - 1)
+
#define JMP_0F (65536 * 256 * 4 - 8)
#define JMP_0B (-65536 * 256 * 4 - 4)
{BCC_5F, BCC_5B,
BCC_MAX_LEN - 4, 0},
- /* PUSHJ (3, 0). */
- {PUSHJ_0F, PUSHJ_0B, 0, ENCODE_RELAX (STATE_PUSHJ, STATE_MAX)},
+ /* PUSHJ (3, 0). Next state is actually PUSHJSTUB (6, 0). */
+ {PUSHJ_0F, PUSHJ_0B, 0, ENCODE_RELAX (STATE_PUSHJSTUB, STATE_ZERO)},
/* PUSHJ (3, 1). */
{PUSHJ_4F, PUSHJ_4B,
JMP_MAX_LEN - 4, 0},
/* GREG (5, 0), (5, 1), though the table entry isn't used. */
- {0, 0, 0, 0}, {0, 0, 0, 0}
+ {0, 0, 0, 0}, {0, 0, 0, 0},
+
+ /* PUSHJSTUB (6, 0). PUSHJ (3, 0) uses the range, so we set it to infinite. */
+ {PUSHJSTUB_MAX, PUSHJSTUB_MIN,
+ 0, ENCODE_RELAX (STATE_PUSHJ, STATE_MAX)},
+ /* PUSHJSTUB (6, 1) isn't used. */
+ {0, 0, PUSHJ_MAX_LEN, 0}
};
const pseudo_typeS md_pseudo_table[] =
/* Support " .local $45" syntax. */
{"local", mmix_s_local, 1},
- /* Support DWARF2 debugging info. */
- {"file", (void (*) PARAMS ((int))) dwarf2_directive_file, 0},
- {"loc", dwarf2_directive_loc, 0},
-
{NULL, 0, 0}
};
input_line_pointer = p;
+ /* Initialize both possible operands to error state, in case we never
+ get further. */
+ exp[0].X_op = O_illegal;
+ exp[1].X_op = O_illegal;
+
if (insn->operands == mmix_operands_get)
{
expp_reg = &exp[0];
expp_sreg = &exp[0];
expp_reg = &exp[1];
- /* Initialize to error state in case we'll never call expression on
- this operand. */
- expp_reg->X_op = O_illegal;
-
sregp = p;
c = get_symbol_end ();
sregend = p = input_line_pointer;
allocate_undefined_gregs_in_linker = 1;
break;
+ case OPTION_NOPUSHJSTUBS:
+ pushj_stubs = 0;
+ break;
+
default:
return 0;
}
break;
case mmix_operands_jmp:
- /* A JMP. Everyhing is already done. */
+ /* A JMP. Everything is already done. */
break;
case mmix_operands_roundregs:
{
/* Don't require non-register operands. Always generate
fixups, so we don't have to copy lots of code and create
- maintanance problems. TRIP is supposed to be a rare
+ 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. */
{
HANDLE_RELAXABLE (STATE_GETA);
HANDLE_RELAXABLE (STATE_BCC);
- HANDLE_RELAXABLE (STATE_PUSHJ);
HANDLE_RELAXABLE (STATE_JMP);
+ case ENCODE_RELAX (STATE_PUSHJ, STATE_UNDF):
+ if (fragP->fr_symbol != NULL
+ && S_GET_SEGMENT (fragP->fr_symbol) == segment
+ && !S_IS_WEAK (fragP->fr_symbol))
+ /* The symbol lies in the same segment - a relaxable case. */
+ fragP->fr_subtype = ENCODE_RELAX (STATE_PUSHJ, STATE_ZERO);
+ else if (pushj_stubs)
+ /* If we're to generate stubs, assume we can reach a stub after
+ the section. */
+ fragP->fr_subtype = ENCODE_RELAX (STATE_PUSHJSTUB, STATE_ZERO);
+ /* FALLTHROUGH. */
+ case ENCODE_RELAX (STATE_PUSHJ, STATE_ZERO):
+ case ENCODE_RELAX (STATE_PUSHJSTUB, STATE_ZERO):
+ /* We need to distinguish different relaxation rounds. */
+ seg_info (segment)->tc_segment_info_data.last_stubfrag = fragP;
+ break;
+
case ENCODE_RELAX (STATE_GETA, STATE_ZERO):
case ENCODE_RELAX (STATE_BCC, STATE_ZERO):
- case ENCODE_RELAX (STATE_PUSHJ, STATE_ZERO):
case ENCODE_RELAX (STATE_JMP, STATE_ZERO):
/* When relaxing a section for the second time, we don't need to do
anything except making sure that fr_var is set right. */
switch (fragP->fr_subtype)
{
+ case ENCODE_RELAX (STATE_PUSHJSTUB, STATE_ZERO):
+ /* Setting the unknown bits to 0 seems the most appropriate. */
+ mmix_set_geta_branch_offset (opcodep, 0);
+ tmpfixP = fix_new (opc_fragP, opcodep - opc_fragP->fr_literal, 8,
+ fragP->fr_symbol, fragP->fr_offset, 1,
+ BFD_RELOC_MMIX_PUSHJ_STUBBABLE);
+ COPY_FR_WHERE_TO_FX (fragP, tmpfixP);
+ var_part_size = 0;
+ break;
+
case ENCODE_RELAX (STATE_GETA, STATE_ZERO):
case ENCODE_RELAX (STATE_BCC, STATE_ZERO):
case ENCODE_RELAX (STATE_PUSHJ, STATE_ZERO):
case STATE_GREG_DEF:
if (fragP->tc_frag_data == NULL)
{
+ /* We must initialize data that's supposed to be "fixed up" to
+ avoid emitting garbage, because md_apply_fix3 won't do
+ anything for undefined symbols. */
+ md_number_to_chars (var_partp, 0, 8);
tmpfixP
= fix_new (fragP, var_partp - fragP->fr_literal, 8,
fragP->fr_symbol, fragP->fr_offset, 0, BFD_RELOC_64);
case BFD_RELOC_MMIX_GETA:
case BFD_RELOC_MMIX_CBRANCH:
case BFD_RELOC_MMIX_PUSHJ:
+ case BFD_RELOC_MMIX_PUSHJ_STUBBABLE:
/* If this fixup is out of range, punt to the linker to emit an
error. This should only happen with -no-expand. */
if (val < -(((offsetT) 1 << 19)/2)
case BFD_RELOC_MMIX_PUSHJ_1:
case BFD_RELOC_MMIX_PUSHJ_2:
case BFD_RELOC_MMIX_PUSHJ_3:
+ case BFD_RELOC_MMIX_PUSHJ_STUBBABLE:
case BFD_RELOC_MMIX_JMP:
case BFD_RELOC_MMIX_JMP_1:
case BFD_RELOC_MMIX_JMP_2:
fixS *fixP;
{
if (fixP->fx_r_type == BFD_RELOC_MMIX_LOCAL
- || fixP->fx_r_type == BFD_RELOC_VTABLE_INHERIT
- || fixP->fx_r_type == BFD_RELOC_VTABLE_ENTRY
|| fixP->fx_r_type == BFD_RELOC_MMIX_BASE_PLUS_OFFSET)
return 1;
if (fixP->fx_pcrel)
return 1;
- return S_FORCE_RELOC (fixP->fx_addsy);
+ return generic_force_reloc (fixP);
}
/* The location from which a PC relative jump should be calculated,
fragS *fragP;
long stretch;
{
- if (fragP->fr_subtype != STATE_GREG_DEF
- && fragP->fr_subtype != STATE_GREG_UNDF)
- return relax_frag (seg, fragP, stretch);
+ switch (fragP->fr_subtype)
+ {
+ /* Growth for this type has been handled by mmix_md_end and
+ correctly estimated, so there's nothing more to do here. */
+ case STATE_GREG_DEF:
+ return 0;
- /* If we're defined, we don't grow. */
- if (fragP->fr_subtype == STATE_GREG_DEF)
- return 0;
+ case ENCODE_RELAX (STATE_PUSHJ, STATE_ZERO):
+ {
+ /* We need to handle relaxation type ourselves, since relax_frag
+ doesn't update fr_subtype if there's no size increase in the
+ current section; when going from plain PUSHJ to a stub. This
+ is otherwise functionally the same as relax_frag in write.c,
+ simplified for this case. */
+ offsetT aim;
+ addressT target;
+ addressT address;
+ symbolS *symbolP;
+ target = fragP->fr_offset;
+ address = fragP->fr_address;
+ symbolP = fragP->fr_symbol;
+
+ if (symbolP)
+ {
+ fragS *sym_frag;
+
+ sym_frag = symbol_get_frag (symbolP);
+ know (S_GET_SEGMENT (symbolP) != absolute_section
+ || sym_frag == &zero_address_frag);
+ target += S_GET_VALUE (symbolP);
+
+ /* If frag has yet to be reached on this pass, assume it will
+ move by STRETCH just as we did. If this is not so, it will
+ be because some frag between grows, and that will force
+ another pass. */
+
+ if (stretch != 0
+ && sym_frag->relax_marker != fragP->relax_marker
+ && S_GET_SEGMENT (symbolP) == seg)
+ target += stretch;
+ }
+
+ aim = target - address - fragP->fr_fix;
+ if (aim >= PUSHJ_0B && aim <= PUSHJ_0F)
+ {
+ /* Target is reachable with a PUSHJ. */
+ segment_info_type *seginfo = seg_info (seg);
+
+ /* If we're at the end of a relaxation round, clear the stub
+ counter as initialization for the next round. */
+ if (fragP == seginfo->tc_segment_info_data.last_stubfrag)
+ seginfo->tc_segment_info_data.nstubs = 0;
+ return 0;
+ }
+
+ /* Not reachable. Try a stub. */
+ fragP->fr_subtype = ENCODE_RELAX (STATE_PUSHJSTUB, STATE_ZERO);
+ }
+ /* FALLTHROUGH. */
+
+ /* See if this PUSHJ is redirectable to a stub. */
+ case ENCODE_RELAX (STATE_PUSHJSTUB, STATE_ZERO):
+ {
+ segment_info_type *seginfo = seg_info (seg);
+ fragS *lastfrag = seginfo->frchainP->frch_last;
+ relax_substateT prev_type = fragP->fr_subtype;
+
+ /* The last frag is always an empty frag, so it suffices to look
+ at its address to know the ending address of this section. */
+ know (lastfrag->fr_type == rs_fill
+ && lastfrag->fr_fix == 0
+ && lastfrag->fr_var == 0);
+
+ /* For this PUSHJ to be relaxable into a call to a stub, the
+ distance must be no longer than 256k bytes from the PUSHJ to
+ the end of the section plus the maximum size of stubs so far. */
+ if ((lastfrag->fr_address
+ + stretch
+ + PUSHJ_MAX_LEN * seginfo->tc_segment_info_data.nstubs)
+ - (fragP->fr_address + fragP->fr_fix)
+ > GETA_0F
+ || !pushj_stubs)
+ fragP->fr_subtype = mmix_relax_table[prev_type].rlx_more;
+ else
+ seginfo->tc_segment_info_data.nstubs++;
+
+ /* If we're at the end of a relaxation round, clear the stub
+ counter as initialization for the next round. */
+ if (fragP == seginfo->tc_segment_info_data.last_stubfrag)
+ seginfo->tc_segment_info_data.nstubs = 0;
+
+ return
+ (mmix_relax_table[fragP->fr_subtype].rlx_length
+ - mmix_relax_table[prev_type].rlx_length);
+ }
+
+ case ENCODE_RELAX (STATE_PUSHJ, STATE_MAX):
+ {
+ segment_info_type *seginfo = seg_info (seg);
+
+ /* Need to cover all STATE_PUSHJ states to act on the last stub
+ frag (the end of this relax round; initialization for the
+ next). */
+ if (fragP == seginfo->tc_segment_info_data.last_stubfrag)
+ seginfo->tc_segment_info_data.nstubs = 0;
+
+ return 0;
+ }
+
+ default:
+ return relax_frag (seg, fragP, stretch);
+
+ case STATE_GREG_UNDF:
+ BAD_CASE (fragP->fr_subtype);
+ }
as_fatal (_("internal: unexpected relax type %d:%d"),
fragP->fr_type, fragP->fr_subtype);
return 1;
}
-/* Worker for mmix_frob_file_before_adjust. */
-
-static void
-mmix_frob_local_reloc (abfd, sec, xxx)
- bfd *abfd ATTRIBUTE_UNUSED;
- asection *sec;
- PTR xxx ATTRIBUTE_UNUSED;
-{
- segment_info_type *seginfo = seg_info (sec);
- fixS *fixp;
-
- if (seginfo == NULL)
- return;
-
- for (fixp = seginfo->fix_root; fixp; fixp = fixp->fx_next)
- if (! fixp->fx_done && fixp->fx_addsy != NULL)
- {
- symbolS *sym = fixp->fx_addsy;
- asection *section = S_GET_SEGMENT (sym);
-
- if (section == reg_section
- && fixp->fx_r_type == BFD_RELOC_MMIX_LOCAL)
- {
- /* If the register is marked global, we don't need to replace
- with the *real* register section since that will be done
- when the symbol is changed. */
- if (! S_IS_EXTERNAL (sym))
- /* If it's a local symbol, we replace it with an anonymous
- one with the same constant value. */
- fixp->fx_addsy = expr_build_uconstant (S_GET_VALUE (sym));
- }
- }
-}
-
-/* Change fixups for register symbols for BFD_MMIX_LOCAL to be for an
- absolute symbol. */
-
-void
-mmix_frob_file_before_adjust ()
-{
- return;
- bfd_map_over_sections (stdoutput, mmix_frob_local_reloc, (char *) 0);
-}
-
/* Just check that we don't have a BSPEC/ESPEC pair active when changing
sections "normally", and get knowledge about alignment from the new
section. */
projects / deliverable / binutils-gdb.git / blobdiff