#endif
};
+/* A circular list of all potential and actual literal pool locations
+ in a segment. */
+struct litpool_frag
+{
+ struct litpool_frag *next;
+ struct litpool_frag *prev;
+ fragS *fragP;
+ addressT addr;
+ short priority; /* 1, 2, or 3 -- 1 is highest */
+ short original_priority;
+};
+
+/* Map a segment to its litpool_frag list. */
+struct litpool_seg
+{
+ struct litpool_seg *next;
+ asection *seg;
+ struct litpool_frag frag_list;
+ int frag_count; /* since last litpool location */
+};
+
+static struct litpool_seg litpool_seg_list;
+
/* Directive functions. */
static void xtensa_maybe_create_trampoline_frag (void);
struct trampoline_frag;
static int init_trampoline_frag (struct trampoline_frag *);
+static void xtensa_maybe_create_literal_pool_frag (bfd_boolean, bfd_boolean);
+static bfd_boolean auto_litpools = FALSE;
+static int auto_litpool_limit = 10000;
/* Alignment Functions. */
option_trampolines,
option_no_trampolines,
+
+ option_auto_litpools,
+ option_no_auto_litpools,
+ option_auto_litpool_limit,
};
const char *md_shortopts = "";
{ "trampolines", no_argument, NULL, option_trampolines },
{ "no-trampolines", no_argument, NULL, option_no_trampolines },
+ { "auto-litpools", no_argument, NULL, option_auto_litpools },
+ { "no-auto-litpools", no_argument, NULL, option_no_auto_litpools },
+ { "auto-litpool-limit", required_argument, NULL, option_auto_litpool_limit },
+
{ NULL, no_argument, NULL, 0 }
};
use_trampolines = FALSE;
return 1;
+ case option_auto_litpools:
+ auto_litpools = TRUE;
+ use_literal_section = FALSE;
+ return 1;
+
+ case option_no_auto_litpools:
+ auto_litpools = FALSE;
+ auto_litpool_limit = -1;
+ return 1;
+
+ case option_auto_litpool_limit:
+ {
+ int value = 0;
+ if (auto_litpool_limit < 0)
+ as_fatal (_("no-auto-litpools is incompatible with auto-litpool-limit"));
+ if (*arg == 0 || *arg == '-')
+ as_fatal (_("invalid auto-litpool-limit argument"));
+ value = strtol (arg, &arg, 10);
+ if (*arg != 0)
+ as_fatal (_("invalid auto-litpool-limit argument"));
+ if (value < 100 || value > 10000)
+ as_fatal (_("invalid auto-litpool-limit argument (range is 100-10000)"));
+ auto_litpool_limit = value;
+ auto_litpools = TRUE;
+ use_literal_section = FALSE;
+ return 1;
+ }
+
default:
return 0;
}
flix bundles\n\
--rename-section old=new Rename section 'old' to 'new'\n\
--[no-]trampolines [Do not] generate trampolines (jumps to jumps)\n\
- when jumps do not reach their targets\n", stream);
+ when jumps do not reach their targets\n\
+ --[no-]auto-litpools [Do not] automatically create literal pools\n\
+ --auto-litpool-limit=<value>\n\
+ (range 100-10000) Maximum number of blocks of\n\
+ instructions to emit between literal pool\n\
+ locations; implies --auto-litpools flag\n", stream);
}
\f
pool_location = frag_now;
frag_now->tc_frag_data.lit_frchain = frchain_now;
frag_now->tc_frag_data.literal_frag = frag_now;
+ /* Just record this frag. */
+ xtensa_maybe_create_literal_pool_frag (FALSE, FALSE);
frag_variant (rs_machine_dependent, 0, 0,
RELAX_LITERAL_POOL_BEGIN, NULL, 0, NULL);
xtensa_set_frag_assembly_state (frag_now);
static fragS *
get_literal_pool_location (segT seg)
{
+ struct litpool_seg *lps = litpool_seg_list.next;
+ struct litpool_frag *lpf;
+ for ( ; lps && lps->seg->id != seg->id; lps = lps->next)
+ ;
+ if (lps)
+ {
+ for (lpf = lps->frag_list.prev; lpf->fragP; lpf = lpf->prev)
+ { /* Skip "candidates" for now. */
+ if (lpf->fragP->fr_subtype == RELAX_LITERAL_POOL_BEGIN &&
+ lpf->priority == 1)
+ return lpf->fragP;
+ }
+ /* Must convert a lower-priority pool. */
+ for (lpf = lps->frag_list.prev; lpf->fragP; lpf = lpf->prev)
+ {
+ if (lpf->fragP->fr_subtype == RELAX_LITERAL_POOL_BEGIN)
+ return lpf->fragP;
+ }
+ /* Still no match -- try for a low priority pool. */
+ for (lpf = lps->frag_list.prev; lpf->fragP; lpf = lpf->prev)
+ {
+ if (lpf->fragP->fr_subtype == RELAX_LITERAL_POOL_CANDIDATE_BEGIN)
+ return lpf->fragP;
+ }
+ }
return seg_info (seg)->tc_segment_info_data.literal_pool_loc;
}
frag_now->tc_frag_data.slot_symbols[slot] = tinsn->symbol;
frag_now->tc_frag_data.slot_offsets[slot] = tinsn->offset;
frag_now->tc_frag_data.literal_frags[slot] = tinsn->literal_frag;
+ if (tinsn->opcode == xtensa_l32r_opcode)
+ {
+ frag_now->tc_frag_data.literal_frags[slot] =
+ tinsn->tok[1].X_add_symbol->sy_frag;
+ }
if (tinsn->literal_space != 0)
xg_assemble_literal_space (tinsn->literal_space, slot);
frag_now->tc_frag_data.free_reg[slot] = tinsn->extra_arg;
frag_now->fr_symbol, frag_now->fr_offset, NULL);
xtensa_set_frag_assembly_state (frag_now);
xtensa_maybe_create_trampoline_frag ();
+ /* Always create one here. */
+ xtensa_maybe_create_literal_pool_frag (TRUE, FALSE);
}
else if (is_branch && do_align_targets ())
{
clear_frag_count ();
unreachable_count = 0;
}
+
+ /* We create an area for a possible literal pool every N (default 5000)
+ frags or so. */
+ xtensa_maybe_create_literal_pool_frag (TRUE, TRUE);
}
static xtensa_insnbuf trampoline_buf = NULL;
static xtensa_insnbuf trampoline_slotbuf = NULL;
+static xtensa_insnbuf litpool_buf = NULL;
+static xtensa_insnbuf litpool_slotbuf = NULL;
+
#define TRAMPOLINE_FRAG_SIZE 3000
static void
}
}
+static void dump_litpools (void) __attribute__ ((unused));
+
+static void
+dump_litpools (void)
+{
+ struct litpool_seg *lps = litpool_seg_list.next;
+ struct litpool_frag *lpf;
+
+ for ( ; lps ; lps = lps->next )
+ {
+ printf("litpool seg %s\n", lps->seg->name);
+ for ( lpf = lps->frag_list.next; lpf->fragP; lpf = lpf->next )
+ {
+ fragS *litfrag = lpf->fragP->fr_next;
+ int count = 0;
+ while (litfrag && litfrag->fr_subtype != RELAX_LITERAL_POOL_END)
+ {
+ if (litfrag->fr_fix == 4)
+ count++;
+ litfrag = litfrag->fr_next;
+ }
+ printf(" %ld <%d:%d> (%d) [%d]: ",
+ lpf->addr, lpf->priority, lpf->original_priority,
+ lpf->fragP->fr_line, count);
+ //dump_frag(lpf->fragP);
+ }
+ }
+}
+
+static void
+xtensa_maybe_create_literal_pool_frag (bfd_boolean create,
+ bfd_boolean only_if_needed)
+{
+ struct litpool_seg *lps = litpool_seg_list.next;
+ fragS *fragP;
+ struct litpool_frag *lpf;
+ bfd_boolean needed = FALSE;
+
+ if (use_literal_section || !auto_litpools)
+ return;
+
+ for ( ; lps ; lps = lps->next )
+ {
+ if (lps->seg == now_seg)
+ break;
+ }
+
+ if (lps == NULL)
+ {
+ lps = (struct litpool_seg *)xcalloc (sizeof (struct litpool_seg), 1);
+ lps->next = litpool_seg_list.next;
+ litpool_seg_list.next = lps;
+ lps->seg = now_seg;
+ lps->frag_list.next = &lps->frag_list;
+ lps->frag_list.prev = &lps->frag_list;
+ }
+
+ lps->frag_count++;
+
+ if (create)
+ {
+ if (only_if_needed)
+ {
+ if (past_xtensa_end || !use_transform() ||
+ frag_now->tc_frag_data.is_no_transform)
+ {
+ return;
+ }
+ if (auto_litpool_limit <= 0)
+ {
+ /* Don't create a litpool based only on frag count. */
+ return;
+ }
+ else if (lps->frag_count > auto_litpool_limit)
+ {
+ needed = TRUE;
+ }
+ else
+ {
+ return;
+ }
+ }
+ else
+ {
+ needed = TRUE;
+ }
+ }
+
+ if (needed)
+ {
+ int size = (only_if_needed) ? 3 : 0; /* Space for a "j" insn. */
+ /* Create a potential site for a literal pool. */
+ frag_wane (frag_now);
+ frag_new (0);
+ xtensa_set_frag_assembly_state (frag_now);
+ fragP = frag_now;
+ fragP->tc_frag_data.lit_frchain = frchain_now;
+ fragP->tc_frag_data.literal_frag = fragP;
+ frag_var (rs_machine_dependent, size, size,
+ (only_if_needed) ?
+ RELAX_LITERAL_POOL_CANDIDATE_BEGIN :
+ RELAX_LITERAL_POOL_BEGIN,
+ NULL, 0, NULL);
+ frag_now->tc_frag_data.lit_seg = now_seg;
+ frag_variant (rs_machine_dependent, 0, 0,
+ RELAX_LITERAL_POOL_END, NULL, 0, NULL);
+ xtensa_set_frag_assembly_state (frag_now);
+ }
+ else
+ {
+ /* RELAX_LITERAL_POOL_BEGIN frag is being created;
+ just record it here. */
+ fragP = frag_now;
+ }
+
+ lpf = (struct litpool_frag *)xmalloc(sizeof (struct litpool_frag));
+ /* Insert at tail of circular list. */
+ lpf->addr = 0;
+ lps->frag_list.prev->next = lpf;
+ lpf->next = &lps->frag_list;
+ lpf->prev = lps->frag_list.prev;
+ lps->frag_list.prev = lpf;
+ lpf->fragP = fragP;
+ lpf->priority = (needed) ? (only_if_needed) ? 3 : 2 : 1;
+ lpf->original_priority = lpf->priority;
+
+ lps->frag_count = 0;
+}
+
static void
xtensa_cleanup_align_frags (void)
{
break;
case RELAX_LITERAL_POOL_BEGIN:
+ if (fragP->fr_var != 0)
+ {
+ /* We have a converted "candidate" literal pool;
+ assemble a jump around it. */
+ TInsn insn;
+ if (!litpool_slotbuf)
+ {
+ litpool_buf = xtensa_insnbuf_alloc (isa);
+ litpool_slotbuf = xtensa_insnbuf_alloc (isa);
+ }
+ new_stretch += 3;
+ fragP->tc_frag_data.relax_seen = FALSE; /* Need another pass. */
+ fragP->tc_frag_data.is_insn = TRUE;
+ tinsn_init (&insn);
+ insn.insn_type = ITYPE_INSN;
+ insn.opcode = xtensa_j_opcode;
+ insn.ntok = 1;
+ set_expr_symbol_offset (&insn.tok[0], fragP->fr_symbol,
+ fragP->fr_fix);
+ fmt = xg_get_single_format (xtensa_j_opcode);
+ tinsn_to_slotbuf (fmt, 0, &insn, litpool_slotbuf);
+ xtensa_format_set_slot (isa, fmt, 0, litpool_buf, litpool_slotbuf);
+ xtensa_insnbuf_to_chars (isa, litpool_buf,
+ (unsigned char *)fragP->fr_literal +
+ fragP->fr_fix, 3);
+ fragP->fr_fix += 3;
+ fragP->fr_var -= 3;
+ /* Add a fix-up. */
+ fix_new (fragP, 0, 3, fragP->fr_symbol, 0, TRUE,
+ BFD_RELOC_XTENSA_SLOT0_OP);
+ }
+ break;
+
case RELAX_LITERAL_POOL_END:
+ case RELAX_LITERAL_POOL_CANDIDATE_BEGIN:
case RELAX_MAYBE_UNREACHABLE:
case RELAX_MAYBE_DESIRE_ALIGN:
/* No relaxation required. */
segT dest_seg;
fixS *fix, *next_fix, **fix_splice;
sym_list *lit;
+ struct litpool_seg *lps;
mark_literal_frags (literal_head->next);
if (use_literal_section)
return;
+ /* Assign addresses (rough estimates) to the potential literal pool locations
+ and create new ones if the gaps are too large. */
+
+ for (lps = litpool_seg_list.next; lps; lps = lps->next)
+ {
+ frchainS *frchP = seg_info (lps->seg)->frchainP;
+ struct litpool_frag *lpf = lps->frag_list.next;
+ addressT addr = 0;
+
+ for ( ; frchP; frchP = frchP->frch_next)
+ {
+ fragS *fragP;
+ for (fragP = frchP->frch_root; fragP; fragP = fragP->fr_next)
+ {
+ if (lpf && fragP == lpf->fragP)
+ {
+ gas_assert(fragP->fr_type == rs_machine_dependent &&
+ (fragP->fr_subtype == RELAX_LITERAL_POOL_BEGIN ||
+ fragP->fr_subtype == RELAX_LITERAL_POOL_CANDIDATE_BEGIN));
+ /* Found a litpool location. */
+ lpf->addr = addr;
+ lpf = lpf->next;
+ }
+ if (fragP->fr_type == rs_machine_dependent &&
+ fragP->fr_subtype == RELAX_SLOTS)
+ {
+ int slot;
+ for (slot = 0; slot < MAX_SLOTS; slot++)
+ {
+ if (fragP->tc_frag_data.literal_frags[slot])
+ {
+ /* L32R; point its literal to the nearest litpool
+ preferring non-"candidate" positions to avoid
+ the jump-around. */
+ fragS *litfrag = fragP->tc_frag_data.literal_frags[slot];
+ struct litpool_frag *lp = lpf->prev;
+ if (!lp->fragP)
+ {
+ break;
+ }
+ while (lp->fragP->fr_subtype ==
+ RELAX_LITERAL_POOL_CANDIDATE_BEGIN)
+ {
+ lp = lp->prev;
+ if (lp->fragP == NULL)
+ {
+ /* End of list; have to bite the bullet.
+ Take the nearest. */
+ lp = lpf->prev;
+ break;
+ }
+ /* Does it (conservatively) reach? */
+ if (addr - lp->addr <= 128 * 1024)
+ {
+ if (lp->fragP->fr_subtype == RELAX_LITERAL_POOL_BEGIN)
+ {
+ /* Found a good one. */
+ break;
+ }
+ else if (lp->prev->fragP &&
+ addr - lp->prev->addr > 128 * 1024)
+ {
+ /* This is still a "candidate" but the next one
+ will be too far away, so revert to the nearest
+ one, convert it and add the jump around. */
+ fragS *poolbeg;
+ fragS *poolend;
+ symbolS *lsym;
+ char label[10 + 2 * sizeof (fragS *)];
+ lp = lpf->prev;
+ poolbeg = lp->fragP;
+ lp->priority = 1;
+ poolbeg->fr_subtype = RELAX_LITERAL_POOL_BEGIN;
+ poolend = poolbeg->fr_next;
+ gas_assert (poolend->fr_type == rs_machine_dependent &&
+ poolend->fr_subtype == RELAX_LITERAL_POOL_END);
+ /* Create a local symbol pointing to the
+ end of the pool. */
+ sprintf (label, ".L0_LT_%p", poolbeg);
+ lsym = (symbolS *)local_symbol_make (label, lps->seg,
+ 0, poolend);
+ poolbeg->fr_symbol = lsym;
+ /* Rest is done in xtensa_relax_frag. */
+ }
+ }
+ }
+ if (! litfrag->tc_frag_data.literal_frag)
+ {
+ /* Take earliest use of this literal to avoid
+ forward refs. */
+ litfrag->tc_frag_data.literal_frag = lp->fragP;
+ }
+ }
+ }
+ }
+ addr += fragP->fr_fix;
+ if (fragP->fr_type == rs_fill)
+ addr += fragP->fr_offset;
+ }
+ }
+ }
+
for (segment = literal_head->next; segment; segment = segment->next)
{
/* Keep the literals for .init and .fini in separate sections. */
while (search_frag != frag_now)
{
next_frag = search_frag->fr_next;
-
- /* First, move the frag out of the literal section and
- to the appropriate place. */
if (search_frag->tc_frag_data.literal_frag)
{
literal_pool = search_frag->tc_frag_data.literal_frag;
frchain_to = literal_pool->tc_frag_data.lit_frchain;
gas_assert (frchain_to);
}
+
+ if (search_frag->fr_type == rs_fill && search_frag->fr_fix == 0)
+ {
+ /* Skip empty fill frags. */
+ *frag_splice = next_frag;
+ search_frag = next_frag;
+ continue;
+ }
+
+ if (search_frag->fr_type == rs_align)
+ {
+ /* Skip alignment frags, because the pool as a whole will be
+ aligned if used, and we don't want to force alignment if the
+ pool is unused. */
+ *frag_splice = next_frag;
+ search_frag = next_frag;
+ continue;
+ }
+
+ /* First, move the frag out of the literal section and
+ to the appropriate place. */
+
+ /* Insert an aligmnent frag at start of pool. */
+ if (literal_pool->fr_next->fr_type == rs_machine_dependent &&
+ literal_pool->fr_next->fr_subtype == RELAX_LITERAL_POOL_END)
+ {
+ segT pool_seg = literal_pool->fr_next->tc_frag_data.lit_seg;
+ emit_state prev_state;
+ fragS *prev_frag;
+ fragS *align_frag;
+ xtensa_switch_section_emit_state (&prev_state, pool_seg, 0);
+ prev_frag = frag_now;
+ frag_variant (rs_fill, 0, 0, 0, NULL, 0, NULL);
+ align_frag = frag_now;
+ frag_align (2, 0, 0);
+ /* Splice it into the right place. */
+ prev_frag->fr_next = align_frag->fr_next;
+ align_frag->fr_next = literal_pool->fr_next;
+ literal_pool->fr_next = align_frag;
+ /* Insert after this one. */
+ literal_pool->tc_frag_data.literal_frag = align_frag;
+ xtensa_restore_emit_state (&prev_state);
+ }
insert_after = literal_pool->tc_frag_data.literal_frag;
dest_seg = insert_after->fr_next->tc_frag_data.lit_seg;
+ /* Skip align frag. */
+ if (insert_after->fr_next->fr_type == rs_align)
+ {
+ insert_after = insert_after->fr_next;
+ }
*frag_splice = next_frag;
search_frag->fr_next = insert_after->fr_next;
&& !recursive
&& !is_init && ! is_fini)
{
- as_bad (_("literal pool location required for text-section-literals; specify with .literal_position"));
+ if (!auto_litpools)
+ {
+ as_bad (_("literal pool location required for text-section-literals; specify with .literal_position"));
+ }
/* When we mark a literal pool location, we want to put a frag in
the literal pool that points to it. But to do that, we want to