/* tc-xtensa.c -- Assemble Xtensa instructions.
- Copyright 2003, 2004, 2005, 2006, 2007, 2008, 2009
- Free Software Foundation, Inc.
+ Copyright (C) 2003-2016 Free Software Foundation, Inc.
This file is part of GAS, the GNU Assembler.
the Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston,
MA 02110-1301, USA. */
-#include <limits.h>
#include "as.h"
+#include <limits.h>
#include "sb.h"
#include "safe-ctype.h"
#include "tc-xtensa.h"
#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 finish_vinsn (vliw_insn *);
static bfd_boolean emit_single_op (TInsn *);
static int total_frag_text_expansion (fragS *);
+static bfd_boolean use_trampolines = TRUE;
+static void xtensa_check_frag_count (void);
+static void xtensa_create_trampoline_frag (bfd_boolean);
+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. */
static void tinsn_immed_from_frag (TInsn *, fragS *, int);
static int get_num_stack_text_bytes (IStack *);
static int get_num_stack_literal_bytes (IStack *);
+static bfd_boolean tinsn_to_slotbuf (xtensa_format, int, TInsn *, xtensa_insnbuf);
/* vliw_insn functions. */
option_prefer_l32r,
option_prefer_const16,
- option_target_hardware
+ option_target_hardware,
+
+ option_trampolines,
+ option_no_trampolines,
+
+ option_auto_litpools,
+ option_no_auto_litpools,
+ option_auto_litpool_limit,
};
const char *md_shortopts = "";
{ "target-hardware", required_argument, NULL, option_target_hardware },
+ { "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 }
};
directive_state[directive_transform] = FALSE;
return 1;
+ case option_trampolines:
+ use_trampolines = TRUE;
+ return 1;
+
+ case option_no_trampolines:
+ 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\
--no-allow-flix neither allow hand-written nor generate\n\
flix bundles\n\
- --rename-section old=new Rename section 'old' to 'new'\n", stream);
+ --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\
+ --[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
md_flush_pending_output ();
- switch (end_directive)
+ switch ((int) end_directive)
{
- case (directiveE) XTENSA_UNDEFINED:
+ case XTENSA_UNDEFINED:
discard_rest_of_line ();
return;
- case directive_density:
+ case (int) directive_density:
as_warn (_(".end [no-]density is ignored"));
demand_empty_rest_of_line ();
break;
- case directive_absolute_literals:
+ case (int) directive_absolute_literals:
if (!absolute_literals_supported && !end_negated)
{
as_warn (_("Xtensa absolute literals option not supported; ignored"));
if (use_literal_section || directive_state[directive_absolute_literals])
dest_seg = now_seg;
+ /* FIXME, despite the previous comments, dest_seg is unused... */
+ (void) dest_seg;
+
/* All literals are aligned to four-byte boundaries. */
frag_align (2, 0, 0);
record_alignment (now_seg, 2);
- c = get_symbol_end ();
+ c = get_symbol_name (&base_name);
/* Just after name is now '\0'. */
p = input_line_pointer;
*p = c;
- SKIP_WHITESPACE ();
+ SKIP_WHITESPACE_AFTER_NAME ();
if (*input_line_pointer != ',' && *input_line_pointer != ':')
{
xtensa_restore_emit_state (&state);
return;
}
- *p = 0;
+ *p = 0;
colon (base_name);
-
*p = c;
+
input_line_pointer++; /* skip ',' or ':' */
xtensa_elf_cons (4);
{
struct suffix_reloc_map *sfx;
unsigned char operator = (unsigned char) -1;
-
+
for (sfx = &suffix_relocs[0]; sfx->suffix; sfx++)
{
if (sfx->reloc == reloc)
}
/* Don't do anything special with NOPs inside FLIX instructions. They
- are handled elsewhere. Real NOP instructions are always available
+ are handled elsewhere. Real NOP instructions are always available
in configurations with FLIX, so this should never be an issue but
check for it anyway. */
if (!cur_vinsn.inside_bundle && xtensa_nop_opcode == XTENSA_UNDEFINED
if (xtensa_operand_is_PCrelative (xtensa_default_isa, opcode, operand)
== 1)
as_bad_where ((char *) file, line,
- _("operand %d of '%s' has out of range value '%u'"),
+ _("operand %d of '%s' has out of range value '%u'"),
operand + 1,
xtensa_opcode_name (xtensa_default_isa, opcode),
value);
be accompanied by major changes to make use of that data.
In any event, we can tell that we are expanding from a single-slot
- three-byte format to a wider one with the logic below. */
+ format to a wider one with the logic below. */
- if (fmt_size <= 3 && fragP->tc_frag_data.text_expansion[0] != 3)
- return 3 + fragP->tc_frag_data.text_expansion[0];
- else
- return 3;
+ int i;
+ int relaxed_size = fmt_size + fragP->tc_frag_data.text_expansion[0];
+
+ for (i = 0; i < xtensa_isa_num_formats (isa); i++)
+ {
+ if (relaxed_size == xtensa_format_length (isa, i))
+ return relaxed_size;
+ }
+
+ return 3;
}
if (fragP->tc_frag_data.slot_subtypes[0] == RELAX_NARROW)
}
+/* As specified in the relaxation table, when a loop instruction is
+ relaxed, there are 24 bytes between the loop instruction itself and
+ the first instruction in the loop. */
+
+#define RELAXED_LOOP_INSN_BYTES 24
+
static addressT
next_frag_pre_opcode_bytes (const fragS *fragp)
{
been relaxed. Note that we can assume that the LOOP
instruction is in slot 0 because loops aren't bundleable. */
if (next_fragp->tc_frag_data.slot_subtypes[0] > RELAX_IMMED)
- return get_expanded_loop_offset (next_opcode);
+ return get_expanded_loop_offset (next_opcode) + RELAXED_LOOP_INSN_BYTES;
return 0;
}
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;
}
addressT frag_addr;
xtensa_format fmt;
- xtensa_insnbuf_from_chars
- (isa, insnbuf, (unsigned char *) frag->fr_literal, 0);
- fmt = xtensa_format_decode (isa, insnbuf);
- op_size = xtensa_format_length (isa, fmt);
- frag_addr = frag->fr_address % xtensa_fetch_width;
+ if (frag->fr_fix == 0)
+ frag = next_non_empty_frag (frag);
- if (frag_addr + op_size > xtensa_fetch_width)
- as_warn_where (frag->fr_file, frag->fr_line,
- _("unaligned loop: %d bytes at 0x%lx"),
- op_size, (long) frag->fr_address);
+ if (frag)
+ {
+ xtensa_insnbuf_from_chars
+ (isa, insnbuf, (unsigned char *) frag->fr_literal, 0);
+ fmt = xtensa_format_decode (isa, insnbuf);
+ op_size = xtensa_format_length (isa, fmt);
+ frag_addr = frag->fr_address % xtensa_fetch_width;
+
+ if (frag_addr + op_size > xtensa_fetch_width)
+ as_warn_where (frag->fr_file, frag->fr_line,
+ _("unaligned loop: %d bytes at 0x%lx"),
+ op_size, (long) frag->fr_address);
+ }
}
frag = frag->fr_next;
}
xtensa_rsr_lcount_opcode = xtensa_opcode_lookup (isa, "rsr.lcount");
xtensa_waiti_opcode = xtensa_opcode_lookup (isa, "waiti");
- for (i = 0; i < xtensa_isa_num_formats (isa); i++)
+ for (i = 0; i < xtensa_isa_num_formats (isa); i++)
{
int format_slots = xtensa_format_num_slots (isa, i);
if (format_slots > config_max_slots)
bfd_reloc_code_real_type reloc;
char *old_input_line_pointer;
expressionS *tok = &orig_insn.extra_arg;
- segT t;
old_input_line_pointer = input_line_pointer;
input_line_pointer = arg_strings[num_args - 1];
- t = expression (tok);
+ expression (tok);
if (tok->X_op == O_symbol
&& ((reloc = xtensa_elf_suffix (&input_line_pointer, tok))
== BFD_RELOC_XTENSA_TLS_CALL))
/* We've just emitted a new instruction so clear the list of labels. */
xtensa_clear_insn_labels ();
+
+ xtensa_check_frag_count ();
}
&& ! fragP->tc_frag_data.is_literal
&& (fragP->fr_type == rs_align
|| fragP->fr_type == rs_align_code)
- && fragP->fr_address + fragP->fr_fix > 0
&& fragP->fr_offset > 0
&& now_seg != bss_section)
{
symbolS *expr_symbols = NULL;
-void
+void
xtensa_symbol_new_hook (symbolS *sym)
{
if (is_leb128_expr && S_GET_SEGMENT (sym) == expr_section)
{
case BFD_RELOC_8:
fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF8;
+ fixP->fx_signed = 0;
break;
case BFD_RELOC_16:
fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF16;
+ fixP->fx_signed = 0;
break;
case BFD_RELOC_32:
fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF32;
+ fixP->fx_signed = 0;
break;
default:
break;
xg_assemble_vliw_tokens (vinsn);
xg_clear_vinsn (vinsn);
+
+ xtensa_check_frag_count ();
}
if (frag_now_fix () != 0
&& (! frag_now->tc_frag_data.is_insn
|| (vinsn_has_specific_opcodes (vinsn) && use_transform ())
- || !use_transform () != frag_now->tc_frag_data.is_no_transform
+ || (!use_transform ()) != frag_now->tc_frag_data.is_no_transform
|| (directive_state[directive_longcalls]
!= frag_now->tc_frag_data.use_longcalls)
|| (directive_state[directive_absolute_literals]
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;
RELAX_UNREACHABLE,
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 ())
{
xtensa_sanity_check ();
xtensa_add_config_info ();
+
+ xtensa_check_frag_count ();
+}
+
+
+struct trampoline_frag
+{
+ struct trampoline_frag *next;
+ bfd_boolean needs_jump_around;
+ fragS *fragP;
+ fixS *fixP;
+};
+
+struct trampoline_seg
+{
+ struct trampoline_seg *next;
+ asection *seg;
+ struct trampoline_frag trampoline_list;
+};
+
+static struct trampoline_seg trampoline_seg_list;
+#define J_RANGE (128 * 1024)
+
+static int unreachable_count = 0;
+
+
+static void
+xtensa_maybe_create_trampoline_frag (void)
+{
+ if (!use_trampolines)
+ return;
+
+ /* We create an area for possible trampolines every 10 unreachable frags.
+ These are preferred over the ones not preceded by an unreachable frag,
+ because we don't have to jump around them. This function is called after
+ each RELAX_UNREACHABLE frag is created. */
+
+ if (++unreachable_count > 10)
+ {
+ xtensa_create_trampoline_frag (FALSE);
+ clear_frag_count ();
+ unreachable_count = 0;
+ }
+}
+
+static void
+xtensa_check_frag_count (void)
+{
+ if (!use_trampolines || frag_now->tc_frag_data.is_no_transform)
+ return;
+
+ /* We create an area for possible trampolines every 8000 frags or so. This
+ is an estimate based on the max range of a "j" insn (+/-128K) divided
+ by a typical frag byte count (16), minus a few for safety. This function
+ is called after each source line is processed. */
+
+ if (get_frag_count () > 8000)
+ {
+ xtensa_create_trampoline_frag (TRUE);
+ 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
+xtensa_create_trampoline_frag (bfd_boolean needs_jump_around)
+{
+ /* Emit a frag where we can place intermediate jump instructions,
+ in case we need to jump farther than 128K bytes.
+ Each jump instruction takes three bytes.
+ We allocate enough for 1000 trampolines in each frag.
+ If that's not enough, oh well. */
+
+ struct trampoline_seg *ts = trampoline_seg_list.next;
+ struct trampoline_frag *tf;
+ char *varP;
+ fragS *fragP;
+ int size = TRAMPOLINE_FRAG_SIZE;
+
+ for ( ; ts; ts = ts->next)
+ {
+ if (ts->seg == now_seg)
+ break;
+ }
+
+ if (ts == NULL)
+ {
+ ts = (struct trampoline_seg *)xcalloc(sizeof (struct trampoline_seg), 1);
+ ts->next = trampoline_seg_list.next;
+ trampoline_seg_list.next = ts;
+ ts->seg = now_seg;
+ }
+
+ frag_wane (frag_now);
+ frag_new (0);
+ xtensa_set_frag_assembly_state (frag_now);
+ varP = frag_var (rs_machine_dependent, size, size, RELAX_TRAMPOLINE, NULL, 0, NULL);
+ fragP = (fragS *)(varP - SIZEOF_STRUCT_FRAG);
+ if (trampoline_buf == NULL)
+ {
+ trampoline_buf = xtensa_insnbuf_alloc (xtensa_default_isa);
+ trampoline_slotbuf = xtensa_insnbuf_alloc (xtensa_default_isa);
+ }
+ tf = (struct trampoline_frag *)xmalloc(sizeof (struct trampoline_frag));
+ tf->next = ts->trampoline_list.next;
+ ts->trampoline_list.next = tf;
+ tf->needs_jump_around = needs_jump_around;
+ tf->fragP = fragP;
+ tf->fixP = NULL;
+}
+
+
+static struct trampoline_seg *
+find_trampoline_seg (asection *seg)
+{
+ struct trampoline_seg *ts = trampoline_seg_list.next;
+
+ for ( ; ts; ts = ts->next)
+ {
+ if (ts->seg == seg)
+ return ts;
+ }
+
+ return NULL;
}
+void dump_trampolines (void);
+
+void
+dump_trampolines (void)
+{
+ struct trampoline_seg *ts = trampoline_seg_list.next;
+
+ for ( ; ts; ts = ts->next)
+ {
+ asection *seg = ts->seg;
+
+ if (seg == NULL)
+ continue;
+ fprintf(stderr, "SECTION %s\n", seg->name);
+ struct trampoline_frag *tf = ts->trampoline_list.next;
+ for ( ; tf; tf = tf->next)
+ {
+ if (tf->fragP == NULL)
+ continue;
+ fprintf(stderr, " 0x%08x: fix=%d, jump_around=%s\n",
+ (int)tf->fragP->fr_address, (int)tf->fragP->fr_fix,
+ tf->needs_jump_around ? "T" : "F");
+ }
+ }
+}
+
+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)
{
|| fragP->fr_subtype == RELAX_CHECK_ALIGN_NEXT_OPCODE))
{
/* Find the loop frag. */
- fragS *targ_frag = next_non_empty_frag (fragP);
+ fragS *loop_frag = next_non_empty_frag (fragP);
/* Find the first insn frag. */
- targ_frag = next_non_empty_frag (targ_frag);
+ fragS *targ_frag = next_non_empty_frag (loop_frag);
+
+ /* Handle a corner case that comes up in hardware
+ diagnostics. The original assembly looks like this:
+
+ loop aX, LabelA
+ <empty_frag>--not found by next_non_empty_frag
+ loop aY, LabelB
+
+ Depending on the start address, the assembler may or
+ may not change it to look something like this:
+
+ loop aX, LabelA
+ nop--frag isn't empty anymore
+ loop aY, LabelB
+
+ So set up to check the alignment of the nop if it
+ exists */
+ while (loop_frag != targ_frag)
+ {
+ if (loop_frag->fr_type == rs_machine_dependent
+ && (loop_frag->fr_subtype == RELAX_ALIGN_NEXT_OPCODE
+ || loop_frag->fr_subtype
+ == RELAX_CHECK_ALIGN_NEXT_OPCODE))
+ targ_frag = loop_frag;
+ else
+ loop_frag = loop_frag->fr_next;
+ }
/* Of course, sometimes (mostly for toy test cases) a
zero-cost loop instruction is the last in a section. */
sleb128 value, the linker is unable to adjust that value to account for
link-time relaxation. Mark all the code between such symbols so that
its size cannot be changed by linker relaxation. */
-
+
static void
xtensa_mark_difference_of_two_symbols (void)
{
symbolS *expr_sym;
- for (expr_sym = expr_symbols; expr_sym;
+ for (expr_sym = expr_symbols; expr_sym;
expr_sym = symbol_get_tc (expr_sym)->next_expr_symbol)
{
expressionS *exp = symbol_get_value_expression (expr_sym);
{
symbolS *left = exp->X_add_symbol;
symbolS *right = exp->X_op_symbol;
-
+
/* Difference of two symbols not in the same section
are handled with relocations in the linker. */
if (S_GET_SEGMENT (left) == S_GET_SEGMENT (right))
fragS *end;
fragS *walk;
- if (symbol_get_frag (left)->fr_address
+ if (symbol_get_frag (left)->fr_address
<= symbol_get_frag (right)->fr_address)
{
start = symbol_get_frag (left);
walk = start->tc_frag_data.no_transform_end;
else
walk = start;
- do
+ do
{
walk->tc_frag_data.is_no_transform = 1;
walk = walk->fr_next;
for (frchP = seg_info (s)->frchainP; frchP; frchP = frchP->frch_next)
{
fragS *fragP;
- fragS *current_target = NULL;
xtensa_opcode current_opcode = XTENSA_UNDEFINED;
/* Walk over all of the fragments in a subsection. */
TInsn t_insn;
fragS *loop_frag = next_non_empty_frag (fragP);
tinsn_from_chars (&t_insn, loop_frag->fr_opcode, 0);
- current_target = symbol_get_frag (fragP->fr_symbol);
current_opcode = t_insn.opcode;
gas_assert (xtensa_opcode_is_loop (xtensa_default_isa,
current_opcode) == 1);
for (fragP = frchP->frch_root; fragP; fragP = fragP->fr_next)
{
if (fragP->fr_type == rs_machine_dependent
- && fragP->fr_subtype == RELAX_SLOTS
+ && fragP->fr_subtype == RELAX_SLOTS
&& fragP->tc_frag_data.slot_subtypes[0] == RELAX_IMMED)
{
static xtensa_insnbuf insnbuf = NULL;
{
if (target_size <= 4)
return 2;
- gas_assert (target_size == 8);
- return 3;
+
+ if (target_size <= 8)
+ return 3;
+
+ if (target_size <= 16)
+ return 4;
+
+ if (target_size <= 32)
+ return 5;
+
+ if (target_size <= 64)
+ return 6;
+
+ if (target_size <= 128)
+ return 7;
+
+ if (target_size <= 256)
+ return 8;
+
+ if (target_size <= 512)
+ return 9;
+
+ if (target_size <= 1024)
+ return 10;
+
+ gas_assert (0);
+ return 0;
}
static int
branch_align_power (segT sec)
{
- /* If the Xtensa processor has a fetch width of 8 bytes, and the section
- is aligned to at least an 8-byte boundary, then a branch target need
- only fit within an 8-byte aligned block of memory to avoid a stall.
- Otherwise, try to fit branch targets within 4-byte aligned blocks
- (which may be insufficient, e.g., if the section has no alignment, but
- it's good enough). */
- if (xtensa_fetch_width == 8)
- {
- if (get_recorded_alignment (sec) >= 3)
- return 3;
- }
- else
- gas_assert (xtensa_fetch_width == 4);
+ /* If the Xtensa processor has a fetch width of X, and
+ the section is aligned to at least that boundary, then a branch
+ target need only fit within that aligned block of memory to avoid
+ a stall. Otherwise, try to fit branch targets within 4-byte
+ aligned blocks (which may be insufficient, e.g., if the section
+ has no alignment, but it's good enough). */
+ int fetch_align = get_text_align_power(xtensa_fetch_width);
+ int sec_align = get_recorded_alignment (sec);
+
+ if (sec_align >= fetch_align)
+ return fetch_align;
return 2;
}
static long relax_frag_immed
(segT, fragS *, long, int, xtensa_format, int, int *, bfd_boolean);
+typedef struct cached_fixup cached_fixupS;
+struct cached_fixup
+{
+ int addr;
+ int target;
+ int delta;
+ fixS *fixP;
+};
+
+typedef struct fixup_cache fixup_cacheS;
+struct fixup_cache
+{
+ cached_fixupS *fixups;
+ unsigned n_fixups;
+ unsigned n_max;
+
+ segT seg;
+ fragS *first_frag;
+};
+
+static int fixup_order (const void *a, const void *b)
+{
+ const cached_fixupS *pa = a;
+ const cached_fixupS *pb = b;
+
+ if (pa->addr == pb->addr)
+ {
+ if (pa->target == pb->target)
+ {
+ if (pa->fixP->fx_r_type == pb->fixP->fx_r_type)
+ return 0;
+ return pa->fixP->fx_r_type < pb->fixP->fx_r_type ? -1 : 1;
+ }
+ return pa->target - pb->target;
+ }
+ return pa->addr - pb->addr;
+}
+
+static bfd_boolean xtensa_make_cached_fixup (cached_fixupS *o, fixS *fixP)
+{
+ xtensa_isa isa = xtensa_default_isa;
+ int addr = fixP->fx_frag->fr_address;
+ int target;
+ int delta;
+ symbolS *s = fixP->fx_addsy;
+ int slot;
+ xtensa_format fmt;
+ xtensa_opcode opcode;
+
+ if (fixP->fx_r_type < BFD_RELOC_XTENSA_SLOT0_OP ||
+ fixP->fx_r_type > BFD_RELOC_XTENSA_SLOT14_OP)
+ return FALSE;
+ target = S_GET_VALUE (s);
+ delta = target - addr;
+
+ if (abs(delta) < J_RANGE / 2)
+ return FALSE;
+
+ xtensa_insnbuf_from_chars (isa, trampoline_buf,
+ (unsigned char *) fixP->fx_frag->fr_literal +
+ fixP->fx_where, 0);
+ fmt = xtensa_format_decode (isa, trampoline_buf);
+ gas_assert (fmt != XTENSA_UNDEFINED);
+ slot = fixP->tc_fix_data.slot;
+ xtensa_format_get_slot (isa, fmt, slot, trampoline_buf, trampoline_slotbuf);
+ opcode = xtensa_opcode_decode (isa, fmt, slot, trampoline_slotbuf);
+ if (opcode != xtensa_j_opcode)
+ return FALSE;
+
+ o->addr = addr;
+ o->target = target;
+ o->delta = delta;
+ o->fixP = fixP;
+
+ return TRUE;
+}
+
+static void xtensa_realloc_fixup_cache (fixup_cacheS *cache, unsigned add)
+{
+ if (cache->n_fixups + add > cache->n_max)
+ {
+ cache->n_max = (cache->n_fixups + add) * 2;
+ cache->fixups = xrealloc (cache->fixups,
+ sizeof (*cache->fixups) * cache->n_max);
+ }
+}
+
+static void xtensa_cache_relaxable_fixups (fixup_cacheS *cache,
+ segment_info_type *seginfo)
+{
+ fixS *fixP;
+
+ cache->n_fixups = 0;
+
+ for (fixP = seginfo->fix_root; fixP ; fixP = fixP->fx_next)
+ {
+ xtensa_realloc_fixup_cache (cache, 1);
+
+ if (xtensa_make_cached_fixup (cache->fixups + cache->n_fixups, fixP))
+ ++cache->n_fixups;
+ }
+ qsort (cache->fixups, cache->n_fixups, sizeof (*cache->fixups), fixup_order);
+}
+
+static unsigned xtensa_find_first_cached_fixup (const fixup_cacheS *cache,
+ int addr)
+{
+ unsigned a = 0;
+ unsigned b = cache->n_fixups;
+
+ while (b - a > 1)
+ {
+ unsigned c = (a + b) / 2;
+
+ if (cache->fixups[c].addr < addr)
+ a = c;
+ else
+ b = c;
+ }
+ return a;
+}
+
+static void xtensa_delete_cached_fixup (fixup_cacheS *cache, unsigned i)
+{
+ memmove (cache->fixups + i, cache->fixups + i + 1,
+ (cache->n_fixups - i - 1) * sizeof (*cache->fixups));
+ --cache->n_fixups;
+}
+
+static bfd_boolean xtensa_add_cached_fixup (fixup_cacheS *cache, fixS *fixP)
+{
+ cached_fixupS o;
+ unsigned i;
+
+ if (!xtensa_make_cached_fixup (&o, fixP))
+ return FALSE;
+ xtensa_realloc_fixup_cache (cache, 1);
+ i = xtensa_find_first_cached_fixup (cache, o.addr);
+ if (i < cache->n_fixups)
+ {
+ ++i;
+ memmove (cache->fixups + i + 1, cache->fixups + i,
+ (cache->n_fixups - i) * sizeof (*cache->fixups));
+ }
+ cache->fixups[i] = o;
+ ++cache->n_fixups;
+ return TRUE;
+}
/* Return the number of bytes added to this fragment, given that the
input has been stretched already by "stretch". */
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. */
new_stretch += relax_frag_for_align (fragP, stretch);
break;
+ case RELAX_TRAMPOLINE:
+ if (fragP->tc_frag_data.relax_seen)
+ {
+ static fixup_cacheS fixup_cache;
+ segment_info_type *seginfo = seg_info (now_seg);
+ int trampaddr = fragP->fr_address + fragP->fr_fix;
+ int searchaddr = trampaddr < J_RANGE ? 0 : trampaddr - J_RANGE;
+ unsigned i;
+
+ if (now_seg != fixup_cache.seg ||
+ fragP == fixup_cache.first_frag ||
+ fixup_cache.first_frag == NULL)
+ {
+ xtensa_cache_relaxable_fixups (&fixup_cache, seginfo);
+ fixup_cache.seg = now_seg;
+ fixup_cache.first_frag = fragP;
+ }
+
+ /* Scan for jumps that will not reach. */
+ for (i = xtensa_find_first_cached_fixup (&fixup_cache, searchaddr);
+ i < fixup_cache.n_fixups; ++i)
+
+ {
+ fixS *fixP = fixup_cache.fixups[i].fixP;
+ int target = fixup_cache.fixups[i].target;
+ int addr = fixup_cache.fixups[i].addr;
+ int delta = fixup_cache.fixups[i].delta + stretch;
+
+ trampaddr = fragP->fr_address + fragP->fr_fix;
+
+ if (addr + J_RANGE < trampaddr)
+ continue;
+ if (addr > trampaddr + J_RANGE)
+ break;
+ if (abs (delta) < J_RANGE)
+ continue;
+
+ slot = fixP->tc_fix_data.slot;
+
+ if (delta > J_RANGE || delta < -1 * J_RANGE)
+ { /* Found an out-of-range jump; scan the list of trampolines for the best match. */
+ struct trampoline_seg *ts = find_trampoline_seg (now_seg);
+ struct trampoline_frag *tf = ts->trampoline_list.next;
+ struct trampoline_frag *prev = &ts->trampoline_list;
+ int lower = (target < addr) ? target : addr;
+ int upper = (target > addr) ? target : addr;
+ int midpoint = lower + (upper - lower) / 2;
+
+ if ((upper - lower) > 2 * J_RANGE)
+ {
+ /* One trampoline won't suffice; we need multiple jumps.
+ Jump to the trampoline that's farthest, but still in
+ range relative to the original "j" instruction. */
+ for ( ; tf; prev = tf, tf = tf->next )
+ {
+ int this_addr = tf->fragP->fr_address + tf->fragP->fr_fix;
+ int next_addr = (tf->next) ? tf->next->fragP->fr_address + tf->next->fragP->fr_fix : 0 ;
+
+ if (addr == lower)
+ {
+ /* Forward jump. */
+ if (this_addr - addr < J_RANGE)
+ break;
+ }
+ else
+ {
+ /* Backward jump. */
+ if (next_addr == 0 || addr - next_addr > J_RANGE)
+ break;
+ }
+ }
+ }
+ else
+ {
+ struct trampoline_frag *best_tf = NULL;
+ int best_delta = 0;
+
+ for ( ; tf; prev = tf, tf = tf->next )
+ {
+ int this_addr = tf->fragP->fr_address + tf->fragP->fr_fix;
+ int this_delta = abs (this_addr - midpoint);
+
+ if (!best_tf || this_delta < best_delta)
+ {
+ best_tf = tf;
+ best_delta = this_delta;
+ }
+ }
+ tf = best_tf;
+ }
+ if (tf->fragP == fragP)
+ {
+ if (abs (addr - trampaddr) < J_RANGE)
+ { /* The trampoline is in range of original; fix it! */
+ fixS *newfixP;
+ int offset;
+ TInsn insn;
+ symbolS *lsym;
+ fragS *fP; /* The out-of-range jump. */
+
+ new_stretch += init_trampoline_frag (tf);
+ offset = fragP->fr_fix; /* Where to assemble the j insn. */
+ lsym = fragP->fr_symbol;
+ fP = fixP->fx_frag;
+ /* Assemble a jump to the target label here. */
+ tinsn_init (&insn);
+ insn.insn_type = ITYPE_INSN;
+ insn.opcode = xtensa_j_opcode;
+ insn.ntok = 1;
+ set_expr_symbol_offset (&insn.tok[0], lsym, offset);
+ fmt = xg_get_single_format (xtensa_j_opcode);
+ tinsn_to_slotbuf (fmt, 0, &insn, trampoline_slotbuf);
+ xtensa_format_set_slot (isa, fmt, 0, trampoline_buf, trampoline_slotbuf);
+ xtensa_insnbuf_to_chars (isa, trampoline_buf, (unsigned char *)fragP->fr_literal + offset, 3);
+ fragP->fr_fix += 3;
+ fragP->fr_var -= 3;
+ /* Add a fix-up for the original j insn. */
+ newfixP = fix_new (fP, fixP->fx_where, fixP->fx_size, lsym, fragP->fr_fix - 3, TRUE, fixP->fx_r_type);
+ newfixP->fx_no_overflow = 1;
+ newfixP->tc_fix_data.X_add_symbol = lsym;
+ newfixP->tc_fix_data.X_add_number = offset;
+ newfixP->tc_fix_data.slot = slot;
+
+ xtensa_delete_cached_fixup (&fixup_cache, i);
+ xtensa_add_cached_fixup (&fixup_cache, newfixP);
+
+ /* Move the fix-up from the original j insn to this one. */
+ fixP->fx_frag = fragP;
+ fixP->fx_where = fragP->fr_fix - 3;
+ fixP->tc_fix_data.slot = 0;
+
+ xtensa_add_cached_fixup (&fixup_cache, fixP);
+
+ /* re-do current fixup */
+ --i;
+
+ /* Adjust the jump around this trampoline (if present). */
+ if (tf->fixP != NULL)
+ {
+ tf->fixP->fx_offset += 3;
+ }
+ new_stretch += 3;
+ fragP->tc_frag_data.relax_seen = FALSE; /* Need another pass. */
+ /* Do we have room for more? */
+ if (fragP->fr_var < 3)
+ { /* No, convert to fill. */
+ frag_wane (fragP);
+ fragP->fr_subtype = 0;
+ /* Remove from the trampoline_list. */
+ prev->next = tf->next;
+ if (fragP == fixup_cache.first_frag)
+ fixup_cache.first_frag = NULL;
+ break;
+ }
+ }
+ }
+ }
+ }
+ }
+ break;
+
default:
as_bad (_("bad relaxation state"));
}
(*widens)++;
break;
}
- address += total_frag_text_expansion (fragP);;
+ address += total_frag_text_expansion (fragP);
break;
case RELAX_IMMED:
/* The idea: widen everything you can to get a target or loop aligned,
then start using NOPs.
- When we must have a NOP, here is a table of how we decide
- (so you don't have to fight through the control flow below):
-
wide_nops = the number of wide NOPs available for aligning
narrow_nops = the number of narrow NOPs available for aligning
(a subset of wide_nops)
widens = the number of narrow instructions that should be widened
- Desired wide narrow
- Diff nop nop widens
- 1 0 0 1
- 2 0 1 0
- 3a 1 0 0
- b 0 1 1 (case 3a makes this case unnecessary)
- 4a 1 0 1
- b 0 2 0
- c 0 1 2 (case 4a makes this case unnecessary)
- 5a 1 0 2
- b 1 1 0
- c 0 2 1 (case 5b makes this case unnecessary)
- 6a 2 0 0
- b 1 0 3
- c 0 1 4 (case 6b makes this case unnecessary)
- d 1 1 1 (case 6a makes this case unnecessary)
- e 0 2 2 (case 6a makes this case unnecessary)
- f 0 3 0 (case 6a makes this case unnecessary)
- 7a 1 0 4
- b 2 0 1
- c 1 1 2 (case 7b makes this case unnecessary)
- d 0 1 5 (case 7a makes this case unnecessary)
- e 0 2 3 (case 7b makes this case unnecessary)
- f 0 3 1 (case 7b makes this case unnecessary)
- g 1 2 1 (case 7b makes this case unnecessary)
*/
static long
int num_widens,
int desired_diff)
{
+ int nops_needed;
+ int nop_bytes;
+ int extra_bytes;
int bytes_short = desired_diff - num_widens;
- gas_assert (desired_diff >= 0
+ gas_assert (desired_diff >= 0
&& desired_diff < (signed) xtensa_fetch_width);
if (desired_diff == 0)
return 0;
/* From here we will need at least one NOP to get an alignment.
However, we may not be able to align at all, in which case,
don't widen. */
- if (this_frag->fr_subtype == RELAX_FILL_NOP)
+ nops_needed = desired_diff / 3;
+
+ /* If there aren't enough nops, don't widen. */
+ if (nops_needed > wide_nops)
+ return 0;
+
+ /* First try it with all wide nops. */
+ nop_bytes = nops_needed * 3;
+ extra_bytes = desired_diff - nop_bytes;
+
+ if (nop_bytes + num_widens >= desired_diff)
+ {
+ if (this_frag->fr_subtype == RELAX_FILL_NOP)
+ return 3;
+ else if (num_widens == extra_bytes)
+ return 1;
+ return 0;
+ }
+
+ /* Add a narrow nop. */
+ nops_needed++;
+ nop_bytes += 2;
+ extra_bytes -= 2;
+ if (narrow_nops == 0 || nops_needed > wide_nops)
+ return 0;
+
+ if (nop_bytes + num_widens >= desired_diff && extra_bytes >= 0)
+ {
+ if (this_frag->fr_subtype == RELAX_FILL_NOP)
+ return !this_frag->tc_frag_data.is_no_density ? 2 : 3;
+ else if (num_widens == extra_bytes)
+ return 1;
+ return 0;
+ }
+
+ /* Replace a wide nop with a narrow nop--we can get here if
+ extra_bytes was negative in the previous conditional. */
+ if (narrow_nops == 1)
+ return 0;
+ nop_bytes--;
+ extra_bytes++;
+ if (nop_bytes + num_widens >= desired_diff)
{
- switch (desired_diff)
+ if (this_frag->fr_subtype == RELAX_FILL_NOP)
+ return !this_frag->tc_frag_data.is_no_density ? 2 : 3;
+ else if (num_widens == extra_bytes)
+ return 1;
+ return 0;
+ }
+
+ /* If we can't satisfy any of the above cases, then we can't align
+ using padding or fill nops. */
+ return 0;
+}
+
+
+static struct trampoline_frag *
+search_trampolines (TInsn *tinsn, fragS *fragP, bfd_boolean unreachable_only)
+{
+ struct trampoline_seg *ts = find_trampoline_seg (now_seg);
+ struct trampoline_frag *tf = (ts) ? ts->trampoline_list.next : NULL;
+ struct trampoline_frag *best_tf = NULL;
+ int best_delta = 0;
+ int best_addr = 0;
+ symbolS *sym = tinsn->tok[0].X_add_symbol;
+ offsetT target = S_GET_VALUE (sym) + tinsn->tok[0].X_add_number;
+ offsetT addr = fragP->fr_address;
+ offsetT lower = (addr < target) ? addr : target;
+ offsetT upper = (addr > target) ? addr : target;
+ int delta = upper - lower;
+ offsetT midpoint = lower + delta / 2;
+ int this_delta = -1;
+ int this_addr = -1;
+
+ if (delta > 2 * J_RANGE)
+ {
+ /* One trampoline won't do; we need multiple.
+ Choose the farthest trampoline that's still in range of the original
+ and let a later pass finish the job. */
+ for ( ; tf; tf = tf->next)
{
- case 1:
- return 0;
- case 2:
- if (!this_frag->tc_frag_data.is_no_density && narrow_nops == 1)
- return 2; /* case 2 */
- return 0;
- case 3:
- if (wide_nops > 1)
- return 0;
- else
- return 3; /* case 3a */
- case 4:
- if (num_widens >= 1 && wide_nops == 1)
- return 3; /* case 4a */
- if (!this_frag->tc_frag_data.is_no_density && narrow_nops == 2)
- return 2; /* case 4b */
- return 0;
- case 5:
- if (num_widens >= 2 && wide_nops == 1)
- return 3; /* case 5a */
- /* We will need two nops. Are there enough nops
- between here and the align target? */
- if (wide_nops < 2 || narrow_nops == 0)
- return 0;
- /* Are there other nops closer that can serve instead? */
- if (wide_nops > 2 && narrow_nops > 1)
- return 0;
- /* Take the density one first, because there might not be
- another density one available. */
- if (!this_frag->tc_frag_data.is_no_density)
- return 2; /* case 5b narrow */
+ int next_addr = (tf->next) ? tf->next->fragP->fr_address + tf->next->fragP->fr_fix : 0;
+
+ this_addr = tf->fragP->fr_address + tf->fragP->fr_fix;
+ if (lower == addr)
+ {
+ /* Forward jump. */
+ if (this_addr - addr < J_RANGE)
+ break;
+ }
else
- return 3; /* case 5b wide */
- return 0;
- case 6:
- if (wide_nops == 2)
- return 3; /* case 6a */
- else if (num_widens >= 3 && wide_nops == 1)
- return 3; /* case 6b */
- return 0;
- case 7:
- if (wide_nops == 1 && num_widens >= 4)
- return 3; /* case 7a */
- else if (wide_nops == 2 && num_widens >= 1)
- return 3; /* case 7b */
- return 0;
- default:
- gas_assert (0);
+ {
+ /* Backward jump. */
+ if (next_addr == 0 || addr - next_addr > J_RANGE)
+ break;
+ }
}
+ if (abs (addr - this_addr) < J_RANGE)
+ return tf;
+
+ return NULL;
}
- else
+ for ( ; tf; tf = tf->next)
{
- /* We will need a NOP no matter what, but should we widen
- this instruction to help?
+ this_addr = tf->fragP->fr_address + tf->fragP->fr_fix;
+ this_delta = abs (this_addr - midpoint);
+ if (unreachable_only && tf->needs_jump_around)
+ continue;
+ if (!best_tf || this_delta < best_delta)
+ {
+ best_tf = tf;
+ best_delta = this_delta;
+ best_addr = this_addr;
+ }
+ }
+
+ if (best_tf &&
+ best_delta < J_RANGE &&
+ abs(best_addr - lower) < J_RANGE &&
+ abs(best_addr - upper) < J_RANGE)
+ return best_tf;
+
+ return NULL; /* No suitable trampoline found. */
+}
- This is a RELAX_NARROW frag. */
- switch (desired_diff)
+
+static struct trampoline_frag *
+get_best_trampoline (TInsn *tinsn, fragS *fragP)
+{
+ struct trampoline_frag *tf = NULL;
+
+ tf = search_trampolines (tinsn, fragP, TRUE); /* Try unreachable first. */
+
+ if (tf == NULL)
+ tf = search_trampolines (tinsn, fragP, FALSE); /* Try ones needing a jump-around, too. */
+
+ return tf;
+}
+
+
+static void
+check_and_update_trampolines (void)
+{
+ struct trampoline_seg *ts = find_trampoline_seg (now_seg);
+ struct trampoline_frag *tf = ts->trampoline_list.next;
+ struct trampoline_frag *prev = &ts->trampoline_list;
+
+ for ( ; tf; prev = tf, tf = tf->next)
+ {
+ if (tf->fragP->fr_var < 3)
{
- case 1:
- gas_assert (0);
- return 0;
- case 2:
- case 3:
- return 0;
- case 4:
- if (wide_nops >= 1 && num_widens == 1)
- return 1; /* case 4a */
- return 0;
- case 5:
- if (wide_nops >= 1 && num_widens == 2)
- return 1; /* case 5a */
- return 0;
- case 6:
- if (wide_nops >= 2)
- return 0; /* case 6a */
- else if (wide_nops >= 1 && num_widens == 3)
- return 1; /* case 6b */
- return 0;
- case 7:
- if (wide_nops >= 1 && num_widens == 4)
- return 1; /* case 7a */
- else if (wide_nops >= 2 && num_widens == 1)
- return 1; /* case 7b */
- return 0;
- default:
- gas_assert (0);
- return 0;
+ frag_wane (tf->fragP);
+ prev->next = tf->next;
+ tf->fragP = NULL;
}
}
- gas_assert (0);
- return 0;
+}
+
+
+static int
+init_trampoline_frag (struct trampoline_frag *trampP)
+{
+ fragS *fp = trampP->fragP;
+ int growth = 0;
+
+ if (fp->fr_fix == 0)
+ {
+ symbolS *lsym;
+ char label[10 + 2 * sizeof(fp)];
+ sprintf (label, ".L0_TR_%p", fp);
+
+ lsym = (symbolS *)local_symbol_make (label, now_seg, 0, fp);
+ fp->fr_symbol = lsym;
+ if (trampP->needs_jump_around)
+ {
+ /* Add a jump around this block of jumps, in case
+ control flows into this block. */
+ fixS *fixP;
+ TInsn insn;
+ xtensa_format fmt;
+ xtensa_isa isa = xtensa_default_isa;
+
+ fp->tc_frag_data.is_insn = 1;
+ /* Assemble a jump insn. */
+ tinsn_init (&insn);
+ insn.insn_type = ITYPE_INSN;
+ insn.opcode = xtensa_j_opcode;
+ insn.ntok = 1;
+ set_expr_symbol_offset (&insn.tok[0], lsym, 3);
+ fmt = xg_get_single_format (xtensa_j_opcode);
+ tinsn_to_slotbuf (fmt, 0, &insn, trampoline_slotbuf);
+ xtensa_format_set_slot (isa, fmt, 0, trampoline_buf, trampoline_slotbuf);
+ xtensa_insnbuf_to_chars (isa, trampoline_buf, (unsigned char *)fp->fr_literal, 3);
+ fp->fr_fix += 3;
+ fp->fr_var -= 3;
+ growth = 3;
+ fixP = fix_new (fp, 0, 3, lsym, 3, TRUE, BFD_RELOC_XTENSA_SLOT0_OP);
+ trampP->fixP = fixP;
+ }
+ }
+ return growth;
+}
+
+
+static int
+add_jump_to_trampoline (struct trampoline_frag *trampP, fragS *origfrag)
+{
+ fragS *tramp = trampP->fragP;
+ fixS *fixP;
+ int offset = tramp->fr_fix; /* Where to assemble the j insn. */
+ TInsn insn;
+ symbolS *lsym;
+ symbolS *tsym;
+ int toffset;
+ xtensa_format fmt;
+ xtensa_isa isa = xtensa_default_isa;
+ int growth = 0;
+
+ lsym = tramp->fr_symbol;
+ /* Assemble a jump to the target label in the trampoline frag. */
+ tsym = origfrag->tc_frag_data.slot_symbols[0];
+ toffset = origfrag-> tc_frag_data.slot_offsets[0];
+ tinsn_init (&insn);
+ insn.insn_type = ITYPE_INSN;
+ insn.opcode = xtensa_j_opcode;
+ insn.ntok = 1;
+ set_expr_symbol_offset (&insn.tok[0], tsym, toffset);
+ fmt = xg_get_single_format (xtensa_j_opcode);
+ tinsn_to_slotbuf (fmt, 0, &insn, trampoline_slotbuf);
+ xtensa_format_set_slot (isa, fmt, 0, trampoline_buf, trampoline_slotbuf);
+ xtensa_insnbuf_to_chars (isa, trampoline_buf, (unsigned char *)tramp->fr_literal + offset, 3);
+ tramp->fr_fix += 3;
+ tramp->fr_var -= 3;
+ growth = 3;
+ /* add a fix-up for the trampoline jump. */
+ fixP = fix_new (tramp, tramp->fr_fix - 3, 3, tsym, toffset, TRUE, BFD_RELOC_XTENSA_SLOT0_OP);
+ /* Modify the jump at the start of this trampoline to point past the newly-added jump. */
+ fixP = trampP->fixP;
+ if (fixP)
+ fixP->fx_offset += 3;
+ /* Modify the original j to point here. */
+ origfrag->tc_frag_data.slot_symbols[0] = lsym;
+ origfrag->tc_frag_data.slot_offsets[0] = tramp->fr_fix - 3;
+ /* If trampoline is full, remove it from the list. */
+ check_and_update_trampolines ();
+
+ return growth;
}
/* The first instruction in the relaxed sequence will go after
the current wide instruction, and thus its symbolic immediates
might not fit. */
-
+
istack_init (&istack);
- num_steps = xg_assembly_relax (&istack, &tinsn, segP, fragP,
+ num_steps = xg_assembly_relax (&istack, &tinsn, segP, fragP,
frag_offset + old_size,
min_steps, stretch + old_size);
gas_assert (num_steps >= min_steps && num_steps <= RELAX_IMMED_MAXSTEPS);
- fragP->tc_frag_data.slot_subtypes[slot]
+ fragP->tc_frag_data.slot_subtypes[slot]
= (int) RELAX_IMMED + num_steps;
num_literal_bytes = get_num_stack_literal_bytes (&istack);
- literal_diff
+ literal_diff
= num_literal_bytes - fragP->tc_frag_data.literal_expansion[slot];
-
+
num_text_bytes = get_num_stack_text_bytes (&istack) + old_size;
}
}
if (negatable_branch && istack.ninsn > 1)
update_next_frag_state (fragP);
+ /* If last insn is a jump, and it cannot reach its target, try to find a trampoline. */
+ if (istack.ninsn > 2 &&
+ istack.insn[istack.ninsn - 1].insn_type == ITYPE_LABEL &&
+ istack.insn[istack.ninsn - 2].insn_type == ITYPE_INSN &&
+ istack.insn[istack.ninsn - 2].opcode == xtensa_j_opcode)
+ {
+ TInsn *jinsn = &istack.insn[istack.ninsn - 2];
+
+ if (!xg_symbolic_immeds_fit (jinsn, segP, fragP, fragP->fr_offset, total_text_diff))
+ {
+ struct trampoline_frag *tf = get_best_trampoline (jinsn, fragP);
+
+ if (tf)
+ {
+ this_text_diff += init_trampoline_frag (tf);
+ this_text_diff += add_jump_to_trampoline (tf, fragP);
+ }
+ else
+ {
+ /* If target symbol is undefined, assume it will reach once linked. */
+ expressionS *exp = &istack.insn[istack.ninsn - 2].tok[0];
+
+ if (exp->X_op == O_symbol && S_IS_DEFINED (exp->X_add_symbol))
+ {
+ as_bad_where (fragP->fr_file, fragP->fr_line,
+ _("jump target out of range; no usable trampoline found"));
+ }
+ }
+ }
+ }
+
return this_text_diff;
}
else
as_bad (_("invalid relaxation fragment result"));
break;
+
+ case RELAX_TRAMPOLINE:
+ break;
}
fragp->fr_var = 0;
symbolS *gen_label = NULL;
offsetT frag_offset;
bfd_boolean first = TRUE;
- bfd_boolean last_is_jump;
/* It does not fit. Find something that does and
convert immediately. */
total_size = 0;
first = TRUE;
- last_is_jump = FALSE;
for (i = 0; i < istack.ninsn; i++)
{
TInsn *tinsn = &istack.insn[i];
{
seg_list *segment;
frchainS *frchain_from, *frchain_to;
- fragS *search_frag, *next_frag, *last_frag, *literal_pool, *insert_after;
+ fragS *search_frag, *next_frag, *literal_pool, *insert_after;
fragS **frag_splice;
emit_state state;
segT dest_seg;
fixS *fix, *next_fix, **fix_splice;
sym_list *lit;
+ struct litpool_seg *lps;
+ const char *init_name = INIT_SECTION_NAME;
+ const char *fini_name = FINI_SECTION_NAME;
+ int init_name_len = strlen(init_name);
+ int fini_name_len = strlen(fini_name);
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)
{
+ const char *seg_name = segment_name (segment->seg);
+
/* Keep the literals for .init and .fini in separate sections. */
- if (!strcmp (segment_name (segment->seg), INIT_SECTION_NAME)
- || !strcmp (segment_name (segment->seg), FINI_SECTION_NAME))
+ if ((!memcmp (seg_name, init_name, init_name_len) &&
+ !strcmp (seg_name + init_name_len, ".literal")) ||
+ (!memcmp (seg_name, fini_name, fini_name_len) &&
+ !strcmp (seg_name + fini_name_len, ".literal")))
continue;
frchain_from = seg_info (segment->seg)->frchainP;
frchain_to = NULL;
frag_splice = &(frchain_from->frch_root);
- while (!search_frag->tc_frag_data.literal_frag)
+ while (search_frag && !search_frag->tc_frag_data.literal_frag)
{
gas_assert (search_frag->fr_fix == 0
|| search_frag->fr_type == rs_align);
search_frag = search_frag->fr_next;
}
+ if (!search_frag)
+ {
+ search_frag = frchain_from->frch_root;
+ as_bad_where (search_frag->fr_file, search_frag->fr_line,
+ _("literal pool location required for text-section-literals; specify with .literal_position"));
+ continue;
+ }
+
gas_assert (search_frag->tc_frag_data.literal_frag->fr_subtype
== RELAX_LITERAL_POOL_BEGIN);
xtensa_switch_section_emit_state (&state, segment->seg, 0);
frags in it. */
frag_variant (rs_fill, 0, 0, 0, NULL, 0, NULL);
xtensa_set_frag_assembly_state (frag_now);
- last_frag = frag_now;
frag_variant (rs_fill, 0, 0, 0, NULL, 0, NULL);
xtensa_set_frag_assembly_state (frag_now);
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
{
const char *gname = inf;
const char *group_name = elf_group_name (sec);
-
+
return (group_name == gname
|| (group_name != NULL
&& gname != NULL
if (*pcached)
return *pcached;
-
+
text_name = default_lit_sections.lit_prefix;
if (! text_name || ! *text_name)
{
}
else
{
- /* If the section name ends with ".text", then replace that suffix
- instead of appending an additional suffix. */
+ /* If the section name begins or ends with ".text", then replace
+ that portion instead of appending an additional suffix. */
size_t len = strlen (text_name);
- if (len >= 5 && strcmp (text_name + len - 5, ".text") == 0)
+ if (len >= 5
+ && (strcmp (text_name + len - 5, ".text") == 0
+ || strncmp (text_name, ".text", 5) == 0))
len -= 5;
name = xmalloc (len + strlen (base_name) + 1);
- strcpy (name, text_name);
- strcpy (name + len, base_name);
+ if (strncmp (text_name, ".text", 5) == 0)
+ {
+ strcpy (name, base_name);
+ strcat (name, text_name + 5);
+ }
+ else
+ {
+ strcpy (name, text_name);
+ strcpy (name + len, base_name);
+ }
}
/* Canonicalize section names to allow renaming literal sections.
void
istack_init (IStack *stack)
{
- memset (stack, 0, sizeof (IStack));
stack->ninsn = 0;
}
{
int i;
- memset (v, 0, offsetof (vliw_insn, slots)
+ memset (v, 0, offsetof (vliw_insn, slots)
+ sizeof(TInsn) * config_max_slots);
v->format = XTENSA_UNDEFINED;
static void
xg_copy_vinsn (vliw_insn *dst, vliw_insn *src)
{
- memcpy (dst, src,
+ memcpy (dst, src,
offsetof(vliw_insn, slots) + src->num_slots * sizeof(TInsn));
dst->insnbuf = src->insnbuf;
memcpy (dst->slotbuf, src->slotbuf, src->num_slots * sizeof(xtensa_insnbuf));