static int label_tick;
-/* Reset to label_tick for each label. */
+/* Reset to label_tick for each extended basic block in scanning order. */
static int label_tick_ebb_start;
if (INSN_P (insn))
free_INSN_LIST_list (&LOG_LINKS (insn));
}
-
-
-
\f
/* Main entry point for combiner. F is the first insn of the function.
NREGS is the first unused pseudo-reg number.
#endif
rtx links, nextlinks;
rtx first;
+ basic_block last_bb;
int new_direct_jump_p = 0;
problems when, for example, we have j <<= 1 in a loop. */
nonzero_sign_valid = 0;
+ label_tick = label_tick_ebb_start = 1;
/* Scan all SETs and see if we can deduce anything about what
bits are known to be zero for some registers and how many copies
for what bits are known to be set. */
setup_incoming_promotions (first);
+ /* Allow the entry block and the first block to fall into the same EBB.
+ Conceptually the incoming promotions are assigned to the entry block. */
+ last_bb = ENTRY_BLOCK_PTR;
create_log_links ();
- label_tick_ebb_start = ENTRY_BLOCK_PTR->index;
FOR_EACH_BB (this_basic_block)
{
optimize_this_for_speed_p = optimize_bb_for_speed_p (this_basic_block);
last_call_luid = 0;
mem_last_set = -1;
- label_tick = this_basic_block->index;
+
+ label_tick++;
if (!single_pred_p (this_basic_block)
- || single_pred (this_basic_block)->index != label_tick - 1)
+ || single_pred (this_basic_block) != last_bb)
label_tick_ebb_start = label_tick;
+ last_bb = this_basic_block;
+
FOR_BB_INSNS (this_basic_block, insn)
if (INSN_P (insn) && BLOCK_FOR_INSN (insn))
{
nonzero_sign_valid = 1;
/* Now scan all the insns in forward order. */
-
- label_tick_ebb_start = ENTRY_BLOCK_PTR->index;
+ label_tick = label_tick_ebb_start = 1;
init_reg_last ();
setup_incoming_promotions (first);
+ last_bb = ENTRY_BLOCK_PTR;
FOR_EACH_BB (this_basic_block)
{
optimize_this_for_speed_p = optimize_bb_for_speed_p (this_basic_block);
last_call_luid = 0;
mem_last_set = -1;
- label_tick = this_basic_block->index;
+
+ label_tick++;
if (!single_pred_p (this_basic_block)
- || single_pred (this_basic_block)->index != label_tick - 1)
+ || single_pred (this_basic_block) != last_bb)
label_tick_ebb_start = label_tick;
+ last_bb = this_basic_block;
+
rtl_profile_for_bb (this_basic_block);
for (insn = BB_HEAD (this_basic_block);
insn != NEXT_INSN (BB_END (this_basic_block));
return x;
}
-#endif
/* Auxiliary data structure for propagate_for_debug_stmt. */
struct rtx_subst_pair
{
- rtx from, to;
- bool changed;
-#ifdef AUTO_INC_DEC
+ rtx to;
bool adjusted;
bool after;
-#endif
};
-/* Clean up any auto-updates in PAIR->to the first time it is called
- for a PAIR. PAIR->adjusted is used to tell whether we've cleaned
- up before. */
+/* DATA points to an rtx_subst_pair. Return the value that should be
+ substituted. */
-static void
-auto_adjust_pair (struct rtx_subst_pair *pair ATTRIBUTE_UNUSED)
+static rtx
+propagate_for_debug_subst (rtx from ATTRIBUTE_UNUSED, void *data)
{
-#ifdef AUTO_INC_DEC
+ struct rtx_subst_pair *pair = (struct rtx_subst_pair *)data;
+
if (!pair->adjusted)
{
pair->adjusted = true;
pair->to = cleanup_auto_inc_dec (pair->to, pair->after, VOIDmode);
+ return pair->to;
}
-#endif
-}
-
-/* If *LOC is the same as FROM in the struct rtx_subst_pair passed as
- DATA, replace it with a copy of TO. Handle SUBREGs of *LOC as
- well. */
-
-static int
-propagate_for_debug_subst (rtx *loc, void *data)
-{
- struct rtx_subst_pair *pair = (struct rtx_subst_pair *)data;
- rtx from = pair->from, to = pair->to;
- rtx x = *loc, s = x;
-
- if (rtx_equal_p (x, from)
- || (GET_CODE (x) == SUBREG && rtx_equal_p ((s = SUBREG_REG (x)), from)))
- {
- auto_adjust_pair (pair);
- if (pair->to != to)
- to = pair->to;
- else
- to = copy_rtx (to);
- if (s != x)
- {
- gcc_assert (GET_CODE (x) == SUBREG && SUBREG_REG (x) == s);
- to = simplify_gen_subreg (GET_MODE (x), to,
- GET_MODE (from), SUBREG_BYTE (x));
- }
- *loc = wrap_constant (GET_MODE (x), to);
- pair->changed = true;
- return -1;
- }
-
- return 0;
+ return copy_rtx (pair->to);
}
+#endif
/* Replace occurrences of DEST with SRC in DEBUG_INSNs between INSN
and LAST. If MOVE holds, debug insns must also be moved past
static void
propagate_for_debug (rtx insn, rtx last, rtx dest, rtx src, bool move)
{
- struct rtx_subst_pair p;
- rtx next, move_pos = move ? last : NULL_RTX;
-
- p.from = dest;
- p.to = src;
- p.changed = false;
+ rtx next, move_pos = move ? last : NULL_RTX, loc;
#ifdef AUTO_INC_DEC
+ struct rtx_subst_pair p;
+ p.to = src;
p.adjusted = false;
p.after = move;
#endif
next = NEXT_INSN (insn);
if (DEBUG_INSN_P (insn))
{
- for_each_rtx (&INSN_VAR_LOCATION_LOC (insn),
- propagate_for_debug_subst, &p);
- if (!p.changed)
+#ifdef AUTO_INC_DEC
+ loc = simplify_replace_fn_rtx (INSN_VAR_LOCATION_LOC (insn),
+ dest, propagate_for_debug_subst, &p);
+#else
+ loc = simplify_replace_rtx (INSN_VAR_LOCATION_LOC (insn), dest, src);
+#endif
+ if (loc == INSN_VAR_LOCATION_LOC (insn))
continue;
- p.changed = false;
+ INSN_VAR_LOCATION_LOC (insn) = loc;
if (move_pos)
{
remove_insn (insn);
}
}
-/* Delete the conditional jump INSN and adjust the CFG correspondingly.
+/* Delete the unconditional jump INSN and adjust the CFG correspondingly.
Note that the INSN should be deleted *after* removing dead edges, so
that the kept edge is the fallthrough edge for a (set (pc) (pc))
but not for a (set (pc) (label_ref FOO)). */
update_cfg_for_uncondjump (rtx insn)
{
basic_block bb = BLOCK_FOR_INSN (insn);
+ bool at_end = (BB_END (bb) == insn);
- if (BB_END (bb) == insn)
+ if (at_end)
purge_dead_edges (bb);
delete_insn (insn);
- if (EDGE_COUNT (bb->succs) == 1)
+ if (at_end && EDGE_COUNT (bb->succs) == 1)
single_succ_edge (bb)->flags |= EDGE_FALLTHRU;
}
enum rtx_code outer_code, inner_code;
rtx decomposed, distributed, inner_op0, inner_op1, new_op0, new_op1, tmp;
+ /* Distributivity is not true for floating point as it can change the
+ value. So we don't do it unless -funsafe-math-optimizations. */
+ if (FLOAT_MODE_P (GET_MODE (x))
+ && ! flag_unsafe_math_optimizations)
+ return NULL_RTX;
+
decomposed = XEXP (x, n);
if (!ARITHMETIC_P (decomposed))
return NULL_RTX;
case, we must replace it with (clobber (const_int 0)) to prevent
infinite loops. */
rsp = VEC_index (reg_stat_type, reg_stat, regno);
- if (value && ! get_last_value_validate (&value, insn,
- rsp->last_set_label, 0))
+ if (value && !get_last_value_validate (&value, insn, label_tick, 0))
{
value = copy_rtx (value);
- if (! get_last_value_validate (&value, insn,
- rsp->last_set_label, 1))
+ if (!get_last_value_validate (&value, insn, label_tick, 1))
value = 0;
}
}
}
\f
-/* Utility routine for the following function. Verify that all the registers
- mentioned in *LOC are valid when *LOC was part of a value set when
- label_tick == TICK. Return 0 if some are not.
-
- If REPLACE is nonzero, replace the invalid reference with
- (clobber (const_int 0)) and return 1. This replacement is useful because
- we often can get useful information about the form of a value (e.g., if
- it was produced by a shift that always produces -1 or 0) even though
- we don't know exactly what registers it was produced from. */
+/* Verify that all the registers and memory references mentioned in *LOC are
+ still valid. *LOC was part of a value set in INSN when label_tick was
+ equal to TICK. Return 0 if some are not. If REPLACE is nonzero, replace
+ the invalid references with (clobber (const_int 0)) and return 1. This
+ replacement is useful because we often can get useful information about
+ the form of a value (e.g., if it was produced by a shift that always
+ produces -1 or 0) even though we don't know exactly what registers it
+ was produced from. */
static int
get_last_value_validate (rtx *loc, rtx insn, int tick, int replace)
return 1;
}
- /* If this is a memory reference, make sure that there were
- no stores after it that might have clobbered the value. We don't
- have alias info, so we assume any store invalidates it. */
+ /* If this is a memory reference, make sure that there were no stores after
+ it that might have clobbered the value. We don't have alias info, so we
+ assume any store invalidates it. Moreover, we only have local UIDs, so
+ we also assume that there were stores in the intervening basic blocks. */
else if (MEM_P (x) && !MEM_READONLY_P (x)
- && DF_INSN_LUID (insn) <= mem_last_set)
+ && (tick != label_tick || DF_INSN_LUID (insn) <= mem_last_set))
{
if (replace)
*loc = gen_rtx_CLOBBER (GET_MODE (x), const0_rtx);
return 0;
/* If the value has all its registers valid, return it. */
- if (get_last_value_validate (&value, rsp->last_set,
- rsp->last_set_label, 0))
+ if (get_last_value_validate (&value, rsp->last_set, rsp->last_set_label, 0))
return value;
/* Otherwise, make a copy and replace any invalid register with
(clobber (const_int 0)). If that fails for some reason, return 0. */
value = copy_rtx (value);
- if (get_last_value_validate (&value, rsp->last_set,
- rsp->last_set_label, 1))
+ if (get_last_value_validate (&value, rsp->last_set, rsp->last_set_label, 1))
return value;
return 0;
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