===================================================================
@@ -2915,6 +2915,13 @@ placed in @code{pc} to return to the cal
Note that an insn pattern of @code{(return)} is logically equivalent to
@code{(set (pc) (return))}, but the latter form is never used.
+@findex simple_return
+@item (simple_return)
+Like @code{(return)}, but truly represents only a function return, while
+@code{(return)} may represent an insn that also performs other functions
+of the function epilogue. Like @code{(return)}, this may also occur in
+conditional jumps.
+
@findex call
@item (call @var{function} @var{nargs})
Represents a function call. @var{function} is a @code{mem} expression
@@ -3044,7 +3051,7 @@ Represents several side effects performe
brackets stand for a vector; the operand of @code{parallel} is a
vector of expressions. @var{x0}, @var{x1} and so on are individual
side effect expressions---expressions of code @code{set}, @code{call},
-@code{return}, @code{clobber} or @code{use}.
+@code{return}, @code{simple_return}, @code{clobber} or @code{use}.
``In parallel'' means that first all the values used in the individual
side-effects are computed, and second all the actual side-effects are
@@ -3683,14 +3690,16 @@ and @code{call_insn} insns:
@table @code
@findex PATTERN
@item PATTERN (@var{i})
-An expression for the side effect performed by this insn. This must be
-one of the following codes: @code{set}, @code{call}, @code{use},
-@code{clobber}, @code{return}, @code{asm_input}, @code{asm_output},
-@code{addr_vec}, @code{addr_diff_vec}, @code{trap_if}, @code{unspec},
-@code{unspec_volatile}, @code{parallel}, @code{cond_exec}, or @code{sequence}. If it is a @code{parallel},
-each element of the @code{parallel} must be one these codes, except that
-@code{parallel} expressions cannot be nested and @code{addr_vec} and
-@code{addr_diff_vec} are not permitted inside a @code{parallel} expression.
+An expression for the side effect performed by this insn. This must
+be one of the following codes: @code{set}, @code{call}, @code{use},
+@code{clobber}, @code{return}, @code{simple_return}, @code{asm_input},
+@code{asm_output}, @code{addr_vec}, @code{addr_diff_vec},
+@code{trap_if}, @code{unspec}, @code{unspec_volatile},
+@code{parallel}, @code{cond_exec}, or @code{sequence}. If it is a
+@code{parallel}, each element of the @code{parallel} must be one these
+codes, except that @code{parallel} expressions cannot be nested and
+@code{addr_vec} and @code{addr_diff_vec} are not permitted inside a
+@code{parallel} expression.
@findex INSN_CODE
@item INSN_CODE (@var{i})
===================================================================
@@ -131,6 +131,7 @@ special_rtx (int idx)
|| strcmp (defs[idx].enumname, "PC") == 0
|| strcmp (defs[idx].enumname, "CC0") == 0
|| strcmp (defs[idx].enumname, "RETURN") == 0
+ || strcmp (defs[idx].enumname, "SIMPLE_RETURN") == 0
|| strcmp (defs[idx].enumname, "CONST_VECTOR") == 0);
}
===================================================================
@@ -2492,7 +2492,7 @@ final_scan_insn (rtx insn, FILE *file, i
delete_insn (insn);
break;
}
- else if (GET_CODE (SET_SRC (body)) == RETURN)
+ else if (ANY_RETURN_P (SET_SRC (body)))
/* Replace (set (pc) (return)) with (return). */
PATTERN (insn) = body = SET_SRC (body);
===================================================================
@@ -161,8 +161,11 @@ static rtx *unfilled_firstobj;
#define unfilled_slots_next \
((rtx *) obstack_next_free (&unfilled_slots_obstack))
-/* Points to the label before the end of the function. */
-static rtx end_of_function_label;
+/* Points to the label before the end of the function, or before a
+ return insn. */
+static rtx function_return_label;
+/* Likewise for a simple_return. */
+static rtx function_simple_return_label;
/* Mapping between INSN_UID's and position in the code since INSN_UID's do
not always monotonically increase. */
@@ -175,7 +178,7 @@ static int stop_search_p (rtx, int);
static int resource_conflicts_p (struct resources *, struct resources *);
static int insn_references_resource_p (rtx, struct resources *, bool);
static int insn_sets_resource_p (rtx, struct resources *, bool);
-static rtx find_end_label (void);
+static rtx find_end_label (rtx);
static rtx emit_delay_sequence (rtx, rtx, int);
static rtx add_to_delay_list (rtx, rtx);
static rtx delete_from_delay_slot (rtx);
@@ -231,6 +234,15 @@ first_active_target_insn (rtx insn)
return next_active_insn (insn);
}
+/* Return true iff INSN is a simplejump, or any kind of return insn. */
+
+static bool
+simplejump_or_return_p (rtx insn)
+{
+ return (JUMP_P (insn)
+ && (simplejump_p (insn) || ANY_RETURN_P (PATTERN (insn))));
+}
+
/* Return TRUE if this insn should stop the search for insn to fill delay
slots. LABELS_P indicates that labels should terminate the search.
In all cases, jumps terminate the search. */
@@ -346,23 +358,29 @@ insn_sets_resource_p (rtx insn, struct r
??? There may be a problem with the current implementation. Suppose
we start with a bare RETURN insn and call find_end_label. It may set
- end_of_function_label just before the RETURN. Suppose the machinery
+ function_return_label just before the RETURN. Suppose the machinery
is able to fill the delay slot of the RETURN insn afterwards. Then
- end_of_function_label is no longer valid according to the property
+ function_return_label is no longer valid according to the property
described above and find_end_label will still return it unmodified.
Note that this is probably mitigated by the following observation:
- once end_of_function_label is made, it is very likely the target of
+ once function_return_label is made, it is very likely the target of
a jump, so filling the delay slot of the RETURN will be much more
difficult. */
static rtx
-find_end_label (void)
+find_end_label (rtx kind)
{
rtx insn;
+ rtx *plabel;
+
+ if (kind == ret_rtx)
+ plabel = &function_return_label;
+ else
+ plabel = &function_simple_return_label;
/* If we found one previously, return it. */
- if (end_of_function_label)
- return end_of_function_label;
+ if (*plabel)
+ return *plabel;
/* Otherwise, see if there is a label at the end of the function. If there
is, it must be that RETURN insns aren't needed, so that is our return
@@ -377,44 +395,44 @@ find_end_label (void)
/* When a target threads its epilogue we might already have a
suitable return insn. If so put a label before it for the
- end_of_function_label. */
+ function_return_label. */
if (BARRIER_P (insn)
&& JUMP_P (PREV_INSN (insn))
- && GET_CODE (PATTERN (PREV_INSN (insn))) == RETURN)
+ && PATTERN (PREV_INSN (insn)) == kind)
{
rtx temp = PREV_INSN (PREV_INSN (insn));
- end_of_function_label = gen_label_rtx ();
- LABEL_NUSES (end_of_function_label) = 0;
+ rtx label = gen_label_rtx ();
+ LABEL_NUSES (label) = 0;
/* Put the label before an USE insns that may precede the RETURN insn. */
while (GET_CODE (temp) == USE)
temp = PREV_INSN (temp);
- emit_label_after (end_of_function_label, temp);
+ emit_label_after (label, temp);
+ *plabel = label;
}
else if (LABEL_P (insn))
- end_of_function_label = insn;
+ *plabel = insn;
else
{
- end_of_function_label = gen_label_rtx ();
- LABEL_NUSES (end_of_function_label) = 0;
+ rtx label = gen_label_rtx ();
+ LABEL_NUSES (label) = 0;
/* If the basic block reorder pass moves the return insn to
some other place try to locate it again and put our
- end_of_function_label there. */
- while (insn && ! (JUMP_P (insn)
- && (GET_CODE (PATTERN (insn)) == RETURN)))
+ function_return_label there. */
+ while (insn && ! (JUMP_P (insn) && (PATTERN (insn) == kind)))
insn = PREV_INSN (insn);
if (insn)
{
insn = PREV_INSN (insn);
- /* Put the label before an USE insns that may proceed the
+ /* Put the label before an USE insns that may precede the
RETURN insn. */
while (GET_CODE (insn) == USE)
insn = PREV_INSN (insn);
- emit_label_after (end_of_function_label, insn);
+ emit_label_after (label, insn);
}
else
{
@@ -424,19 +442,16 @@ find_end_label (void)
&& ! HAVE_return
#endif
)
- {
- /* The RETURN insn has its delay slot filled so we cannot
- emit the label just before it. Since we already have
- an epilogue and cannot emit a new RETURN, we cannot
- emit the label at all. */
- end_of_function_label = NULL_RTX;
- return end_of_function_label;
- }
+ /* The RETURN insn has its delay slot filled so we cannot
+ emit the label just before it. Since we already have
+ an epilogue and cannot emit a new RETURN, we cannot
+ emit the label at all. */
+ return NULL_RTX;
#endif /* HAVE_epilogue */
/* Otherwise, make a new label and emit a RETURN and BARRIER,
if needed. */
- emit_label (end_of_function_label);
+ emit_label (label);
#ifdef HAVE_return
/* We don't bother trying to create a return insn if the
epilogue has filled delay-slots; we would have to try and
@@ -455,13 +470,14 @@ find_end_label (void)
}
#endif
}
+ *plabel = label;
}
/* Show one additional use for this label so it won't go away until
we are done. */
- ++LABEL_NUSES (end_of_function_label);
+ ++LABEL_NUSES (*plabel);
- return end_of_function_label;
+ return *plabel;
}
/* Put INSN and LIST together in a SEQUENCE rtx of LENGTH, and replace
@@ -809,10 +825,8 @@ optimize_skip (rtx insn)
if ((next_trial == next_active_insn (JUMP_LABEL (insn))
&& ! (next_trial == 0 && crtl->epilogue_delay_list != 0))
|| (next_trial != 0
- && JUMP_P (next_trial)
- && JUMP_LABEL (insn) == JUMP_LABEL (next_trial)
- && (simplejump_p (next_trial)
- || GET_CODE (PATTERN (next_trial)) == RETURN)))
+ && simplejump_or_return_p (next_trial)
+ && JUMP_LABEL (insn) == JUMP_LABEL (next_trial)))
{
if (eligible_for_annul_false (insn, 0, trial, flags))
{
@@ -831,13 +845,11 @@ optimize_skip (rtx insn)
branch, thread our jump to the target of that branch. Don't
change this into a RETURN here, because it may not accept what
we have in the delay slot. We'll fix this up later. */
- if (next_trial && JUMP_P (next_trial)
- && (simplejump_p (next_trial)
- || GET_CODE (PATTERN (next_trial)) == RETURN))
+ if (next_trial && simplejump_or_return_p (next_trial))
{
rtx target_label = JUMP_LABEL (next_trial);
if (ANY_RETURN_P (target_label))
- target_label = find_end_label ();
+ target_label = find_end_label (target_label);
if (target_label)
{
@@ -951,7 +963,7 @@ rare_destination (rtx insn)
return. */
return 2;
case JUMP_INSN:
- if (GET_CODE (PATTERN (insn)) == RETURN)
+ if (ANY_RETURN_P (PATTERN (insn)))
return 1;
else if (simplejump_p (insn)
&& jump_count++ < 10)
@@ -1366,8 +1378,7 @@ steal_delay_list_from_fallthrough (rtx i
/* We can't do anything if SEQ's delay insn isn't an
unconditional branch. */
- if (! simplejump_p (XVECEXP (seq, 0, 0))
- && GET_CODE (PATTERN (XVECEXP (seq, 0, 0))) != RETURN)
+ if (! simplejump_or_return_p (XVECEXP (seq, 0, 0)))
return delay_list;
for (i = 1; i < XVECLEN (seq, 0); i++)
@@ -2376,7 +2387,7 @@ fill_simple_delay_slots (int non_jumps_p
if (new_label != 0)
new_label = get_label_before (new_label);
else
- new_label = find_end_label ();
+ new_label = find_end_label (simple_return_rtx);
if (new_label)
{
@@ -2508,7 +2519,8 @@ fill_simple_delay_slots (int non_jumps_p
/* Follow any unconditional jump at LABEL;
return the ultimate label reached by any such chain of jumps.
- Return ret_rtx if the chain ultimately leads to a return instruction.
+ Return a suitable return rtx if the chain ultimately leads to a
+ return instruction.
If LABEL is not followed by a jump, return LABEL.
If the chain loops or we can't find end, return LABEL,
since that tells caller to avoid changing the insn. */
@@ -2529,7 +2541,7 @@ follow_jumps (rtx label)
&& JUMP_P (insn)
&& JUMP_LABEL (insn) != NULL_RTX
&& ((any_uncondjump_p (insn) && onlyjump_p (insn))
- || GET_CODE (PATTERN (insn)) == RETURN)
+ || ANY_RETURN_P (PATTERN (insn)))
&& (next = NEXT_INSN (insn))
&& BARRIER_P (next));
depth++)
@@ -2996,16 +3008,14 @@ fill_slots_from_thread (rtx insn, rtx co
gcc_assert (thread_if_true);
- if (new_thread && JUMP_P (new_thread)
- && (simplejump_p (new_thread)
- || GET_CODE (PATTERN (new_thread)) == RETURN)
+ if (new_thread && simplejump_or_return_p (new_thread)
&& redirect_with_delay_list_safe_p (insn,
JUMP_LABEL (new_thread),
delay_list))
new_thread = follow_jumps (JUMP_LABEL (new_thread));
if (ANY_RETURN_P (new_thread))
- label = find_end_label ();
+ label = find_end_label (new_thread);
else if (LABEL_P (new_thread))
label = new_thread;
else
@@ -3355,7 +3365,7 @@ relax_delay_slots (rtx first)
{
target_label = skip_consecutive_labels (follow_jumps (target_label));
if (ANY_RETURN_P (target_label))
- target_label = find_end_label ();
+ target_label = find_end_label (target_label);
if (target_label && next_active_insn (target_label) == next
&& ! condjump_in_parallel_p (insn))
@@ -3370,9 +3380,8 @@ relax_delay_slots (rtx first)
/* See if this jump conditionally branches around an unconditional
jump. If so, invert this jump and point it to the target of the
second jump. */
- if (next && JUMP_P (next)
+ if (next && simplejump_or_return_p (next)
&& any_condjump_p (insn)
- && (simplejump_p (next) || GET_CODE (PATTERN (next)) == RETURN)
&& target_label
&& next_active_insn (target_label) == next_active_insn (next)
&& no_labels_between_p (insn, next))
@@ -3414,8 +3423,7 @@ relax_delay_slots (rtx first)
Don't do this if we expect the conditional branch to be true, because
we would then be making the more common case longer. */
- if (JUMP_P (insn)
- && (simplejump_p (insn) || GET_CODE (PATTERN (insn)) == RETURN)
+ if (simplejump_or_return_p (insn)
&& (other = prev_active_insn (insn)) != 0
&& any_condjump_p (other)
&& no_labels_between_p (other, insn)
@@ -3456,10 +3464,10 @@ relax_delay_slots (rtx first)
Only do so if optimizing for size since this results in slower, but
smaller code. */
if (optimize_function_for_size_p (cfun)
- && GET_CODE (PATTERN (delay_insn)) == RETURN
+ && ANY_RETURN_P (PATTERN (delay_insn))
&& next
&& JUMP_P (next)
- && GET_CODE (PATTERN (next)) == RETURN)
+ && PATTERN (next) == PATTERN (delay_insn))
{
rtx after;
int i;
@@ -3498,6 +3506,8 @@ relax_delay_slots (rtx first)
continue;
target_label = JUMP_LABEL (delay_insn);
+ if (target_label && ANY_RETURN_P (target_label))
+ continue;
if (!ANY_RETURN_P (target_label))
{
@@ -3505,7 +3515,7 @@ relax_delay_slots (rtx first)
don't convert a jump into a RETURN here. */
trial = skip_consecutive_labels (follow_jumps (target_label));
if (ANY_RETURN_P (trial))
- trial = find_end_label ();
+ trial = find_end_label (trial);
if (trial && trial != target_label
&& redirect_with_delay_slots_safe_p (delay_insn, trial, insn))
@@ -3528,7 +3538,7 @@ relax_delay_slots (rtx first)
later incorrectly compute register live/death info. */
rtx tmp = next_active_insn (trial);
if (tmp == 0)
- tmp = find_end_label ();
+ tmp = find_end_label (simple_return_rtx);
if (tmp)
{
@@ -3549,13 +3559,12 @@ relax_delay_slots (rtx first)
if (trial && GET_CODE (PATTERN (trial)) == SEQUENCE
&& XVECLEN (PATTERN (trial), 0) == 2
&& JUMP_P (XVECEXP (PATTERN (trial), 0, 0))
- && (simplejump_p (XVECEXP (PATTERN (trial), 0, 0))
- || GET_CODE (PATTERN (XVECEXP (PATTERN (trial), 0, 0))) == RETURN)
+ && simplejump_or_return_p (XVECEXP (PATTERN (trial), 0, 0))
&& redundant_insn (XVECEXP (PATTERN (trial), 0, 1), insn, 0))
{
target_label = JUMP_LABEL (XVECEXP (PATTERN (trial), 0, 0));
if (ANY_RETURN_P (target_label))
- target_label = find_end_label ();
+ target_label = find_end_label (target_label);
if (target_label
&& redirect_with_delay_slots_safe_p (delay_insn, target_label,
@@ -3633,8 +3642,7 @@ relax_delay_slots (rtx first)
a RETURN here. */
if (! INSN_ANNULLED_BRANCH_P (delay_insn)
&& any_condjump_p (delay_insn)
- && next && JUMP_P (next)
- && (simplejump_p (next) || GET_CODE (PATTERN (next)) == RETURN)
+ && next && simplejump_or_return_p (next)
&& next_active_insn (target_label) == next_active_insn (next)
&& no_labels_between_p (insn, next))
{
@@ -3642,7 +3650,7 @@ relax_delay_slots (rtx first)
rtx old_label = JUMP_LABEL (delay_insn);
if (ANY_RETURN_P (label))
- label = find_end_label ();
+ label = find_end_label (label);
/* find_end_label can generate a new label. Check this first. */
if (label
@@ -3703,7 +3711,8 @@ static void
make_return_insns (rtx first)
{
rtx insn, jump_insn, pat;
- rtx real_return_label = end_of_function_label;
+ rtx real_return_label = function_return_label;
+ rtx real_simple_return_label = function_simple_return_label;
int slots, i;
#ifdef DELAY_SLOTS_FOR_EPILOGUE
@@ -3721,15 +3730,22 @@ make_return_insns (rtx first)
made for END_OF_FUNCTION_LABEL. If so, set up anything we can't change
into a RETURN to jump to it. */
for (insn = first; insn; insn = NEXT_INSN (insn))
- if (JUMP_P (insn) && GET_CODE (PATTERN (insn)) == RETURN)
+ if (JUMP_P (insn) && ANY_RETURN_P (PATTERN (insn)))
{
- real_return_label = get_label_before (insn);
+ rtx t = get_label_before (insn);
+ if (PATTERN (insn) == ret_rtx)
+ real_return_label = t;
+ else
+ real_simple_return_label = t;
break;
}
/* Show an extra usage of REAL_RETURN_LABEL so it won't go away if it
was equal to END_OF_FUNCTION_LABEL. */
- LABEL_NUSES (real_return_label)++;
+ if (real_return_label)
+ LABEL_NUSES (real_return_label)++;
+ if (real_simple_return_label)
+ LABEL_NUSES (real_simple_return_label)++;
/* Clear the list of insns to fill so we can use it. */
obstack_free (&unfilled_slots_obstack, unfilled_firstobj);
@@ -3737,13 +3753,27 @@ make_return_insns (rtx first)
for (insn = first; insn; insn = NEXT_INSN (insn))
{
int flags;
+ rtx kind, real_label;
/* Only look at filled JUMP_INSNs that go to the end of function
label. */
if (!NONJUMP_INSN_P (insn)
|| GET_CODE (PATTERN (insn)) != SEQUENCE
- || !JUMP_P (XVECEXP (PATTERN (insn), 0, 0))
- || JUMP_LABEL (XVECEXP (PATTERN (insn), 0, 0)) != end_of_function_label)
+ || !JUMP_P (XVECEXP (PATTERN (insn), 0, 0)))
+ continue;
+
+ if (JUMP_LABEL (XVECEXP (PATTERN (insn), 0, 0)) == function_return_label)
+ {
+ kind = ret_rtx;
+ real_label = real_return_label;
+ }
+ else if (JUMP_LABEL (XVECEXP (PATTERN (insn), 0, 0))
+ == function_simple_return_label)
+ {
+ kind = simple_return_rtx;
+ real_label = real_simple_return_label;
+ }
+ else
continue;
pat = PATTERN (insn);
@@ -3751,14 +3781,12 @@ make_return_insns (rtx first)
/* If we can't make the jump into a RETURN, try to redirect it to the best
RETURN and go on to the next insn. */
- if (! reorg_redirect_jump (jump_insn, ret_rtx))
+ if (!reorg_redirect_jump (jump_insn, kind))
{
/* Make sure redirecting the jump will not invalidate the delay
slot insns. */
- if (redirect_with_delay_slots_safe_p (jump_insn,
- real_return_label,
- insn))
- reorg_redirect_jump (jump_insn, real_return_label);
+ if (redirect_with_delay_slots_safe_p (jump_insn, real_label, insn))
+ reorg_redirect_jump (jump_insn, real_label);
continue;
}
@@ -3798,7 +3826,7 @@ make_return_insns (rtx first)
RETURN, delete the SEQUENCE and output the individual insns,
followed by the RETURN. Then set things up so we try to find
insns for its delay slots, if it needs some. */
- if (GET_CODE (PATTERN (jump_insn)) == RETURN)
+ if (ANY_RETURN_P (PATTERN (jump_insn)))
{
rtx prev = PREV_INSN (insn);
@@ -3815,13 +3843,16 @@ make_return_insns (rtx first)
else
/* It is probably more efficient to keep this with its current
delay slot as a branch to a RETURN. */
- reorg_redirect_jump (jump_insn, real_return_label);
+ reorg_redirect_jump (jump_insn, real_label);
}
/* Now delete REAL_RETURN_LABEL if we never used it. Then try to fill any
new delay slots we have created. */
- if (--LABEL_NUSES (real_return_label) == 0)
+ if (real_return_label != NULL_RTX && --LABEL_NUSES (real_return_label) == 0)
delete_related_insns (real_return_label);
+ if (real_simple_return_label != NULL_RTX
+ && --LABEL_NUSES (real_simple_return_label) == 0)
+ delete_related_insns (real_simple_return_label);
fill_simple_delay_slots (1);
fill_simple_delay_slots (0);
@@ -3889,7 +3920,7 @@ dbr_schedule (rtx first)
init_resource_info (epilogue_insn);
/* Show we haven't computed an end-of-function label yet. */
- end_of_function_label = 0;
+ function_return_label = function_simple_return_label = NULL_RTX;
/* Initialize the statistics for this function. */
memset (num_insns_needing_delays, 0, sizeof num_insns_needing_delays);
@@ -3911,11 +3942,23 @@ dbr_schedule (rtx first)
/* If we made an end of function label, indicate that it is now
safe to delete it by undoing our prior adjustment to LABEL_NUSES.
If it is now unused, delete it. */
- if (end_of_function_label && --LABEL_NUSES (end_of_function_label) == 0)
- delete_related_insns (end_of_function_label);
+ if (function_return_label && --LABEL_NUSES (function_return_label) == 0)
+ delete_related_insns (function_return_label);
+ if (function_simple_return_label
+ && --LABEL_NUSES (function_simple_return_label) == 0)
+ delete_related_insns (function_simple_return_label);
+#if defined HAVE_return || defined HAVE_simple_return
+ if (
#ifdef HAVE_return
- if (HAVE_return && end_of_function_label != 0)
+ (HAVE_return && function_return_label != 0)
+#else
+ 0
+#endif
+#ifdef HAVE_simple_return
+ || (HAVE_simple_return && function_simple_return_label != 0)
+#endif
+ )
make_return_insns (first);
#endif
===================================================================
@@ -169,6 +169,9 @@ gen_exp (rtx x, enum rtx_code subroutine
case RETURN:
printf ("ret_rtx");
return;
+ case SIMPLE_RETURN:
+ printf ("simple_return_rtx");
+ return;
case CLOBBER:
if (REG_P (XEXP (x, 0)))
{
@@ -489,8 +492,8 @@ gen_expand (rtx expand)
|| (GET_CODE (next) == PARALLEL
&& ((GET_CODE (XVECEXP (next, 0, 0)) == SET
&& GET_CODE (SET_DEST (XVECEXP (next, 0, 0))) == PC)
- || GET_CODE (XVECEXP (next, 0, 0)) == RETURN))
- || GET_CODE (next) == RETURN)
+ || ANY_RETURN_P (XVECEXP (next, 0, 0))))
+ || ANY_RETURN_P (next))
printf (" emit_jump_insn (");
else if ((GET_CODE (next) == SET && GET_CODE (SET_SRC (next)) == CALL)
|| GET_CODE (next) == CALL
@@ -607,7 +610,7 @@ gen_split (rtx split)
|| (GET_CODE (next) == PARALLEL
&& GET_CODE (XVECEXP (next, 0, 0)) == SET
&& GET_CODE (SET_DEST (XVECEXP (next, 0, 0))) == PC)
- || GET_CODE (next) == RETURN)
+ || ANY_RETURN_P (next))
printf (" emit_jump_insn (");
else if ((GET_CODE (next) == SET && GET_CODE (SET_SRC (next)) == CALL)
|| GET_CODE (next) == CALL
===================================================================
@@ -3181,6 +3181,7 @@ df_uses_record (struct df_collection_rec
}
case RETURN:
+ case SIMPLE_RETURN:
break;
case ASM_OPERANDS:
===================================================================
@@ -731,6 +731,10 @@ DEF_RTL_EXPR(ENTRY_VALUE, "entry_value",
been optimized away completely. */
DEF_RTL_EXPR(DEBUG_PARAMETER_REF, "debug_parameter_ref", "t", RTX_OBJ)
+/* A plain return, to be used on paths that are reached without going
+ through the function prologue. */
+DEF_RTL_EXPR(SIMPLE_RETURN, "simple_return", "", RTX_EXTRA)
+
/* All expressions from this point forward appear only in machine
descriptions. */
#ifdef GENERATOR_FILE
===================================================================
@@ -3796,6 +3796,7 @@ find_if_case_1 (basic_block test_bb, edg
basic_block then_bb = then_edge->dest;
basic_block else_bb = else_edge->dest;
basic_block new_bb;
+ rtx else_target = NULL_RTX;
int then_bb_index;
/* If we are partitioning hot/cold basic blocks, we don't want to
@@ -3845,6 +3846,13 @@ find_if_case_1 (basic_block test_bb, edg
predictable_edge_p (then_edge)))))
return FALSE;
+ if (else_bb == EXIT_BLOCK_PTR)
+ {
+ rtx jump = BB_END (else_edge->src);
+ gcc_assert (JUMP_P (jump));
+ else_target = JUMP_LABEL (jump);
+ }
+
/* Registers set are dead, or are predicable. */
if (! dead_or_predicable (test_bb, then_bb, else_bb,
single_succ_edge (then_bb), 1))
@@ -3864,6 +3872,9 @@ find_if_case_1 (basic_block test_bb, edg
redirect_edge_succ (FALLTHRU_EDGE (test_bb), else_bb);
new_bb = 0;
}
+ else if (else_bb == EXIT_BLOCK_PTR)
+ new_bb = force_nonfallthru_and_redirect (FALLTHRU_EDGE (test_bb),
+ else_bb, else_target);
else
new_bb = redirect_edge_and_branch_force (FALLTHRU_EDGE (test_bb),
else_bb);
===================================================================
@@ -29,7 +29,8 @@ along with GCC; see the file COPYING3.
JUMP_LABEL internal field. With this we can detect labels that
become unused because of the deletion of all the jumps that
formerly used them. The JUMP_LABEL info is sometimes looked
- at by later passes.
+ at by later passes. For return insns, it contains either a
+ RETURN or a SIMPLE_RETURN rtx.
The subroutines redirect_jump and invert_jump are used
from other passes as well. */
@@ -775,10 +776,10 @@ condjump_p (const_rtx insn)
return (GET_CODE (x) == IF_THEN_ELSE
&& ((GET_CODE (XEXP (x, 2)) == PC
&& (GET_CODE (XEXP (x, 1)) == LABEL_REF
- || GET_CODE (XEXP (x, 1)) == RETURN))
+ || ANY_RETURN_P (XEXP (x, 1))))
|| (GET_CODE (XEXP (x, 1)) == PC
&& (GET_CODE (XEXP (x, 2)) == LABEL_REF
- || GET_CODE (XEXP (x, 2)) == RETURN))));
+ || ANY_RETURN_P (XEXP (x, 2))))));
}
/* Return nonzero if INSN is a (possibly) conditional jump inside a
@@ -807,11 +808,11 @@ condjump_in_parallel_p (const_rtx insn)
return 0;
if (XEXP (SET_SRC (x), 2) == pc_rtx
&& (GET_CODE (XEXP (SET_SRC (x), 1)) == LABEL_REF
- || GET_CODE (XEXP (SET_SRC (x), 1)) == RETURN))
+ || ANY_RETURN_P (XEXP (SET_SRC (x), 1))))
return 1;
if (XEXP (SET_SRC (x), 1) == pc_rtx
&& (GET_CODE (XEXP (SET_SRC (x), 2)) == LABEL_REF
- || GET_CODE (XEXP (SET_SRC (x), 2)) == RETURN))
+ || ANY_RETURN_P (XEXP (SET_SRC (x), 2))))
return 1;
return 0;
}
@@ -873,8 +874,9 @@ any_condjump_p (const_rtx insn)
a = GET_CODE (XEXP (SET_SRC (x), 1));
b = GET_CODE (XEXP (SET_SRC (x), 2));
- return ((b == PC && (a == LABEL_REF || a == RETURN))
- || (a == PC && (b == LABEL_REF || b == RETURN)));
+ return ((b == PC && (a == LABEL_REF || a == RETURN || a == SIMPLE_RETURN))
+ || (a == PC
+ && (b == LABEL_REF || b == RETURN || b == SIMPLE_RETURN)));
}
/* Return the label of a conditional jump. */
@@ -911,6 +913,7 @@ returnjump_p_1 (rtx *loc, void *data ATT
switch (GET_CODE (x))
{
case RETURN:
+ case SIMPLE_RETURN:
case EH_RETURN:
return true;
===================================================================
@@ -328,6 +328,8 @@ print_rtx (const_rtx in_rtx)
fprintf (outfile, "\n%s%*s -> ", print_rtx_head, indent * 2, "");
if (GET_CODE (JUMP_LABEL (in_rtx)) == RETURN)
fprintf (outfile, "return");
+ else if (GET_CODE (JUMP_LABEL (in_rtx)) == SIMPLE_RETURN)
+ fprintf (outfile, "simple_return");
else
fprintf (outfile, "%d", INSN_UID (JUMP_LABEL (in_rtx)));
}
===================================================================
@@ -558,7 +558,7 @@ compute_defs_uses_and_gen (fibheap_t all
/* Check for sibcall. */
if (GET_CODE (pat) == PARALLEL)
for (i = XVECLEN (pat, 0) - 1; i >= 0; i--)
- if (GET_CODE (XVECEXP (pat, 0, i)) == RETURN)
+ if (ANY_RETURN_P (XVECEXP (pat, 0, i)))
{
COMPL_HARD_REG_SET (call_saved,
call_used_reg_set);
===================================================================
@@ -2518,6 +2518,7 @@ verify_rtx_sharing (rtx orig, rtx insn)
case PC:
case CC0:
case RETURN:
+ case SIMPLE_RETURN:
case SCRATCH:
return;
/* SCRATCH must be shared because they represent distinct values. */
@@ -5002,7 +5003,7 @@ classify_insn (rtx x)
return CODE_LABEL;
if (GET_CODE (x) == CALL)
return CALL_INSN;
- if (GET_CODE (x) == RETURN)
+ if (ANY_RETURN_P (x))
return JUMP_INSN;
if (GET_CODE (x) == SET)
{
@@ -5514,6 +5515,7 @@ init_emit_regs (void)
/* Assign register numbers to the globally defined register rtx. */
pc_rtx = gen_rtx_fmt_ (PC, VOIDmode);
ret_rtx = gen_rtx_fmt_ (RETURN, VOIDmode);
+ simple_return_rtx = gen_rtx_fmt_ (SIMPLE_RETURN, VOIDmode);
cc0_rtx = gen_rtx_fmt_ (CC0, VOIDmode);
stack_pointer_rtx = gen_raw_REG (Pmode, STACK_POINTER_REGNUM);
frame_pointer_rtx = gen_raw_REG (Pmode, FRAME_POINTER_REGNUM);
===================================================================
@@ -767,6 +767,7 @@ fixup_reorder_chain (void)
{
edge e_fall, e_taken, e;
rtx bb_end_insn;
+ rtx ret_label = NULL_RTX;
basic_block nb, src_bb;
edge_iterator ei;
@@ -786,6 +787,7 @@ fixup_reorder_chain (void)
bb_end_insn = BB_END (bb);
if (JUMP_P (bb_end_insn))
{
+ ret_label = JUMP_LABEL (bb_end_insn);
if (any_condjump_p (bb_end_insn))
{
/* This might happen if the conditional jump has side
@@ -899,7 +901,7 @@ fixup_reorder_chain (void)
Note force_nonfallthru can delete E_FALL and thus we have to
save E_FALL->src prior to the call to force_nonfallthru. */
src_bb = e_fall->src;
- nb = force_nonfallthru_and_redirect (e_fall, e_fall->dest);
+ nb = force_nonfallthru_and_redirect (e_fall, e_fall->dest, ret_label);
if (nb)
{
nb->il.rtl->visited = 1;
===================================================================
@@ -256,6 +256,7 @@ copy_rtx (rtx orig)
case PC:
case CC0:
case RETURN:
+ case SIMPLE_RETURN:
case SCRATCH:
/* SCRATCH must be shared because they represent distinct values. */
return orig;
===================================================================
@@ -432,8 +432,9 @@ struct GTY((variable_size)) rtvec_def {
(JUMP_P (INSN) && (GET_CODE (PATTERN (INSN)) == ADDR_VEC || \
GET_CODE (PATTERN (INSN)) == ADDR_DIFF_VEC))
-/* Predicate yielding nonzero iff X is a return. */
-#define ANY_RETURN_P(X) ((X) == ret_rtx)
+/* Predicate yielding nonzero iff X is a return or simple_return. */
+#define ANY_RETURN_P(X) \
+ (GET_CODE (X) == RETURN || GET_CODE (X) == SIMPLE_RETURN)
/* 1 if X is a unary operator. */
@@ -2074,6 +2075,7 @@ enum global_rtl_index
GR_PC,
GR_CC0,
GR_RETURN,
+ GR_SIMPLE_RETURN,
GR_STACK_POINTER,
GR_FRAME_POINTER,
/* For register elimination to work properly these hard_frame_pointer_rtx,
@@ -2169,6 +2171,7 @@ extern struct target_rtl *this_target_rt
/* Standard pieces of rtx, to be substituted directly into things. */
#define pc_rtx (global_rtl[GR_PC])
#define ret_rtx (global_rtl[GR_RETURN])
+#define simple_return_rtx (global_rtl[GR_SIMPLE_RETURN])
#define cc0_rtx (global_rtl[GR_CC0])
/* All references to certain hard regs, except those created
===================================================================
@@ -6303,7 +6303,7 @@ simplify_set (rtx x)
rtx *cc_use;
/* (set (pc) (return)) gets written as (return). */
- if (GET_CODE (dest) == PC && GET_CODE (src) == RETURN)
+ if (GET_CODE (dest) == PC && ANY_RETURN_P (src))
return src;
/* Now that we know for sure which bits of SRC we are using, see if we can
===================================================================
@@ -492,7 +492,7 @@ find_dead_or_set_registers (rtx target,
if (jump_count++ < 10)
{
if (any_uncondjump_p (this_jump_insn)
- || GET_CODE (PATTERN (this_jump_insn)) == RETURN)
+ || ANY_RETURN_P (PATTERN (this_jump_insn)))
{
next = JUMP_LABEL (this_jump_insn);
if (ANY_RETURN_P (next))
@@ -821,7 +821,7 @@ mark_set_resources (rtx x, struct resour
static bool
return_insn_p (const_rtx insn)
{
- if (JUMP_P (insn) && GET_CODE (PATTERN (insn)) == RETURN)
+ if (JUMP_P (insn) && ANY_RETURN_P (PATTERN (insn)))
return true;
if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
===================================================================
@@ -804,7 +804,7 @@ extern rtx block_label (basic_block);
extern bool purge_all_dead_edges (void);
extern bool purge_dead_edges (basic_block);
extern bool fixup_abnormal_edges (void);
-extern basic_block force_nonfallthru_and_redirect (edge, basic_block);
+extern basic_block force_nonfallthru_and_redirect (edge, basic_block, rtx);
/* In cfgbuild.c. */
extern void find_many_sub_basic_blocks (sbitmap);
===================================================================
@@ -554,6 +554,9 @@ print_pattern (char *buf, const_rtx x, i
case RETURN:
sprintf (buf, "return");
break;
+ case SIMPLE_RETURN:
+ sprintf (buf, "simple_return");
+ break;
case CALL:
print_exp (buf, x, verbose);
break;
===================================================================
@@ -29890,7 +29890,7 @@ ix86_pad_returns (void)
rtx prev;
bool replace = false;
- if (!JUMP_P (ret) || GET_CODE (PATTERN (ret)) != RETURN
+ if (!JUMP_P (ret) || !ANY_RETURN_P (PATTERN (ret))
|| optimize_bb_for_size_p (bb))
continue;
for (prev = PREV_INSN (ret); prev; prev = PREV_INSN (prev))
@@ -29941,7 +29941,7 @@ ix86_count_insn_bb (basic_block bb)
{
/* Only happen in exit blocks. */
if (JUMP_P (insn)
- && GET_CODE (PATTERN (insn)) == RETURN)
+ && ANY_RETURN_P (PATTERN (insn)))
break;
if (NONDEBUG_INSN_P (insn)
@@ -30014,7 +30014,7 @@ ix86_pad_short_function (void)
FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
{
rtx ret = BB_END (e->src);
- if (JUMP_P (ret) && GET_CODE (PATTERN (ret)) == RETURN)
+ if (JUMP_P (ret) && ANY_RETURN_P (PATTERN (ret)))
{
int insn_count = ix86_count_insn (e->src);
===================================================================
@@ -17382,6 +17382,7 @@ arm_final_prescan_insn (rtx insn)
/* If we start with a return insn, we only succeed if we find another one. */
int seeking_return = 0;
+ enum rtx_code return_code = UNKNOWN;
/* START_INSN will hold the insn from where we start looking. This is the
first insn after the following code_label if REVERSE is true. */
@@ -17420,7 +17421,7 @@ arm_final_prescan_insn (rtx insn)
else
return;
}
- else if (GET_CODE (body) == RETURN)
+ else if (ANY_RETURN_P (body))
{
start_insn = next_nonnote_insn (start_insn);
if (GET_CODE (start_insn) == BARRIER)
@@ -17431,6 +17432,7 @@ arm_final_prescan_insn (rtx insn)
{
reverse = TRUE;
seeking_return = 1;
+ return_code = GET_CODE (body);
}
else
return;
@@ -17471,11 +17473,15 @@ arm_final_prescan_insn (rtx insn)
label = XEXP (XEXP (SET_SRC (body), 2), 0);
then_not_else = FALSE;
}
- else if (GET_CODE (XEXP (SET_SRC (body), 1)) == RETURN)
- seeking_return = 1;
- else if (GET_CODE (XEXP (SET_SRC (body), 2)) == RETURN)
+ else if (ANY_RETURN_P (XEXP (SET_SRC (body), 1)))
+ {
+ seeking_return = 1;
+ return_code = GET_CODE (XEXP (SET_SRC (body), 1));
+ }
+ else if (ANY_RETURN_P (XEXP (SET_SRC (body), 2)))
{
seeking_return = 1;
+ return_code = GET_CODE (XEXP (SET_SRC (body), 2));
then_not_else = FALSE;
}
else
@@ -17572,12 +17578,11 @@ arm_final_prescan_insn (rtx insn)
}
/* Fail if a conditional return is undesirable (e.g. on a
StrongARM), but still allow this if optimizing for size. */
- else if (GET_CODE (scanbody) == RETURN
+ else if (GET_CODE (scanbody) == return_code
&& !use_return_insn (TRUE, NULL)
&& !optimize_size)
fail = TRUE;
- else if (GET_CODE (scanbody) == RETURN
- && seeking_return)
+ else if (GET_CODE (scanbody) == return_code)
{
arm_ccfsm_state = 2;
succeed = TRUE;
===================================================================
@@ -5724,6 +5724,18 @@ (define_insn "*return"
[(set_attr "type" "jump")
(set_attr "mode" "none")])
+(define_expand "simple_return"
+ [(simple_return)]
+ "!mips_can_use_return_insn ()"
+ { mips_expand_before_return (); })
+
+(define_insn "*simple_return"
+ [(simple_return)]
+ "!mips_can_use_return_insn ()"
+ "%*j\t$31%/"
+ [(set_attr "type" "jump")
+ (set_attr "mode" "none")])
+
;; Normal return.
(define_insn "return_internal"
@@ -5731,6 +5743,14 @@ (define_insn "return_internal"
(use (match_operand 0 "pmode_register_operand" ""))]
""
"%*j\t%0%/"
+ [(set_attr "type" "jump")
+ (set_attr "mode" "none")])
+
+(define_insn "simple_return_internal"
+ [(simple_return)
+ (use (match_operand 0 "pmode_register_operand" ""))]
+ ""
+ "%*j\t%0%/"
[(set_attr "type" "jump")
(set_attr "mode" "none")])
===================================================================
@@ -10452,7 +10452,8 @@ mips_expand_epilogue (bool sibcall_p)
regno = GP_REG_FIRST + 7;
else
regno = RETURN_ADDR_REGNUM;
- emit_jump_insn (gen_return_internal (gen_rtx_REG (Pmode, regno)));
+ emit_jump_insn (gen_simple_return_internal (gen_rtx_REG (Pmode,
+ regno)));
}
}
===================================================================
@@ -1117,10 +1117,13 @@ rtl_redirect_edge_and_branch (edge e, ba
}
/* Like force_nonfallthru below, but additionally performs redirection
- Used by redirect_edge_and_branch_force. */
+ Used by redirect_edge_and_branch_force. JUMP_LABEL is used only
+ when redirecting to the EXIT_BLOCK, it is either ret_rtx or
+ simple_return_rtx, indicating which kind of returnjump to create.
+ It should be NULL otherwise. */
basic_block
-force_nonfallthru_and_redirect (edge e, basic_block target)
+force_nonfallthru_and_redirect (edge e, basic_block target, rtx jump_label)
{
basic_block jump_block, new_bb = NULL, src = e->src;
rtx note;
@@ -1252,12 +1255,25 @@ force_nonfallthru_and_redirect (edge e,
e->flags &= ~EDGE_FALLTHRU;
if (target == EXIT_BLOCK_PTR)
{
+ if (jump_label == ret_rtx)
+ {
#ifdef HAVE_return
- emit_jump_insn_after_setloc (gen_return (), BB_END (jump_block), loc);
- JUMP_LABEL (BB_END (jump_block)) = ret_rtx;
+ emit_jump_insn_after_setloc (gen_return (), BB_END (jump_block), loc);
#else
- gcc_unreachable ();
+ gcc_unreachable ();
+#endif
+ }
+ else
+ {
+ gcc_assert (jump_label == simple_return_rtx);
+#ifdef HAVE_simple_return
+ emit_jump_insn_after_setloc (gen_simple_return (),
+ BB_END (jump_block), loc);
+#else
+ gcc_unreachable ();
#endif
+ }
+ JUMP_LABEL (BB_END (jump_block)) = jump_label;
}
else
{
@@ -1284,7 +1300,7 @@ force_nonfallthru_and_redirect (edge e,
static basic_block
rtl_force_nonfallthru (edge e)
{
- return force_nonfallthru_and_redirect (e, e->dest);
+ return force_nonfallthru_and_redirect (e, e->dest, NULL_RTX);
}
/* Redirect edge even at the expense of creating new jump insn or
@@ -1301,7 +1317,7 @@ rtl_redirect_edge_and_branch_force (edge
/* In case the edge redirection failed, try to force it to be non-fallthru
and redirect newly created simplejump. */
df_set_bb_dirty (e->src);
- return force_nonfallthru_and_redirect (e, target);
+ return force_nonfallthru_and_redirect (e, target, NULL_RTX);
}
/* The given edge should potentially be a fallthru edge. If that is in