The following patch fixes
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55775
The bug is related to PR55330.
The patch was successfully bootstrapped and tested on x86/x86-64.
Committed as rev. 194680.
2012-12-21 Vladimir Makarov
PR middle-end/55775
* lra-assigns.c (improve_inheritance): Do nothing after
LRA_MAX_INHERITANCE_PASSES pass.
* lra-constraints.c (MAX_CONSTRAINT_ITERATION_NUMBER): Rename to
LRA_MAX_CONSTRAINT_ITERATION_NUMBER. Move to lra-int.h.
(MAX_INHERITANCE_PASSES): Rename to LRA_MAX_INHERITANCE_PASSES.
Move to lra-int.h.
* lra-int.h (LRA_MAX_CONSTRAINT_ITERATION_NUMBER): Move from
lra-constraints.c.
(LRA_MAX_INHERITANCE_PASSES): Ditto.
2012-12-21 Vladimir Makarov
PR middle-end/55775
* gcc.target/i386/pr55775.c: New test.
Index: lra-assigns.c
===
--- lra-assigns.c (revision 194677)
+++ lra-assigns.c (working copy)
@@ -1084,6 +1084,8 @@ improve_inheritance (bitmap changed_pseu
lra_copy_t cp, next_cp;
bitmap_iterator bi;
+ if (lra_inheritance_iter > LRA_MAX_INHERITANCE_PASSES)
+return;
n = 0;
EXECUTE_IF_SET_IN_BITMAP (&lra_inheritance_pseudos, 0, k, bi)
if (reg_renumber[k] >= 0 && lra_reg_info[k].nrefs != 0)
Index: lra-constraints.c
===
--- lra-constraints.c (revision 194677)
+++ lra-constraints.c (working copy)
@@ -3201,10 +3201,6 @@ loc_equivalence_callback (rtx loc, const
return NULL_RTX;
}
-/* Maximum allowed number of constraint pass iterations after the last
- spill pass. It is for preventing LRA cycling in a bug case. */
-#define MAX_CONSTRAINT_ITERATION_NUMBER 30
-
/* Maximum number of generated reload insns per an insn. It is for
preventing this pass cycling in a bug case. */
#define MAX_RELOAD_INSNS_NUMBER LRA_MAX_INSN_RELOADS
@@ -3328,10 +3324,10 @@ lra_constraints (bool first_p)
fprintf (lra_dump_file, "\n** Local #%d: **\n\n",
lra_constraint_iter);
lra_constraint_iter_after_spill++;
- if (lra_constraint_iter_after_spill > MAX_CONSTRAINT_ITERATION_NUMBER)
+ if (lra_constraint_iter_after_spill > LRA_MAX_CONSTRAINT_ITERATION_NUMBER)
internal_error
("Maximum number of LRA constraint passes is achieved (%d)\n",
- MAX_CONSTRAINT_ITERATION_NUMBER);
+ LRA_MAX_CONSTRAINT_ITERATION_NUMBER);
changed_p = false;
lra_risky_transformations_p = false;
new_insn_uid_start = get_max_uid ();
@@ -4698,21 +4694,6 @@ inherit_in_ebb (rtx head, rtx tail)
return change_p;
}
-/* The maximal number of inheritance/split passes in LRA. It should
- be more 1 in order to perform caller saves transformations and much
- less MAX_CONSTRAINT_ITERATION_NUMBER to prevent LRA to do as many
- as permitted constraint passes in some complicated cases. The
- first inheritance/split pass has a biggest impact on generated code
- quality. Each subsequent affects generated code in less degree.
- For example, the 3rd pass does not change generated SPEC2000 code
- at all on x86-64. */
-#define MAX_INHERITANCE_PASSES 2
-
-#if MAX_INHERITANCE_PASSES <= 0 \
-|| MAX_INHERITANCE_PASSES >= MAX_CONSTRAINT_ITERATION_NUMBER - 8
-#error wrong MAX_INHERITANCE_PASSES value
-#endif
-
/* This value affects EBB forming. If probability of edge from EBB to
a BB is not greater than the following value, we don't add the BB
to EBB. */
@@ -4730,7 +4711,7 @@ lra_inheritance (void)
edge e;
lra_inheritance_iter++;
- if (lra_inheritance_iter > MAX_INHERITANCE_PASSES)
+ if (lra_inheritance_iter > LRA_MAX_INHERITANCE_PASSES)
return;
timevar_push (TV_LRA_INHERITANCE);
if (lra_dump_file != NULL)
@@ -5000,7 +4981,7 @@ lra_undo_inheritance (void)
bool change_p;
lra_undo_inheritance_iter++;
- if (lra_undo_inheritance_iter > MAX_INHERITANCE_PASSES)
+ if (lra_undo_inheritance_iter > LRA_MAX_INHERITANCE_PASSES)
return false;
if (lra_dump_file != NULL)
fprintf (lra_dump_file,
Index: lra-int.h
===
--- lra-int.h (revision 194677)
+++ lra-int.h (working copy)
@@ -249,6 +249,25 @@ typedef struct lra_insn_recog_data *lra_
#define LRA_LOSER_COST_FACTOR 6
#define LRA_MAX_REJECT 600
+/* Maximum allowed number of constraint pass iterations after the last
+ spill pass. It is for preventing LRA cycling in a bug case. */
+#define LRA_MAX_CONSTRAINT_ITERATION_NUMBER 30
+
+/* The maximal number of inheritance/split passes in LRA. It should
+ be more 1 in order to perform caller saves transformations and much
+ less MAX_CONSTRAINT_ITERATION_NUMBER to prevent LRA to do as many
+ as permitted constraint passes in some complicated cases. The
+ first inheritance/split pass has a biggest impact on generated code
+ quality. Each subsequent affects generated
