Andrey Belevantsev wrote:
Vladimir Makarov wrote:
I'll look at this PR today.
We've looked today at this issue. We think the problem is that
proposed patch of sched_get_condition() treats conditional jumps
likely to COND_EXECs, but it doesn't fix other places in sched-deps,
where COND_EXECs are considered. Maxim Kuvyrkov proposed the attached
patch, which allows gcc to bootstrap on ia64 and fixes the testcase in
PR.
This patch is ok to fix PR17808. You just need to remove conditional
#if and Richard's comment in sched_get_condition.
We've also found that current mainline ICEs compiling the testcase
with "-O0 -fschedule-insns -fschedule-insns2". That is because after
reload several pseudos still remain in global_live_at_start sets. The
pseudos then appear in regsets through
compute_jump_reg_dependencies(), and sched-deps segfaults at
EXECUTE_IF_SET_IN_REG_SET loop at sched-deps.c:948.
We don't know reload well enough to know for sure which place should
be fixed in reload, or maybe in update_life_info(). Is this issue
worth opening another PR?
As Jim Wilson wrote some combinations of options for IA64 are not
supposed to work since starting the port implementation.
Andrey
------------------------------------------------------------------------
--- gcc/gcc/sched-deps.c Sun Jun 19 16:37:49 2005
+++ orig/gcc/sched-deps.c Thu Jun 30 18:00:23 2005
@@ -149,7 +149,7 @@
return 0;
src = SET_SRC (pc_set (insn));
-#if 0
+#if 1
/* The previous code here was completely invalid and could never extract
the condition from a jump. This code does the correct thing, but that
triggers latent bugs later in the scheduler on ports with conditional
@@ -1019,7 +1019,8 @@
{
/* In the case of barrier the most added dependencies are not
real, so we use anti-dependence here. */
- if (GET_CODE (PATTERN (insn)) == COND_EXEC)
+ /* if (GET_CODE (PATTERN (insn)) == COND_EXEC) */
+ if (sched_get_condition (insn))
{
EXECUTE_IF_SET_IN_REG_SET (&deps->reg_last_in_use, 0, i, rsi)
{
@@ -1066,7 +1067,8 @@
{
/* If the current insn is conditional, we can't free any
of the lists. */
- if (GET_CODE (PATTERN (insn)) == COND_EXEC)
+ /* if (GET_CODE (PATTERN (insn)) == COND_EXEC) */
+ if (sched_get_condition (insn))
{
EXECUTE_IF_SET_IN_REG_SET (reg_pending_uses, 0, i, rsi)
{
