This should fix PR57081 - the problem is that number-of-iteration
estimates are not freed by DCE and thus possibly dead stmts are looked
at in loop prediction. The fix is to always free number-of-iteration
estimates at loop_optimizer_finalize time (this is the behavior
from before preserving loops at all).
Bootstrap & regtest pending on x86_64-unknown-linux-gnu.
Richard.
2013-04-26 Richard Biener <rguent...@suse.de>
PR tree-optimization/57081
* loop-init.c: Include tree-flow.h.
(loop_optimizer_finalize): Free number of iteration estimates.
* Makefile.in (loop-init.o): Add $(TREE_FLOW_H) dependency.
* gcc.dg/torture/pr57081.c: New testcase.
Index: gcc/loop-init.c
===================================================================
*** gcc/loop-init.c (revision 198334)
--- gcc/loop-init.c (working copy)
*************** along with GCC; see the file COPYING3.
*** 30,35 ****
--- 30,36 ----
#include "flags.h"
#include "df.h"
#include "ggc.h"
+ #include "tree-flow.h"
/* Apply FLAGS to the loop state. */
*************** loop_optimizer_finalize (void)
*** 142,147 ****
--- 143,150 ----
if (loops_state_satisfies_p (LOOPS_HAVE_RECORDED_EXITS))
release_recorded_exits ();
+ free_numbers_of_iterations_estimates ();
+
/* If we should preserve loop structure, do not free it but clear
flags that advanced properties are there as we are not preserving
that in full. */
Index: gcc/Makefile.in
===================================================================
*** gcc/Makefile.in (revision 198334)
--- gcc/Makefile.in (working copy)
*************** cfgloopmanip.o : cfgloopmanip.c $(CONFIG
*** 3181,3187 ****
loop-init.o : loop-init.c $(CONFIG_H) $(SYSTEM_H) $(RTL_H) $(GGC_H) \
$(BASIC_BLOCK_H) hard-reg-set.h $(CFGLOOP_H) \
coretypes.h $(TM_H) $(OBSTACK_H) $(TREE_PASS_H) $(FLAGS_H) \
! $(REGS_H) $(DF_H)
loop-unswitch.o : loop-unswitch.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \
$(DUMPFILE_H) \
$(RTL_H) $(TM_H) $(BASIC_BLOCK_H) hard-reg-set.h $(CFGLOOP_H) $(PARAMS_H) \
--- 3189,3195 ----
loop-init.o : loop-init.c $(CONFIG_H) $(SYSTEM_H) $(RTL_H) $(GGC_H) \
$(BASIC_BLOCK_H) hard-reg-set.h $(CFGLOOP_H) \
coretypes.h $(TM_H) $(OBSTACK_H) $(TREE_PASS_H) $(FLAGS_H) \
! $(REGS_H) $(DF_H) $(TREE_FLOW_H)
loop-unswitch.o : loop-unswitch.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \
$(DUMPFILE_H) \
$(RTL_H) $(TM_H) $(BASIC_BLOCK_H) hard-reg-set.h $(CFGLOOP_H) $(PARAMS_H) \
Index: gcc/testsuite/gcc.dg/torture/pr57081.c
===================================================================
*** gcc/testsuite/gcc.dg/torture/pr57081.c (revision 0)
--- gcc/testsuite/gcc.dg/torture/pr57081.c (working copy)
***************
*** 0 ****
--- 1,22 ----
+ /* { dg-do compile } */
+
+ int a;
+
+ void f(void)
+ {
+ int b;
+
+ if(0)
+ lbl:
+ goto lbl;
+
+ if(b)
+ {
+ int p = 0;
+ goto lbl;
+ }
+
+ a = 0;
+ while(b++);
+ goto lbl;
+ }
