Re: [PATCH, SMS] Fix PR51794

[Ayal Zaks]

On Tue, Jan 10, 2012 at 12:31 PM, Revital1 Eres e...@il.ibm.com wrote:

 Hello,

 The patch below fixes ICE reported in PR51794.
 It avoids creating DDG edges  for register uses of class DF_REF_ARTIFICIAL
 as
 the latter does not have real instructions for them and thus calling
 BLOCK_FOR_INSN fails.

 Tested and bootstrap on ppc64-redhat-linux, enabling SMS on loops with SC
 1.

 OK for mainline?


Yes, this is ok.
Thanks,
Ayal.

 Thanks,
 Revital

 Chanelog:

        PR rtl-optimization/51794
        * ddg.c (add_cross_iteration_register_deps): Avoid
        creating edges for uses of class DF_REF_ARTIFICIAL.

 testsuite/
        PR rtl-optimization/51794
        * gcc.dg/sms-12.c: New test.

 (See attached file: patch_fix_pr51794.txt)

[PATCH, SMS] Fix PR51794

[Revital1 Eres]

Hello,

The patch below fixes ICE reported in PR51794.
It avoids creating DDG edges  for register uses of class DF_REF_ARTIFICIAL
as
the latter does not have real instructions for them and thus calling
BLOCK_FOR_INSN fails.

Tested and bootstrap on ppc64-redhat-linux, enabling SMS on loops with SC
1.

OK for mainline?

Thanks,
Revital

Chanelog:

PR rtl-optimization/51794
* ddg.c (add_cross_iteration_register_deps): Avoid
creating edges for uses of class DF_REF_ARTIFICIAL.

testsuite/
PR rtl-optimization/51794
* gcc.dg/sms-12.c: New test.

(See attached file: patch_fix_pr51794.txt)Index: ddg.c
===
--- ddg.c   (revision 183001)
+++ ddg.c   (working copy)
@@ -315,7 +315,12 @@ add_cross_iteration_register_deps (ddg_p
   /* Create inter-loop true dependences and anti dependences.  */
   for (r_use = DF_REF_CHAIN (last_def); r_use != NULL; r_use = r_use-next)
 {
-  rtx use_insn = DF_REF_INSN (r_use-ref);
+  rtx use_insn;
+
+  if (r_use-ref == NULL || DF_REF_CLASS (r_use-ref) == DF_REF_ARTIFICIAL)
+   continue;
+
+  use_insn = DF_REF_INSN (r_use-ref);
 
   if (BLOCK_FOR_INSN (use_insn) != g-bb)
continue;
Index: testsuite/gcc.dg/sms-12.c
===
--- testsuite/gcc.dg/sms-12.c   (revision 0)
+++ testsuite/gcc.dg/sms-12.c   (revision 0)
@@ -0,0 +1,13 @@
+ /* { dg-do compile } */
+ /* { dg-options -O -fmodulo-sched } */
+
+
+int
+res_inverse (int a)
+{
+  int i;
+  char **b = (char **) __builtin_alloca (a * sizeof (char *));
+  for (i = 0; i  a; i++)
+b[i] = (char *) __builtin_alloca (sizeof (*b[i]));
+  return 0;
+}