[PATCH] Fix PR54782

[Dehao Chen]

Hi,

Attached patch fixes PR54782. phi_arg_location is not correctly
updated in move_block_to_fn. This patch fixes the problem.

Bootstrapped and passed gcc regression tests on x86.

Okay for trunk?

Thanks,
Dehao

gcc/ChangeLog:
2012-10-03  Dehao Chen  <de...@google.com>

PR middle-end/54782
* tree-cfg.c (move_block_to_fn): Update lexical block for phi_args.

gcc/testsuite/ChangeLog:
2012-10-03  Dehao Chen  <de...@google.com>

PR middle-end/54782
* gcc.dg/pr54782.c: New test.

Index: gcc/tree-cfg.c
===================================================================
--- gcc/tree-cfg.c      (revision 192041)
+++ gcc/tree-cfg.c      (working copy)
@@ -6322,6 +6322,7 @@ move_block_to_fn (struct function *dest_cfun, basi
       use_operand_p use;
       tree op = PHI_RESULT (phi);
       ssa_op_iter oi;
+      unsigned i;
 
       if (virtual_operand_p (op))
        {
@@ -6340,6 +6341,20 @@ move_block_to_fn (struct function *dest_cfun, basi
            SET_USE (use, replace_ssa_name (op, d->vars_map, dest_cfun->decl));
        }
 
+      for (i = 0; i < EDGE_COUNT (bb->preds); i++)
+       {
+         location_t locus = gimple_phi_arg_location (phi, i);
+         if (locus != UNKNOWN_LOCATION)
+           {
+             tree block = LOCATION_BLOCK (locus);
+             if (d->orig_block == NULL_TREE
+                 || block == d->orig_block)
+               gimple_phi_arg_set_location (phi, i, d->new_block ?
+                   COMBINE_LOCATION_DATA (line_table, locus, d->new_block) :
+                   LOCATION_LOCUS (locus));
+           }
+       }
+
       gsi_next (&si);
     }
 
Index: gcc/testsuite/gcc.dg/pr54782.c
===================================================================
--- gcc/testsuite/gcc.dg/pr54782.c      (revision 0)
+++ gcc/testsuite/gcc.dg/pr54782.c      (revision 0)
@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-O -ffast-math -ftree-parallelize-loops=2 -g" } */
+
+struct S
+{
+  int n;
+  float *a;
+};
+
+int
+foo (struct S *s)
+{
+  float sum = 0;
+  int i;
+  for (i = 0; i < s->n; i++)
+    sum += s->a[i];
+  return sum;
+}