re PR tree-optimization/42398 (internal compiler error: in sra_modify_expr, at tree-sra.c:2175)

2010-01-04  Martin Jambor  <mjambor@suse.cz>

	PR tree-optimization/42398
	* tree-sra.c (struct access): Removed flag grp_different_types.
	(dump_access): Do not dump the removed flag.
	(sort_and_splice_var_accesses): Do not set the removed flag.
	(sra_modify_expr): Check for type compatibility directly.

	* testsuite/gcc.c-torture/compile/pr42398.c: New test.

From-SVN: r155631

gcc/ChangeLog

 2010-01-04  Martin Jambor  <mjambor@suse.cz>
 
+	PR tree-optimization/42398
+	* tree-sra.c (struct access): Removed flag grp_different_types.
+	(dump_access): Do not dump the removed flag.
+	(sort_and_splice_var_accesses): Do not set the removed flag.
+	(sra_modify_expr): Check for type compatibility directly.
+
+2010-01-04  Martin Jambor  <mjambor@suse.cz>
+
 	PR tree-optimization/42366
 	* ipa-cp.c (ipcp_init_stage): Always call ipa_compute_jump_functions on
 	edges with variable number of parameters.

gcc/testsuite/ChangeLog

+2010-01-04  Martin Jambor  <mjambor@suse.cz>
+
+	PR tree-optimization/42398
+	* gcc.c-torture/compile/pr42398.c: New test.
+
 2010-01-04  Jason Merrill  <jason@redhat.com>
 
 	PR c++/42555

gcc/testsuite/gcc.c-torture/compile/pr42398.c

+int ptrace_setregs(void)
+{
+  union { unsigned int l; int t; } __gu_tmp;
+  __asm__ __volatile__("" : "=r" (__gu_tmp.l));
+  return __gu_tmp.t;
+}

gcc/tree-sra.c

@@ -199,10 +199,6 @@ struct access
      BIT_FIELD_REF?  */
   unsigned grp_partial_lhs : 1;
 
-  /* Does this group contain accesses to different types? (I.e. through a union
-     or a similar mechanism).  */
-  unsigned grp_different_types : 1;
-
   /* Set when a scalar replacement should be created for this variable.  We do
      the decision and creation at different places because create_tmp_var
      cannot be called from within FOR_EACH_REFERENCED_VAR. */
@@ -343,14 +339,12 @@ dump_access (FILE *f, struct access *access, bool grp)
     fprintf (f, ", grp_write = %d, grp_read = %d, grp_hint = %d, "
 	     "grp_covered = %d, grp_unscalarizable_region = %d, "
 	     "grp_unscalarized_data = %d, grp_partial_lhs = %d, "
-	     "grp_different_types = %d, grp_to_be_replaced = %d, "
-	     "grp_maybe_modified = %d, "
+	     "grp_to_be_replaced = %d, grp_maybe_modified = %d, "
 	     "grp_not_necessarilly_dereferenced = %d\n",
 	     access->grp_write, access->grp_read, access->grp_hint,
 	     access->grp_covered, access->grp_unscalarizable_region,
 	     access->grp_unscalarized_data, access->grp_partial_lhs,
-	     access->grp_different_types, access->grp_to_be_replaced,
-	     access->grp_maybe_modified,
+	     access->grp_to_be_replaced, access->grp_maybe_modified,
 	     access->grp_not_necessarilly_dereferenced);
   else
     fprintf (f, ", write = %d, grp_partial_lhs = %d\n", access->write,
@@ -1434,7 +1428,6 @@ sort_and_splice_var_accesses (tree var)
       bool grp_read = !access->write;
       bool multiple_reads = false;
       bool grp_partial_lhs = access->grp_partial_lhs;
-      bool grp_different_types = false;
       bool first_scalar = is_gimple_reg_type (access->type);
       bool unscalarizable_region = access->grp_unscalarizable_region;
 
@@ -1466,7 +1459,6 @@ sort_and_splice_var_accesses (tree var)
 		grp_read = true;
 	    }
 	  grp_partial_lhs |= ac2->grp_partial_lhs;
-	  grp_different_types |= !types_compatible_p (access->type, ac2->type);
 	  unscalarizable_region |= ac2->grp_unscalarizable_region;
 	  relink_to_new_repr (access, ac2);
 
@@ -1485,7 +1477,6 @@ sort_and_splice_var_accesses (tree var)
       access->grp_read = grp_read;
       access->grp_hint = multiple_reads;
       access->grp_partial_lhs = grp_partial_lhs;
-      access->grp_different_types = grp_different_types;
       access->grp_unscalarizable_region = unscalarizable_region;
       if (access->first_link)
 	add_access_to_work_queue (access);
@@ -2141,11 +2132,9 @@ sra_modify_expr (tree *expr, gimple_stmt_iterator *gsi, bool write,
 
          We also want to use this when accessing a complex or vector which can
          be accessed as a different type too, potentially creating a need for
-         type conversion  (see PR42196).  */
-      if (!is_gimple_reg_type (type)
-	  || (access->grp_different_types
-	      && (TREE_CODE (type) == COMPLEX_TYPE
-		  || TREE_CODE (type) == VECTOR_TYPE)))
+         type conversion (see PR42196) and when scalarized unions are involved
+         in assembler statements (see PR42398).  */
+      if (!useless_type_conversion_p (type, access->type))
 	{
 	  tree ref = access->base;
 	  bool ok;
@@ -2176,10 +2165,7 @@ sra_modify_expr (tree *expr, gimple_stmt_iterator *gsi, bool write,
 	    }
 	}
       else
-	{
-	  gcc_assert (useless_type_conversion_p (type, access->type));
 	*expr = repl;
-	}
       sra_stats.exprs++;
     }