re PR tree-optimization/37991 (excessive memory consumption - possible hang)

2008-11-02  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/37991
	* tree-ssa-sccvn.h (copy_vuses_from_stmt): Remove.
	* tree-ssa-sccvn.c (copy_vuses_from_stmt): Make static.
	(set_ssa_val_to): Print if the value changed.
	(simplify_binary_expression): Strip useless conversions.

	* gcc.c-torture/compile/pr37991.c: New testcase.

From-SVN: r141532

gcc/ChangeLog

+2008-11-02  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/37991
+	* tree-ssa-sccvn.h (copy_vuses_from_stmt): Remove.
+	* tree-ssa-sccvn.c (copy_vuses_from_stmt): Make static.
+	(set_ssa_val_to): Print if the value changed.
+	(simplify_binary_expression): Strip useless conversions.
+
 2008-11-01  Hans-Peter Nilsson  <hp@axis.com>
 
 	PR target/37939

gcc/testsuite/ChangeLog

+2008-11-02  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/37991
+	* gcc.c-torture/compile/pr37991.c: New testcase.
+
 2008-11-01  Hans-Peter Nilsson  <hp@axis.com>
 
 	PR target/37939

gcc/testsuite/gcc.c-torture/compile/pr37991.c

+typedef int Int32;
+void use_it(int);
+void FindAndReadSignature(int processedSize)
+{
+  int numPrevBytes = 1;
+  for (;;)
+    {
+      int numBytesInBuffer = numPrevBytes + processedSize;
+      Int32 numTests = numBytesInBuffer - 1;
+      use_it (numTests);
+      numPrevBytes = numBytesInBuffer - numTests;
+    }
+}
+

gcc/tree-ssa-sccvn.c

@@ -498,7 +498,7 @@ vuses_to_vec (gimple stmt, VEC (tree, gc) **result)
 /* Copy the VUSE names in STMT into a vector, and return
    the vector.  */
 
-VEC (tree, gc) *
+static VEC (tree, gc) *
 copy_vuses_from_stmt (gimple stmt)
 {
   VEC (tree, gc) *vuses = NULL;
@@ -1579,7 +1579,6 @@ set_ssa_val_to (tree from, tree to)
       print_generic_expr (dump_file, from, 0);
       fprintf (dump_file, " to ");
       print_generic_expr (dump_file, to, 0);
-      fprintf (dump_file, "\n");
     }
 
   currval = SSA_VAL (from);
@@ -1587,8 +1586,12 @@ set_ssa_val_to (tree from, tree to)
   if (currval != to  && !operand_equal_p (currval, to, OEP_PURE_SAME))
     {
       SSA_VAL (from) = to;
+      if (dump_file && (dump_flags & TDF_DETAILS))
+	fprintf (dump_file, " (changed)\n");
       return true;
     }
+  if (dump_file && (dump_flags & TDF_DETAILS))
+    fprintf (dump_file, "\n");
   return false;
 }
 
@@ -2113,6 +2116,8 @@ simplify_binary_expression (gimple stmt)
 
   result = fold_binary (gimple_assign_rhs_code (stmt),
 			TREE_TYPE (gimple_get_lhs (stmt)), op0, op1);
+  if (result)
+    STRIP_USELESS_TYPE_CONVERSION (result);
 
   fold_undefer_overflow_warnings (result && valid_gimple_rhs_p (result),
 				  stmt, 0);

gcc/tree-ssa-sccvn.h

@@ -196,5 +196,4 @@ unsigned int get_constant_value_id (tree);
 unsigned int get_or_alloc_constant_value_id (tree);
 bool value_id_constant_p (unsigned int);
 VEC (tree, gc) *shared_vuses_from_stmt (gimple);
-VEC (tree, gc) *copy_vuses_from_stmt (gimple);
 #endif /* TREE_SSA_SCCVN_H  */