common.opt: Add fstrict-overflow.

./:	* common.opt: Add fstrict-overflow.
	* opts.c (decode_options): Set flag_strict_overflow if -O2.
	* flags.h (TYPE_OVERFLOW_WRAPS): Define.
	(TYPE_OVERFLOW_UNDEFINED): Define.
	(TYPE_OVERFLOW_TRAPS): Define.  This replaces TYPE_TRAP_SIGNED.
	Replace all uses.
	* tree.h (TYPE_TRAP_SIGNED): Don't define.
	* fold-const.c (negate_expr_p): Use TYPE_OVERFLOW_UNDEFINED.
	(fold_negate_expr): Likewise.
	(make_range): Likewise.
	(extract_muldiv_1): Likewise.
	(maybe_canonicalize_comparison): Likewise.
	(fold_comparison): Likewise.
	(fold_binary): Likewise.
	(tree_expr_nonnegative_p): Likewise.
	(tree_expr_nonzero_p): Likewise.
	* tree-vrp.c (compare_values): Likewise.
	(extract_range_from_binary_expr): Likewise.
	(extract_range_from_unary_expr): Likewise.
	* tree-ssa-loop-niter.c (infer_loop_bounds_from_signedness):
	Likewise.
	(nowrap_type_p): Likewise.
	* tree-scalar-evolution.c (simple_iv): Likewise.
	* fold-const.c (negate_expr_p): Use TYPE_OVERFLOW_WRAPS.
	(build_range_check): Likewise.
	(extract_muldiv_1): Likewise.
	(fold_comparison): Likewise.
	* tree-vrp.c (vrp_int_const_binop): Likewise.
	(extract_range_from_unary_expr): Likewise.
	* convert.c (convert_to_integer): Likewise.
	* fold-const.c (fold_negate_expr): Use TYPE_OVERFLOW_TRAPS.
	(fold_comparison): Likewise.
	(fold_binary): Likewise.
	* optabs.c (optab_for_tree_code): Likewise.
	* tree-vectorizer.c (vect_is_simple_reduction): Likewise.
	* simplify-rtx.c (simplify_const_relational_operation): Check
	flag_strict_overflow and flag_trapv.
	(simplify_const_relational_operation): Likewise.
	* doc/invoke.texi (Option Summary): Mention -fstrict-overflow.
	(Optimize Options): Add -fstrict-overflow to -O2 list.  Document
	-fstrict-overflow.
testsuite/:
	* gcc.dg/strict-overflow-1.c: New test.
	* gcc.dg/no-strict-overflow-1.c: New test.
	* gcc.dg/strict-overflow-2.c: New test.
	* gcc.dg/no-strict-overflow-2.c: New test.
	* gcc.dg/strict-overflow-3.c: New test.
	* gcc.dg/no-strict-overflow-3.c: New test.
	* gcc.dg/strict-overflow-4.c: New test.
	* gcc.dg/no-strict-overflow-4.c: New test.
	* gcc.dg/fold-mod-1.c: Add -fstrict-overflow option.
	* gcc.dg/pr15784-1.c: Likewise.
	* gcc.dg/pr20922-1.c: Likewise.
	* gcc.dg/pr20922-3.c: Likewise.
	* gcc.dg/pr20922-4.c: Likewise.
	* gcc.dg/pr20922-6.c: Likewise.
	* gcc.dg/compare-4.c: Likewise.
	* gcc.dg/torture/pr26898-1.c: Likewise.
	* gcc.dg/tree-ssa/divide-1.c: Likewise.
	* gcc.dg/tree-ssa/divide-2.c: Likewise.
	* gcc.dg/tree-ssa/divide-3.c: Likewise.
	* gcc.dg/tree-ssa/divide-4.c: Likewise.
	* gcc.dg/tree-ssa/pr14490-1.c: Likewise.
	* gcc.dg/tree-ssa/pr14490-3.c: Likewise.
	* gcc.dg/tree-ssa/pr21082.c: Likewise.
	* gcc.dg/tree-ssa/pr26899.c: Likewise.
	* g++.dg/tree-ssa/pr21082.C: Likewise.

From-SVN: r121254

1 files changed, 5 insertions, 6 deletions

diff --git a/gcc/tree-ssa-loop-niter.c b/gcc/tree-ssa-loop-niter.c
index affb47d..48e045b 100644
--- a/gcc/tree-ssa-loop-niter.c
+++ b/gcc/tree-ssa-loop-niter.c
@@ -1,5 +1,5 @@
 /* Functions to determine/estimate number of iterations of a loop.
-   Copyright (C) 2004, 2005 Free Software Foundation, Inc.
+   Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
    
 This file is part of GCC.
    
@@ -1874,7 +1874,7 @@ infer_loop_bounds_from_signedness (struct loop *loop, tree stmt)
 {
   tree def, base, step, scev, type, low, high;
 
-  if (flag_wrapv || TREE_CODE (stmt) != GIMPLE_MODIFY_STMT)
+  if (TREE_CODE (stmt) != GIMPLE_MODIFY_STMT)
     return;
 
   def = GIMPLE_STMT_OPERAND (stmt, 0);
@@ -1884,7 +1884,7 @@ infer_loop_bounds_from_signedness (struct loop *loop, tree stmt)
 
   type = TREE_TYPE (def);
   if (!INTEGRAL_TYPE_P (type)
-      || TYPE_UNSIGNED (type))
+      || !TYPE_OVERFLOW_UNDEFINED (type))
     return;
 
   scev = instantiate_parameters (loop, analyze_scalar_evolution (loop, def));
@@ -2094,9 +2094,8 @@ n_of_executions_at_most (tree stmt,
 bool
 nowrap_type_p (tree type)
 {
-  if (!flag_wrapv
-      && INTEGRAL_TYPE_P (type)
-      && !TYPE_UNSIGNED (type))
+  if (INTEGRAL_TYPE_P (type)
+      && TYPE_OVERFLOW_UNDEFINED (type))
     return true;
 
   if (POINTER_TYPE_P (type))