--- gcc/opts.c.mp	2013-11-21 14:08:55.029796721 +0100
+++ gcc/opts.c	2013-11-21 14:09:00.526816708 +0100
@@ -1458,6 +1458,8 @@ common_handle_option (struct gcc_options
 		sizeof "unreachable" - 1 },
 	      { "vla-bound", SANITIZE_VLA, sizeof "vla-bound" - 1 },
 	      { "null", SANITIZE_NULL, sizeof "null" - 1 },
+	      { "signed-integer-overflow", SANITIZE_SI_OVERFLOW,
+		sizeof "signed-integer-overflow" -1 },
 	      { NULL, 0, 0 }
 	    };
 	    const char *comma;
--- gcc/config/i386/i386.md.mp	2013-11-21 15:28:13.967939859 +0100
+++ gcc/config/i386/i386.md	2013-11-21 19:29:42.438417911 +0100
@@ -6198,6 +6198,42 @@
   [(set_attr "type" "alu")
    (set_attr "mode" "QI")])
 
+(define_mode_attr widerintmode [(QI "HI") (HI "SI") (SI "DI") (DI "TI")])
+
+;; Add with jump on overflow.
+(define_expand "addv<mode>4"
+  [(parallel [(set (reg:CCO FLAGS_REG)
+		   (eq:CCO (plus:<widerintmode>
+			      (sign_extend:<widerintmode>
+				 (match_operand:SWI 1 "register_operand"))
+			      (sign_extend:<widerintmode>
+				 (match_operand:SWI 2 "<general_operand>")))
+			   (sign_extend:<widerintmode>
+			      (plus:SWI (match_dup 1) (match_dup 2)))))
+	      (set (match_operand:SWI 0 "register_operand")
+		   (plus:SWI (match_dup 1) (match_dup 2)))])
+   (set (pc) (if_then_else
+	       (eq (reg:CCO FLAGS_REG) (const_int 0))
+	       (label_ref (match_operand 3))
+	       (pc)))]
+  "")
+
+(define_insn "*addv<mode>4"
+  [(set (reg:CCO FLAGS_REG)
+	(eq:CCO (plus:<widerintmode>
+		   (sign_extend:<widerintmode>
+		      (match_operand:SWI 1 "nonimmediate_operand" "%0,0"))
+		   (sign_extend:<widerintmode>
+		      (match_operand:SWI 2 "<general_operand>" "<g>,<r><i>")))
+		(sign_extend:<widerintmode>
+		   (plus:SWI (match_dup 1) (match_dup 2)))))
+   (set (match_operand:SWI 0 "nonimmediate_operand" "=<r>,<r>m")
+	(plus:SWI (match_dup 1) (match_dup 2)))]
+  "ix86_binary_operator_ok (PLUS, <MODE>mode, operands)"
+  "add{<imodesuffix>}\t{%2, %0|%0, %2}"
+  [(set_attr "type" "alu")
+   (set_attr "mode" "<MODE>")])
+
 ;; The lea patterns for modes less than 32 bits need to be matched by
 ;; several insns converted to real lea by splitters.
 
@@ -6435,6 +6471,40 @@
   [(set_attr "type" "alu")
    (set_attr "mode" "SI")])
 
+;; Subtract with jump on overflow.
+(define_expand "subv<mode>4"
+  [(parallel [(set (reg:CCO FLAGS_REG)
+		   (eq:CCO (minus:<widerintmode>
+			      (sign_extend:<widerintmode>
+				 (match_operand:SWI 1 "register_operand"))
+			      (sign_extend:<widerintmode>
+				 (match_operand:SWI 2 "<general_operand>")))
+			   (sign_extend:<widerintmode>
+			      (minus:SWI (match_dup 1) (match_dup 2)))))
+	      (set (match_operand:SWI 0 "register_operand")
+		   (minus:SWI (match_dup 1) (match_dup 2)))])
+   (set (pc) (if_then_else
+	       (eq (reg:CCO FLAGS_REG) (const_int 0))
+	       (label_ref (match_operand 3))
+	       (pc)))]
+  "")
+
+(define_insn "*subv<mode>4"
+  [(set (reg:CCO FLAGS_REG)
+	(eq:CCO (minus:<widerintmode>
+		   (sign_extend:<widerintmode>
+		      (match_operand:SWI 1 "nonimmediate_operand" "0,0"))
+		   (sign_extend:<widerintmode>
+		      (match_operand:SWI 2 "<general_operand>" "<r><i>,<r>m")))
+		(sign_extend:<widerintmode>
+		   (minus:SWI (match_dup 1) (match_dup 2)))))
+   (set (match_operand:SWI 0 "nonimmediate_operand" "=<r>m,<r>")
+	(minus:SWI (match_dup 1) (match_dup 2)))]
+  "ix86_binary_operator_ok (MINUS, <MODE>mode, operands)"
+  "sub{<imodesuffix>}\t{%2, %0|%0, %2}"
+  [(set_attr "type" "alu")
+   (set_attr "mode" "<MODE>")])
+
 (define_insn "*sub<mode>_3"
   [(set (reg FLAGS_REG)
 	(compare (match_operand:SWI 1 "nonimmediate_operand" "0,0")
@@ -6749,6 +6819,59 @@
    (set_attr "bdver1_decode" "direct")
    (set_attr "mode" "QI")])
 
+;; Multiply with jump on overflow.
+(define_expand "mulv<mode>4"
+  [(parallel [(set (reg:CCO FLAGS_REG)
+		   (eq:CCO (mult:<widerintmode>
+			      (sign_extend:<widerintmode>
+				 (match_operand:SWI48 1 "register_operand"))
+			      (sign_extend:<widerintmode>
+				 (match_operand:SWI48 2 "<general_operand>")))
+			   (sign_extend:<widerintmode>
+			      (mult:SWI48 (match_dup 1) (match_dup 2)))))
+	      (set (match_operand:SWI48 0 "register_operand")
+		   (mult:SWI48 (match_dup 1) (match_dup 2)))])
+   (set (pc) (if_then_else
+	       (eq (reg:CCO FLAGS_REG) (const_int 0))
+	       (label_ref (match_operand 3))
+	       (pc)))]
+  "")
+
+(define_insn "*mulv<mode>4"
+  [(set (reg:CCO FLAGS_REG)
+	(eq:CCO (mult:<widerintmode>
+		   (sign_extend:<widerintmode>
+		      (match_operand:SWI 1 "nonimmediate_operand" "%rm,rm,0"))
+		   (sign_extend:<widerintmode>
+		      (match_operand:SWI 2 "<general_operand>" "K,<i>,mr")))
+		(sign_extend:<widerintmode>
+		   (mult:SWI (match_dup 1) (match_dup 2)))))
+   (set (match_operand:SWI 0 "register_operand" "=r,r,r")
+	(mult:SWI (match_dup 1) (match_dup 2)))]
+  "!(MEM_P (operands[1]) && MEM_P (operands[2]))"
+  "@
+   imul{<imodesuffix>}\t{%2, %1, %0|%0, %1, %2}
+   imul{<imodesuffix>}\t{%2, %1, %0|%0, %1, %2}
+   imul{<imodesuffix>}\t{%2, %0|%0, %2}"
+  [(set_attr "type" "imul")
+   (set_attr "prefix_0f" "0,0,1")
+   (set (attr "athlon_decode")
+	(cond [(eq_attr "cpu" "athlon")
+		  (const_string "vector")
+	       (eq_attr "alternative" "1")
+		  (const_string "vector")
+	       (and (eq_attr "alternative" "2")
+		    (match_operand 1 "memory_operand"))
+		  (const_string "vector")]
+	      (const_string "direct")))
+   (set (attr "amdfam10_decode")
+	(cond [(and (eq_attr "alternative" "0,1")
+		    (match_operand 1 "memory_operand"))
+		  (const_string "vector")]
+	      (const_string "direct")))
+   (set_attr "bdver1_decode" "direct")
+   (set_attr "mode" "<MODE>")])
+
 (define_expand "<u>mul<mode><dwi>3"
   [(parallel [(set (match_operand:<DWI> 0 "register_operand")
 		   (mult:<DWI>
@@ -8662,6 +8785,49 @@
   [(set_attr "type" "negnot")
    (set_attr "mode" "SI")])
 
+;; Negate with jump on overflow.
+(define_expand "negv<mode>3"
+  [(parallel [(set (reg:CCO FLAGS_REG)
+		   (ne:CCO (match_operand:SWI 1 "register_operand")
+			   (const_int 0)))
+	      (set (match_operand:SWI 0 "register_operand")
+		   (neg:SWI (match_dup 1)))])
+   (set (pc) (if_then_else
+	       (eq (reg:CCO FLAGS_REG) (const_int 0))
+	       (label_ref (match_operand 2))
+	       (pc)))]
+  ""
+{
+  rtx minv = GEN_INT (HOST_WIDE_INT_M1U
+		      << (GET_MODE_BITSIZE (<MODE>mode) - 1));
+  emit_insn (gen_negv<mode>3_1 (operands[0], operands[1], minv, operands[2]));
+  DONE;
+})
+
+(define_expand "negv<mode>3_1"
+  [(parallel [(set (reg:CCO FLAGS_REG)
+		   (ne:CCO (match_operand:SWI 1 "nonimmediate_operand")
+			   (match_operand:SWI 2 "const_int_operand")))
+	      (set (match_operand:SWI 0 "nonimmediate_operand")
+		   (neg:SWI (match_dup 1)))])
+   (set (pc) (if_then_else
+	       (eq (reg:CCO FLAGS_REG) (const_int 0))
+	       (label_ref (match_operand 3))
+	       (pc)))]
+  "")
+
+(define_insn "*negv<mode>3"
+  [(set (reg:CCO FLAGS_REG)
+	(ne:CCO (match_operand:SWI 1 "nonimmediate_operand" "0")
+		(match_operand:SWI 2 "const_int_operand")))
+   (set (match_operand:SWI 0 "nonimmediate_operand" "=<r>m")
+	(neg:SWI (match_dup 1)))]
+  "ix86_unary_operator_ok (NEG, <MODE>mode, operands)
+   && mode_signbit_p (<MODE>mode, operands[2])"
+  "neg{<imodesuffix>}\t%0"
+  [(set_attr "type" "negnot")
+   (set_attr "mode" "<MODE>")])
+
 ;; Changing of sign for FP values is doable using integer unit too.
 
 (define_expand "<code><mode>2"
--- gcc/c-family/c-gimplify.c.mp	2013-11-21 19:44:50.366036968 +0100
+++ gcc/c-family/c-gimplify.c	2013-11-22 01:10:27.725635249 +0100
@@ -194,7 +194,9 @@ c_gimplify_expr (tree *expr_p, gimple_se
 	tree type = TREE_TYPE (TREE_OPERAND (*expr_p, 0));
 	if (INTEGRAL_TYPE_P (type) && c_promoting_integer_type_p (type))
 	  {
-	    if (TYPE_OVERFLOW_UNDEFINED (type))
+	    if (TYPE_OVERFLOW_UNDEFINED (type)
+		|| ((flag_sanitize & SANITIZE_SI_OVERFLOW)
+		    && !TYPE_OVERFLOW_WRAPS (type)))
 	      type = unsigned_type_for (type);
 	    return gimplify_self_mod_expr (expr_p, pre_p, post_p, 1, type);
 	  }
--- gcc/sanitizer.def.mp	2013-11-21 14:08:55.030796725 +0100
+++ gcc/sanitizer.def	2013-11-21 17:45:38.701245878 +0100
@@ -305,3 +305,19 @@ DEF_SANITIZER_BUILTIN(BUILT_IN_UBSAN_HAN
 		      "__ubsan_handle_type_mismatch",
 		      BT_FN_VOID_PTR_PTR,
 		      ATTR_COLD_NOTHROW_LEAF_LIST)
+DEF_SANITIZER_BUILTIN(BUILT_IN_UBSAN_HANDLE_ADD_OVERFLOW,
+		      "__ubsan_handle_add_overflow",
+		      BT_FN_VOID_PTR_PTR_PTR,
+		      ATTR_COLD_NOTHROW_LEAF_LIST)
+DEF_SANITIZER_BUILTIN(BUILT_IN_UBSAN_HANDLE_SUB_OVERFLOW,
+		      "__ubsan_handle_sub_overflow",
+		      BT_FN_VOID_PTR_PTR_PTR,
+		      ATTR_COLD_NOTHROW_LEAF_LIST)
+DEF_SANITIZER_BUILTIN(BUILT_IN_UBSAN_HANDLE_MUL_OVERFLOW,
+		      "__ubsan_handle_mul_overflow",
+		      BT_FN_VOID_PTR_PTR_PTR,
+		      ATTR_COLD_NOTHROW_LEAF_LIST)
+DEF_SANITIZER_BUILTIN(BUILT_IN_UBSAN_HANDLE_NEGATE_OVERFLOW,
+		      "__ubsan_handle_negate_overflow",
+		      BT_FN_VOID_PTR_PTR,
+		      ATTR_COLD_NOTHROW_LEAF_LIST)
--- gcc/ubsan.h.mp	2013-11-21 14:08:55.032796733 +0100
+++ gcc/ubsan.h	2013-11-21 14:09:00.529816720 +0100
@@ -21,6 +21,12 @@ along with GCC; see the file COPYING3.
 #ifndef GCC_UBSAN_H
 #define GCC_UBSAN_H
 
+/* From predict.c.  */
+#define PROB_VERY_UNLIKELY	(REG_BR_PROB_BASE / 2000 - 1)
+#define PROB_EVEN		(REG_BR_PROB_BASE / 2)
+#define PROB_VERY_LIKELY	(REG_BR_PROB_BASE - PROB_VERY_UNLIKELY)
+#define PROB_ALWAYS		(REG_BR_PROB_BASE)
+
 /* The various kinds of NULL pointer checks.  */
 enum ubsan_null_ckind {
   UBSAN_LOAD_OF,
@@ -43,6 +49,7 @@ extern tree ubsan_create_data (const cha
 extern tree ubsan_type_descriptor (tree, bool);
 extern tree ubsan_encode_value (tree);
 extern bool is_ubsan_builtin_p (tree);
+extern tree ubsan_build_overflow_builtin (tree_code, location_t, tree, tree, tree);
 
 #endif  /* GCC_UBSAN_H  */
 
--- gcc/gimple-fold.c.mp	2013-11-21 14:22:39.227998786 +0100
+++ gcc/gimple-fold.c	2013-11-21 17:45:38.510245061 +0100
@@ -2654,8 +2654,30 @@ gimple_fold_stmt_to_constant_1 (gimple s
 	tree fn;
 
 	if (gimple_call_internal_p (stmt))
-	  /* No folding yet for these functions.  */
-	  return NULL_TREE;
+	  {
+	    enum tree_code subcode = ERROR_MARK;
+	    switch (gimple_call_internal_fn (stmt))
+	      {
+	      case IFN_UBSAN_CHECK_ADD: subcode = PLUS_EXPR; break;
+	      case IFN_UBSAN_CHECK_SUB: subcode = MINUS_EXPR; break;
+	      case IFN_UBSAN_CHECK_MUL: subcode = MULT_EXPR; break;
+	      default: return NULL_TREE;
+	      }
+	    tree op0 = (*valueize) (gimple_call_arg (stmt, 0));
+	    tree op1 = (*valueize) (gimple_call_arg (stmt, 1));
+
+	    if (TREE_CODE (op0) != INTEGER_CST
+		|| TREE_CODE (op1) != INTEGER_CST)
+	      return NULL_TREE;
+	    tree res = fold_binary_loc (loc, subcode,
+					TREE_TYPE (gimple_call_arg (stmt, 0)),
+					op0, op1);
+	    if (res
+		&& TREE_CODE (res) == INTEGER_CST
+		&& !TREE_OVERFLOW (res))
+	      return res;
+	    return NULL_TREE;
+	  }
 
 	fn = (*valueize) (gimple_call_fn (stmt));
 	if (TREE_CODE (fn) == ADDR_EXPR
--- gcc/ubsan.c.mp	2013-11-21 14:08:55.031796729 +0100
+++ gcc/ubsan.c	2013-11-22 09:57:48.499716221 +0100
@@ -39,9 +39,6 @@ along with GCC; see the file COPYING3.
 #include "ubsan.h"
 #include "c-family/c-common.h"
 
-/* From trans-mem.c.  */
-#define PROB_VERY_UNLIKELY      (REG_BR_PROB_BASE / 2000 - 1)
-
 /* Map from a tree to a VAR_DECL tree.  */
 
 struct GTY(()) tree_type_map {
@@ -628,6 +625,98 @@ instrument_null (tree *tp, int * /*walk_
   return NULL_TREE;
 }
 
+/* Build an ubsan builtin call for the signed-integer-overflow
+   sanitization.  CODE says what kind of builtin are we building,
+   LOC is a location, LHSTYPE is the type of LHS, OP0 and OP1
+   are operands of the binary operation.  */
+
+tree
+ubsan_build_overflow_builtin (tree_code code, location_t loc, tree lhstype,
+			      tree op0, tree op1)
+{
+  tree data = ubsan_create_data ("__ubsan_overflow_data", loc, NULL,
+				 ubsan_type_descriptor (lhstype, false),
+				 NULL_TREE);
+  enum built_in_function fn_code;
+
+  switch (code)
+    {
+    case PLUS_EXPR:
+      fn_code = BUILT_IN_UBSAN_HANDLE_ADD_OVERFLOW;
+      break;
+    case MINUS_EXPR:
+      fn_code = BUILT_IN_UBSAN_HANDLE_SUB_OVERFLOW;
+      break;
+    case MULT_EXPR:
+      fn_code = BUILT_IN_UBSAN_HANDLE_MUL_OVERFLOW;
+      break;
+    case NEGATE_EXPR:
+      fn_code = BUILT_IN_UBSAN_HANDLE_NEGATE_OVERFLOW;
+      break;
+    default:
+      gcc_unreachable ();
+    }
+  tree fn = builtin_decl_explicit (fn_code);
+  return build_call_expr_loc (loc, fn, 2 + (code != NEGATE_EXPR),
+			      build_fold_addr_expr_loc (loc, data),
+			      ubsan_encode_value (op0),
+			      op1 ? ubsan_encode_value (op1) : NULL_TREE);
+}
+
+/* Perform the signed integer instrumentation.  GSI is the iterator
+   pointing at statement we are trying to instrument.  */
+
+static void
+instrument_si_overflow (gimple_stmt_iterator gsi)
+{
+  gimple stmt = gsi_stmt (gsi);
+  tree_code code = gimple_assign_rhs_code (stmt);
+  tree lhs = gimple_assign_lhs (stmt);
+  tree lhstype = TREE_TYPE (lhs);
+  tree a, b;
+  gimple g;
+
+  /* If this is not a signed operation, don't instrument anything here.
+     Also punt on bit-fields.  */
+  if (!INTEGRAL_TYPE_P (lhstype)
+      || TYPE_OVERFLOW_WRAPS (lhstype)
+      || GET_MODE_BITSIZE (TYPE_MODE (lhstype)) != TYPE_PRECISION (lhstype))
+    return;
+
+  switch (code)
+    {
+    case MINUS_EXPR:
+    case PLUS_EXPR:
+    case MULT_EXPR:
+      /* Transform
+	 i = u {+,-,*} 5;
+	 into
+	 i = UBSAN_CHECK_{ADD,SUB,MUL} (u, 5);  */
+      a = gimple_assign_rhs1 (stmt);
+      b = gimple_assign_rhs2 (stmt);
+      g = gimple_build_call_internal (code == PLUS_EXPR
+				      ? IFN_UBSAN_CHECK_ADD
+				      : code == MINUS_EXPR
+				      ? IFN_UBSAN_CHECK_SUB
+				      : IFN_UBSAN_CHECK_MUL, 2, a, b);
+      gimple_call_set_lhs (g, lhs);
+      gsi_replace (&gsi, g, false);
+      break;
+    case NEGATE_EXPR:
+      /* Represent i = -u;
+	 as
+	 i = UBSAN_CHECK_SUB (0, u);  */
+      a = build_int_cst (lhstype, 0);
+      b = gimple_assign_rhs1 (stmt);
+      g = gimple_build_call_internal (IFN_UBSAN_CHECK_SUB, 2, a, b);
+      gimple_call_set_lhs (g, lhs);
+      gsi_replace (&gsi, g, false);
+      break;
+    default:
+      break;
+    }
+}
+
 /* Gate and execute functions for ubsan pass.  */
 
 static unsigned int
@@ -640,7 +729,6 @@ ubsan_pass (void)
     {
       for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi);)
 	{
-	  struct walk_stmt_info wi;
 	  gimple stmt = gsi_stmt (gsi);
 	  if (is_gimple_debug (stmt))
 	    {
@@ -648,9 +736,18 @@ ubsan_pass (void)
 	      continue;
 	    }
 
-	  memset (&wi, 0, sizeof (wi));
-	  wi.gsi = gsi;
-	  walk_gimple_op (stmt, instrument_null, &wi);
+	  if (flag_sanitize & SANITIZE_SI_OVERFLOW
+	      && is_gimple_assign (stmt))
+	    instrument_si_overflow (gsi);
+
+	  if (flag_sanitize & SANITIZE_NULL)
+	    {
+	      struct walk_stmt_info wi;
+	      memset (&wi, 0, sizeof (wi));
+	      wi.gsi = gsi;
+	      walk_gimple_op (stmt, instrument_null, &wi);
+	    }
+
 	  gsi_next (&gsi);
 	}
     }
@@ -660,7 +757,7 @@ ubsan_pass (void)
 static bool
 gate_ubsan (void)
 {
-  return flag_sanitize & SANITIZE_NULL;
+  return flag_sanitize & (SANITIZE_NULL | SANITIZE_SI_OVERFLOW);
 }
 
 namespace {
--- gcc/flag-types.h.mp	2013-11-21 14:08:55.026796709 +0100
+++ gcc/flag-types.h	2013-11-21 14:09:00.517816668 +0100
@@ -212,8 +212,9 @@ enum sanitize_code {
   SANITIZE_UNREACHABLE = 1 << 4,
   SANITIZE_VLA = 1 << 5,
   SANITIZE_NULL = 1 << 6,
+  SANITIZE_SI_OVERFLOW = 1 << 7,
   SANITIZE_UNDEFINED = SANITIZE_SHIFT | SANITIZE_DIVIDE | SANITIZE_UNREACHABLE
-		       | SANITIZE_VLA | SANITIZE_NULL
+		       | SANITIZE_VLA | SANITIZE_NULL | SANITIZE_SI_OVERFLOW
 };
 
 /* flag_vtable_verify initialization levels. */
--- gcc/internal-fn.c.mp	2013-11-21 14:08:55.027796713 +0100
+++ gcc/internal-fn.c	2013-11-22 10:04:19.796117746 +0100
@@ -26,6 +26,8 @@ along with GCC; see the file COPYING3.
 #include "expr.h"
 #include "optabs.h"
 #include "gimple.h"
+#include "ubsan.h"
+#include "target.h"
 
 /* The names of each internal function, indexed by function number.  */
 const char *const internal_fn_name_array[] = {
@@ -148,6 +150,300 @@ expand_UBSAN_NULL (gimple stmt ATTRIBUTE
   gcc_unreachable ();
 }
 
+/* Add sub/add overflow checking to the statement STMT.
+   CODE says whether the operation is +, or -.  */
+
+void
+ubsan_expand_si_overflow_addsub_check (tree_code code, gimple stmt)
+{
+  rtx res, op0, op1;
+  tree lhs, fn, arg0, arg1;
+  rtx done_label, do_error, target = NULL_RTX;
+
+  lhs = gimple_call_lhs (stmt);
+  arg0 = gimple_call_arg (stmt, 0);
+  arg1 = gimple_call_arg (stmt, 1);
+  done_label = gen_label_rtx ();
+  do_error = gen_label_rtx ();
+  fn = ubsan_build_overflow_builtin (code, gimple_location (stmt),
+				     TREE_TYPE (arg0), arg0, arg1);
+  op0 = expand_normal (arg0);
+  op1 = expand_normal (arg1);
+
+  enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg0));
+  if (lhs)
+    target = expand_expr (lhs, NULL_RTX, VOIDmode, EXPAND_WRITE);
+
+  enum insn_code icode
+    = optab_handler (code == PLUS_EXPR ? addv4_optab : subv4_optab, mode);
+  if (icode != CODE_FOR_nothing)
+    {
+      struct expand_operand ops[4];
+      rtx last = get_last_insn ();
+
+      res = gen_reg_rtx (mode);
+      create_output_operand (&ops[0], res, mode);
+      create_input_operand (&ops[1], op0, mode);
+      create_input_operand (&ops[2], op1, mode);
+      create_fixed_operand (&ops[3], do_error);
+      if (maybe_expand_insn (icode, 4, ops))
+	{
+	  last = get_last_insn ();
+	  if (profile_status != PROFILE_ABSENT
+	      && JUMP_P (last)
+	      && any_condjump_p (last)
+	      && !find_reg_note (last, REG_BR_PROB, 0))
+	    add_int_reg_note (last, REG_BR_PROB, PROB_VERY_UNLIKELY);
+	  emit_jump (done_label);
+        }
+      else
+	{
+	  delete_insns_since (last);
+	  icode = CODE_FOR_nothing;
+	}
+    }
+
+  if (icode == CODE_FOR_nothing)
+    {
+      rtx sub_check = gen_label_rtx ();
+
+      /* Compute the operation.  On RTL level, the addition is always
+	 unsigned.  */
+      res = expand_binop (mode, add_optab, op0, op1,
+			  NULL_RTX, false, OPTAB_LIB_WIDEN);
+
+      /* If the op1 is negative, we have to use a different check.  */
+      emit_cmp_and_jump_insns (op1, const0_rtx, LT, NULL_RTX, mode,
+			       false, sub_check, PROB_EVEN);
+
+      /* Compare the result of the addition with one of the operands.  */
+      emit_cmp_and_jump_insns (res, op0, code == PLUS_EXPR ? GE : LE,
+			       NULL_RTX, mode, false, done_label,
+			       PROB_VERY_LIKELY);
+      /* If we get here, we have to print the error.  */
+      emit_jump (do_error);
+
+      emit_label (sub_check);
+      /* We have k = a + b for b < 0 here.  k <= a must hold.  */
+      emit_cmp_and_jump_insns (res, op0, code == PLUS_EXPR ? LE : GE,
+			       NULL_RTX, mode, false, done_label,
+			       PROB_VERY_LIKELY);
+    }
+
+   emit_label (do_error);
+   /* Expand the ubsan builtin call.  */
+   expand_normal (fn);
+
+   /* We're done.  */
+   emit_label (done_label);
+
+  if (lhs)
+    emit_move_insn (target, res);
+}
+
+/* Add negate overflow checking to the statement STMT.  */
+
+void
+ubsan_expand_si_overflow_neg_check (gimple stmt)
+{
+  rtx res, op1;
+  tree lhs, fn, arg1;
+  rtx done_label, do_error, target = NULL_RTX;
+
+  lhs = gimple_call_lhs (stmt);
+  arg1 = gimple_call_arg (stmt, 1);
+  done_label = gen_label_rtx ();
+  do_error = gen_label_rtx ();
+  fn = ubsan_build_overflow_builtin (NEGATE_EXPR, gimple_location (stmt),
+				     TREE_TYPE (arg1), arg1, NULL_TREE);
+
+  op1 = expand_normal (arg1);
+
+  enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg1));
+  if (lhs)
+    target = expand_expr (lhs, NULL_RTX, VOIDmode, EXPAND_WRITE);
+
+  enum insn_code icode = optab_handler (negv3_optab, mode);
+  if (icode != CODE_FOR_nothing)
+    {
+      struct expand_operand ops[3];
+      rtx last = get_last_insn ();
+
+      res = gen_reg_rtx (mode);
+      create_output_operand (&ops[0], res, mode);
+      create_input_operand (&ops[1], op1, mode);
+      create_fixed_operand (&ops[2], do_error);
+      if (maybe_expand_insn (icode, 3, ops))
+	{
+	  last = get_last_insn ();
+	  if (profile_status != PROFILE_ABSENT
+	      && JUMP_P (last)
+	      && any_condjump_p (last)
+	      && !find_reg_note (last, REG_BR_PROB, 0))
+	    add_int_reg_note (last, REG_BR_PROB, PROB_VERY_UNLIKELY);
+	  emit_jump (done_label);
+	  res = target;
+        }
+      else
+	{
+	  delete_insns_since (last);
+	  icode = CODE_FOR_nothing;
+	}
+    }
+
+  if (icode == CODE_FOR_nothing)
+    {
+      /* Compute the operation.  On RTL level, the addition is always
+	 unsigned.  */
+      res = expand_unop (mode, neg_optab, op1, NULL_RTX, false);
+
+      /* Compare the operand with the most negative value.  */
+      rtx minv = expand_normal (TYPE_MIN_VALUE (TREE_TYPE (arg1)));
+      emit_cmp_and_jump_insns (op1, minv, NE, NULL_RTX, mode, false,
+			       done_label, PROB_VERY_LIKELY);
+    }
+
+  emit_label (do_error);
+  /* Expand the ubsan builtin call.  */
+  expand_normal (fn);
+
+  /* We're done.  */
+  emit_label (done_label);
+
+  if (lhs)
+    emit_move_insn (target, res);
+}
+
+/* Add mul overflow checking to the statement STMT.  */
+
+void
+ubsan_expand_si_overflow_mul_check (gimple stmt)
+{
+  rtx res, op0, op1;
+  tree lhs, fn, arg0, arg1;
+  rtx done_label, do_error, target = NULL_RTX;
+
+  lhs = gimple_call_lhs (stmt);
+  arg0 = gimple_call_arg (stmt, 0);
+  arg1 = gimple_call_arg (stmt, 1);
+  done_label = gen_label_rtx ();
+  do_error = gen_label_rtx ();
+  fn = ubsan_build_overflow_builtin (MULT_EXPR, gimple_location (stmt),
+				     TREE_TYPE (arg0), arg0, arg1);
+
+  op0 = expand_normal (arg0);
+  op1 = expand_normal (arg1);
+
+  enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg0));
+  if (lhs)
+    target = expand_expr (lhs, NULL_RTX, VOIDmode, EXPAND_WRITE);
+
+  enum insn_code icode = optab_handler (mulv4_optab, mode);
+  if (icode != CODE_FOR_nothing)
+    {
+      struct expand_operand ops[4];
+      rtx last = get_last_insn ();
+
+      res = gen_reg_rtx (mode);
+      create_output_operand (&ops[0], res, mode);
+      create_input_operand (&ops[1], op0, mode);
+      create_input_operand (&ops[2], op1, mode);
+      create_fixed_operand (&ops[3], do_error);
+      if (maybe_expand_insn (icode, 4, ops))
+	{
+	  last = get_last_insn ();
+	  if (profile_status != PROFILE_ABSENT
+	      && JUMP_P (last)
+	      && any_condjump_p (last)
+	      && !find_reg_note (last, REG_BR_PROB, 0))
+	    add_int_reg_note (last, REG_BR_PROB, PROB_VERY_UNLIKELY);
+	  emit_jump (done_label);
+        }
+      else
+	{
+	  delete_insns_since (last);
+	  icode = CODE_FOR_nothing;
+	}
+    }
+
+  if (icode == CODE_FOR_nothing)
+    {
+      struct separate_ops ops;
+      ops.op0 = arg0;
+      ops.op1 = arg1;
+      ops.op2 = NULL_TREE;
+      ops.location = gimple_location (stmt);
+      if (GET_MODE_2XWIDER_MODE (mode) != VOIDmode
+	  && targetm.scalar_mode_supported_p (GET_MODE_2XWIDER_MODE (mode)))
+	{
+	  enum machine_mode wmode = GET_MODE_2XWIDER_MODE (mode);
+	  ops.code = WIDEN_MULT_EXPR;
+	  ops.type
+	    = build_nonstandard_integer_type (GET_MODE_PRECISION (wmode), 0);
+
+	  res = expand_expr_real_2 (&ops, NULL_RTX, wmode, EXPAND_NORMAL);
+	  rtx hipart = expand_shift (RSHIFT_EXPR, wmode, res,
+				     GET_MODE_PRECISION (mode), NULL_RTX, 0);
+	  hipart = gen_lowpart (mode, hipart);
+	  res = gen_lowpart (mode, res);
+	  rtx signbit = expand_shift (RSHIFT_EXPR, mode, res,
+				      GET_MODE_PRECISION (mode) - 1,
+				      NULL_RTX, 0);
+	  /* RES is low half of the double width result, HIPART
+	     the high half.  There was overflow if
+	     HIPART is different from RES < 0 ? -1 : 0.  */
+	  emit_cmp_and_jump_insns (signbit, hipart, EQ, NULL_RTX, mode,
+				   false, done_label, PROB_VERY_LIKELY);
+	}
+      else
+	{
+	  /* For now we don't instrument this.  See __mulvDI3 in libgcc2.c
+	     for what could be done.  */
+	  ops.code = MULT_EXPR;
+	  ops.type = TREE_TYPE (arg0);
+	  res = expand_expr_real_2 (&ops, NULL_RTX, mode, EXPAND_NORMAL);
+	  emit_jump (done_label);
+	}
+    }
+
+  emit_label (do_error);
+  /* Expand the ubsan builtin call.  */
+  expand_normal (fn);
+
+  /* We're done.  */
+  emit_label (done_label);
+
+  if (lhs)
+    emit_move_insn (target, res);
+}
+
+/* Expand UBSAN_CHECK_ADD call STMT.  */
+
+static void
+expand_UBSAN_CHECK_ADD (gimple stmt)
+{
+  ubsan_expand_si_overflow_addsub_check (PLUS_EXPR, stmt);
+}
+
+/* Expand UBSAN_CHECK_SUB call STMT.  */
+
+static void
+expand_UBSAN_CHECK_SUB (gimple stmt)
+{
+  if (integer_zerop (gimple_call_arg (stmt, 0)))
+    ubsan_expand_si_overflow_neg_check (stmt);
+  else
+    ubsan_expand_si_overflow_addsub_check (MINUS_EXPR, stmt);
+}
+
+/* Expand UBSAN_CHECK_MUL call STMT.  */
+
+static void
+expand_UBSAN_CHECK_MUL (gimple stmt)
+{
+  ubsan_expand_si_overflow_mul_check (stmt);
+}
+
 /* Routines to expand each internal function, indexed by function number.
    Each routine has the prototype:
 
--- gcc/fold-const.c.mp	2013-11-21 14:22:49.239034849 +0100
+++ gcc/fold-const.c	2013-11-21 14:23:48.426249349 +0100
@@ -10330,14 +10330,16 @@ fold_binary_loc (location_t loc,
 
     case PLUS_EXPR:
       /* A + (-B) -> A - B */
-      if (TREE_CODE (arg1) == NEGATE_EXPR)
+      if (TREE_CODE (arg1) == NEGATE_EXPR
+	  && (flag_sanitize & SANITIZE_SI_OVERFLOW) == 0)
 	return fold_build2_loc (loc, MINUS_EXPR, type,
 			    fold_convert_loc (loc, type, arg0),
 			    fold_convert_loc (loc, type,
 					      TREE_OPERAND (arg1, 0)));
       /* (-A) + B -> B - A */
       if (TREE_CODE (arg0) == NEGATE_EXPR
-	  && reorder_operands_p (TREE_OPERAND (arg0, 0), arg1))
+	  && reorder_operands_p (TREE_OPERAND (arg0, 0), arg1)
+	  && (flag_sanitize & SANITIZE_SI_OVERFLOW) == 0)
 	return fold_build2_loc (loc, MINUS_EXPR, type,
 			    fold_convert_loc (loc, type, arg1),
 			    fold_convert_loc (loc, type,
--- gcc/internal-fn.def.mp	2013-11-21 14:08:55.028796717 +0100
+++ gcc/internal-fn.def	2013-11-21 17:45:38.703245887 +0100
@@ -45,3 +45,6 @@ DEF_INTERNAL_FN (GOMP_SIMD_VF, ECF_CONST
 DEF_INTERNAL_FN (GOMP_SIMD_LAST_LANE, ECF_CONST | ECF_LEAF | ECF_NOTHROW)
 DEF_INTERNAL_FN (ANNOTATE,  ECF_CONST | ECF_LEAF | ECF_NOTHROW)
 DEF_INTERNAL_FN (UBSAN_NULL, ECF_LEAF | ECF_NOTHROW)
+DEF_INTERNAL_FN (UBSAN_CHECK_ADD, ECF_CONST | ECF_LEAF | ECF_NOTHROW)
+DEF_INTERNAL_FN (UBSAN_CHECK_SUB, ECF_CONST | ECF_LEAF | ECF_NOTHROW)
+DEF_INTERNAL_FN (UBSAN_CHECK_MUL, ECF_CONST | ECF_LEAF | ECF_NOTHROW)
--- gcc/tree-vrp.c.mp	2013-11-21 14:22:35.167984172 +0100
+++ gcc/tree-vrp.c	2013-11-21 17:45:38.595245432 +0100
@@ -3748,6 +3748,40 @@ extract_range_basic (value_range_t *vr,
 	  break;
 	}
     }
+  else if (is_gimple_call (stmt)
+	   && gimple_call_internal_p (stmt))
+    {
+      enum tree_code subcode = ERROR_MARK;
+      switch (gimple_call_internal_fn (stmt))
+	{
+	case IFN_UBSAN_CHECK_ADD: subcode = PLUS_EXPR; break;
+	case IFN_UBSAN_CHECK_SUB: subcode = MINUS_EXPR; break;
+	case IFN_UBSAN_CHECK_MUL: subcode = MULT_EXPR; break;
+	default: break;
+	}
+      if (subcode != ERROR_MARK)
+	{
+	  bool saved_flag_wrapv = flag_wrapv;
+	  /* Pretend the arithmetics is wrapping.  If there is
+	     any overflow, we'll complain, but will actually do
+	     wrapping operation.  */
+	  flag_wrapv = 1;
+	  extract_range_from_binary_expr (vr, subcode, type,
+					  gimple_call_arg (stmt, 0),
+					  gimple_call_arg (stmt, 1));
+	  flag_wrapv = saved_flag_wrapv;
+
+	  /* If for both arguments vrp_valueize returned non-NULL,
+	     this should have been already folded and if not, it
+	     wasn't folded because of overflow.  Avoid removing the
+	     UBSAN_CHECK_* calls in that case.  */
+	  if (vr->type == VR_RANGE
+	      && (vr->min == vr->max
+		  || operand_equal_p (vr->min, vr->max, 0)))
+	    set_value_range_to_varying (vr);
+	  return;
+	}
+    }
   if (INTEGRAL_TYPE_P (type)
       && gimple_stmt_nonnegative_warnv_p (stmt, &sop))
     set_value_range_to_nonnegative (vr, type,
--- gcc/testsuite/c-c++-common/ubsan/overflow-mul-2.c.mp	2013-11-22 00:58:49.911784181 +0100
+++ gcc/testsuite/c-c++-common/ubsan/overflow-mul-2.c	2013-11-22 01:35:31.796587252 +0100
@@ -0,0 +1,27 @@
+/* { dg-do run } */
+/* { dg-options "-fsanitize=signed-integer-overflow -Wno-unused-variable" } */
+/* { dg-skip-if "" { *-*-* } { "-flto" } { "" } } */
+
+#define INT_MAX __INT_MAX__
+#define LONG_MAX __LONG_MAX__
+
+int
+main (void)
+{
+  volatile int j = INT_MAX;
+  volatile int i = 2;
+  volatile int k = j * i;
+  k = i * j;
+
+  volatile long int m = LONG_MAX;
+  volatile long int n = 2;
+  volatile long int o = m * n;
+  o = n * m;
+
+  return 0;
+}
+
+/* { dg-output "signed integer overflow: 2147483647 \\* 2 cannot be represented in type 'int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: 2 \\* 2147483647 cannot be represented in type 'int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: \[^\n\r]* \\* 2 cannot be represented in type 'long int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: 2 \\* \[^\n\r]* cannot be represented in type 'long int'(\n|\r\n|\r)" } */
--- gcc/testsuite/c-c++-common/ubsan/overflow-add-1.c.mp	2013-11-21 14:36:31.997032821 +0100
+++ gcc/testsuite/c-c++-common/ubsan/overflow-add-1.c	2013-11-21 21:01:38.356269474 +0100
@@ -0,0 +1,64 @@
+/* { dg-do run } */
+/* { dg-options "-fsanitize=signed-integer-overflow -Wno-unused-variable" } */
+/* { dg-skip-if "" { *-*-* } { "-flto" } { "" } } */
+/* { dg-skip-if "" { *-*-* }  { "-Os" } { "" } } */
+
+// TODO: This is miscompiled with -Os!
+
+#define SCHAR_MAX __SCHAR_MAX__
+#define SHRT_MAX __SHRT_MAX__
+#define INT_MAX __INT_MAX__
+#define INT_MIN (-__INT_MAX__ - 1)
+
+void __attribute__((noinline,noclone))
+check (int i, int j)
+{
+  if (i != j)
+    __builtin_abort ();
+}
+
+int
+main (void)
+{
+#if __INT_MAX__ == 2147483647
+  /* Here, nothing should fail.  */
+  volatile int j = INT_MAX;
+  volatile int i = -1;
+  volatile int k = j + i;
+  check (k, 2147483646);
+  k = i + j;
+  check (k, 2147483646);
+  j--;
+  check (j, 2147483646);
+
+  i = 1;
+  j = INT_MIN;
+  k = i + j;
+  check (k, -2147483647);
+  k = j + i;
+  check (k, -2147483647);
+  j++;
+  check (j, -2147483647);
+#endif
+
+  /* Test integer promotion.  */
+#if __SCHAR_MAX__ == 127
+  volatile signed char a = SCHAR_MAX;
+  volatile signed char b = 1;
+  volatile signed char c = a + b;
+  check (c, -128);
+  a++;
+  check (a, -128);
+#endif
+
+#if __SHRT_MAX__ == 32767
+  volatile short d = SHRT_MAX;
+  volatile short e = 1;
+  volatile short f = d + e;
+  check (f, -32768);
+  d++;
+  check (d, -32768);
+#endif
+
+  return 0;
+}
--- gcc/testsuite/c-c++-common/ubsan/overflow-add-2.c.mp	2013-11-21 15:20:22.148184380 +0100
+++ gcc/testsuite/c-c++-common/ubsan/overflow-add-2.c	2013-11-21 18:11:09.883041430 +0100
@@ -0,0 +1,61 @@
+/* { dg-do run } */
+/* { dg-options "-fsanitize=signed-integer-overflow -Wno-unused-variable" } */
+/* { dg-skip-if "" { *-*-* } { "-flto" } { "" } } */
+
+#define INT_MAX __INT_MAX__
+#define INT_MIN (-__INT_MAX__ - 1)
+#define LONG_MAX __LONG_MAX__
+#define LONG_MIN (-__LONG_MAX__ - 1L)
+#define LLONG_MAX __LONG_LONG_MAX__
+#define LLONG_MIN (-__LONG_LONG_MAX__ - 1L)
+
+int
+main (void)
+{
+  volatile int j = INT_MAX;
+  volatile int i = 1;
+  volatile int k = j + i;
+  k = i + j;
+  j++;
+  j = INT_MAX - 100;
+  j += (1 << 10);
+
+  j = INT_MIN;
+  i = -1;
+  k = i + j;
+  k = j + i;
+  j = INT_MIN + 100;
+  j += -(1 << 10);
+
+  volatile long int m = LONG_MAX;
+  volatile long int n = 1;
+  volatile long int o = m + n;
+  o = n + m;
+  m++;
+  m = LONG_MAX - 100;
+  m += (1 << 10);
+
+  m = LONG_MIN;
+  n = -1;
+  o = m + n;
+  o = n + m;
+  m = LONG_MIN + 100;
+  m += -(1 << 10);
+
+  return 0;
+}
+
+/* { dg-output "signed integer overflow: 2147483647 \\+ 1 cannot be represented in type 'int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: 1 \\+ 2147483647 cannot be represented in type 'int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: 2147483647 \\+ 1 cannot be represented in type 'int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: 2147483547 \\+ 1024 cannot be represented in type 'int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -1 \\+ -2147483648 cannot be represented in type 'int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -2147483648 \\+ -1 cannot be represented in type 'int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -2147483548 \\+ -1024 cannot be represented in type 'int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: \[^\n\r]* \\+ 1 cannot be represented in type 'long int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: 1 \\+ \[^\n\r]* cannot be represented in type 'long int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: \[^\n\r]* \\+ 1 cannot be represented in type 'long int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: \[^\n\r]* \\+ 1024 cannot be represented in type 'long int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -\[^\n\r]* \\+ -1 cannot be represented in type 'long int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -1 \\+ -\[^\n\r]* cannot be represented in type 'long int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -\[^\n\r]* \\+ -1024 cannot be represented in type 'long int'(\n|\r\n|\r)" } */
--- gcc/testsuite/c-c++-common/ubsan/overflow-mul-1.c.mp	2013-11-21 23:57:24.320188104 +0100
+++ gcc/testsuite/c-c++-common/ubsan/overflow-mul-1.c	2013-11-22 01:36:27.662805713 +0100
@@ -0,0 +1,50 @@
+/* { dg-do run } */
+/* { dg-options "-fsanitize=signed-integer-overflow -Wno-unused-variable" } */
+/* { dg-skip-if "" { *-*-* } { "-flto" } { "" } } */
+/* { dg-skip-if "" { *-*-* }  { "-Os" } { "" } } */
+
+// TODO: This is miscompiled with -Os!
+
+#define SCHAR_MAX __SCHAR_MAX__
+#define SHRT_MAX __SHRT_MAX__
+#define INT_MAX __INT_MAX__
+#define INT_MIN (-__INT_MAX__ - 1)
+
+void __attribute__((noinline,noclone))
+check (int i, int j)
+{
+  if (i != j)
+    __builtin_abort ();
+}
+
+int
+main (void)
+{
+  /* Test integer promotion.  */
+#if __SCHAR_MAX__ == 127
+  volatile signed char a = -2;
+  volatile signed char b = SCHAR_MAX;
+  volatile signed char c = a * b;
+  check (c, 2);
+#endif
+
+#if __SHRT_MAX__ == 32767
+  volatile short d = SHRT_MAX;
+  volatile short e = 2;
+  volatile short f = d * e;
+  check (f, -2);
+#endif
+
+#if __INT_MAX__ == 2147483647
+  volatile int m = INT_MAX;
+  volatile int n = 1;
+  volatile int o = m * n;
+  check (o, INT_MAX);
+
+  m = INT_MIN;
+  o = m * n;
+  check (o, INT_MIN);
+#endif
+
+  return 0;
+}
--- gcc/testsuite/c-c++-common/ubsan/overflow-sub-1.c.mp	2013-11-21 18:11:45.957184230 +0100
+++ gcc/testsuite/c-c++-common/ubsan/overflow-sub-1.c	2013-11-21 21:13:49.582029454 +0100
@@ -0,0 +1,66 @@
+/* { dg-do run } */
+/* { dg-options "-fsanitize=signed-integer-overflow -Wno-unused-variable" } */
+/* { dg-skip-if "" { *-*-* } { "-flto" } { "" } } */
+/* { dg-skip-if "" { *-*-* }  { "-Os" } { "" } } */
+
+// TODO: This is miscompiled with -Os!
+
+#define SCHAR_MAX __SCHAR_MAX__
+#define SCHAR_MIN (-__SCHAR_MAX__ - 1)
+#define SHRT_MAX __SHRT_MAX__
+#define SHRT_MIN (-__SHRT_MAX__ - 1)
+#define INT_MAX __INT_MAX__
+#define INT_MIN (-__INT_MAX__ - 1)
+
+void __attribute__((noinline,noclone))
+check (int i, int j)
+{
+  if (i != j)
+    __builtin_abort ();
+}
+
+int
+main (void)
+{
+#if __INT_MAX__ == 2147483647
+  /* Here, nothing should fail.  */
+  volatile int i = -1;
+  volatile int j = INT_MIN;
+  volatile int k = j - i;
+  check (k, -2147483647);
+  k = i - j;
+  check (k, 2147483647);
+  j++;
+  check (j, -2147483647);
+
+  i = 1;
+  j = INT_MAX;
+  k = i - j;
+  check (k, -2147483646);
+  k = j - i;
+  check (k, 2147483646);
+  j--;
+  check (k, 2147483646);
+#endif
+
+  /* Test integer promotion.  */
+#if __SCHAR_MAX__ == 127
+  volatile signed char a = SCHAR_MIN;
+  volatile signed char b = 1;
+  volatile signed char c = a - b;
+  check (c, 127);
+  a--;
+  check (a, 127);
+#endif
+
+#if __SHRT_MAX__ == 32767
+  volatile short d = SHRT_MIN;
+  volatile short e = 1;
+  volatile short f = d - e;
+  check (f, 32767);
+  d--;
+  check (d, 32767);
+#endif
+
+  return 0;
+}
--- gcc/testsuite/c-c++-common/ubsan/overflow-sub-2.c.mp	2013-11-21 18:16:18.730175229 +0100
+++ gcc/testsuite/c-c++-common/ubsan/overflow-sub-2.c	2013-11-21 18:48:29.099778507 +0100
@@ -0,0 +1,55 @@
+/* { dg-do run } */
+/* { dg-options "-fsanitize=signed-integer-overflow -Wno-unused-variable" } */
+/* { dg-skip-if "" { *-*-* } { "-flto" } { "" } } */
+
+#define INT_MAX __INT_MAX__
+#define INT_MIN (-__INT_MAX__ - 1)
+#define LONG_MAX __LONG_MAX__
+#define LONG_MIN (-__LONG_MAX__ - 1L)
+#define LLONG_MAX __LONG_LONG_MAX__
+#define LLONG_MIN (-__LONG_LONG_MAX__ - 1L)
+
+int
+main (void)
+{
+  volatile int j = INT_MIN;
+  volatile int i = 1;
+  volatile int k = j - i;
+  j--;
+  j = INT_MIN + 100;
+  j -= (1 << 10);
+
+  j = INT_MIN;
+  i = -1;
+  k = j - -i;
+
+  i = INT_MIN + 1000;
+  i -= (1 << 20);
+
+  volatile long int l = LONG_MIN;
+  volatile long int m = 1;
+  volatile long int n = l - m;
+  l--;
+  l = LONG_MIN + 100;
+  l -= (1 << 10);
+
+  l = LONG_MIN;
+  m = -1;
+  n = l - -m;
+
+  m = LONG_MIN + 1000;
+  m -= (1 << 20);
+
+  return 0;
+}
+
+/* { dg-output "signed integer overflow: -2147483648 - 1 cannot be represented in type 'int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -2147483648 \\+ -1 cannot be represented in type 'int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -2147483548 \\+ -1024 cannot be represented in type 'int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -2147483648 \\+ -1 cannot be represented in type 'int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -2147482648 \\+ -1048576 cannot be represented in type 'int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -\[^\n\r]* - 1 cannot be represented in type 'long int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -\[^\n\r]* \\+ -1 cannot be represented in type 'long int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -\[^\n\r]* \\+ -1024 cannot be represented in type 'long int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -\[^\n\r]* \\+ -1 cannot be represented in type 'long int'(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*signed integer overflow: -\[^\n\r]* \\+ -1048576 cannot be represented in type 'long int'(\n|\r\n|\r)" } */
--- gcc/testsuite/c-c++-common/ubsan/overflow-negate-1.c.mp	2013-11-22 01:44:01.284928783 +0100
+++ gcc/testsuite/c-c++-common/ubsan/overflow-negate-1.c	2013-11-22 01:45:21.526246391 +0100
@@ -0,0 +1,14 @@
+/* { dg-do run { target int128 } } */
+/* { dg-options "-fsanitize=signed-integer-overflow -Wno-unused-variable" } */
+/* { dg-skip-if "" { *-*-* } { "-flto" } { "" } } */
+
+#define INT_MIN (-__INT_MAX__ - 1)
+
+int
+main (void)
+{
+  int j = INT_MIN;
+  return -j;
+}
+
+/* { dg-output "negation of -2147483648 cannot be represented in type 'int'; cast to an unsigned type to negate this value to itself(\n|\r\n|\r)" } */
--- gcc/optabs.def.mp	2013-11-21 14:22:44.109016365 +0100
+++ gcc/optabs.def	2013-11-21 17:45:38.692245840 +0100
@@ -187,6 +187,10 @@ OPTAB_D (movcc_optab, "mov$acc")
 OPTAB_D (cmov_optab, "cmov$a6")
 OPTAB_D (cstore_optab, "cstore$a4")
 OPTAB_D (ctrap_optab, "ctrap$a4")
+OPTAB_D (addv4_optab, "addv$I$a4")
+OPTAB_D (subv4_optab, "subv$I$a4")
+OPTAB_D (mulv4_optab, "mulv$I$a4")
+OPTAB_D (negv3_optab, "negv$I$a3")
 
 OPTAB_D (smul_highpart_optab, "smul$a3_highpart")
 OPTAB_D (umul_highpart_optab, "umul$a3_highpart")
