Merge ubsan into trunk.

[thirdparty/gcc.git] / gcc / cp / typeck.c

diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index e09c325d51bac4c262221f866659c19212dfedf1..b4abbc56d5e23fcf0be6c553c187b6e050cb8c7a 100644 (file)
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -37,6 +37,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "convert.h"
 #include "c-family/c-common.h"
 #include "c-family/c-objc.h"
+#include "c-family/c-ubsan.h"
 #include "params.h"
 
 static tree pfn_from_ptrmemfunc (tree);
@@ -3882,6 +3883,7 @@ cp_build_binary_op (location_t location,
   tree final_type = 0;
 
   tree result;
+  tree orig_type = NULL;
 
   /* Nonzero if this is an operation like MIN or MAX which can
      safely be computed in short if both args are promoted shorts.
@@ -3906,6 +3908,15 @@ cp_build_binary_op (location_t location,
   op0 = orig_op0;
   op1 = orig_op1;
 
+  /* Remember whether we're doing / or %.  */
+  bool doing_div_or_mod = false;
+
+  /* Remember whether we're doing << or >>.  */
+  bool doing_shift = false;
+
+  /* Tree holding instrumentation expression.  */
+  tree instrument_expr = NULL;
+
   if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
       || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
       || code == TRUTH_XOR_EXPR)
@@ -4086,8 +4097,12 @@ cp_build_binary_op (location_t location,
        {
          enum tree_code tcode0 = code0, tcode1 = code1;
          tree cop1 = fold_non_dependent_expr_sfinae (op1, tf_none);
+         cop1 = maybe_constant_value (cop1);
 
-         warn_for_div_by_zero (location, maybe_constant_value (cop1));
+         if (tcode0 == INTEGER_TYPE)
+           doing_div_or_mod = true;
+
+         warn_for_div_by_zero (location, cop1);
 
          if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE)
            tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
@@ -4125,8 +4140,11 @@ cp_build_binary_op (location_t location,
     case FLOOR_MOD_EXPR:
       {
        tree cop1 = fold_non_dependent_expr_sfinae (op1, tf_none);
+       cop1 = maybe_constant_value (cop1);
 
-       warn_for_div_by_zero (location, maybe_constant_value (cop1));
+       if (code0 == INTEGER_TYPE)
+         doing_div_or_mod = true;
+       warn_for_div_by_zero (location, cop1);
       }
 
       if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
@@ -4180,6 +4198,7 @@ cp_build_binary_op (location_t location,
          if (TREE_CODE (const_op1) != INTEGER_CST)
            const_op1 = op1;
          result_type = type0;
+         doing_shift = true;
          if (TREE_CODE (const_op1) == INTEGER_CST)
            {
              if (tree_int_cst_lt (const_op1, integer_zero_node))
@@ -4227,6 +4246,7 @@ cp_build_binary_op (location_t location,
          if (TREE_CODE (const_op1) != INTEGER_CST)
            const_op1 = op1;
          result_type = type0;
+         doing_shift = true;
          if (TREE_CODE (const_op1) == INTEGER_CST)
            {
              if (tree_int_cst_lt (const_op1, integer_zero_node))
@@ -4796,8 +4816,9 @@ cp_build_binary_op (location_t location,
 
       if (shorten && none_complex)
        {
+         orig_type = result_type;
          final_type = result_type;
-         result_type = shorten_binary_op (result_type, op0, op1, 
+         result_type = shorten_binary_op (result_type, op0, op1,
                                           shorten == -1);
        }
 
@@ -4863,6 +4884,36 @@ cp_build_binary_op (location_t location,
   if (build_type == NULL_TREE)
     build_type = result_type;
 
+  if ((flag_sanitize & SANITIZE_UNDEFINED)
+      && !processing_template_decl
+      && current_function_decl != 0
+      && (doing_div_or_mod || doing_shift))
+    {
+      /* OP0 and/or OP1 might have side-effects.  */
+      op0 = cp_save_expr (op0);
+      op1 = cp_save_expr (op1);
+      op0 = maybe_constant_value (fold_non_dependent_expr_sfinae (op0,
+                                                                 tf_none));
+      op1 = maybe_constant_value (fold_non_dependent_expr_sfinae (op1,
+                                                                 tf_none));
+      if (doing_div_or_mod)
+       {
+         /* For diagnostics we want to use the promoted types without
+            shorten_binary_op.  So convert the arguments to the
+            original result_type.  */
+         tree cop0 = op0;
+         tree cop1 = op1;
+         if (orig_type != NULL && result_type != orig_type)
+           {
+             cop0 = cp_convert (orig_type, op0, complain);
+             cop1 = cp_convert (orig_type, op1, complain);
+           }
+         instrument_expr = ubsan_instrument_division (location, cop0, cop1);
+       }
+      else if (doing_shift)
+       instrument_expr = ubsan_instrument_shift (location, code, op0, op1);
+    }
+
   result = build2 (resultcode, build_type, op0, op1);
   result = fold_if_not_in_template (result);
   if (final_type != 0)
@@ -4873,6 +4924,10 @@ cp_build_binary_op (location_t location,
       && !TREE_OVERFLOW_P (op1))
     overflow_warning (location, result);
 
+  if ((flag_sanitize & SANITIZE_UNDEFINED) && instrument_expr != NULL)
+    result = fold_build2 (COMPOUND_EXPR, TREE_TYPE (result),
+                         instrument_expr, result);
+
   return result;
 }