Daily bump.

[platform/upstream/gcc.git] / gcc / c / c-fold.c

diff --git a/gcc/c/c-fold.c b/gcc/c/c-fold.c
index a4ece88..0ebcb46 100644 (file)
--- a/gcc/c/c-fold.c
+++ b/gcc/c/c-fold.c
@@ -1,5 +1,5 @@
 /* Support for fully folding sub-trees of an expression for C compiler.
-   Copyright (C) 1992-2019 Free Software Foundation, Inc.
+   Copyright (C) 1992-2021 Free Software Foundation, Inc.
 
 This file is part of GCC.
 
@@ -154,7 +154,7 @@ c_fully_fold_internal (tree expr, bool in_init, bool *maybe_const_operands,
   tree orig_op0, orig_op1, orig_op2;
   bool op0_const = true, op1_const = true, op2_const = true;
   bool op0_const_self = true, op1_const_self = true, op2_const_self = true;
-  bool nowarning = TREE_NO_WARNING (expr);
+  bool nowarning = warning_suppressed_p (expr, OPT_Woverflow);
   bool unused_p;
   bool op0_lval = false;
   source_range old_range;
@@ -346,6 +346,7 @@ c_fully_fold_internal (tree expr, bool in_init, bool *maybe_const_operands,
     case UNGT_EXPR:
     case UNGE_EXPR:
     case UNEQ_EXPR:
+    case MEM_REF:
       /* Binary operations evaluating both arguments (increment and
         decrement are binary internally in GCC).  */
       orig_op0 = op0 = TREE_OPERAND (expr, 0);
@@ -373,6 +374,7 @@ c_fully_fold_internal (tree expr, bool in_init, bool *maybe_const_operands,
        ret = fold (expr);
       if (TREE_OVERFLOW_P (ret)
          && !TREE_OVERFLOW_P (op0)
+         && !(BINARY_CLASS_P (op0) && TREE_OVERFLOW_P (TREE_OPERAND (op0, 1)))
          && !TREE_OVERFLOW_P (op1))
        overflow_warning (EXPR_LOC_OR_LOC (expr, input_location), ret, expr);
       if (code == LSHIFT_EXPR
@@ -435,6 +437,14 @@ c_fully_fold_internal (tree expr, bool in_init, bool *maybe_const_operands,
              || TREE_CODE (TREE_TYPE (orig_op0)) == FIXED_POINT_TYPE)
          && TREE_CODE (TREE_TYPE (orig_op1)) == INTEGER_TYPE)
        warn_for_div_by_zero (loc, op1);
+      if (code == MEM_REF
+         && ret != expr
+         && TREE_CODE (ret) == MEM_REF)
+       {
+         TREE_READONLY (ret) = TREE_READONLY (expr);
+         TREE_SIDE_EFFECTS (ret) = TREE_SIDE_EFFECTS (expr);
+         TREE_THIS_VOLATILE (ret) = TREE_THIS_VOLATILE (expr);
+       }
       goto out;
 
     case ADDR_EXPR:
@@ -660,13 +670,13 @@ c_fully_fold_internal (tree expr, bool in_init, bool *maybe_const_operands,
  out:
   /* Some folding may introduce NON_LVALUE_EXPRs; all lvalue checks
      have been done by this point, so remove them again.  */
-  nowarning |= TREE_NO_WARNING (ret);
+  nowarning |= warning_suppressed_p (ret, OPT_Woverflow);
   STRIP_TYPE_NOPS (ret);
-  if (nowarning && !TREE_NO_WARNING (ret))
+  if (nowarning && !warning_suppressed_p (ret, OPT_Woverflow))
     {
       if (!CAN_HAVE_LOCATION_P (ret))
        ret = build1 (NOP_EXPR, TREE_TYPE (ret), ret);
-      TREE_NO_WARNING (ret) = 1;
+      suppress_warning (ret, OPT_Woverflow);
     }
   if (ret != expr)
     {