2013-12-11 Bernd Edlinger <bernd.edlinger@hotmail.de>

        * expr.c (expand_assignment): Remove dependency on
        flag_strict_volatile_bitfields. Always set the memory
        access mode.
        (expand_expr_real_1): Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@205899 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 633aa92..13702fe 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,12 @@
 2013-12-11  Bernd Edlinger  <bernd.edlinger@hotmail.de>
 
+       * expr.c (expand_assignment): Remove dependency on
+       flag_strict_volatile_bitfields. Always set the memory 
+       access mode.
+       (expand_expr_real_1): Likewise.
+
+2013-12-11  Bernd Edlinger  <bernd.edlinger@hotmail.de>
+
        PR middle-end/59134
        * expmed.c (store_bit_field): Use narrow_bit_field_mem and
        store_fixed_bit_field_1 for -fstrict-volatile-bitfields.

diff --git a/gcc/expr.c b/gcc/expr.c
index 225555e..cde0b85 100644 (file)
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -4838,13 +4838,13 @@ expand_assignment (tree to, tree from, bool nontemporal)
 
       to_rtx = expand_expr (tem, NULL_RTX, VOIDmode, EXPAND_WRITE);
 
-      /* If the bitfield is volatile, we want to access it in the
+      /* If the field has a mode, we want to access it in the
         field's mode, not the computed mode.
         If a MEM has VOIDmode (external with incomplete type),
         use BLKmode for it instead.  */
       if (MEM_P (to_rtx))
        {
-         if (volatilep && flag_strict_volatile_bitfields > 0)
+         if (mode1 != VOIDmode)
            to_rtx = adjust_address (to_rtx, mode1, 0);
          else if (GET_MODE (to_rtx) == VOIDmode)
            to_rtx = adjust_address (to_rtx, BLKmode, 0);
@@ -9970,13 +9970,13 @@ expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode,
                         VOIDmode,
                         modifier == EXPAND_SUM ? EXPAND_NORMAL : modifier);
 
-       /* If the bitfield is volatile, we want to access it in the
+       /* If the field has a mode, we want to access it in the
           field's mode, not the computed mode.
           If a MEM has VOIDmode (external with incomplete type),
           use BLKmode for it instead.  */
        if (MEM_P (op0))
          {
-           if (volatilep && flag_strict_volatile_bitfields > 0)
+           if (mode1 != VOIDmode)
              op0 = adjust_address (op0, mode1, 0);
            else if (GET_MODE (op0) == VOIDmode)
              op0 = adjust_address (op0, BLKmode, 0);
@@ -10108,17 +10108,13 @@ expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode,
                && modifier != EXPAND_CONST_ADDRESS
                && modifier != EXPAND_INITIALIZER
                && modifier != EXPAND_MEMORY)
-           /* If the field is volatile, we always want an aligned
-              access.  Do this in following two situations:
-              1. the access is not already naturally
-              aligned, otherwise "normal" (non-bitfield) volatile fields
-              become non-addressable.
-              2. the bitsize is narrower than the access size. Need
-              to extract bitfields from the access.  */
-           || (volatilep && flag_strict_volatile_bitfields > 0
-               && (bitpos % GET_MODE_ALIGNMENT (mode) != 0 
-                   || (mode1 != BLKmode
-                       && bitsize < GET_MODE_SIZE (mode1) * BITS_PER_UNIT)))
+           /* If the bitfield is volatile and the bitsize
+              is narrower than the access size of the bitfield,
+              we need to extract bitfields from the access.  */
+           || (volatilep && TREE_CODE (exp) == COMPONENT_REF
+               && DECL_BIT_FIELD_TYPE (TREE_OPERAND (exp, 1))
+               && mode1 != BLKmode
+               && bitsize < GET_MODE_SIZE (mode1) * BITS_PER_UNIT)
            /* If the field isn't aligned enough to fetch as a memref,
               fetch it as a bit field.  */
            || (mode1 != BLKmode