(store_field): Test STRICT_ALIGNMENT at run time.

(expand_expr, COMPONENT_REF case): Fetch unaligned field as bitfield.

From-SVN: r4841

diff --git a/gcc/expr.c b/gcc/expr.c
index f8cb7b42b81756e435c0b3c44628f1bed1350ba8..4c6e84a6455483edd2b355d4459ed43e560db3b1 100644 (file)
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -2702,13 +2702,11 @@ store_field (target, bitsize, bitpos, mode, exp, value_mode,
       || (mode != BLKmode && ! direct_store[(int) mode])
       || GET_CODE (target) == REG
       || GET_CODE (target) == SUBREG
-      /* If the field isn't aligned enough to fetch as a unit,
-        fetch it as a bit field.  */
-#ifdef STRICT_ALIGNMENT
-      || align * BITS_PER_UNIT < GET_MODE_ALIGNMENT (mode)
-      || bitpos % GET_MODE_ALIGNMENT (mode) != 0
-#endif
-      )
+      /* If the field isn't aligned enough to store as an ordinary memref,
+        store it as a bit field.  */
+      || (STRICT_ALIGNMENT
+         && align * BITS_PER_UNIT < GET_MODE_ALIGNMENT (mode))
+      || (STRICT_ALIGNMENT && bitpos % GET_MODE_ALIGNMENT (mode) != 0))
     {
       rtx temp = expand_expr (exp, NULL_RTX, VOIDmode, 0);
       /* Store the value in the bitfield.  */
@@ -3970,18 +3968,23 @@ expand_expr (exp, target, tmode, modifier)
            MEM_VOLATILE_P (op0) = 1;
          }
 
+       /* In cases where an aligned union has an unaligned object
+          as a field, we might be extracting a BLKmode value from
+          an integer-mode (e.g., SImode) object.  Handle this case
+          by doing the extract into an object as wide as the field
+          (which we know to be the width of a basic mode), then
+          storing into memory, and changing the mode to BLKmode.  */
        if (mode1 == VOIDmode
            || (mode1 != BLKmode && ! direct_load[(int) mode1]
                && modifier != EXPAND_CONST_ADDRESS
                && modifier != EXPAND_SUM && modifier != EXPAND_INITIALIZER)
-           || GET_CODE (op0) == REG || GET_CODE (op0) == SUBREG)
+           || GET_CODE (op0) == REG || GET_CODE (op0) == SUBREG
+           /* If the field isn't aligned enough to fetch as a memref,
+              fetch it as a bit field.  */
+           || (STRICT_ALIGNMENT
+               && TYPE_ALIGN (TREE_TYPE (tem)) < GET_MODE_ALIGNMENT (mode))
+           || (STRICT_ALIGNMENT && bitpos % GET_MODE_ALIGNMENT (mode) != 0))
          {
-           /* In cases where an aligned union has an unaligned object
-              as a field, we might be extracting a BLKmode value from
-              an integer-mode (e.g., SImode) object.  Handle this case
-              by doing the extract into an object as wide as the field
-              (which we know to be the width of a basic mode), then
-              storing into memory, and changing the mode to BLKmode.  */
            enum machine_mode ext_mode = mode;
 
            if (ext_mode == BLKmode)