Currently, Binutils still comes with an AVR_TINY linker description file
which puts .rodata into RAM so that LDS is applicable for reading such
objects.
However, as these devices come with a linearised address model, linker
descriptions which put .rodata into flash are much more reasonable.
This patch caters for such situations: As .rodata virtual addresses
will be offset by 0x4000, respective objects may no more be accessed by LDS.
Moreover, objects with a section attribute won't be accessed by LDS.
Ok for trunk?
Johann
PR target/78093
* config/avr/avr.c (avr_decl_maybe_lds_p): New static function.
(avr_encode_section_info) [TARGET_ABSDATA && AVR_TINY]: Use it.
Index: config/avr/avr.c
===================================================================
--- config/avr/avr.c (revision 242544)
+++ config/avr/avr.c (working copy)
@@ -10102,6 +10102,33 @@ avr_section_type_flags (tree decl, const
}
+/* A helper for the next function. NODE is a decl that is associated with
+ a symbol. Return TRUE if the respective object may be accessed by LDS.
+ There migth still be other reasons for why LDS is not appropriate.
+ This function is only useful for AVR_TINY. */
+
+static bool
+avr_decl_maybe_lds_p (tree node)
+{
+ if (!node
+ || TREE_CODE (node) != VAR_DECL
+ || DECL_SECTION_NAME (node) != NULL)
+ return false;
+
+ if (TREE_READONLY (node))
+ return true;
+
+ // C++ requires peeling arrays.
+
+ do
+ node = TREE_TYPE (node);
+ while (ARRAY_TYPE == TREE_CODE (node));
+
+ return (node != error_mark_node
+ && !TYPE_READONLY (node));
+}
+
+
/* Implement `TARGET_ENCODE_SECTION_INFO'. */
static void
@@ -10193,7 +10220,8 @@ avr_encode_section_info (tree decl, rtx
if (avr_decl_absdata_p (decl, DECL_ATTRIBUTES (decl))
|| (TARGET_ABSDATA
&& !progmem_p
- && !addr_attr)
+ && !addr_attr
+ && avr_decl_maybe_lds_p (decl))
|| (addr_attr
// If addr_attr is non-null, it has an argument. Peek into it.
&& TREE_INT_CST_LOW (TREE_VALUE (TREE_VALUE (addr_attr))) < 0xc0))
