Squashed 'third_party/elfutils/' content from commit 555e15e
Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/backends/m68k_retval.c b/backends/m68k_retval.c
new file mode 100644
index 0000000..a653ba3
--- /dev/null
+++ b/backends/m68k_retval.c
@@ -0,0 +1,151 @@
+/* Function return value location for Linux/m68k ABI.
+ This file is part of elfutils.
+
+ This file is free software; you can redistribute it and/or modify
+ it under the terms of either
+
+ * the GNU Lesser General Public License as published by the Free
+ Software Foundation; either version 3 of the License, or (at
+ your option) any later version
+
+ or
+
+ * the GNU General Public License as published by the Free
+ Software Foundation; either version 2 of the License, or (at
+ your option) any later version
+
+ or both in parallel, as here.
+
+ elfutils is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received copies of the GNU General Public License and
+ the GNU Lesser General Public License along with this program. If
+ not, see <http://www.gnu.org/licenses/>. */
+
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <assert.h>
+#include <dwarf.h>
+
+#define BACKEND m68k_
+#include "libebl_CPU.h"
+
+
+/* %d0, or pair %d0, %d1. */
+static const Dwarf_Op loc_intreg[] =
+ {
+ { .atom = DW_OP_reg0 }, { .atom = DW_OP_piece, .number = 4 },
+ { .atom = DW_OP_reg1 }, { .atom = DW_OP_piece, .number = 4 },
+ };
+#define nloc_intreg 1
+#define nloc_intregpair 4
+
+/* %a0. */
+static const Dwarf_Op loc_ptrreg[] =
+ {
+ { .atom = DW_OP_reg8 }
+ };
+#define nloc_ptrreg 1
+
+/* %fp0. */
+static const Dwarf_Op loc_fpreg[] =
+ {
+ { .atom = DW_OP_reg16 }
+ };
+#define nloc_fpreg 1
+
+/* The return value is a structure and is actually stored in stack space
+ passed in a hidden argument by the caller. But, the compiler
+ helpfully returns the address of that space in %a0. */
+static const Dwarf_Op loc_aggregate[] =
+ {
+ { .atom = DW_OP_reg8 }
+ };
+#define nloc_aggregate 1
+
+int
+m68k_return_value_location (Dwarf_Die *functypedie, const Dwarf_Op **locp)
+{
+ /* Start with the function's type, and get the DW_AT_type attribute,
+ which is the type of the return value. */
+ Dwarf_Die die_mem, *typedie = &die_mem;
+ int tag = dwarf_peeled_die_type (functypedie, typedie);
+ if (tag <= 0)
+ return tag;
+
+ switch (tag)
+ {
+ case -1:
+ return -1;
+
+ case DW_TAG_subrange_type:
+ if (! dwarf_hasattr_integrate (typedie, DW_AT_byte_size))
+ {
+ Dwarf_Attribute attr_mem, *attr;
+ attr = dwarf_attr_integrate (typedie, DW_AT_type, &attr_mem);
+ typedie = dwarf_formref_die (attr, &die_mem);
+ tag = DWARF_TAG_OR_RETURN (typedie);
+ }
+ FALLTHROUGH;
+
+ case DW_TAG_base_type:
+ case DW_TAG_enumeration_type:
+ case DW_TAG_pointer_type:
+ case DW_TAG_ptr_to_member_type:
+ {
+ Dwarf_Word size;
+ Dwarf_Attribute attr_mem;
+ if (dwarf_formudata (dwarf_attr_integrate (typedie, DW_AT_byte_size,
+ &attr_mem), &size) != 0)
+ {
+ if (tag == DW_TAG_pointer_type || tag == DW_TAG_ptr_to_member_type)
+ size = 4;
+ else
+ return -1;
+ }
+ if (tag == DW_TAG_base_type)
+ {
+ Dwarf_Word encoding;
+ if (dwarf_formudata (dwarf_attr_integrate (typedie, DW_AT_encoding,
+ &attr_mem),
+ &encoding) != 0)
+ return -1;
+ if (encoding == DW_ATE_float)
+ {
+ if (size > 12)
+ return -2;
+ *locp = loc_fpreg;
+ return nloc_fpreg;
+ }
+ }
+ if (tag == DW_TAG_pointer_type || tag == DW_TAG_ptr_to_member_type)
+ {
+ *locp = loc_ptrreg;
+ return nloc_ptrreg;
+ }
+ *locp = loc_intreg;
+ if (size <= 4)
+ return nloc_intreg;
+ if (size <= 8)
+ return nloc_intregpair;
+ }
+ FALLTHROUGH;
+ case DW_TAG_structure_type:
+ case DW_TAG_class_type:
+ case DW_TAG_union_type:
+ case DW_TAG_array_type:
+ *locp = loc_aggregate;
+ return nloc_aggregate;
+ }
+
+ /* XXX We don't have a good way to return specific errors from ebl calls.
+ This value means we do not understand the type, but it is well-formed
+ DWARF and might be valid. */
+ return -2;
+}