* sparc-tdep.c (sparc32_return_value): Convert to use

RETURN_VALUE_ABI_PRESERVES_ADDRESS instead of
RETURN_VALUE_STRUCT_CONVENTION.
(sparc32_extract_struct_value_address): Remove.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 42ba8cc0a29b10db882b045528ef8e3c806b1752..94ad4e7e65f1aee34d252e7ba1452bd825c0f0f5 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,10 @@
+2006-01-22  Mark Kettenis  <kettenis@gnu.org>
+
+       * sparc-tdep.c (sparc32_return_value): Convert to use
+       RETURN_VALUE_ABI_PRESERVES_ADDRESS instead of
+       RETURN_VALUE_STRUCT_CONVENTION.
+       (sparc32_extract_struct_value_address): Remove.
+
 2006-01-21  Daniel Jacobowitz  <dan@codesourcery.com>
 
        * avr-tdep.c (avr_address_to_pointer, avr_pointer_to_address)

diff --git a/gdb/sparc-tdep.c b/gdb/sparc-tdep.c
index 7aa51a970fb6bc2d47eb5aeb6aec4d6ca709739b..ab9f1044c10caa183a6b64bf115742fcd9e74e2f 100644 (file)
--- a/gdb/sparc-tdep.c
+++ b/gdb/sparc-tdep.c
@@ -1,6 +1,6 @@
 /* Target-dependent code for SPARC.
 
-   Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -956,9 +956,28 @@ sparc32_return_value (struct gdbarch *gdbarch, struct type *type,
                      struct regcache *regcache, gdb_byte *readbuf,
                      const gdb_byte *writebuf)
 {
+  /* The psABI says that "...every stack frame reserves the word at
+     %fp+64.  If a function returns a structure, union, or
+     quad-precision value, this word should hold the address of the
+     object into which the return value should be copied."  This
+     guarantees that we can always find the return value, not just
+     before the function returns.  */
+
   if (sparc_structure_or_union_p (type)
       || (sparc_floating_p (type) && TYPE_LENGTH (type) == 16))
-    return RETURN_VALUE_STRUCT_CONVENTION;
+    {
+      if (readbuf)
+       {
+         ULONGEST sp;
+         CORE_ADDR addr;
+
+         regcache_cooked_read_unsigned (regcache, SPARC_SP_REGNUM, &sp);
+         addr = read_memory_unsigned_integer (sp + 64, 4);
+         read_memory (addr, readbuf, TYPE_LENGTH (type));
+       }
+
+      return RETURN_VALUE_ABI_PRESERVES_ADDRESS;
+    }
 
   if (readbuf)
     sparc32_extract_return_value (type, regcache, readbuf);
@@ -968,32 +987,6 @@ sparc32_return_value (struct gdbarch *gdbarch, struct type *type,
   return RETURN_VALUE_REGISTER_CONVENTION;
 }
 
-#if 0
-/* NOTE: cagney/2004-01-17: For the moment disable this method.  The
-   architecture and CORE-gdb will need new code (and a replacement for
-   DEPRECATED_EXTRACT_STRUCT_VALUE_ADDRESS) before this can be made to
-   work robustly.  Here is a possible function signature: */
-/* NOTE: cagney/2004-01-17: So far only the 32-bit SPARC ABI has been
-   identifed as having a way to robustly recover the address of a
-   struct-convention return-value (after the function has returned).
-   For all other ABIs so far examined, the calling convention makes no
-   guarenteed that the register containing the return-value will be
-   preserved and hence that the return-value's address can be
-   recovered.  */
-/* Extract from REGCACHE, which contains the (raw) register state, the
-   address in which a function should return its structure value, as a
-   CORE_ADDR.  */
-
-static CORE_ADDR
-sparc32_extract_struct_value_address (struct regcache *regcache)
-{
-  ULONGEST sp;
-
-  regcache_cooked_read_unsigned (regcache, SPARC_SP_REGNUM, &sp);
-  return read_memory_unsigned_integer (sp + 64, 4);
-}
-#endif
-
 static int
 sparc32_stabs_argument_has_addr (struct gdbarch *gdbarch, struct type *type)
 {