[PATCH] Fix printing functions with complex return on PPC64

[Tiago Stürmer Daitx]

This patch fix the current PPC64 return value code to properly handle complex 
types by passing the target type of the COMPLEX value. It also makes use of a
variable to hold TYPE_TARGET_TYPE (valtype) for better readability and reuse.

Previously two testcases from gdb.base/callfuncs.exp and another two from
gdb.base/varargs.exp would fail with GDB Interal Error due to improperly
calling convert_typed_floating with a COMPLEX type instead of using the
target type.

Excerpt from a diff between PPC64 run log before and after the fix:

  -FAIL: gdb.base/callfuncs.exp: call inferior func with struct - returns float _Complex (GDB internal error)
  -FAIL: gdb.base/callfuncs.exp: call inferior func with struct - returns double _Complex (GDB internal error)

  -FAIL: gdb.base/varargs.exp: print find_max_float_real(4, fc1, fc2, fc3, fc4) (GDB internal error)
  -FAIL: gdb.base/varargs.exp: print find_max_double_real(4, dc1, dc2, dc3, dc4) (GDB internal error)
  +FAIL: gdb.base/varargs.exp: print find_max_float_real(4, fc1, fc2, fc3, fc4)

The existing FAIL is due to the complex arguments and will be fixed by another 
patch series.

No regression was detected on PPC (32 bits) testcases.

Regards,
Tiago Daitx


gdb/Changelog

2012-11-01  Tiago Stürmer Daitx  <tdaitx@linux.vnet.ibm.com>

        * ppc-sysv-tdep.c (ppc64_sysv_abi_return_value): Set correct
        type on float conversion for complex type.
---
diff --git a/gdb/ppc-sysv-tdep.c b/gdb/ppc-sysv-tdep.c
index 48b4765..0ffeab9 100644
--- a/gdb/ppc-sysv-tdep.c
+++ b/gdb/ppc-sysv-tdep.c
@@ -1920,11 +1920,13 @@ ppc64_sysv_abi_return_value (struct gdbarch *gdbarch, struct value *function,
 	      gdb_byte regval[MAX_REGISTER_SIZE];
 	      struct type *regtype =
 		register_type (gdbarch, tdep->ppc_fp0_regnum);
+	      struct type *target_type;
+	      target_type = check_typedef (TYPE_TARGET_TYPE (valtype));
 	      if (writebuf != NULL)
 		{
 		  convert_typed_floating ((const bfd_byte *) writebuf +
-					  i * (TYPE_LENGTH (valtype) / 2),
-					  valtype, regval, regtype);
+					  i * TYPE_LENGTH (target_type), 
+					  target_type, regval, regtype);
 		  regcache_cooked_write (regcache,
                                          tdep->ppc_fp0_regnum + 1 + i,
 					 regval);
@@ -1936,8 +1938,8 @@ ppc64_sysv_abi_return_value (struct gdbarch *gdbarch, struct value *function,
                                         regval);
 		  convert_typed_floating (regval, regtype,
 					  (bfd_byte *) readbuf +
-					  i * (TYPE_LENGTH (valtype) / 2),
-					  valtype);
+					  i * TYPE_LENGTH (target_type),
+					  target_type);
 		}
 	    }
 	}