commit 4e65a17e62c7c2f3c0409d9769cca2e916a88379
Author: Andreas Arnez <arnez@linux.vnet.ibm.com>
Date: Mon Apr 27 11:38:47 2015 +0200
S390: Re-arrange implementation of s390_return_value
Move related logic in the implementation of s390_return_value closer
together. This makes it easier to read and extend.
gdb/ChangeLog:
* s390-linux-tdep.c (s390_return_value_convention): Remove
function. Inline its logic...
(s390_return_value): ...here. Instead, move the handling of the
"register" return value convention...
(s390_register_return_value): ...here. New function.
### a/gdb/ChangeLog
### b/gdb/ChangeLog
## -1,5 +1,13 @@
2015-04-27 Andreas Arnez <arnez@linux.vnet.ibm.com>
+ * s390-linux-tdep.c (s390_return_value_convention): Remove
+ function. Inline its logic...
+ (s390_return_value): ...here. Instead, move the handling of the
+ "register" return value convention...
+ (s390_register_return_value): ...here. New function.
+
+2015-04-27 Andreas Arnez <arnez@linux.vnet.ibm.com>
+
* s390-linux-tdep.c
(is_float_singleton): Remove function. Move the "singleton" part
of the logic...
Index: gdb-7.6.1/gdb/s390-tdep.c
===================================================================
--- gdb-7.6.1.orig/gdb/s390-tdep.c 2016-02-21 22:31:47.311935241 +0100
+++ gdb-7.6.1/gdb/s390-tdep.c 2016-02-21 22:31:59.326029901 +0100
@@ -2865,110 +2865,98 @@
}
-/* Function return value access. */
+/* Helper for s390_return_value: Set or retrieve a function return
+ value if it resides in a register. */
-static enum return_value_convention
-s390_return_value_convention (struct gdbarch *gdbarch, struct type *type)
+static void
+s390_register_return_value (struct gdbarch *gdbarch, struct type *type,
+ struct regcache *regcache,
+ gdb_byte *out, const gdb_byte *in)
{
- if (TYPE_LENGTH (type) > 8)
- return RETURN_VALUE_STRUCT_CONVENTION;
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ int word_size = gdbarch_ptr_bit (gdbarch) / 8;
+ int length = TYPE_LENGTH (type);
+ int code = TYPE_CODE (type);
- switch (TYPE_CODE (type))
+ if (code == TYPE_CODE_FLT || code == TYPE_CODE_DECFLOAT)
{
- case TYPE_CODE_STRUCT:
- case TYPE_CODE_UNION:
- case TYPE_CODE_ARRAY:
- case TYPE_CODE_COMPLEX:
- return RETURN_VALUE_STRUCT_CONVENTION;
-
- default:
- return RETURN_VALUE_REGISTER_CONVENTION;
+ /* Float-like value: left-aligned in f0. */
+ if (in != NULL)
+ regcache_cooked_write_part (regcache, S390_F0_REGNUM,
+ 0, length, in);
+ else
+ regcache_cooked_read_part (regcache, S390_F0_REGNUM,
+ 0, length, out);
+ }
+ else if (length <= word_size)
+ {
+ /* Integer: zero- or sign-extended in r2. */
+ if (out != NULL)
+ regcache_cooked_read_part (regcache, S390_R2_REGNUM,
+ word_size - length, length, out);
+ else if (TYPE_UNSIGNED (type))
+ regcache_cooked_write_unsigned
+ (regcache, S390_R2_REGNUM,
+ extract_unsigned_integer (in, length, byte_order));
+ else
+ regcache_cooked_write_signed
+ (regcache, S390_R2_REGNUM,
+ extract_signed_integer (in, length, byte_order));
}
+ else if (length == 2 * word_size)
+ {
+ /* Double word: in r2 and r3. */
+ if (in != NULL)
+ {
+ regcache_cooked_write (regcache, S390_R2_REGNUM, in);
+ regcache_cooked_write (regcache, S390_R3_REGNUM,
+ in + word_size);
+ }
+ else
+ {
+ regcache_cooked_read (regcache, S390_R2_REGNUM, out);
+ regcache_cooked_read (regcache, S390_R3_REGNUM,
+ out + word_size);
+ }
+ }
+ else
+ internal_error (__FILE__, __LINE__, _("invalid return type"));
}
+
+/* Implement the 'return_value' gdbarch method. */
+
static enum return_value_convention
s390_return_value (struct gdbarch *gdbarch, struct value *function,
struct type *type, struct regcache *regcache,
gdb_byte *out, const gdb_byte *in)
{
- enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
- int word_size = gdbarch_ptr_bit (gdbarch) / 8;
enum return_value_convention rvc;
- int length;
type = check_typedef (type);
- rvc = s390_return_value_convention (gdbarch, type);
- length = TYPE_LENGTH (type);
- if (in)
+ switch (TYPE_CODE (type))
{
- switch (rvc)
- {
- case RETURN_VALUE_REGISTER_CONVENTION:
- if (TYPE_CODE (type) == TYPE_CODE_FLT
- || TYPE_CODE (type) == TYPE_CODE_DECFLOAT)
- {
- /* When we store a single-precision value in an FP register,
- it occupies the leftmost bits. */
- regcache_cooked_write_part (regcache, S390_F0_REGNUM,
- 0, length, in);
- }
- else if (length <= word_size)
- {
- /* Integer arguments are always extended to word size. */
- if (TYPE_UNSIGNED (type))
- regcache_cooked_write_unsigned (regcache, S390_R2_REGNUM,
- extract_unsigned_integer (in, length, byte_order));
- else
- regcache_cooked_write_signed (regcache, S390_R2_REGNUM,
- extract_signed_integer (in, length, byte_order));
- }
- else if (length == 2*word_size)
- {
- regcache_cooked_write (regcache, S390_R2_REGNUM, in);
- regcache_cooked_write (regcache, S390_R3_REGNUM, in + word_size);
- }
- else
- internal_error (__FILE__, __LINE__, _("invalid return type"));
- break;
-
- case RETURN_VALUE_STRUCT_CONVENTION:
- error (_("Cannot set function return value."));
- break;
- }
+ case TYPE_CODE_STRUCT:
+ case TYPE_CODE_UNION:
+ case TYPE_CODE_ARRAY:
+ case TYPE_CODE_COMPLEX:
+ rvc = RETURN_VALUE_STRUCT_CONVENTION;
+ break;
+ default:
+ rvc = TYPE_LENGTH (type) <= 8
+ ? RETURN_VALUE_REGISTER_CONVENTION
+ : RETURN_VALUE_STRUCT_CONVENTION;
}
- else if (out)
+
+ if (in != NULL || out != NULL)
{
- switch (rvc)
- {
- case RETURN_VALUE_REGISTER_CONVENTION:
- if (TYPE_CODE (type) == TYPE_CODE_FLT
- || TYPE_CODE (type) == TYPE_CODE_DECFLOAT)
- {
- /* When we store a single-precision value in an FP register,
- it occupies the leftmost bits. */
- regcache_cooked_read_part (regcache, S390_F0_REGNUM,
- 0, length, out);
- }
- else if (length <= word_size)
- {
- /* Integer arguments occupy the rightmost bits. */
- regcache_cooked_read_part (regcache, S390_R2_REGNUM,
- word_size - length, length, out);
- }
- else if (length == 2*word_size)
- {
- regcache_cooked_read (regcache, S390_R2_REGNUM, out);
- regcache_cooked_read (regcache, S390_R3_REGNUM, out + word_size);
- }
- else
- internal_error (__FILE__, __LINE__, _("invalid return type"));
- break;
-
- case RETURN_VALUE_STRUCT_CONVENTION:
- error (_("Function return value unknown."));
- break;
- }
+ if (rvc == RETURN_VALUE_REGISTER_CONVENTION)
+ s390_register_return_value (gdbarch, type, regcache, out, in);
+ else if (in != NULL)
+ error (_("Cannot set function return value."));
+ else
+ error (_("Function return value unknown."));
}
return rvc;