Compute enumeration storage types more accurately

Previously we just were sloppy and didn't bother to accurately compute
signed/unsigned for enumeration types.  But since we expect bindings
to decode a field value or function return value from an integer to
an enumeration they have know whether an integer value is
0xffffffff or -1, so we need to do the full computation.

https://bugzilla.gnome.org/show_bug.cgi?id=629704
This commit is contained in:
Owen W. Taylor 2010-09-14 14:17:35 -04:00
parent aa154a1776
commit 7fa7162361

View File

@ -23,9 +23,9 @@
#include <string.h>
/* The C standard specifies that an enumeration can be any char or any signed
* or unsigned integer type capable of resresenting all the values of the
* or unsigned integer type capable of representing all the values of the
* enumeration. We use test enumerations to figure out what choices the
* compiler makes.
* compiler makes. (Ignoring > 32 bit enumerations)
*/
typedef enum {
@ -52,24 +52,26 @@ typedef enum {
ENUM_6 = ((guint)G_MAXINT) + 1 /* compiler could use uint32 */
} Enum6;
/* GIrNodeValue has guint32 values, so if it matters to the ABI whether
* constant values are signed, we are in trouble. And we don't handle
* enums with > 32 bit values. */
#if 0
typedef enum {
ENUM_7 = -1 /* compiler could use int8, int16, int32 */
} Enum7;
/* etc... */
#endif
typedef enum {
ENUM_8 = -129 /* compiler could use int16, int32 */
} Enum8;
typedef enum {
ENUM_9 = G_MINSHORT - 1 /* compiler could use int32 */
} Enum9;
static void
compute_enum_storage_type (GIrNodeEnum *enum_node)
{
GList *l;
gint32 max_value = 0;
gint64 max_value = 0;
gint64 min_value = 0;
int width;
gboolean signed_type;
if (enum_node->storage_type != GI_TYPE_TAG_VOID) /* already done */
return;
@ -79,29 +81,63 @@ compute_enum_storage_type (GIrNodeEnum *enum_node)
GIrNodeValue *value = l->data;
if (value->value > max_value)
max_value = value->value;
if (value->value < min_value)
min_value = value->value;
}
if (max_value < 128)
width = sizeof (Enum1);
else if (max_value < 256)
width = sizeof (Enum2);
else if (max_value < G_MAXSHORT)
width = sizeof (Enum3);
else if (max_value < G_MAXUSHORT)
width = sizeof (Enum4);
else if (max_value < G_MAXINT)
width = sizeof (Enum5);
if (min_value < 0)
{
signed_type = TRUE;
if (min_value > -128 && max_value <= 127)
width = sizeof(Enum7);
else if (min_value >= G_MINSHORT && max_value <= G_MAXSHORT)
width = sizeof(Enum8);
else
width = sizeof(Enum9);
}
else
width = sizeof (Enum6);
{
if (max_value <= 127)
{
width = sizeof (Enum1);
signed_type = (gint64)(Enum1)(-1) < 0;
}
else if (max_value <= 255)
{
width = sizeof (Enum2);
signed_type = (gint64)(Enum2)(-1) < 0;
}
else if (max_value <= G_MAXSHORT)
{
width = sizeof (Enum3);
signed_type = (gint64)(Enum3)(-1) < 0;
}
else if (max_value <= G_MAXUSHORT)
{
width = sizeof (Enum4);
signed_type = (gint64)(Enum4)(-1) < 0;
}
else if (max_value <= G_MAXINT)
{
width = sizeof (Enum5);
signed_type = (gint64)(Enum5)(-1) < 0;
}
else
{
width = sizeof (Enum6);
signed_type = (gint64)(Enum6)(-1) < 0;
}
}
if (width == 1)
enum_node->storage_type = GI_TYPE_TAG_UINT8;
enum_node->storage_type = signed_type ? GI_TYPE_TAG_INT8 : GI_TYPE_TAG_UINT8;
else if (width == 2)
enum_node->storage_type = GI_TYPE_TAG_UINT16;
enum_node->storage_type = signed_type ? GI_TYPE_TAG_INT16 : GI_TYPE_TAG_UINT16;
else if (width == 4)
enum_node->storage_type = GI_TYPE_TAG_UINT32;
enum_node->storage_type = signed_type ? GI_TYPE_TAG_INT32 : GI_TYPE_TAG_UINT32;
else if (width == 8)
enum_node->storage_type = GI_TYPE_TAG_UINT64;
enum_node->storage_type = signed_type ? GI_TYPE_TAG_INT64 : GI_TYPE_TAG_UINT64;
else
g_error ("Unexpected enum width %d", width);
}