time: rearrange+pack vtm and time_object structs

struct time_object shrinks from 88 to 46 bytes on my 64-bit system.

* configure.in: use -Wno-packed-bitfield-compat for GCC 4.4+
  use __attribute__((packed)) if available
* timev.h: shrink and pack struct vtm
* time.c: pack struct time_object and adjust/introduce helpers
  [ruby-core:60794]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45155 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 9 insertions, 9 deletions

diff --git a/timev.h b/timev.h
index 983ef66b80..eda7023eb3 100644
--- a/timev.h
+++ b/timev.h
@@ -3,18 +3,18 @@
 
 struct vtm {
     VALUE year; /* 2000 for example.  Integer. */
-    int mon; /* 1..12 */
-    int mday; /* 1..31 */
-    int hour; /* 0..23 */
-    int min; /* 0..59 */
-    int sec; /* 0..60 */
     VALUE subsecx; /* 0 <= subsecx < TIME_SCALE.  possibly Rational. */
     VALUE utc_offset; /* -3600 as -01:00 for example.  possibly Rational. */
-    int wday; /* 0:Sunday, 1:Monday, ..., 6:Saturday */
-    int yday; /* 1..366 */
-    int isdst; /* 0:StandardTime 1:DayLightSavingTime */
     const char *zone; /* "JST", "EST", "EDT", etc. */
-};
+    uint16_t yday:9; /* 1..366 */
+    uint8_t mon:4; /* 1..12 */
+    uint8_t mday:5; /* 1..31 */
+    uint8_t hour:5; /* 0..23 */
+    uint8_t min:6; /* 0..59 */
+    uint8_t sec:6; /* 0..60 */
+    uint8_t wday:3; /* 0:Sunday, 1:Monday, ..., 6:Saturday 7:init */
+    uint8_t isdst:2; /* 0:StandardTime 1:DayLightSavingTime 3:init */
+} PACKED_STRUCT;
 
 #define TIME_SCALE 1000000000