Hi Ludovic,
Great work on the struct optimizations!
Some comments:
-#define SCM_VTABLE_FLAG_RESERVED_0 (1L << 5)
-#define SCM_VTABLE_FLAG_RESERVED_1 (1L << 6)
+#define SCM_VTABLE_FLAG_SIMPLE (1L << 5) /* instances of this vtable have
only "pr" fields */
+#define SCM_VTABLE_FLAG_SIMPLE_RW (1L << 6) /* instances of this vtable
have only "pw" fields */
The comments do not appear to be correct, given a later check:
+ if (SCM_LIKELY (SCM_VTABLE_FLAG_IS_SET (vtable, SCM_VTABLE_FLAG_SIMPLE)
+ && SCM_VTABLE_FLAG_IS_SET (vtable, SCM_VTABLE_FLAG_SIMPLE_RW)
+ && p < SCM_STRUCT_DATA_REF (vtable, scm_vtable_index_size)))
+ /* The fast path: HANDLE is a struct with only "p" fields. */
+ data[p] = SCM_UNPACK (val);
It seems that currently SIMPLE is for all pr *or* all pw slots. But we
should be more orthogonal than that; let's have SIMPLE be for having all
slots be readable p slots. (Note that this still allows a mix of
readable and writable slots.)
Then perhaps we can change SIMPLE_RW to be MUTABLE or something, to
indicate that all slots of this object are mutable.
What do you think?
Andy
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