vm: function table for faster calls.

The vm now supports gcall and gapply opcodes which index
numerically (using an immediate integer field in the
instruction word) into a table of pre-resolved global function
bindings.

* share/txr/stdlib/asm.tl (op-gcall, op-gapply): New opcodes.
(disassemble-c-d): Take the function vector as an argument and
dump it too.
(usr:disassemble): Extract function vector from VM description
and pass it to disassemble-c-d.

* share/txr/stdlib/compiler.tl (usr:compile-toplevel): Pass
empty function symbol vector to vm-make-desc; it's now a
required argument.

* vm.c (struct vm_desc): New members funvec and ftab.
(struct vm_ftent): New struct type.
(vm_make_desc): New argument, funvec. Store funvec in the
descriptor. Allocate a table of vm_ftent structures equal in
number of elements to the function table, and populate it with
resolved bindings.
(vm_desc_funvec, vm_desc_destroy): New static functions.
(vm_desc_mark): Mark the captured bindings in vd->ftab.
(vm_gcall, vm_gapply): New static functions.
(vm_execute): Handle GCALL and GAPPLY opcodes.
(vm_desc_ops): Wire vm_desc_destroy in place of
cobj_destroy_free_op.
(vm_init): Add argument to vm-make-desc intrinsic. Register
vm-desc-funvec intrinsic.

* vm.h (vm_make_desc): Declaration updated.

* vmop.h: Regenerated

1 files changed, 2 insertions, 1 deletions

diff --git a/vm.h b/vm.h
index 42bd2b36..1a8a1c8e 100644
--- a/vm.h
+++ b/vm.h
@@ -25,7 +25,8 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-val vm_make_desc(val nlevels, val nregs, val bytecode, val datavec);
+val vm_make_desc(val nlevels, val nregs, val bytecode,
+                 val datavec, val funvec);
 val vm_execute_toplevel(val desc);
 val vm_execute_closure(val fun, struct args *);
 void vm_init(void);