vm/asm: reconfiguration of display dimensions.

Increasing the maximum frame width from 256 to 1024 words;
and reducing the max display depth from 256 to 64 frames.
Small operands use a 4:6 split: the first 64 words
of the first 16 levels can be accessed with a 10
bit operand.

* share/txr/stdlib/asm.tl (parse-operand): Adjust to
wider syntax for registers due to more digits.
The v registers are 5 hex digits now: 2 digit level,
and a 3 digit offset.
(with-lev-idx): New macro.
(operand-to-sym): Use with-lev-idx and rename variables
to lv and ix.
(small-op-p, enc-op-p, small-op-to-sym): Rewrite for 4:6 small
operand.

* share/txr/stdlib/vm-param.tl (%lev-size%, %lev-bits%,
%max-lev%): Adjust values.
(%sm-lev-size%, %max-sm-lev-idx%, sm-lev-bits%): New symbol
macros.

* vm.c (VM_LEV_BITS, VM_LEV_MASK, VM_SM_LEV_BITS,
VM_SM_LEV_MASK): Values adjusted.

1 files changed, 4 insertions, 4 deletions

diff --git a/vm.c b/vm.c
index 25a7b713..362f1adb 100644
--- a/vm.c
+++ b/vm.c
@@ -295,10 +295,10 @@ static void vm_reset(struct vm *vm, struct vm_desc *vd,
 #define vm_insn_bigop(insn) (((insn) & 0x3FFFFFFU))
 #define vm_arg_operand_lo(arg) ((arg) & 0xFFFFU)
 #define vm_arg_operand_hi(arg) ((arg) >> 16)
-#define VM_LEV_BITS 8
-#define VM_LEV_MASK 0xFF
-#define VM_SM_LEV_BITS 8
-#define VM_SM_LEV_MASK 0xFF
+#define VM_LEV_BITS 10
+#define VM_LEV_MASK 0x3FF
+#define VM_SM_LEV_BITS 6
+#define VM_SM_LEV_MASK 0x3F
 #define vm_lev(arg) ((arg) >> VM_LEV_BITS)
 #define vm_idx(arg) ((arg) & VM_LEV_MASK)
 #define vm_sm_lev(arg) ((arg) >> VM_SM_LEV_BITS)