forth-riscv

commit 5609af2e7bbe0ad0344c771d2c32009748349a4c
parent 5ed02979dda27d3818f3e4e1ed72e8dd63fc3e6a
Author: Christian Ermann <christian.ermann@joescan.com>
Date:   Tue,  1 Jul 2025 20:28:01 -0700

Factor '(interpret-execute)'

Diffstat:
M
src/forth.s
 | 
49
++++++++++++++++++++++++++++++-------------------

1 file changed, 30 insertions(+), 19 deletions(-)
diff --git a/src/forth.s b/src/forth.s
@@ -847,37 +847,48 @@ _interpret_parse_area_empty:
     # ( addr len=0 -- )
     addi psp, psp, cell
     pop w
-    jal interpret_execute
-    exit
-
-defword "(interpret-execute)", interpret_execute, 0x2477F685
-    # check state
     la x, _state
     lw x, 0(x)
     li y, state_executing
-    bne x, y, _inner_interpret_done
-    # append 'exit'
-    jal exit_comma
-    # save current execution heap address
+    bne x, y, _interpret_done
+    jal interpret_execute
+_interpret_done:
+    exit
+
+defcode "nest-execution", nest_execution, 0xCCD56530
+    # ( -- exec-heap r: exec-heap )
     push w
-    la w, _exec_heap
-    lw x, 0(w)
-    push_ret x
-    # set new execution heap address past compiled code
+    # save exec heap address
+    la x, _exec_heap
+    lw w, 0(x)
+    push_ret w
+    # update exec heap to point past compiled code
     la y, _code_pointer
     lw y, 0(y)
-    sw y, 0(w)
-    pop w
-    # execute
-    jalr x
-    # reset code pointer and execution heap
+    sw y, 0(x)
+    next
+
+defcode "unnest-execution", unnest_execution, 0x9AC2B97B
+    # ( r: exec-heap -- )
+    # restore code compilation pointer
     pop_ret x
     la y, _code_pointer
     sw x, 0(y)
+    # restore exec heap address
     la y, _exec_heap
     sw x, 0(y)
+    next
+
+defword "(interpret-execute)", interpret_execute, 0x2477F685
+    # ( -- )
+    # append 'exit'
+    jal exit_comma
+    # run!
+    jal nest_execution
+    jal execute
+    jal unnest_execution
+    # append 'docol'
     jal docol_comma
-_inner_interpret_done:
     exit
 
 defcode "branch", branch, 0xB6873945