forth-riscv

commit 46778b08a87e3a4fdf6b51d9cebd88ba3774ec06
parent 80594583cf6f4ef673ad841d171c21ceced988d3
Author: Christian Ermann <christianermann@gmail.com>
Date:   Wed, 13 Nov 2024 12:31:49 -0800

Add ';does'

Diffstat:
M
forth.s
 | 
38
++++++++++++++++++++++++++++++++++++++

1 file changed, 38 insertions(+), 0 deletions(-)
diff --git a/forth.s b/forth.s
@@ -152,6 +152,13 @@ docon:
     push w
     next
 
+dodoes:
+    push_ret ip     # save old ip
+    addi w, w, cell # make w point to parameter field
+    push w          # push w onto param. stack
+    mv ip, ra       # set new ip
+    next
+
 defcode "exit", exit, 0xCDED1A85
     pop_ret ip
     next
@@ -957,6 +964,37 @@ defword "constant", constant, 0x0691EA25
     .int comma              # initialize to value on stack
     .int exit
 
+defcode "jal-dodoes", jal_dodoes, 0x4F82E787
+    pop w
+    la x, dodoes
+    sub x, x, w
+    li y, 0x000FF000      # imm[19:12]
+    and w, x, y
+    li y, 0x00100000      # imm[20]
+    and y, x, y
+    slli y, y, 11
+    add w, w, y
+    li y, 0x00000800      # imm[11]
+    and y, x, y
+    slli y, y, 9
+    add w, w, y
+    andi y, x, 0x000007FE # imm[10:1]
+    slli y, y, 20
+    add w, w, y
+    addi w, w, 0x000000EF # jal ra, imm
+    push w
+    next
+
+defword ";does", does, 0xF5BCD777, flags=flag_immediate
+    .int lit, does_internal, comma
+    .int here, jal_dodoes, comma
+    .int exit
+
+defword "(;does)", does_internal, 0xED4B7678
+    .int from_ret
+    .int latest, fetch, lit, code_offset, plus, store
+    .int exit
+
 defcode "read-char", read_char, 0xF07E2044
     jal _read_char_impl
     push w