Start of adding code word support.

common/code.fs

@@ -0,0 +1,58 @@
+\ Copyright 2022 Bradley D. Nelson
+\
+\ Licensed under the Apache License, Version 2.0 (the "License");
+\ you may not use this file except in compliance with the License.
+\ You may obtain a copy of the License at
+\
+\     http://www.apache.org/licenses/LICENSE-2.0
+\
+\ Unless required by applicable law or agreed to in writing, software
+\ distributed under the License is distributed on an "AS IS" BASIS,
+\ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+\ See the License for the specific language governing permissions and
+\ limitations under the License.
+
+( Lazy loaded code words )
+: asm r|
+
+also forth definitions
+vocabulary asm   asm definitions
+also internals
+
+variable code-start
+variable code-at
+
+DEFINED? posix [IF]
+also posix
+: reserve ( n -- )
+  0 swap PROT_READ PROT_WRITE PROT_EXEC or or MAP_ANONYMOUS -1 0 mmap code-start ! ;
+previous
+4096 reserve
+[THEN]
+
+DEFINED? esp [IF]
+also esp
+: reserve ( n -- ) MALLOC_CAP_EXEC heap_caps_malloc code-start ! ;
+previous
+1024 reserve
+[THEN]
+
+code-start code-at !
+
+: chere ( -- a ) code-at @ ;
+: callot ( n -- ) code-at +! ;
+: code, ( n -- ) chere ! cell callot ;
+: code1, ( n -- ) chere c! 1 callot ;
+: code2, ( n -- ) chere w! 2 callot ;
+: code4, ( n -- ) chere l! 4 callot ;
+: end-code   previous ;
+
+also forth definitions
+
+: code ( "name" ) create ['] callcode @ latestxt !
+                  code-at @ latestxt cell+ ! also asm ;
+
+previous previous previous
+asm
+
+| evaluate ;