duskos

commit 4b7527215f84849241e07354fd80c5de090ecef6
parent 336a34a9ce67e938a64a545a5f75c7385886dfc3
Author: Virgil Dupras <hsoft@hardcoded.net>
Date:   Thu, 23 Jun 2022 14:04:58 -0400

cc: make funcmap fields into lib/struct unbounded fields

Diffstat:
M
fs/cc/gen.fs
 | 
2
+-
M
fs/cc/map.fs
 | 
19
++++++++-----------
M
fs/lib/struct.fs
 | 
20
++++++++++++++++++++

3 files changed, 29 insertions(+), 12 deletions(-)
diff --git a/fs/cc/gen.fs b/fs/cc/gen.fs
@@ -140,7 +140,7 @@ ASTIDCNT wordtbl gentbl ( node -- )
   ops$
   dup data1 entry
   dup data2 ( astfunc mapfunc )
-  here over fmap.address! \ set address
+  here over to fmap.address \ set address
   dup fmap.argsize swap fmap.sfsize over - ( argsz locsz ) vmprelude,
   genchildren
   _debug if current here current - spit nl> then ;
diff --git a/fs/cc/map.fs b/fs/cc/map.fs
@@ -19,15 +19,12 @@
 \ 4b link to AST_DECLARE node
 newxdict curmap
 
-: fmap.astnode @ ;
-: fmap.sfsize 4 + @ ;
-\ Return fmap Stack Frame size and then increase it by 4.
-: fmap.sfsize+ ( n fmap -- ) 4 + +! ;
-: fmap.argsize 8 + @ ;
-: fmap.argsize+ ( n fmap -- ) 8 + +! ;
-: fmap.address 12 + @ ;
-: fmap.address! 12 + ! ;
-: fmap.vmap 16 + ;
+\ Funcmap. Unbounded fields because the full struct generates more noise in the
+\ code.
+4  ufield  fmap.sfsize
+8  ufield  fmap.argsize
+12 ufield  fmap.address
+16 'ufield fmap.vmap
 
 struct Varmap
   field vmap.sfoff
@@ -53,7 +50,7 @@ struct Varmap
   curmap @ fmap.sfsize , dup , ( dnode )
   dup data2 ( dnode type ) typesize swap data3 ( nbelem )
   1 max * ( sfsize )
-  curmap @ fmap.sfsize+ ;
+  curmap @ to+ fmap.sfsize ;
 
 : findvarinmap ( name funcentry -- varentry )
   fmap.vmap xfind not if _err then ;
@@ -64,7 +61,7 @@ struct Varmap
   dup Function ( astfunc fmap ) over data2! ( astfunc ) begin ( curnode )
     AST_DECLARE nextnodeid dup if ( astdecl )
       dup parentnode nodeid AST_ARGSPECS = if \ inc argssize field
-        4 curmap @ fmap.argsize+ then
+        4 curmap @ to+ fmap.argsize then
       dup Variable 0 else 1 then
   until ( curnode ) drop  ;
 
diff --git a/fs/lib/struct.fs b/fs/lib/struct.fs
@@ -29,3 +29,23 @@
 
 : field doer laststruct to' execute , lastoffset , 4 to+ lastoffset does>
   dup @ @ swap 4 + @ + to? ?dup if execute else @ then ;
+
+\ A 'field returns the address of the field instead of the value. It doesn't
+\ follow "to" semantics and does not increase struct size.
+: 'field doer laststruct to' execute , lastoffset , does>
+  dup @ @ swap 4 + @ + ;
+
+\ Unbounded fields
+\ These works a bit like struct fields, but without an associated struct. In
+\ some cases, it makes more sense to have them instead of a full struct. Each
+\ invocation of them require the struct's address on the top of PS. They also
+\ support "to" semantics, but they are a bit awkward. Example:
+
+\ 4 ( offset ) ufield foo
+\ $1234 foo ( equivalent to $1238 @ )
+\ 42 $1234 to+ foo ( equivalent to 42 $1238 +! )
+
+: ufield ( off -- ) doer , does> ( a 'w )
+  @ + to? ?dup if execute else @ then ;
+
+: 'ufield ( off -- ) doer , does> ( a 'w ) @ + ;