duskos

commit e1b098643da1705e2bb0c4da64911432ded32325
parent 0bcc434a07e05ccb176a83d857d71de1fe648a30
Author: Virgil Dupras <hsoft@hardcoded.net>
Date:   Sun, 19 Mar 2023 18:01:14 -0400

halcc: add static tmp space to solve argument swapping problems

Diffstat:
M
fs/comp/c/egen.fs
 | 
15
+++++----------
M
fs/comp/c/expr.fs
 | 
6
++++++
M
fs/comp/c/gen.fs
 | 
4
++--

3 files changed, 13 insertions(+), 12 deletions(-)
diff --git a/fs/comp/c/egen.fs b/fs/comp/c/egen.fs
@@ -77,23 +77,18 @@ swappable _+, +,   swappable _*, *,
 swappable _&, and, swappable _^, xor,  swappable _|, or,
 
 : fixed doer ' , does> @ ( left right w ) >r
-  over Result :>W Result :hal# r> execute ;
+  Result :?>tmp over Result :>W r> execute ;
 fixed _-, -,       fixed _/, /,        fixed _%, %,
 fixed _<<, <<,     fixed _>>, >>,
 
 : assign doer ' , does> @ ( left right w ) >r
-  Result :>W W>A, dup Result :hal# lea, W<>A, \ A='left W=right
-  Result :hal# r> execute A) !, Result :W ;
+  Result :?>tmp over Result :hal# lea, W>A, ( res-w rightop )
+  over Result :>W r> execute A) !, ;
 assign _=, drop    assign _+=, +,
 assign _*=, *,     assign _/=, /,      assign _%=, %,
 assign _&=, and,   assign _^=, xor,    assign _|=, or,
-
-\ TODO: deduplicate
-: rassign doer ' , does> @ ( left right w ) >r
-  Result :>W W>A, dup Result :hal# lea, W<>A, \ A='left W=right
-  Result :hal# dup @!, r> execute A) !, Result :W ;
-rassign _-=, -,    rassign _/=, /,     rassign _%=, %,
-rassign _<<=, <<,  rassign _>>=, >>,
+assign _-=, -,     assign _/=, /,      assign _%=, %,
+assign _<<=, <<,   assign _>>=, >>,
 
 \ Our implementation of "x ? y : z" suffers a significant limitation because
 \ we're single pass: by the time _? is called, it's possible that code
diff --git a/fs/comp/c/expr.fs b/fs/comp/c/expr.fs
@@ -34,6 +34,12 @@ struct[ Result
   : :isW? ( self -- f ) type W = ;
   : :const# dup :isconst? _assert arg ;
   : :>PS :>W dup, PS+ ;
+  \ When we need semi-temporary space, PS is the way to go, but it's a bit less
+  \ efficient than static storage. Sometimes, we need very short term storage.
+  \ This temporary space if for that. But it has to be used immediately.
+  create _tmp 0 ,
+  \ Free up W by sending it to _tmp (if needed).
+  : :?>tmp ( self -- halop ) dup :isW? if drop _tmp m) dup !, else :hal# then ;
 ]struct
 
 BOPSCNT wordtbl _tbl ( a b -- n )
diff --git a/fs/comp/c/gen.fs b/fs/comp/c/gen.fs
@@ -1,6 +1,6 @@
-\ C compiler parse+generate
+\ C compiler parse+generate main entry point
 \ In this unit, we are fed with tokens, we parse it, then we generate native
-\ code through the HAL.
+\ code through the HAL. The "cparse" word is the main entry point.
 require /sys/scratch.fs
 ?f<< /lib/str.fs
 ?f<< /lib/wordtbl.fs