z80: make exec routine a wee bit tighter

1 whole byte!

blk/287

@@ -1,8 +1,9 @@
 lblexec BSET L1 FSET ( B284 ) L2 FSET ( B286 )
     ( DE -> wordref )
-    LDA(DE), DE INCd,
+    LDA(DE), DE INCd, EXDEHL, ( HL points to PFA )
-    A ORr, IFZ, EXDEHL, JP(HL), THEN,
+    A ORr, IFZ, JP(HL), THEN,
-    A DECr, JRZ, L1 FWR ( compiled B289 )
+    A DECr, ( compiled? ) IFNZ, ( no )
-    ( cell or does. push PFA ) DE PUSH,
+    ( cell or does. push PFA ) HL PUSH,
     A DECr, JRZ, lblnext BWR ( cell )
-    ( continue to does )
+    HL INCd, HL INCd, LDDE(HL), EXDEHL, ( does )
+    THEN, ( continue to compiledWord )

blk/288

@@ -1,12 +0,0 @@
-( does. The word was spawned from a definition word that has a
-  DOES>. PFA+2 (right after the actual cell) is a link to the
-  slot right after that DOES>. Therefore, what we need to do
-  push the cell addr like a regular cell, then follow the
-  linkfrom the PFA, and then continue as a regular
-  compiledWord. )
-    EXDEHL,
-    HL INCd, HL INCd,
-    E (HL) LDrr,
-    HL INCd,
-    D (HL) LDrr,
-    ( continue to compiledWord )

blk/289

@@ -1,11 +1,9 @@
-( compiled word ) L1 FSET ( execute B301 )
 ( 1. Push current IP to RS
   2. Set new IP to the second atom of the list
   3. Execute the first atom of the list. )
     IX INCd, IX INCd,
     0 IX+ C LDIXYr,
     1 IX+ B LDIXYr,
-    EXDEHL,          ( HL points to PFA )
 ( While we inc, dereference into DE for execute call later. )
     LDDE(HL),
     HL INCd,