compiler.cfg.scheduling: remove old scheduling test code, adding a better way of testing scheduling

basis/compiler/cfg/scheduling/scheduling-tests.factor

@@ -1,16 +1,9 @@
 USING: compiler.cfg.scheduling compiler.cfg.instructions
-vocabs.loader namespaces tools.test arrays kernel ;
+vocabs.loader namespaces tools.test arrays kernel random
+words compiler.units ;
 IN: compiler.cfg.scheduling.tests
 
-! Recompile compiler.cfg.scheduling with extra tests,
-! and see if any errors come up. Back when there were
-! errors of this kind, they always surfaced this way.
-
-t check-scheduling? [
-    [ ] [ "compiler.cfg.scheduling" reload ] unit-test
-    [ ] [ "compiler.cfg.dependence" reload ] unit-test
-] with-variable
-
+! Test split-3-ways
 [
     { }
     { }

basis/compiler/cfg/scheduling/scheduling.factor

@@ -80,40 +80,6 @@ conditional-branch-insn
         [ (reorder) ] V{ } make reverse
     ] dip 3append ;
 
-ERROR: not-all-instructions-were-scheduled old-bb new-bb ;
-
-SYMBOL: check-scheduling?
-f check-scheduling? set-global
-
-:: check-instructions ( new-bb old-bb -- )
-    new-bb old-bb [ instructions>> ] bi@
-    [ [ length ] bi@ = ] [ [ unique ] bi@ = ] 2bi and
-    [ old-bb new-bb not-all-instructions-were-scheduled ] unless ;
-
-ERROR: definition-after-usage vregs old-bb new-bb ;
-
-:: check-usages ( new-bb old-bb -- )
-    HS{ } clone :> useds
-    new-bb instructions>> split-3-ways drop nip
-    [| insn |
-        insn uses-vregs [ useds adjoin ] each
-        insn defs-vregs :> defs-vregs
-        defs-vregs useds intersects?
-        [ defs-vregs old-bb new-bb definition-after-usage ] when
-    ] each ;
-
-: check-scheduling ( new-bb old-bb -- )
-    [ check-instructions ] [ check-usages ] 2bi ;
-
-: with-scheduling-check ( bb quot: ( bb -- ) -- )
-    check-scheduling? get [
-        over dup clone
-        [ call( bb -- ) ] 2dip
-        check-scheduling
-    ] [
-        call( bb -- )
-    ] if ; inline
-
 : number-insns ( insns -- )
     [ >>insn# drop ] each-index ;
 
@@ -121,13 +87,11 @@ ERROR: definition-after-usage vregs old-bb new-bb ;
     [ f >>insn# drop ] each ;
 
 : schedule-block ( bb -- )
-    [
     [
         [ number-insns ]
         [ reorder ]
         [ clear-numbers ] tri
-        ] change-instructions drop
-    ] with-scheduling-check ;
+    ] change-instructions drop ;
 
 : schedule-instructions ( cfg -- cfg' )
     dup [