compiler.cfg.stacks.vacant: more docs and removed usage of byte-arrays

basis/compiler/cfg/stacks/vacant/vacant-docs.factor

@@ -1,4 +1,4 @@
-USING: help.markup help.syntax sequences strings ;
+USING: compiler.cfg.instructions help.markup help.syntax sequences strings ;
 IN: compiler.cfg.stacks.vacant
 
 ARTICLE: "compiler.cfg.stacks.vacant" "Uninitialized/overinitialized stack location analysis"
@@ -12,4 +12,21 @@ ARTICLE: "compiler.cfg.stacks.vacant" "Uninitialized/overinitialized stack locat
 }
 "The GC check runs before stack locations 0 and 1 have been initialized, and so the GC needs to scrub them so that they don't get traced. This is achieved by computing uninitialized locations with a dataflow analysis, and recording the information in GC maps. The scrub_contexts() method on vm/gc.cpp reads this information from GC maps and performs the scrubbing." ;
 
+HELP: initial-state
+{ $description "Initially the stack bottom is at 0 for both the data and retain stacks and no replaces have been registered." } ;
+
+HELP: vacant>bit-pattern
+{ $values
+  { "vacant" "sequence of uninitialized stack locations" }
+  { "bit-pattern" "sequence of 1:s and 0:s" }
+}
+{ $description "Converts a sequence of uninitialized stack locations to the pattern of 1:s and 0:s that can be put in the " { $slot "scrub-d" } " and " { $slot "scrub-r" } " slots of a " { $link gc-map } "." }
+{ $examples
+  { $example
+    "USING: compiler.cfg.stacks.vacant prettyprint ;"
+    "{ 0 1 3 } vacant>bit-pattern ."
+    "{ 0 0 1 0 }"
+  }
+} ;
+
 ABOUT: "compiler.cfg.stacks.vacant"

basis/compiler/cfg/stacks/vacant/vacant-tests.factor

@@ -1,7 +1,7 @@
 USING: accessors arrays assocs compiler.cfg
 compiler.cfg.dataflow-analysis.private compiler.cfg.instructions
-compiler.cfg.registers compiler.cfg.stacks.vacant kernel math sequences
-sorting tools.test vectors ;
+compiler.cfg.linearization compiler.cfg.registers compiler.cfg.stacks.vacant
+kernel math sequences sorting tools.test vectors ;
 IN: compiler.cfg.stacks.vacant.tests
 
 ! Utils
@@ -72,7 +72,7 @@ IN: compiler.cfg.stacks.vacant.tests
 ! [
 !     V{
 !         T{ ##replace { src 10 } { loc D -1 } }
-!         T{ ##alien-invoke { gc-map T{ gc-map { scrub-d B{ } } } } }
+!         T{ ##alien-invoke { gc-map T{ gc-map { scrub-d { } } } } }
 !         T{ ##peek { dst 0 } { loc D -1 } }
 !     } create-cfg
 !     compute-vacant-sets
@@ -82,7 +82,7 @@ IN: compiler.cfg.stacks.vacant.tests
 { { -1 { -1 } } } [
     V{
         T{ ##replace { src 10 } { loc D 0 } }
-        T{ ##alien-invoke { gc-map T{ gc-map { scrub-d B{ } } } } }
+        T{ ##alien-invoke { gc-map T{ gc-map { scrub-d { } } } } }
         T{ ##inc-d f -1 }
         T{ ##peek { dst 0 } { loc D -1 } }
     } create-cfg output-stack-map first
@@ -92,14 +92,14 @@ IN: compiler.cfg.stacks.vacant.tests
 ! [
 !     V{
 !         T{ ##inc-d f 1 }
-!         T{ ##alien-invoke { gc-map T{ gc-map { scrub-d B{ } } } } }
+!         T{ ##alien-invoke { gc-map T{ gc-map { scrub-d { } } } } }
 !         T{ ##peek { dst 0 } { loc D 0 } }
 !     } create-cfg
 !     compute-vacant-sets
 ! ] [ vacant-peek? ] must-fail-with
 
 ! visit-insn should set the gc info.
-{ B{ 0 0 } B{ } } [
+{ { 0 0 } { } } [
     { { 2 { } } { 0 { } } }
     T{ ##alien-invoke { gc-map T{ gc-map } } }
     [ visit-insn drop ] keep gc-map>> [ scrub-d>> ] [ scrub-r>> ] bi
@@ -213,7 +213,7 @@ IN: compiler.cfg.stacks.vacant.tests
 
                 T{ ##inc-d f -3 }
                 T{ ##peek { dst 0 } { loc D -3 } }
-                T{ ##alien-invoke { gc-map T{ gc-map { scrub-d B{ } } } } }
+                T{ ##alien-invoke { gc-map T{ gc-map { scrub-d { } } } } }
             }
         }
     } [ over create-block ] assoc-map dup

basis/compiler/cfg/stacks/vacant/vacant.factor

@@ -1,4 +1,4 @@
-USING: accessors arrays byte-arrays compiler.cfg.dataflow-analysis
+USING: accessors arrays compiler.cfg.dataflow-analysis
 compiler.cfg.instructions compiler.cfg.registers fry kernel math math.order
 sequences sets ;
 IN: compiler.cfg.stacks.vacant
@@ -20,19 +20,17 @@ IN: compiler.cfg.stacks.vacant
 : stack>vacant ( stack -- seq )
     first2 [ 0 max iota ] dip diff ;
 
-: vacant>byte-array ( seq -- ba )
-    [ B{ } ] [
+: vacant>bit-pattern ( vacant --  bit-pattern )
+    [ { } ] [
         dup supremum 1 + 1 <array>
-        [ '[ _ 0 -rot set-nth ] each ] keep >byte-array
+        [ '[ _ 0 -rot set-nth ] each ] keep
     ] if-empty ;
 
 ! Operations on the analysis state
 : state>gc-map ( state -- pair )
-    [ stack>vacant vacant>byte-array ] map ;
+    [ stack>vacant vacant>bit-pattern ] map ;
 
-! Stack bottom is 0 for d and r and no replaces.
-: initial-state ( -- state )
-    { { 0 { } } { 0 { } } } ;
+CONSTANT: initial-state { { 0 { } } { 0 { } } }
 
 : insn>gc-map ( insn -- pair )
     gc-map>> [ scrub-d>> ] [ scrub-r>> ] bi 2array ;