diff --git a/basis/compiler/cfg/linear-scan/assignment/assignment-docs.factor b/basis/compiler/cfg/linear-scan/assignment/assignment-docs.factor
index 132e5b5816..1858fc806d 100644
--- a/basis/compiler/cfg/linear-scan/assignment/assignment-docs.factor
+++ b/basis/compiler/cfg/linear-scan/assignment/assignment-docs.factor
@@ -66,7 +66,7 @@ HELP: vreg>reg
 { $see-also lookup-spill-slot pending-interval-assoc } ;
 
 HELP: vregs>regs
-{ $values { "vregs" "a sequence of virtual registers" } { "assoc" assoc } }
+{ $values { "assoc" "an " { $link assoc } " (set) of virtual registers" } { "assoc" assoc } }
 { $description "Creates a mapping of virtual registers to registers." } ;
 
 HELP: vreg>spill-slot
diff --git a/basis/compiler/cfg/linear-scan/assignment/assignment-tests.factor b/basis/compiler/cfg/linear-scan/assignment/assignment-tests.factor
index 960d309d72..7cc7757c18 100644
--- a/basis/compiler/cfg/linear-scan/assignment/assignment-tests.factor
+++ b/basis/compiler/cfg/linear-scan/assignment/assignment-tests.factor
@@ -151,10 +151,10 @@ IN: compiler.cfg.linear-scan.assignment.tests
 ] [ bad-vreg? ] must-fail-with
 
 ! vregs>regs
-{ H{ { 44 RBX } { 33 RAX } } } [
+{ { { 33 RAX } { 44 RBX } } } [
     { { 33 int-rep 33 f } { 44 int-rep 44 f } } setup-vreg-spills
     H{ { 33 RAX } { 44 RBX } } pending-interval-assoc set
-    { 33 44 } vregs>regs
+    { { 33 33 } { 44 44 } } vregs>regs
 ] unit-test
 
 
diff --git a/basis/compiler/cfg/linear-scan/assignment/assignment.factor b/basis/compiler/cfg/linear-scan/assignment/assignment.factor
index bd379b8d25..9143a0b056 100644
--- a/basis/compiler/cfg/linear-scan/assignment/assignment.factor
+++ b/basis/compiler/cfg/linear-scan/assignment/assignment.factor
@@ -35,8 +35,8 @@ ERROR: not-spilled-error vreg ;
     dup vreg>reg dup spill-slot?
     [ nip ] [ drop leader not-spilled-error ] if ;
 
-: vregs>regs ( vregs -- assoc )
-    [ dup vreg>reg ] H{ } map>assoc ;
+: vregs>regs ( assoc -- assoc' )
+    [ vreg>reg ] assoc-map ;
 
 SYMBOL: unhandled-intervals
 
@@ -46,7 +46,7 @@ SYMBOL: machine-live-ins
     machine-live-ins get at ;
 
 : compute-live-in ( bb -- )
-    [ live-in keys vregs>regs ] keep machine-live-ins get set-at ;
+    [ live-in vregs>regs ] keep machine-live-ins get set-at ;
 
 SYMBOL: machine-edge-live-ins
 
@@ -54,7 +54,7 @@ SYMBOL: machine-edge-live-ins
     machine-edge-live-ins get at at ;
 
 : compute-edge-live-in ( bb -- )
-    [ edge-live-ins get at [ keys vregs>regs ] assoc-map ] keep
+    [ edge-live-ins get at [ vregs>regs ] assoc-map ] keep
     machine-edge-live-ins get set-at ;
 
 SYMBOL: machine-live-outs
@@ -63,7 +63,7 @@ SYMBOL: machine-live-outs
     machine-live-outs get at ;
 
 : compute-live-out ( bb -- )
-    [ live-out keys vregs>regs ] keep machine-live-outs get set-at ;
+    [ live-out vregs>regs ] keep machine-live-outs get set-at ;
 
 : insert-spill ( live-interval -- )
     [ reg>> ] [ spill-rep>> ] [ spill-to>> ] tri ##spill, ;