diff --git a/basis/compiler/cfg/instructions/instructions.factor b/basis/compiler/cfg/instructions/instructions.factor
index 1a1b2fd65c..abbb86cb16 100644
--- a/basis/compiler/cfg/instructions/instructions.factor
+++ b/basis/compiler/cfg/instructions/instructions.factor
@@ -261,4 +261,3 @@ INSN: _reload dst class n ;
 INSN: _copy dst src class ;
 INSN: _spill-counts counts ;
 
-SYMBOL: spill-temp
diff --git a/basis/compiler/cfg/linear-scan/linear-scan-tests.factor b/basis/compiler/cfg/linear-scan/linear-scan-tests.factor
index 63d31dfb4e..e3cd9e105f 100644
--- a/basis/compiler/cfg/linear-scan/linear-scan-tests.factor
+++ b/basis/compiler/cfg/linear-scan/linear-scan-tests.factor
@@ -206,6 +206,56 @@ check-assignment? on
     } 5 split-before-use [ f >>split-next ] bi@
 ] unit-test
 
+[
+    T{ live-interval
+        { vreg T{ vreg { reg-class int-regs } { n 1 } } }
+        { start 0 }
+        { end 4 }
+        { uses V{ 0 1 4 } }
+        { ranges V{ T{ live-range f 0 4 } } }
+    }
+    T{ live-interval
+        { vreg T{ vreg { reg-class int-regs } { n 1 } } }
+        { start 5 }
+        { end 10 }
+        { uses V{ 5 10 } }
+        { ranges V{ T{ live-range f 5 10 } } }
+    }
+] [
+    T{ live-interval
+       { vreg T{ vreg { reg-class int-regs } { n 1 } } }
+       { start 0 }
+       { end 10 }
+       { uses V{ 0 1 10 } }
+       { ranges V{ T{ live-range f 0 10 } } }
+    } 5 split-before-use [ f >>split-next ] bi@
+] unit-test
+
+[
+    T{ live-interval
+        { vreg T{ vreg { reg-class int-regs } { n 1 } } }
+        { start 0 }
+        { end 4 }
+        { uses V{ 0 1 4 } }
+        { ranges V{ T{ live-range f 0 4 } } }
+    }
+    T{ live-interval
+        { vreg T{ vreg { reg-class int-regs } { n 1 } } }
+        { start 5 }
+        { end 10 }
+        { uses V{ 5 10 } }
+        { ranges V{ T{ live-range f 5 10 } } }
+    }
+] [
+    T{ live-interval
+       { vreg T{ vreg { reg-class int-regs } { n 1 } } }
+       { start 0 }
+       { end 10 }
+       { uses V{ 0 1 4 5 10 } }
+       { ranges V{ T{ live-range f 0 10 } } }
+    } 5 split-before-use [ f >>split-next ] bi@
+] unit-test
+
 [
     T{ live-interval
         { vreg T{ vreg { reg-class int-regs } { n 1 } } }
@@ -1858,6 +1908,8 @@ test-diamond
 
 [ _spill ] [ 3 get instructions>> second class ] unit-test
 
+[ f ] [ 3 get instructions>> [ _reload? ] any? ] unit-test
+
 [ _reload ] [ 4 get instructions>> first class ] unit-test
 
 ! Resolve pass
@@ -1975,4 +2027,77 @@ V{
 [ V{ 3 2 1 } ] [ 9 get instructions>> [ _reload? ] filter [ n>> ] map ] unit-test
 
 ! Resolve pass should insert this
-[ _reload ] [ 5 get instructions>> first class ] unit-test
\ No newline at end of file
+[ _reload ] [ 5 get instructions>> first class ] unit-test
+
+! Some random bug
+V{
+    T{ ##peek f V int-regs 1 D 1 }
+    T{ ##peek f V int-regs 2 D 2 }
+    T{ ##replace f V int-regs 1 D 1 }
+    T{ ##replace f V int-regs 2 D 2 }
+    T{ ##peek f V int-regs 3 D 0 }
+    T{ ##peek f V int-regs 0 D 0 }
+    T{ ##branch }
+} 0 test-bb
+
+V{ T{ ##branch } } 1 test-bb
+
+V{
+    T{ ##peek f V int-regs 1 D 1 }
+    T{ ##peek f V int-regs 2 D 2 }
+    T{ ##replace f V int-regs 3 D 3 }
+    T{ ##replace f V int-regs 1 D 1 }
+    T{ ##replace f V int-regs 2 D 2 }
+    T{ ##replace f V int-regs 0 D 3 }
+    T{ ##branch }
+} 2 test-bb
+
+V{ T{ ##branch } } 3 test-bb
+
+V{
+    T{ ##return }
+} 4 test-bb
+
+test-diamond
+
+[ ] [ { 1 2 } test-linear-scan-on-cfg ] unit-test
+
+! Spilling an interval immediately after its activated;
+! and the interval does not have a use at the activation point
+V{
+    T{ ##peek f V int-regs 1 D 1 }
+    T{ ##peek f V int-regs 2 D 2 }
+    T{ ##replace f V int-regs 1 D 1 }
+    T{ ##replace f V int-regs 2 D 2 }
+    T{ ##peek f V int-regs 0 D 0 }
+    T{ ##branch }
+} 0 test-bb
+
+V{ T{ ##branch } } 1 test-bb
+
+V{
+    T{ ##peek f V int-regs 1 D 1 }
+    T{ ##branch }
+} 2 test-bb
+
+V{
+    T{ ##replace f V int-regs 1 D 1 }
+    T{ ##peek f V int-regs 2 D 2 }
+    T{ ##replace f V int-regs 2 D 2 }
+    T{ ##branch }
+} 3 test-bb
+
+V{ T{ ##branch } } 4 test-bb
+
+V{
+    T{ ##replace f V int-regs 0 D 0 }
+    T{ ##return }
+} 5 test-bb
+
+1 get 1vector 0 get (>>successors)
+2 get 4 get V{ } 2sequence 1 get (>>successors)
+5 get 1vector 4 get (>>successors)
+3 get 1vector 2 get (>>successors)
+5 get 1vector 3 get (>>successors)
+
+[ ] [ { 1 2 } test-linear-scan-on-cfg ] unit-test
diff --git a/basis/compiler/cfg/linear-scan/resolve/resolve-tests.factor b/basis/compiler/cfg/linear-scan/resolve/resolve-tests.factor
index 4c27e5c4eb..7e308cf231 100644
--- a/basis/compiler/cfg/linear-scan/resolve/resolve-tests.factor
+++ b/basis/compiler/cfg/linear-scan/resolve/resolve-tests.factor
@@ -3,6 +3,7 @@ compiler.cfg.debugger compiler.cfg.instructions
 compiler.cfg.linear-scan.debugger
 compiler.cfg.linear-scan.live-intervals
 compiler.cfg.linear-scan.numbering
+compiler.cfg.linear-scan.allocation.state
 compiler.cfg.linear-scan.resolve compiler.cfg.predecessors
 compiler.cfg.registers compiler.cfg.rpo cpu.architecture kernel
 namespaces tools.test vectors ;
@@ -12,15 +13,18 @@ IN: compiler.cfg.linear-scan.resolve.tests
     { 3 4 } V{ 1 2 } clone [ { 5 6 } 3append-here ] keep >array
 ] unit-test
 
+H{ { int-regs 10 } { float-regs 20 } } clone spill-counts set
+H{ } clone spill-temps set
+
 [
     {
         T{ _copy { dst 5 } { src 4 } { class int-regs } }
-        T{ _spill { src 1 } { class int-regs } { n spill-temp } }
+        T{ _spill { src 1 } { class int-regs } { n 10 } }
         T{ _copy { dst 1 } { src 0 } { class int-regs } }
-        T{ _reload { dst 0 } { class int-regs } { n spill-temp } }
-        T{ _spill { src 1 } { class float-regs } { n spill-temp } }
+        T{ _reload { dst 0 } { class int-regs } { n 10 } }
+        T{ _spill { src 1 } { class float-regs } { n 20 } }
         T{ _copy { dst 1 } { src 0 } { class float-regs } }
-        T{ _reload { dst 0 } { class float-regs } { n spill-temp } }
+        T{ _reload { dst 0 } { class float-regs } { n 20 } }
     }
 ] [
     {
@@ -34,10 +38,10 @@ IN: compiler.cfg.linear-scan.resolve.tests
 
 [
     {
-        T{ _spill { src 2 } { class int-regs } { n spill-temp } }
+        T{ _spill { src 2 } { class int-regs } { n 10 } }
         T{ _copy { dst 2 } { src 1 } { class int-regs } }
         T{ _copy { dst 1 } { src 0 } { class int-regs } }
-        T{ _reload { dst 0 } { class int-regs } { n spill-temp } }
+        T{ _reload { dst 0 } { class int-regs } { n 10 } }
     }
 ] [
     {
@@ -49,10 +53,10 @@ IN: compiler.cfg.linear-scan.resolve.tests
 
 [
     {
-        T{ _spill { src 0 } { class int-regs } { n spill-temp } }
+        T{ _spill { src 0 } { class int-regs } { n 10 } }
         T{ _copy { dst 0 } { src 2 } { class int-regs } }
         T{ _copy { dst 2 } { src 1 } { class int-regs } }
-        T{ _reload { dst 1 } { class int-regs } { n spill-temp } }
+        T{ _reload { dst 1 } { class int-regs } { n 10 } }
     }
 ] [
     {
@@ -113,10 +117,10 @@ IN: compiler.cfg.linear-scan.resolve.tests
     {
         T{ _copy { dst 1 } { src 0 } { class int-regs } }
         T{ _copy { dst 2 } { src 0 } { class int-regs } }
-        T{ _spill { src 4 } { class int-regs } { n spill-temp } }
+        T{ _spill { src 4 } { class int-regs } { n 10 } }
         T{ _copy { dst 4 } { src 0 } { class int-regs } }
         T{ _copy { dst 0 } { src 3 } { class int-regs } }
-        T{ _reload { dst 3 } { class int-regs } { n spill-temp } }
+        T{ _reload { dst 3 } { class int-regs } { n 10 } }
     }
 ] [
     {
@@ -133,10 +137,10 @@ IN: compiler.cfg.linear-scan.resolve.tests
         T{ _copy { dst 2 } { src 0 } { class int-regs } }
         T{ _copy { dst 9 } { src 1 } { class int-regs } }
         T{ _copy { dst 1 } { src 0 } { class int-regs } }
-        T{ _spill { src 4 } { class int-regs } { n spill-temp } }
+        T{ _spill { src 4 } { class int-regs } { n 10 } }
         T{ _copy { dst 4 } { src 0 } { class int-regs } }
         T{ _copy { dst 0 } { src 3 } { class int-regs } }
-        T{ _reload { dst 3 } { class int-regs } { n spill-temp } }
+        T{ _reload { dst 3 } { class int-regs } { n 10 } }
     }
 ] [
     {
diff --git a/basis/compiler/cfg/linear-scan/resolve/resolve.factor b/basis/compiler/cfg/linear-scan/resolve/resolve.factor
index 951e727375..196d8e439f 100644
--- a/basis/compiler/cfg/linear-scan/resolve/resolve.factor
+++ b/basis/compiler/cfg/linear-scan/resolve/resolve.factor
@@ -3,10 +3,15 @@
 USING: accessors arrays assocs classes.parser classes.tuple
 combinators combinators.short-circuit fry hashtables kernel locals
 make math math.order namespaces sequences sets words parser
-compiler.cfg.instructions compiler.cfg.linear-scan.assignment
-compiler.cfg.liveness ;
+compiler.cfg.instructions compiler.cfg.linear-scan.allocation.state
+compiler.cfg.linear-scan.assignment compiler.cfg.liveness ;
 IN: compiler.cfg.linear-scan.resolve
 
+SYMBOL: spill-temps
+
+: spill-temp ( reg-class -- n )
+    spill-temps get [ next-spill-slot ] cache ;
+
 <<
 
 TUPLE: operation from to reg-class ;
@@ -116,11 +121,15 @@ ERROR: resolve-error ;
 
 : break-cycle-n ( operations -- operations' )
     split-cycle [
-        [ from>> spill-temp <spill-slot> ]
-        [ reg-class>> ] bi \ register->memory boa
+        [ from>> ]
+        [ reg-class>> spill-temp <spill-slot> ]
+        [ reg-class>> ]
+        tri \ register->memory boa
     ] [
-        [ to>> spill-temp <spill-slot> swap ]
-        [ reg-class>> ] bi \ memory->register boa
+        [ reg-class>> spill-temp <spill-slot> ]
+        [ to>> ]
+        [ reg-class>> ]
+        tri \ memory->register boa
     ] bi [ 1array ] bi@ surround ;
 
 : break-cycle ( operations -- operations' )
@@ -197,4 +206,5 @@ ERROR: resolve-error ;
     dup successors>> [ resolve-edge-data-flow ] with each ;
 
 : resolve-data-flow ( rpo -- )
+    H{ } clone spill-temps set
     [ resolve-block-data-flow ] each ;