diff --git a/src/test/ref/operator-byte0.asm b/src/test/ref/operator-byte0.asm
new file mode 100644
index 000000000..3e8e6baf0
--- /dev/null
+++ b/src/test/ref/operator-byte0.asm
@@ -0,0 +1,93 @@
+// Test operator BYTE0()
+  // Commodore 64 PRG executable file
+.file [name="operator-byte0.prg", type="prg", segments="Program"]
+.segmentdef Program [segments="Basic, Code, Data"]
+.segmentdef Basic [start=$0801]
+.segmentdef Code [start=$80d]
+.segmentdef Data [startAfter="Code"]
+.segment Basic
+:BasicUpstart(main)
+.segment Code
+main: {
+    .label SCREEN = $400
+    .label bu = 2
+    .label bs = 3
+    .label wu = 4
+    .label ws = 6
+    .label du = 8
+    .label ds = $c
+    .label ptr = $10
+    // bu = 7
+    lda #7
+    sta.z bu
+    // bs = 7
+    sta.z bs
+    // wu = 20000
+    lda #<$4e20
+    sta.z wu
+    lda #>$4e20
+    sta.z wu+1
+    // ws = -177
+    lda #<-$b1
+    sta.z ws
+    lda #>-$b1
+    sta.z ws+1
+    // du = 2000000
+    lda #<$1e8480
+    sta.z du
+    lda #>$1e8480
+    sta.z du+1
+    lda #<$1e8480>>$10
+    sta.z du+2
+    lda #>$1e8480>>$10
+    sta.z du+3
+    // ds = -3777777
+    lda #<-$39a4f1
+    sta.z ds
+    lda #>-$39a4f1
+    sta.z ds+1
+    lda #<-$39a4f1>>$10
+    sta.z ds+2
+    lda #>-$39a4f1>>$10
+    sta.z ds+3
+    // ptr = 0x0000
+    lda #<0
+    sta.z ptr
+    sta.z ptr+1
+    // SCREEN[i++] = BYTE0(17)
+    lda #<($11)
+    sta SCREEN
+    // SCREEN[i++] = BYTE0(377)
+    lda #<($179)
+    sta SCREEN+1
+    // BYTE0(bu)
+    lda.z bu
+    // SCREEN[i++] = BYTE0(bu)
+    sta SCREEN+2
+    // BYTE0(bs)
+    lda.z bs
+    // SCREEN[i++] = BYTE0(bs)
+    sta SCREEN+3
+    // BYTE0(wu)
+    lda.z wu
+    // SCREEN[i++] = BYTE0(wu)
+    sta SCREEN+4
+    // BYTE0(ws)
+    lda.z ws
+    // SCREEN[i++] = BYTE0(ws)
+    sta SCREEN+5
+    // BYTE0(du)
+    lda.z du
+    // SCREEN[i++] = BYTE0(du)
+    sta SCREEN+6
+    // BYTE0(ds)
+    lda.z ds
+    // SCREEN[i++] = BYTE0(ds)
+    sta SCREEN+7
+    // BYTE0(ptr)
+    lda.z ptr
+    // SCREEN[i++] = BYTE0(ptr)
+    sta SCREEN+8
+    // }
+    rts
+}
diff --git a/src/test/ref/operator-byte0.cfg b/src/test/ref/operator-byte0.cfg
new file mode 100644
index 000000000..11ec53640
--- /dev/null
+++ b/src/test/ref/operator-byte0.cfg
@@ -0,0 +1,30 @@
+
+void main()
+main: scope:[main]  from
+  [0] main::bu = 7
+  [1] main::bs = 7
+  [2] main::wu = $4e20
+  [3] main::ws = -$b1
+  [4] main::du = $1e8480
+  [5] main::ds = -$39a4f1
+  [6] main::ptr = (byte*) 0
+  [7] *main::SCREEN = <$11
+  [8] *(main::SCREEN+1) = <$179
+  [9] main::$2 = < main::bu
+  [10] *(main::SCREEN+2) = main::$2
+  [11] main::$3 = < main::bs
+  [12] *(main::SCREEN+3) = main::$3
+  [13] main::$4 = < main::wu
+  [14] *(main::SCREEN+4) = main::$4
+  [15] main::$5 = < main::ws
+  [16] *(main::SCREEN+5) = main::$5
+  [17] main::$6 = < main::du
+  [18] *(main::SCREEN+6) = main::$6
+  [19] main::$7 = < main::ds
+  [20] *(main::SCREEN+7) = main::$7
+  [21] main::$8 = < main::ptr
+  [22] *(main::SCREEN+8) = main::$8
+  to:main::@return
+main::@return: scope:[main]  from main
+  [23] return 
+  to:@return
diff --git a/src/test/ref/operator-byte0.log b/src/test/ref/operator-byte0.log
new file mode 100644
index 000000000..4027969a8
--- /dev/null
+++ b/src/test/ref/operator-byte0.log
@@ -0,0 +1,609 @@
+
+CONTROL FLOW GRAPH SSA
+
+void main()
+main: scope:[main]  from __start
+  main::bu = 7
+  main::bs = 7
+  main::wu = $4e20
+  main::ws = -$b1
+  main::du = $1e8480
+  main::ds = -$39a4f1
+  main::ptr = (byte*)0
+  main::i#0 = 0
+  main::$0 = < $11
+  main::SCREEN[main::i#0] = main::$0
+  main::i#1 = ++ main::i#0
+  main::$1 = < $179
+  main::SCREEN[main::i#1] = main::$1
+  main::i#2 = ++ main::i#1
+  main::$2 = < main::bu
+  main::SCREEN[main::i#2] = main::$2
+  main::i#3 = ++ main::i#2
+  main::$3 = < main::bs
+  main::SCREEN[main::i#3] = main::$3
+  main::i#4 = ++ main::i#3
+  main::$4 = < main::wu
+  main::SCREEN[main::i#4] = main::$4
+  main::i#5 = ++ main::i#4
+  main::$5 = < main::ws
+  main::SCREEN[main::i#5] = main::$5
+  main::i#6 = ++ main::i#5
+  main::$6 = < main::du
+  main::SCREEN[main::i#6] = main::$6
+  main::i#7 = ++ main::i#6
+  main::$7 = < main::ds
+  main::SCREEN[main::i#7] = main::$7
+  main::i#8 = ++ main::i#7
+  main::$8 = < main::ptr
+  main::SCREEN[main::i#8] = main::$8
+  main::i#9 = ++ main::i#8
+  to:main::@return
+main::@return: scope:[main]  from main
+  return 
+  to:@return
+
+void __start()
+__start: scope:[__start]  from
+  call main 
+  to:__start::@1
+__start::@1: scope:[__start]  from __start
+  to:__start::@return
+__start::@return: scope:[__start]  from __start::@1
+  return 
+  to:@return
+
+SYMBOL TABLE SSA
+void __start()
+void main()
+byte~ main::$0
+byte~ main::$1
+byte~ main::$2
+byte~ main::$3
+byte~ main::$4
+byte~ main::$5
+byte~ main::$6
+byte~ main::$7
+byte~ main::$8
+const nomodify byte* main::SCREEN = (byte*)$400
+volatile signed byte main::bs loadstore
+volatile byte main::bu loadstore
+volatile signed dword main::ds loadstore
+volatile dword main::du loadstore
+byte main::i
+byte main::i#0
+byte main::i#1
+byte main::i#2
+byte main::i#3
+byte main::i#4
+byte main::i#5
+byte main::i#6
+byte main::i#7
+byte main::i#8
+byte main::i#9
+volatile byte* main::ptr loadstore
+volatile signed word main::ws loadstore
+volatile word main::wu loadstore
+
+Simplifying constant pointer cast (byte*) 1024
+Simplifying constant pointer cast (byte*) 0
+Successful SSA optimization PassNCastSimplification
+Constant right-side identified [8] main::$0 = < $11
+Constant right-side identified [11] main::$1 = < $179
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#0 = 0
+Constant main::$0 = <$11
+Constant main::$1 = <$179
+Successful SSA optimization Pass2ConstantIdentification
+Simplifying expression containing zero main::SCREEN in [9] main::SCREEN[main::i#0] = main::$0
+Successful SSA optimization PassNSimplifyExpressionWithZero
+Eliminating unused variable main::i#9 and assignment [31] main::i#9 = ++ main::i#8
+Successful SSA optimization PassNEliminateUnusedVars
+Removing unused procedure __start
+Removing unused procedure block __start
+Removing unused procedure block __start::@1
+Removing unused procedure block __start::@return
+Successful SSA optimization PassNEliminateEmptyStart
+Constant right-side identified [8] main::i#1 = ++ main::i#0
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#1 = ++main::i#0
+Successful SSA optimization Pass2ConstantIdentification
+Constant right-side identified [9] main::i#2 = ++ main::i#1
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#2 = ++main::i#1
+Successful SSA optimization Pass2ConstantIdentification
+Constant right-side identified [11] main::i#3 = ++ main::i#2
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#3 = ++main::i#2
+Successful SSA optimization Pass2ConstantIdentification
+Constant right-side identified [13] main::i#4 = ++ main::i#3
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#4 = ++main::i#3
+Successful SSA optimization Pass2ConstantIdentification
+Constant right-side identified [15] main::i#5 = ++ main::i#4
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#5 = ++main::i#4
+Successful SSA optimization Pass2ConstantIdentification
+Constant right-side identified [17] main::i#6 = ++ main::i#5
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#6 = ++main::i#5
+Successful SSA optimization Pass2ConstantIdentification
+Constant right-side identified [19] main::i#7 = ++ main::i#6
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#7 = ++main::i#6
+Successful SSA optimization Pass2ConstantIdentification
+Constant right-side identified [21] main::i#8 = ++ main::i#7
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#8 = ++main::i#7
+Successful SSA optimization Pass2ConstantIdentification
+Inlining constant with different constant siblings main::i#0
+Inlining constant with different constant siblings main::i#1
+Inlining constant with different constant siblings main::i#2
+Inlining constant with different constant siblings main::i#3
+Inlining constant with different constant siblings main::i#4
+Inlining constant with different constant siblings main::i#5
+Inlining constant with different constant siblings main::i#6
+Inlining constant with different constant siblings main::i#7
+Inlining constant with different constant siblings main::i#8
+Constant inlined main::i#8 = ++++++++++++++++0
+Constant inlined main::i#7 = ++++++++++++++0
+Constant inlined main::$1 = <$179
+Constant inlined main::i#4 = ++++++++0
+Constant inlined main::i#3 = ++++++0
+Constant inlined main::i#6 = ++++++++++++0
+Constant inlined main::$0 = <$11
+Constant inlined main::i#5 = ++++++++++0
+Constant inlined main::i#0 = 0
+Constant inlined main::i#2 = ++++0
+Constant inlined main::i#1 = ++0
+Successful SSA optimization Pass2ConstantInlining
+Consolidated array index constant in *(main::SCREEN+++0)
+Consolidated array index constant in *(main::SCREEN+++++0)
+Consolidated array index constant in *(main::SCREEN+++++++0)
+Consolidated array index constant in *(main::SCREEN+++++++++0)
+Consolidated array index constant in *(main::SCREEN+++++++++++0)
+Consolidated array index constant in *(main::SCREEN+++++++++++++0)
+Consolidated array index constant in *(main::SCREEN+++++++++++++++0)
+Consolidated array index constant in *(main::SCREEN+++++++++++++++++0)
+Successful SSA optimization Pass2ConstantAdditionElimination
+Simplifying constant integer increment ++0
+Simplifying constant integer increment ++0
+Simplifying constant integer increment ++1
+Simplifying constant integer increment ++2
+Simplifying constant integer increment ++3
+Simplifying constant integer increment ++4
+Simplifying constant integer increment ++5
+Simplifying constant integer increment ++6
+Successful SSA optimization Pass2ConstantSimplification
+Simplifying constant integer increment ++1
+Simplifying constant integer increment ++2
+Simplifying constant integer increment ++3
+Simplifying constant integer increment ++4
+Simplifying constant integer increment ++5
+Simplifying constant integer increment ++6
+Simplifying constant integer increment ++7
+Successful SSA optimization Pass2ConstantSimplification
+Finalized unsigned number type (byte) $11
+Finalized unsigned number type (word) $179
+Successful SSA optimization PassNFinalizeNumberTypeConversions
+CALL GRAPH
+
+Created 0 initial phi equivalence classes
+Coalesced down to 0 phi equivalence classes
+
+FINAL CONTROL FLOW GRAPH
+
+void main()
+main: scope:[main]  from
+  [0] main::bu = 7
+  [1] main::bs = 7
+  [2] main::wu = $4e20
+  [3] main::ws = -$b1
+  [4] main::du = $1e8480
+  [5] main::ds = -$39a4f1
+  [6] main::ptr = (byte*) 0
+  [7] *main::SCREEN = <$11
+  [8] *(main::SCREEN+1) = <$179
+  [9] main::$2 = < main::bu
+  [10] *(main::SCREEN+2) = main::$2
+  [11] main::$3 = < main::bs
+  [12] *(main::SCREEN+3) = main::$3
+  [13] main::$4 = < main::wu
+  [14] *(main::SCREEN+4) = main::$4
+  [15] main::$5 = < main::ws
+  [16] *(main::SCREEN+5) = main::$5
+  [17] main::$6 = < main::du
+  [18] *(main::SCREEN+6) = main::$6
+  [19] main::$7 = < main::ds
+  [20] *(main::SCREEN+7) = main::$7
+  [21] main::$8 = < main::ptr
+  [22] *(main::SCREEN+8) = main::$8
+  to:main::@return
+main::@return: scope:[main]  from main
+  [23] return 
+  to:@return
+
+
+VARIABLE REGISTER WEIGHTS
+void main()
+byte~ main::$2 4.0
+byte~ main::$3 4.0
+byte~ main::$4 4.0
+byte~ main::$5 4.0
+byte~ main::$6 4.0
+byte~ main::$7 4.0
+byte~ main::$8 4.0
+volatile signed byte main::bs loadstore 0.4
+volatile byte main::bu loadstore 0.4444444444444444
+volatile signed dword main::ds loadstore 0.2857142857142857
+volatile dword main::du loadstore 0.3076923076923077
+byte main::i
+volatile byte* main::ptr loadstore 0.26666666666666666
+volatile signed word main::ws loadstore 0.3333333333333333
+volatile word main::wu loadstore 0.36363636363636365
+
+Initial phi equivalence classes
+Added variable main::bu to live range equivalence class [ main::bu ]
+Added variable main::bs to live range equivalence class [ main::bs ]
+Added variable main::wu to live range equivalence class [ main::wu ]
+Added variable main::ws to live range equivalence class [ main::ws ]
+Added variable main::du to live range equivalence class [ main::du ]
+Added variable main::ds to live range equivalence class [ main::ds ]
+Added variable main::ptr to live range equivalence class [ main::ptr ]
+Added variable main::$2 to live range equivalence class [ main::$2 ]
+Added variable main::$3 to live range equivalence class [ main::$3 ]
+Added variable main::$4 to live range equivalence class [ main::$4 ]
+Added variable main::$5 to live range equivalence class [ main::$5 ]
+Added variable main::$6 to live range equivalence class [ main::$6 ]
+Added variable main::$7 to live range equivalence class [ main::$7 ]
+Added variable main::$8 to live range equivalence class [ main::$8 ]
+Complete equivalence classes
+[ main::bu ]
+[ main::bs ]
+[ main::wu ]
+[ main::ws ]
+[ main::du ]
+[ main::ds ]
+[ main::ptr ]
+[ main::$2 ]
+[ main::$3 ]
+[ main::$4 ]
+[ main::$5 ]
+[ main::$6 ]
+[ main::$7 ]
+[ main::$8 ]
+Allocated zp[1]:2 [ main::bu ]
+Allocated zp[1]:3 [ main::bs ]
+Allocated zp[2]:4 [ main::wu ]
+Allocated zp[2]:6 [ main::ws ]
+Allocated zp[4]:8 [ main::du ]
+Allocated zp[4]:12 [ main::ds ]
+Allocated zp[2]:16 [ main::ptr ]
+Allocated zp[1]:18 [ main::$2 ]
+Allocated zp[1]:19 [ main::$3 ]
+Allocated zp[1]:20 [ main::$4 ]
+Allocated zp[1]:21 [ main::$5 ]
+Allocated zp[1]:22 [ main::$6 ]
+Allocated zp[1]:23 [ main::$7 ]
+Allocated zp[1]:24 [ main::$8 ]
+REGISTER UPLIFT POTENTIAL REGISTERS
+Statement [0] main::bu = 7 [ main::bu ] (  [ main::bu ] { }  ) always clobbers reg byte a 
+Statement [1] main::bs = 7 [ main::bu main::bs ] (  [ main::bu main::bs ] { }  ) always clobbers reg byte a 
+Statement [2] main::wu = $4e20 [ main::bu main::bs main::wu ] (  [ main::bu main::bs main::wu ] { }  ) always clobbers reg byte a 
+Statement [3] main::ws = -$b1 [ main::bu main::bs main::wu main::ws ] (  [ main::bu main::bs main::wu main::ws ] { }  ) always clobbers reg byte a 
+Statement [4] main::du = $1e8480 [ main::bu main::bs main::wu main::ws main::du ] (  [ main::bu main::bs main::wu main::ws main::du ] { }  ) always clobbers reg byte a 
+Statement [5] main::ds = -$39a4f1 [ main::bu main::bs main::wu main::ws main::du main::ds ] (  [ main::bu main::bs main::wu main::ws main::du main::ds ] { }  ) always clobbers reg byte a 
+Statement [6] main::ptr = (byte*) 0 [ main::bu main::bs main::wu main::ws main::du main::ds main::ptr ] (  [ main::bu main::bs main::wu main::ws main::du main::ds main::ptr ] { }  ) always clobbers reg byte a 
+Statement [7] *main::SCREEN = <$11 [ main::bu main::bs main::wu main::ws main::du main::ds main::ptr ] (  [ main::bu main::bs main::wu main::ws main::du main::ds main::ptr ] { }  ) always clobbers reg byte a 
+Statement [8] *(main::SCREEN+1) = <$179 [ main::bu main::bs main::wu main::ws main::du main::ds main::ptr ] (  [ main::bu main::bs main::wu main::ws main::du main::ds main::ptr ] { }  ) always clobbers reg byte a 
+Statement [9] main::$2 = < main::bu [ main::bs main::wu main::ws main::du main::ds main::ptr main::$2 ] (  [ main::bs main::wu main::ws main::du main::ds main::ptr main::$2 ] { }  ) always clobbers reg byte a 
+Statement [11] main::$3 = < main::bs [ main::wu main::ws main::du main::ds main::ptr main::$3 ] (  [ main::wu main::ws main::du main::ds main::ptr main::$3 ] { }  ) always clobbers reg byte a 
+Potential registers zp[1]:2 [ main::bu ] : zp[1]:2 , 
+Potential registers zp[1]:3 [ main::bs ] : zp[1]:3 , 
+Potential registers zp[2]:4 [ main::wu ] : zp[2]:4 , 
+Potential registers zp[2]:6 [ main::ws ] : zp[2]:6 , 
+Potential registers zp[4]:8 [ main::du ] : zp[4]:8 , 
+Potential registers zp[4]:12 [ main::ds ] : zp[4]:12 , 
+Potential registers zp[2]:16 [ main::ptr ] : zp[2]:16 , 
+Potential registers zp[1]:18 [ main::$2 ] : zp[1]:18 , reg byte a , reg byte x , reg byte y , 
+Potential registers zp[1]:19 [ main::$3 ] : zp[1]:19 , reg byte a , reg byte x , reg byte y , 
+Potential registers zp[1]:20 [ main::$4 ] : zp[1]:20 , reg byte a , reg byte x , reg byte y , 
+Potential registers zp[1]:21 [ main::$5 ] : zp[1]:21 , reg byte a , reg byte x , reg byte y , 
+Potential registers zp[1]:22 [ main::$6 ] : zp[1]:22 , reg byte a , reg byte x , reg byte y , 
+Potential registers zp[1]:23 [ main::$7 ] : zp[1]:23 , reg byte a , reg byte x , reg byte y , 
+Potential registers zp[1]:24 [ main::$8 ] : zp[1]:24 , reg byte a , reg byte x , reg byte y , 
+
+REGISTER UPLIFT SCOPES
+Uplift Scope [main] 4: zp[1]:18 [ main::$2 ] 4: zp[1]:19 [ main::$3 ] 4: zp[1]:20 [ main::$4 ] 4: zp[1]:21 [ main::$5 ] 4: zp[1]:22 [ main::$6 ] 4: zp[1]:23 [ main::$7 ] 4: zp[1]:24 [ main::$8 ] 0.44: zp[1]:2 [ main::bu ] 0.4: zp[1]:3 [ main::bs ] 0.36: zp[2]:4 [ main::wu ] 0.33: zp[2]:6 [ main::ws ] 0.31: zp[4]:8 [ main::du ] 0.29: zp[4]:12 [ main::ds ] 0.27: zp[2]:16 [ main::ptr ] 
+Uplift Scope [] 
+
+Uplifting [main] best 168 combination reg byte a [ main::$2 ] reg byte a [ main::$3 ] reg byte a [ main::$4 ] reg byte a [ main::$5 ] zp[1]:22 [ main::$6 ] zp[1]:23 [ main::$7 ] zp[1]:24 [ main::$8 ] zp[1]:2 [ main::bu ] zp[1]:3 [ main::bs ] zp[2]:4 [ main::wu ] zp[2]:6 [ main::ws ] zp[4]:8 [ main::du ] zp[4]:12 [ main::ds ] zp[2]:16 [ main::ptr ] 
+Limited combination testing to 100 combinations of 16384 possible.
+Uplifting [] best 168 combination 
+Attempting to uplift remaining variables inzp[1]:22 [ main::$6 ]
+Uplifting [main] best 162 combination reg byte a [ main::$6 ] 
+Attempting to uplift remaining variables inzp[1]:23 [ main::$7 ]
+Uplifting [main] best 156 combination reg byte a [ main::$7 ] 
+Attempting to uplift remaining variables inzp[1]:24 [ main::$8 ]
+Uplifting [main] best 150 combination reg byte a [ main::$8 ] 
+Attempting to uplift remaining variables inzp[1]:2 [ main::bu ]
+Uplifting [main] best 150 combination zp[1]:2 [ main::bu ] 
+Attempting to uplift remaining variables inzp[1]:3 [ main::bs ]
+Uplifting [main] best 150 combination zp[1]:3 [ main::bs ] 
+
+ASSEMBLER BEFORE OPTIMIZATION
+  // File Comments
+// Test operator BYTE0()
+  // Upstart
+  // Commodore 64 PRG executable file
+.file [name="operator-byte0.prg", type="prg", segments="Program"]
+.segmentdef Program [segments="Basic, Code, Data"]
+.segmentdef Basic [start=$0801]
+.segmentdef Code [start=$80d]
+.segmentdef Data [startAfter="Code"]
+.segment Basic
+:BasicUpstart(main)
+  // Global Constants & labels
+.segment Code
+  // main
+main: {
+    .label SCREEN = $400
+    .label bu = 2
+    .label bs = 3
+    .label wu = 4
+    .label ws = 6
+    .label du = 8
+    .label ds = $c
+    .label ptr = $10
+    // [0] main::bu = 7 -- vbuz1=vbuc1 
+    lda #7
+    sta.z bu
+    // [1] main::bs = 7 -- vbsz1=vbsc1 
+    lda #7
+    sta.z bs
+    // [2] main::wu = $4e20 -- vwuz1=vwuc1 
+    lda #<$4e20
+    sta.z wu
+    lda #>$4e20
+    sta.z wu+1
+    // [3] main::ws = -$b1 -- vwsz1=vwsc1 
+    lda #<-$b1
+    sta.z ws
+    lda #>-$b1
+    sta.z ws+1
+    // [4] main::du = $1e8480 -- vduz1=vduc1 
+    lda #<$1e8480
+    sta.z du
+    lda #>$1e8480
+    sta.z du+1
+    lda #<$1e8480>>$10
+    sta.z du+2
+    lda #>$1e8480>>$10
+    sta.z du+3
+    // [5] main::ds = -$39a4f1 -- vdsz1=vdsc1 
+    lda #<-$39a4f1
+    sta.z ds
+    lda #>-$39a4f1
+    sta.z ds+1
+    lda #<-$39a4f1>>$10
+    sta.z ds+2
+    lda #>-$39a4f1>>$10
+    sta.z ds+3
+    // [6] main::ptr = (byte*) 0 -- pbuz1=pbuc1 
+    lda #<0
+    sta.z ptr
+    lda #>0
+    sta.z ptr+1
+    // [7] *main::SCREEN = <$11 -- _deref_pbuc1=vbuc2 
+    lda #<($11)
+    sta SCREEN
+    // [8] *(main::SCREEN+1) = <$179 -- _deref_pbuc1=vbuc2 
+    lda #<($179)
+    sta SCREEN+1
+    // [9] main::$2 = < main::bu -- vbuaa=_byte0_vbuz1 
+    lda.z bu
+    // [10] *(main::SCREEN+2) = main::$2 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+2
+    // [11] main::$3 = < main::bs -- vbuaa=_byte0_vbsz1 
+    lda.z bs
+    // [12] *(main::SCREEN+3) = main::$3 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+3
+    // [13] main::$4 = < main::wu -- vbuaa=_byte0_vwuz1 
+    lda.z wu
+    // [14] *(main::SCREEN+4) = main::$4 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+4
+    // [15] main::$5 = < main::ws -- vbuaa=_byte0_vwsz1 
+    lda.z ws
+    // [16] *(main::SCREEN+5) = main::$5 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+5
+    // [17] main::$6 = < main::du -- vbuaa=_byte0_vduz1 
+    lda.z du
+    // [18] *(main::SCREEN+6) = main::$6 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+6
+    // [19] main::$7 = < main::ds -- vbuaa=_byte0_vdsz1 
+    lda.z ds
+    // [20] *(main::SCREEN+7) = main::$7 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+7
+    // [21] main::$8 = < main::ptr -- vbuaa=_byte0_pbuz1 
+    lda.z ptr
+    // [22] *(main::SCREEN+8) = main::$8 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+8
+    jmp __breturn
+    // main::@return
+  __breturn:
+    // [23] return 
+    rts
+}
+  // File Data
+
+ASSEMBLER OPTIMIZATIONS
+Removing instruction jmp __breturn
+Succesful ASM optimization Pass5NextJumpElimination
+Removing instruction lda #7
+Removing instruction lda #>0
+Succesful ASM optimization Pass5UnnecesaryLoadElimination
+Removing instruction __breturn:
+Succesful ASM optimization Pass5UnusedLabelElimination
+
+FINAL SYMBOL TABLE
+void main()
+byte~ main::$2 reg byte a 4.0
+byte~ main::$3 reg byte a 4.0
+byte~ main::$4 reg byte a 4.0
+byte~ main::$5 reg byte a 4.0
+byte~ main::$6 reg byte a 4.0
+byte~ main::$7 reg byte a 4.0
+byte~ main::$8 reg byte a 4.0
+const nomodify byte* main::SCREEN = (byte*) 1024
+volatile signed byte main::bs loadstore zp[1]:3 0.4
+volatile byte main::bu loadstore zp[1]:2 0.4444444444444444
+volatile signed dword main::ds loadstore zp[4]:12 0.2857142857142857
+volatile dword main::du loadstore zp[4]:8 0.3076923076923077
+byte main::i
+volatile byte* main::ptr loadstore zp[2]:16 0.26666666666666666
+volatile signed word main::ws loadstore zp[2]:6 0.3333333333333333
+volatile word main::wu loadstore zp[2]:4 0.36363636363636365
+
+zp[1]:2 [ main::bu ]
+zp[1]:3 [ main::bs ]
+zp[2]:4 [ main::wu ]
+zp[2]:6 [ main::ws ]
+zp[4]:8 [ main::du ]
+zp[4]:12 [ main::ds ]
+zp[2]:16 [ main::ptr ]
+reg byte a [ main::$2 ]
+reg byte a [ main::$3 ]
+reg byte a [ main::$4 ]
+reg byte a [ main::$5 ]
+reg byte a [ main::$6 ]
+reg byte a [ main::$7 ]
+reg byte a [ main::$8 ]
+
+
+FINAL ASSEMBLER
+Score: 143
+
+  // File Comments
+// Test operator BYTE0()
+  // Upstart
+  // Commodore 64 PRG executable file
+.file [name="operator-byte0.prg", type="prg", segments="Program"]
+.segmentdef Program [segments="Basic, Code, Data"]
+.segmentdef Basic [start=$0801]
+.segmentdef Code [start=$80d]
+.segmentdef Data [startAfter="Code"]
+.segment Basic
+:BasicUpstart(main)
+  // Global Constants & labels
+.segment Code
+  // main
+main: {
+    .label SCREEN = $400
+    .label bu = 2
+    .label bs = 3
+    .label wu = 4
+    .label ws = 6
+    .label du = 8
+    .label ds = $c
+    .label ptr = $10
+    // bu = 7
+    // [0] main::bu = 7 -- vbuz1=vbuc1 
+    lda #7
+    sta.z bu
+    // bs = 7
+    // [1] main::bs = 7 -- vbsz1=vbsc1 
+    sta.z bs
+    // wu = 20000
+    // [2] main::wu = $4e20 -- vwuz1=vwuc1 
+    lda #<$4e20
+    sta.z wu
+    lda #>$4e20
+    sta.z wu+1
+    // ws = -177
+    // [3] main::ws = -$b1 -- vwsz1=vwsc1 
+    lda #<-$b1
+    sta.z ws
+    lda #>-$b1
+    sta.z ws+1
+    // du = 2000000
+    // [4] main::du = $1e8480 -- vduz1=vduc1 
+    lda #<$1e8480
+    sta.z du
+    lda #>$1e8480
+    sta.z du+1
+    lda #<$1e8480>>$10
+    sta.z du+2
+    lda #>$1e8480>>$10
+    sta.z du+3
+    // ds = -3777777
+    // [5] main::ds = -$39a4f1 -- vdsz1=vdsc1 
+    lda #<-$39a4f1
+    sta.z ds
+    lda #>-$39a4f1
+    sta.z ds+1
+    lda #<-$39a4f1>>$10
+    sta.z ds+2
+    lda #>-$39a4f1>>$10
+    sta.z ds+3
+    // ptr = 0x0000
+    // [6] main::ptr = (byte*) 0 -- pbuz1=pbuc1 
+    lda #<0
+    sta.z ptr
+    sta.z ptr+1
+    // SCREEN[i++] = BYTE0(17)
+    // [7] *main::SCREEN = <$11 -- _deref_pbuc1=vbuc2 
+    lda #<($11)
+    sta SCREEN
+    // SCREEN[i++] = BYTE0(377)
+    // [8] *(main::SCREEN+1) = <$179 -- _deref_pbuc1=vbuc2 
+    lda #<($179)
+    sta SCREEN+1
+    // BYTE0(bu)
+    // [9] main::$2 = < main::bu -- vbuaa=_byte0_vbuz1 
+    lda.z bu
+    // SCREEN[i++] = BYTE0(bu)
+    // [10] *(main::SCREEN+2) = main::$2 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+2
+    // BYTE0(bs)
+    // [11] main::$3 = < main::bs -- vbuaa=_byte0_vbsz1 
+    lda.z bs
+    // SCREEN[i++] = BYTE0(bs)
+    // [12] *(main::SCREEN+3) = main::$3 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+3
+    // BYTE0(wu)
+    // [13] main::$4 = < main::wu -- vbuaa=_byte0_vwuz1 
+    lda.z wu
+    // SCREEN[i++] = BYTE0(wu)
+    // [14] *(main::SCREEN+4) = main::$4 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+4
+    // BYTE0(ws)
+    // [15] main::$5 = < main::ws -- vbuaa=_byte0_vwsz1 
+    lda.z ws
+    // SCREEN[i++] = BYTE0(ws)
+    // [16] *(main::SCREEN+5) = main::$5 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+5
+    // BYTE0(du)
+    // [17] main::$6 = < main::du -- vbuaa=_byte0_vduz1 
+    lda.z du
+    // SCREEN[i++] = BYTE0(du)
+    // [18] *(main::SCREEN+6) = main::$6 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+6
+    // BYTE0(ds)
+    // [19] main::$7 = < main::ds -- vbuaa=_byte0_vdsz1 
+    lda.z ds
+    // SCREEN[i++] = BYTE0(ds)
+    // [20] *(main::SCREEN+7) = main::$7 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+7
+    // BYTE0(ptr)
+    // [21] main::$8 = < main::ptr -- vbuaa=_byte0_pbuz1 
+    lda.z ptr
+    // SCREEN[i++] = BYTE0(ptr)
+    // [22] *(main::SCREEN+8) = main::$8 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+8
+    // main::@return
+    // }
+    // [23] return 
+    rts
+}
+  // File Data
+
diff --git a/src/test/ref/operator-byte0.sym b/src/test/ref/operator-byte0.sym
new file mode 100644
index 000000000..fc72fec9a
--- /dev/null
+++ b/src/test/ref/operator-byte0.sym
@@ -0,0 +1,32 @@
+void main()
+byte~ main::$2 reg byte a 4.0
+byte~ main::$3 reg byte a 4.0
+byte~ main::$4 reg byte a 4.0
+byte~ main::$5 reg byte a 4.0
+byte~ main::$6 reg byte a 4.0
+byte~ main::$7 reg byte a 4.0
+byte~ main::$8 reg byte a 4.0
+const nomodify byte* main::SCREEN = (byte*) 1024
+volatile signed byte main::bs loadstore zp[1]:3 0.4
+volatile byte main::bu loadstore zp[1]:2 0.4444444444444444
+volatile signed dword main::ds loadstore zp[4]:12 0.2857142857142857
+volatile dword main::du loadstore zp[4]:8 0.3076923076923077
+byte main::i
+volatile byte* main::ptr loadstore zp[2]:16 0.26666666666666666
+volatile signed word main::ws loadstore zp[2]:6 0.3333333333333333
+volatile word main::wu loadstore zp[2]:4 0.36363636363636365
+
+zp[1]:2 [ main::bu ]
+zp[1]:3 [ main::bs ]
+zp[2]:4 [ main::wu ]
+zp[2]:6 [ main::ws ]
+zp[4]:8 [ main::du ]
+zp[4]:12 [ main::ds ]
+zp[2]:16 [ main::ptr ]
+reg byte a [ main::$2 ]
+reg byte a [ main::$3 ]
+reg byte a [ main::$4 ]
+reg byte a [ main::$5 ]
+reg byte a [ main::$6 ]
+reg byte a [ main::$7 ]
+reg byte a [ main::$8 ]
diff --git a/src/test/ref/operator-byte1.asm b/src/test/ref/operator-byte1.asm
new file mode 100644
index 000000000..d93622ce8
--- /dev/null
+++ b/src/test/ref/operator-byte1.asm
@@ -0,0 +1,91 @@
+// Test operator BYTE0()
+  // Commodore 64 PRG executable file
+.file [name="operator-byte1.prg", type="prg", segments="Program"]
+.segmentdef Program [segments="Basic, Code, Data"]
+.segmentdef Basic [start=$0801]
+.segmentdef Code [start=$80d]
+.segmentdef Data [startAfter="Code"]
+.segment Basic
+:BasicUpstart(main)
+.segment Code
+main: {
+    .label SCREEN = $400
+    .label bu = 2
+    .label bs = 3
+    .label wu = 4
+    .label ws = 6
+    .label du = 8
+    .label ds = $c
+    .label ptr = $10
+    // bu = 7
+    lda #7
+    sta.z bu
+    // bs = 7
+    sta.z bs
+    // wu = 20000
+    lda #<$4e20
+    sta.z wu
+    lda #>$4e20
+    sta.z wu+1
+    // ws = -177
+    lda #<-$b1
+    sta.z ws
+    lda #>-$b1
+    sta.z ws+1
+    // du = 2000000
+    lda #<$1e8480
+    sta.z du
+    lda #>$1e8480
+    sta.z du+1
+    lda #<$1e8480>>$10
+    sta.z du+2
+    lda #>$1e8480>>$10
+    sta.z du+3
+    // ds = -3777777
+    lda #<-$39a4f1
+    sta.z ds
+    lda #>-$39a4f1
+    sta.z ds+1
+    lda #<-$39a4f1>>$10
+    sta.z ds+2
+    lda #>-$39a4f1>>$10
+    sta.z ds+3
+    // ptr = 0x0000
+    lda #<0
+    sta.z ptr
+    sta.z ptr+1
+    // SCREEN[i++] = BYTE1(17)
+    sta SCREEN
+    // SCREEN[i++] = BYTE1(377)
+    lda #>($179)
+    sta SCREEN+1
+    // BYTE1(bu)
+    lda #0
+    // SCREEN[i++] = BYTE1(bu)
+    sta SCREEN+2
+    // BYTE1(bs)
+    // SCREEN[i++] = BYTE1(bs)
+    sta SCREEN+3
+    // BYTE1(wu)
+    lda.z wu+1
+    // SCREEN[i++] = BYTE1(wu)
+    sta SCREEN+4
+    // BYTE1(ws)
+    lda.z ws+1
+    // SCREEN[i++] = BYTE1(ws)
+    sta SCREEN+5
+    // BYTE1(du)
+    lda.z du+1
+    // SCREEN[i++] = BYTE1(du)
+    sta SCREEN+6
+    // BYTE1(ds)
+    lda.z ds+1
+    // SCREEN[i++] = BYTE1(ds)
+    sta SCREEN+7
+    // BYTE1(ptr)
+    lda.z ptr+1
+    // SCREEN[i++] = BYTE1(ptr)
+    sta SCREEN+8
+    // }
+    rts
+}
diff --git a/src/test/ref/operator-byte1.cfg b/src/test/ref/operator-byte1.cfg
new file mode 100644
index 000000000..d4a9520cc
--- /dev/null
+++ b/src/test/ref/operator-byte1.cfg
@@ -0,0 +1,30 @@
+
+void main()
+main: scope:[main]  from
+  [0] main::bu = 7
+  [1] main::bs = 7
+  [2] main::wu = $4e20
+  [3] main::ws = -$b1
+  [4] main::du = $1e8480
+  [5] main::ds = -$39a4f1
+  [6] main::ptr = (byte*) 0
+  [7] *main::SCREEN = 0
+  [8] *(main::SCREEN+1) = >$179
+  [9] main::$2 = > main::bu
+  [10] *(main::SCREEN+2) = main::$2
+  [11] main::$3 = > main::bs
+  [12] *(main::SCREEN+3) = main::$3
+  [13] main::$4 = > main::wu
+  [14] *(main::SCREEN+4) = main::$4
+  [15] main::$5 = > main::ws
+  [16] *(main::SCREEN+5) = main::$5
+  [17] main::$6 = > main::du
+  [18] *(main::SCREEN+6) = main::$6
+  [19] main::$7 = > main::ds
+  [20] *(main::SCREEN+7) = main::$7
+  [21] main::$8 = > main::ptr
+  [22] *(main::SCREEN+8) = main::$8
+  to:main::@return
+main::@return: scope:[main]  from main
+  [23] return 
+  to:@return
diff --git a/src/test/ref/operator-byte1.log b/src/test/ref/operator-byte1.log
new file mode 100644
index 000000000..1bcf25553
--- /dev/null
+++ b/src/test/ref/operator-byte1.log
@@ -0,0 +1,608 @@
+
+CONTROL FLOW GRAPH SSA
+
+void main()
+main: scope:[main]  from __start
+  main::bu = 7
+  main::bs = 7
+  main::wu = $4e20
+  main::ws = -$b1
+  main::du = $1e8480
+  main::ds = -$39a4f1
+  main::ptr = (byte*)0
+  main::i#0 = 0
+  main::$0 = > $11
+  main::SCREEN[main::i#0] = main::$0
+  main::i#1 = ++ main::i#0
+  main::$1 = > $179
+  main::SCREEN[main::i#1] = main::$1
+  main::i#2 = ++ main::i#1
+  main::$2 = > main::bu
+  main::SCREEN[main::i#2] = main::$2
+  main::i#3 = ++ main::i#2
+  main::$3 = > main::bs
+  main::SCREEN[main::i#3] = main::$3
+  main::i#4 = ++ main::i#3
+  main::$4 = > main::wu
+  main::SCREEN[main::i#4] = main::$4
+  main::i#5 = ++ main::i#4
+  main::$5 = > main::ws
+  main::SCREEN[main::i#5] = main::$5
+  main::i#6 = ++ main::i#5
+  main::$6 = > main::du
+  main::SCREEN[main::i#6] = main::$6
+  main::i#7 = ++ main::i#6
+  main::$7 = > main::ds
+  main::SCREEN[main::i#7] = main::$7
+  main::i#8 = ++ main::i#7
+  main::$8 = > main::ptr
+  main::SCREEN[main::i#8] = main::$8
+  main::i#9 = ++ main::i#8
+  to:main::@return
+main::@return: scope:[main]  from main
+  return 
+  to:@return
+
+void __start()
+__start: scope:[__start]  from
+  call main 
+  to:__start::@1
+__start::@1: scope:[__start]  from __start
+  to:__start::@return
+__start::@return: scope:[__start]  from __start::@1
+  return 
+  to:@return
+
+SYMBOL TABLE SSA
+void __start()
+void main()
+byte~ main::$0
+byte~ main::$1
+byte~ main::$2
+byte~ main::$3
+byte~ main::$4
+byte~ main::$5
+byte~ main::$6
+byte~ main::$7
+byte~ main::$8
+const nomodify byte* main::SCREEN = (byte*)$400
+volatile signed byte main::bs loadstore
+volatile byte main::bu loadstore
+volatile signed dword main::ds loadstore
+volatile dword main::du loadstore
+byte main::i
+byte main::i#0
+byte main::i#1
+byte main::i#2
+byte main::i#3
+byte main::i#4
+byte main::i#5
+byte main::i#6
+byte main::i#7
+byte main::i#8
+byte main::i#9
+volatile byte* main::ptr loadstore
+volatile signed word main::ws loadstore
+volatile word main::wu loadstore
+
+Simplifying constant pointer cast (byte*) 1024
+Simplifying constant pointer cast (byte*) 0
+Successful SSA optimization PassNCastSimplification
+Constant right-side identified [8] main::$0 = > $11
+Constant right-side identified [11] main::$1 = > $179
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#0 = 0
+Constant main::$0 = >$11
+Constant main::$1 = >$179
+Successful SSA optimization Pass2ConstantIdentification
+Simplifying constant evaluating to zero >$11 in 
+Successful SSA optimization PassNSimplifyConstantZero
+Simplifying expression containing zero main::SCREEN in [9] main::SCREEN[main::i#0] = main::$0
+Successful SSA optimization PassNSimplifyExpressionWithZero
+Eliminating unused variable main::i#9 and assignment [31] main::i#9 = ++ main::i#8
+Successful SSA optimization PassNEliminateUnusedVars
+Removing unused procedure __start
+Removing unused procedure block __start
+Removing unused procedure block __start::@1
+Removing unused procedure block __start::@return
+Successful SSA optimization PassNEliminateEmptyStart
+Constant right-side identified [8] main::i#1 = ++ main::i#0
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#1 = ++main::i#0
+Successful SSA optimization Pass2ConstantIdentification
+Constant right-side identified [9] main::i#2 = ++ main::i#1
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#2 = ++main::i#1
+Successful SSA optimization Pass2ConstantIdentification
+Constant right-side identified [11] main::i#3 = ++ main::i#2
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#3 = ++main::i#2
+Successful SSA optimization Pass2ConstantIdentification
+Constant right-side identified [13] main::i#4 = ++ main::i#3
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#4 = ++main::i#3
+Successful SSA optimization Pass2ConstantIdentification
+Constant right-side identified [15] main::i#5 = ++ main::i#4
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#5 = ++main::i#4
+Successful SSA optimization Pass2ConstantIdentification
+Constant right-side identified [17] main::i#6 = ++ main::i#5
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#6 = ++main::i#5
+Successful SSA optimization Pass2ConstantIdentification
+Constant right-side identified [19] main::i#7 = ++ main::i#6
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#7 = ++main::i#6
+Successful SSA optimization Pass2ConstantIdentification
+Constant right-side identified [21] main::i#8 = ++ main::i#7
+Successful SSA optimization Pass2ConstantRValueConsolidation
+Constant main::i#8 = ++main::i#7
+Successful SSA optimization Pass2ConstantIdentification
+Inlining constant with different constant siblings main::i#0
+Inlining constant with different constant siblings main::i#1
+Inlining constant with different constant siblings main::i#2
+Inlining constant with different constant siblings main::i#3
+Inlining constant with different constant siblings main::i#4
+Inlining constant with different constant siblings main::i#5
+Inlining constant with different constant siblings main::i#6
+Inlining constant with different constant siblings main::i#7
+Inlining constant with different constant siblings main::i#8
+Constant inlined main::i#8 = ++++++++++++++++0
+Constant inlined main::i#7 = ++++++++++++++0
+Constant inlined main::$1 = >$179
+Constant inlined main::i#4 = ++++++++0
+Constant inlined main::i#3 = ++++++0
+Constant inlined main::i#6 = ++++++++++++0
+Constant inlined main::$0 = 0
+Constant inlined main::i#5 = ++++++++++0
+Constant inlined main::i#0 = 0
+Constant inlined main::i#2 = ++++0
+Constant inlined main::i#1 = ++0
+Successful SSA optimization Pass2ConstantInlining
+Consolidated array index constant in *(main::SCREEN+++0)
+Consolidated array index constant in *(main::SCREEN+++++0)
+Consolidated array index constant in *(main::SCREEN+++++++0)
+Consolidated array index constant in *(main::SCREEN+++++++++0)
+Consolidated array index constant in *(main::SCREEN+++++++++++0)
+Consolidated array index constant in *(main::SCREEN+++++++++++++0)
+Consolidated array index constant in *(main::SCREEN+++++++++++++++0)
+Consolidated array index constant in *(main::SCREEN+++++++++++++++++0)
+Successful SSA optimization Pass2ConstantAdditionElimination
+Simplifying constant integer increment ++0
+Simplifying constant integer increment ++0
+Simplifying constant integer increment ++1
+Simplifying constant integer increment ++2
+Simplifying constant integer increment ++3
+Simplifying constant integer increment ++4
+Simplifying constant integer increment ++5
+Simplifying constant integer increment ++6
+Successful SSA optimization Pass2ConstantSimplification
+Simplifying constant integer increment ++1
+Simplifying constant integer increment ++2
+Simplifying constant integer increment ++3
+Simplifying constant integer increment ++4
+Simplifying constant integer increment ++5
+Simplifying constant integer increment ++6
+Simplifying constant integer increment ++7
+Successful SSA optimization Pass2ConstantSimplification
+Finalized unsigned number type (word) $179
+Successful SSA optimization PassNFinalizeNumberTypeConversions
+CALL GRAPH
+
+Created 0 initial phi equivalence classes
+Coalesced down to 0 phi equivalence classes
+
+FINAL CONTROL FLOW GRAPH
+
+void main()
+main: scope:[main]  from
+  [0] main::bu = 7
+  [1] main::bs = 7
+  [2] main::wu = $4e20
+  [3] main::ws = -$b1
+  [4] main::du = $1e8480
+  [5] main::ds = -$39a4f1
+  [6] main::ptr = (byte*) 0
+  [7] *main::SCREEN = 0
+  [8] *(main::SCREEN+1) = >$179
+  [9] main::$2 = > main::bu
+  [10] *(main::SCREEN+2) = main::$2
+  [11] main::$3 = > main::bs
+  [12] *(main::SCREEN+3) = main::$3
+  [13] main::$4 = > main::wu
+  [14] *(main::SCREEN+4) = main::$4
+  [15] main::$5 = > main::ws
+  [16] *(main::SCREEN+5) = main::$5
+  [17] main::$6 = > main::du
+  [18] *(main::SCREEN+6) = main::$6
+  [19] main::$7 = > main::ds
+  [20] *(main::SCREEN+7) = main::$7
+  [21] main::$8 = > main::ptr
+  [22] *(main::SCREEN+8) = main::$8
+  to:main::@return
+main::@return: scope:[main]  from main
+  [23] return 
+  to:@return
+
+
+VARIABLE REGISTER WEIGHTS
+void main()
+byte~ main::$2 4.0
+byte~ main::$3 4.0
+byte~ main::$4 4.0
+byte~ main::$5 4.0
+byte~ main::$6 4.0
+byte~ main::$7 4.0
+byte~ main::$8 4.0
+volatile signed byte main::bs loadstore 0.4
+volatile byte main::bu loadstore 0.4444444444444444
+volatile signed dword main::ds loadstore 0.2857142857142857
+volatile dword main::du loadstore 0.3076923076923077
+byte main::i
+volatile byte* main::ptr loadstore 0.26666666666666666
+volatile signed word main::ws loadstore 0.3333333333333333
+volatile word main::wu loadstore 0.36363636363636365
+
+Initial phi equivalence classes
+Added variable main::bu to live range equivalence class [ main::bu ]
+Added variable main::bs to live range equivalence class [ main::bs ]
+Added variable main::wu to live range equivalence class [ main::wu ]
+Added variable main::ws to live range equivalence class [ main::ws ]
+Added variable main::du to live range equivalence class [ main::du ]
+Added variable main::ds to live range equivalence class [ main::ds ]
+Added variable main::ptr to live range equivalence class [ main::ptr ]
+Added variable main::$2 to live range equivalence class [ main::$2 ]
+Added variable main::$3 to live range equivalence class [ main::$3 ]
+Added variable main::$4 to live range equivalence class [ main::$4 ]
+Added variable main::$5 to live range equivalence class [ main::$5 ]
+Added variable main::$6 to live range equivalence class [ main::$6 ]
+Added variable main::$7 to live range equivalence class [ main::$7 ]
+Added variable main::$8 to live range equivalence class [ main::$8 ]
+Complete equivalence classes
+[ main::bu ]
+[ main::bs ]
+[ main::wu ]
+[ main::ws ]
+[ main::du ]
+[ main::ds ]
+[ main::ptr ]
+[ main::$2 ]
+[ main::$3 ]
+[ main::$4 ]
+[ main::$5 ]
+[ main::$6 ]
+[ main::$7 ]
+[ main::$8 ]
+Allocated zp[1]:2 [ main::bu ]
+Allocated zp[1]:3 [ main::bs ]
+Allocated zp[2]:4 [ main::wu ]
+Allocated zp[2]:6 [ main::ws ]
+Allocated zp[4]:8 [ main::du ]
+Allocated zp[4]:12 [ main::ds ]
+Allocated zp[2]:16 [ main::ptr ]
+Allocated zp[1]:18 [ main::$2 ]
+Allocated zp[1]:19 [ main::$3 ]
+Allocated zp[1]:20 [ main::$4 ]
+Allocated zp[1]:21 [ main::$5 ]
+Allocated zp[1]:22 [ main::$6 ]
+Allocated zp[1]:23 [ main::$7 ]
+Allocated zp[1]:24 [ main::$8 ]
+REGISTER UPLIFT POTENTIAL REGISTERS
+Statement [0] main::bu = 7 [ main::bu ] (  [ main::bu ] { }  ) always clobbers reg byte a 
+Statement [1] main::bs = 7 [ main::bu main::bs ] (  [ main::bu main::bs ] { }  ) always clobbers reg byte a 
+Statement [2] main::wu = $4e20 [ main::bu main::bs main::wu ] (  [ main::bu main::bs main::wu ] { }  ) always clobbers reg byte a 
+Statement [3] main::ws = -$b1 [ main::bu main::bs main::wu main::ws ] (  [ main::bu main::bs main::wu main::ws ] { }  ) always clobbers reg byte a 
+Statement [4] main::du = $1e8480 [ main::bu main::bs main::wu main::ws main::du ] (  [ main::bu main::bs main::wu main::ws main::du ] { }  ) always clobbers reg byte a 
+Statement [5] main::ds = -$39a4f1 [ main::bu main::bs main::wu main::ws main::du main::ds ] (  [ main::bu main::bs main::wu main::ws main::du main::ds ] { }  ) always clobbers reg byte a 
+Statement [6] main::ptr = (byte*) 0 [ main::bu main::bs main::wu main::ws main::du main::ds main::ptr ] (  [ main::bu main::bs main::wu main::ws main::du main::ds main::ptr ] { }  ) always clobbers reg byte a 
+Statement [7] *main::SCREEN = 0 [ main::bu main::bs main::wu main::ws main::du main::ds main::ptr ] (  [ main::bu main::bs main::wu main::ws main::du main::ds main::ptr ] { }  ) always clobbers reg byte a 
+Statement [8] *(main::SCREEN+1) = >$179 [ main::bu main::bs main::wu main::ws main::du main::ds main::ptr ] (  [ main::bu main::bs main::wu main::ws main::du main::ds main::ptr ] { }  ) always clobbers reg byte a 
+Potential registers zp[1]:2 [ main::bu ] : zp[1]:2 , 
+Potential registers zp[1]:3 [ main::bs ] : zp[1]:3 , 
+Potential registers zp[2]:4 [ main::wu ] : zp[2]:4 , 
+Potential registers zp[2]:6 [ main::ws ] : zp[2]:6 , 
+Potential registers zp[4]:8 [ main::du ] : zp[4]:8 , 
+Potential registers zp[4]:12 [ main::ds ] : zp[4]:12 , 
+Potential registers zp[2]:16 [ main::ptr ] : zp[2]:16 , 
+Potential registers zp[1]:18 [ main::$2 ] : zp[1]:18 , reg byte a , reg byte x , reg byte y , 
+Potential registers zp[1]:19 [ main::$3 ] : zp[1]:19 , reg byte a , reg byte x , reg byte y , 
+Potential registers zp[1]:20 [ main::$4 ] : zp[1]:20 , reg byte a , reg byte x , reg byte y , 
+Potential registers zp[1]:21 [ main::$5 ] : zp[1]:21 , reg byte a , reg byte x , reg byte y , 
+Potential registers zp[1]:22 [ main::$6 ] : zp[1]:22 , reg byte a , reg byte x , reg byte y , 
+Potential registers zp[1]:23 [ main::$7 ] : zp[1]:23 , reg byte a , reg byte x , reg byte y , 
+Potential registers zp[1]:24 [ main::$8 ] : zp[1]:24 , reg byte a , reg byte x , reg byte y , 
+
+REGISTER UPLIFT SCOPES
+Uplift Scope [main] 4: zp[1]:18 [ main::$2 ] 4: zp[1]:19 [ main::$3 ] 4: zp[1]:20 [ main::$4 ] 4: zp[1]:21 [ main::$5 ] 4: zp[1]:22 [ main::$6 ] 4: zp[1]:23 [ main::$7 ] 4: zp[1]:24 [ main::$8 ] 0.44: zp[1]:2 [ main::bu ] 0.4: zp[1]:3 [ main::bs ] 0.36: zp[2]:4 [ main::wu ] 0.33: zp[2]:6 [ main::ws ] 0.31: zp[4]:8 [ main::du ] 0.29: zp[4]:12 [ main::ds ] 0.27: zp[2]:16 [ main::ptr ] 
+Uplift Scope [] 
+
+Uplifting [main] best 166 combination reg byte a [ main::$2 ] reg byte a [ main::$3 ] reg byte a [ main::$4 ] reg byte a [ main::$5 ] zp[1]:22 [ main::$6 ] zp[1]:23 [ main::$7 ] zp[1]:24 [ main::$8 ] zp[1]:2 [ main::bu ] zp[1]:3 [ main::bs ] zp[2]:4 [ main::wu ] zp[2]:6 [ main::ws ] zp[4]:8 [ main::du ] zp[4]:12 [ main::ds ] zp[2]:16 [ main::ptr ] 
+Limited combination testing to 100 combinations of 16384 possible.
+Uplifting [] best 166 combination 
+Attempting to uplift remaining variables inzp[1]:22 [ main::$6 ]
+Uplifting [main] best 160 combination reg byte a [ main::$6 ] 
+Attempting to uplift remaining variables inzp[1]:23 [ main::$7 ]
+Uplifting [main] best 154 combination reg byte a [ main::$7 ] 
+Attempting to uplift remaining variables inzp[1]:24 [ main::$8 ]
+Uplifting [main] best 148 combination reg byte a [ main::$8 ] 
+Attempting to uplift remaining variables inzp[1]:2 [ main::bu ]
+Uplifting [main] best 148 combination zp[1]:2 [ main::bu ] 
+Attempting to uplift remaining variables inzp[1]:3 [ main::bs ]
+Uplifting [main] best 148 combination zp[1]:3 [ main::bs ] 
+
+ASSEMBLER BEFORE OPTIMIZATION
+  // File Comments
+// Test operator BYTE0()
+  // Upstart
+  // Commodore 64 PRG executable file
+.file [name="operator-byte1.prg", type="prg", segments="Program"]
+.segmentdef Program [segments="Basic, Code, Data"]
+.segmentdef Basic [start=$0801]
+.segmentdef Code [start=$80d]
+.segmentdef Data [startAfter="Code"]
+.segment Basic
+:BasicUpstart(main)
+  // Global Constants & labels
+.segment Code
+  // main
+main: {
+    .label SCREEN = $400
+    .label bu = 2
+    .label bs = 3
+    .label wu = 4
+    .label ws = 6
+    .label du = 8
+    .label ds = $c
+    .label ptr = $10
+    // [0] main::bu = 7 -- vbuz1=vbuc1 
+    lda #7
+    sta.z bu
+    // [1] main::bs = 7 -- vbsz1=vbsc1 
+    lda #7
+    sta.z bs
+    // [2] main::wu = $4e20 -- vwuz1=vwuc1 
+    lda #<$4e20
+    sta.z wu
+    lda #>$4e20
+    sta.z wu+1
+    // [3] main::ws = -$b1 -- vwsz1=vwsc1 
+    lda #<-$b1
+    sta.z ws
+    lda #>-$b1
+    sta.z ws+1
+    // [4] main::du = $1e8480 -- vduz1=vduc1 
+    lda #<$1e8480
+    sta.z du
+    lda #>$1e8480
+    sta.z du+1
+    lda #<$1e8480>>$10
+    sta.z du+2
+    lda #>$1e8480>>$10
+    sta.z du+3
+    // [5] main::ds = -$39a4f1 -- vdsz1=vdsc1 
+    lda #<-$39a4f1
+    sta.z ds
+    lda #>-$39a4f1
+    sta.z ds+1
+    lda #<-$39a4f1>>$10
+    sta.z ds+2
+    lda #>-$39a4f1>>$10
+    sta.z ds+3
+    // [6] main::ptr = (byte*) 0 -- pbuz1=pbuc1 
+    lda #<0
+    sta.z ptr
+    lda #>0
+    sta.z ptr+1
+    // [7] *main::SCREEN = 0 -- _deref_pbuc1=vbuc2 
+    lda #0
+    sta SCREEN
+    // [8] *(main::SCREEN+1) = >$179 -- _deref_pbuc1=vbuc2 
+    lda #>($179)
+    sta SCREEN+1
+    // [9] main::$2 = > main::bu -- vbuaa=_byte1_vbuz1 
+    lda #0
+    // [10] *(main::SCREEN+2) = main::$2 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+2
+    // [11] main::$3 = > main::bs -- vbuaa=_byte1_vbsz1 
+    lda #0
+    // [12] *(main::SCREEN+3) = main::$3 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+3
+    // [13] main::$4 = > main::wu -- vbuaa=_byte1_vwuz1 
+    lda.z wu+1
+    // [14] *(main::SCREEN+4) = main::$4 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+4
+    // [15] main::$5 = > main::ws -- vbuaa=_byte1_vwsz1 
+    lda.z ws+1
+    // [16] *(main::SCREEN+5) = main::$5 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+5
+    // [17] main::$6 = > main::du -- vbuaa=_byte1_vduz1 
+    lda.z du+1
+    // [18] *(main::SCREEN+6) = main::$6 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+6
+    // [19] main::$7 = > main::ds -- vbuaa=_byte1_vdsz1 
+    lda.z ds+1
+    // [20] *(main::SCREEN+7) = main::$7 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+7
+    // [21] main::$8 = > main::ptr -- vbuaa=_byte1_pbuz1 
+    lda.z ptr+1
+    // [22] *(main::SCREEN+8) = main::$8 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+8
+    jmp __breturn
+    // main::@return
+  __breturn:
+    // [23] return 
+    rts
+}
+  // File Data
+
+ASSEMBLER OPTIMIZATIONS
+Removing instruction jmp __breturn
+Succesful ASM optimization Pass5NextJumpElimination
+Removing instruction lda #7
+Removing instruction lda #>0
+Removing instruction lda #0
+Removing instruction lda #0
+Succesful ASM optimization Pass5UnnecesaryLoadElimination
+Removing instruction __breturn:
+Succesful ASM optimization Pass5UnusedLabelElimination
+
+FINAL SYMBOL TABLE
+void main()
+byte~ main::$2 reg byte a 4.0
+byte~ main::$3 reg byte a 4.0
+byte~ main::$4 reg byte a 4.0
+byte~ main::$5 reg byte a 4.0
+byte~ main::$6 reg byte a 4.0
+byte~ main::$7 reg byte a 4.0
+byte~ main::$8 reg byte a 4.0
+const nomodify byte* main::SCREEN = (byte*) 1024
+volatile signed byte main::bs loadstore zp[1]:3 0.4
+volatile byte main::bu loadstore zp[1]:2 0.4444444444444444
+volatile signed dword main::ds loadstore zp[4]:12 0.2857142857142857
+volatile dword main::du loadstore zp[4]:8 0.3076923076923077
+byte main::i
+volatile byte* main::ptr loadstore zp[2]:16 0.26666666666666666
+volatile signed word main::ws loadstore zp[2]:6 0.3333333333333333
+volatile word main::wu loadstore zp[2]:4 0.36363636363636365
+
+zp[1]:2 [ main::bu ]
+zp[1]:3 [ main::bs ]
+zp[2]:4 [ main::wu ]
+zp[2]:6 [ main::ws ]
+zp[4]:8 [ main::du ]
+zp[4]:12 [ main::ds ]
+zp[2]:16 [ main::ptr ]
+reg byte a [ main::$2 ]
+reg byte a [ main::$3 ]
+reg byte a [ main::$4 ]
+reg byte a [ main::$5 ]
+reg byte a [ main::$6 ]
+reg byte a [ main::$7 ]
+reg byte a [ main::$8 ]
+
+
+FINAL ASSEMBLER
+Score: 137
+
+  // File Comments
+// Test operator BYTE0()
+  // Upstart
+  // Commodore 64 PRG executable file
+.file [name="operator-byte1.prg", type="prg", segments="Program"]
+.segmentdef Program [segments="Basic, Code, Data"]
+.segmentdef Basic [start=$0801]
+.segmentdef Code [start=$80d]
+.segmentdef Data [startAfter="Code"]
+.segment Basic
+:BasicUpstart(main)
+  // Global Constants & labels
+.segment Code
+  // main
+main: {
+    .label SCREEN = $400
+    .label bu = 2
+    .label bs = 3
+    .label wu = 4
+    .label ws = 6
+    .label du = 8
+    .label ds = $c
+    .label ptr = $10
+    // bu = 7
+    // [0] main::bu = 7 -- vbuz1=vbuc1 
+    lda #7
+    sta.z bu
+    // bs = 7
+    // [1] main::bs = 7 -- vbsz1=vbsc1 
+    sta.z bs
+    // wu = 20000
+    // [2] main::wu = $4e20 -- vwuz1=vwuc1 
+    lda #<$4e20
+    sta.z wu
+    lda #>$4e20
+    sta.z wu+1
+    // ws = -177
+    // [3] main::ws = -$b1 -- vwsz1=vwsc1 
+    lda #<-$b1
+    sta.z ws
+    lda #>-$b1
+    sta.z ws+1
+    // du = 2000000
+    // [4] main::du = $1e8480 -- vduz1=vduc1 
+    lda #<$1e8480
+    sta.z du
+    lda #>$1e8480
+    sta.z du+1
+    lda #<$1e8480>>$10
+    sta.z du+2
+    lda #>$1e8480>>$10
+    sta.z du+3
+    // ds = -3777777
+    // [5] main::ds = -$39a4f1 -- vdsz1=vdsc1 
+    lda #<-$39a4f1
+    sta.z ds
+    lda #>-$39a4f1
+    sta.z ds+1
+    lda #<-$39a4f1>>$10
+    sta.z ds+2
+    lda #>-$39a4f1>>$10
+    sta.z ds+3
+    // ptr = 0x0000
+    // [6] main::ptr = (byte*) 0 -- pbuz1=pbuc1 
+    lda #<0
+    sta.z ptr
+    sta.z ptr+1
+    // SCREEN[i++] = BYTE1(17)
+    // [7] *main::SCREEN = 0 -- _deref_pbuc1=vbuc2 
+    sta SCREEN
+    // SCREEN[i++] = BYTE1(377)
+    // [8] *(main::SCREEN+1) = >$179 -- _deref_pbuc1=vbuc2 
+    lda #>($179)
+    sta SCREEN+1
+    // BYTE1(bu)
+    // [9] main::$2 = > main::bu -- vbuaa=_byte1_vbuz1 
+    lda #0
+    // SCREEN[i++] = BYTE1(bu)
+    // [10] *(main::SCREEN+2) = main::$2 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+2
+    // BYTE1(bs)
+    // [11] main::$3 = > main::bs -- vbuaa=_byte1_vbsz1 
+    // SCREEN[i++] = BYTE1(bs)
+    // [12] *(main::SCREEN+3) = main::$3 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+3
+    // BYTE1(wu)
+    // [13] main::$4 = > main::wu -- vbuaa=_byte1_vwuz1 
+    lda.z wu+1
+    // SCREEN[i++] = BYTE1(wu)
+    // [14] *(main::SCREEN+4) = main::$4 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+4
+    // BYTE1(ws)
+    // [15] main::$5 = > main::ws -- vbuaa=_byte1_vwsz1 
+    lda.z ws+1
+    // SCREEN[i++] = BYTE1(ws)
+    // [16] *(main::SCREEN+5) = main::$5 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+5
+    // BYTE1(du)
+    // [17] main::$6 = > main::du -- vbuaa=_byte1_vduz1 
+    lda.z du+1
+    // SCREEN[i++] = BYTE1(du)
+    // [18] *(main::SCREEN+6) = main::$6 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+6
+    // BYTE1(ds)
+    // [19] main::$7 = > main::ds -- vbuaa=_byte1_vdsz1 
+    lda.z ds+1
+    // SCREEN[i++] = BYTE1(ds)
+    // [20] *(main::SCREEN+7) = main::$7 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+7
+    // BYTE1(ptr)
+    // [21] main::$8 = > main::ptr -- vbuaa=_byte1_pbuz1 
+    lda.z ptr+1
+    // SCREEN[i++] = BYTE1(ptr)
+    // [22] *(main::SCREEN+8) = main::$8 -- _deref_pbuc1=vbuaa 
+    sta SCREEN+8
+    // main::@return
+    // }
+    // [23] return 
+    rts
+}
+  // File Data
+
diff --git a/src/test/ref/operator-byte1.sym b/src/test/ref/operator-byte1.sym
new file mode 100644
index 000000000..fc72fec9a
--- /dev/null
+++ b/src/test/ref/operator-byte1.sym
@@ -0,0 +1,32 @@
+void main()
+byte~ main::$2 reg byte a 4.0
+byte~ main::$3 reg byte a 4.0
+byte~ main::$4 reg byte a 4.0
+byte~ main::$5 reg byte a 4.0
+byte~ main::$6 reg byte a 4.0
+byte~ main::$7 reg byte a 4.0
+byte~ main::$8 reg byte a 4.0
+const nomodify byte* main::SCREEN = (byte*) 1024
+volatile signed byte main::bs loadstore zp[1]:3 0.4
+volatile byte main::bu loadstore zp[1]:2 0.4444444444444444
+volatile signed dword main::ds loadstore zp[4]:12 0.2857142857142857
+volatile dword main::du loadstore zp[4]:8 0.3076923076923077
+byte main::i
+volatile byte* main::ptr loadstore zp[2]:16 0.26666666666666666
+volatile signed word main::ws loadstore zp[2]:6 0.3333333333333333
+volatile word main::wu loadstore zp[2]:4 0.36363636363636365
+
+zp[1]:2 [ main::bu ]
+zp[1]:3 [ main::bs ]
+zp[2]:4 [ main::wu ]
+zp[2]:6 [ main::ws ]
+zp[4]:8 [ main::du ]
+zp[4]:12 [ main::ds ]
+zp[2]:16 [ main::ptr ]
+reg byte a [ main::$2 ]
+reg byte a [ main::$3 ]
+reg byte a [ main::$4 ]
+reg byte a [ main::$5 ]
+reg byte a [ main::$6 ]
+reg byte a [ main::$7 ]
+reg byte a [ main::$8 ]