diff --git a/src/test/java/dk/camelot64/kickc/test/TestPrograms.java b/src/test/java/dk/camelot64/kickc/test/TestPrograms.java
index 5699cb209..30a768a41 100644
--- a/src/test/java/dk/camelot64/kickc/test/TestPrograms.java
+++ b/src/test/java/dk/camelot64/kickc/test/TestPrograms.java
@@ -44,6 +44,11 @@ public class TestPrograms {
    public TestPrograms() {
    }
 
+   @Test
+   public void testStrengthReduction1() throws IOException, URISyntaxException {
+      compileAndCompare("strength-reduction-1.c");
+   }
+
    @Test
    public void testProblemBoolCompare2() throws IOException, URISyntaxException {
       compileAndCompare("problem-bool-compare-2.c");
diff --git a/src/test/kc/strength-reduction-1.c b/src/test/kc/strength-reduction-1.c
new file mode 100644
index 000000000..5f0bdd0f8
--- /dev/null
+++ b/src/test/kc/strength-reduction-1.c
@@ -0,0 +1,10 @@
+// Test loop invariant computation detection
+// http://www.cs.toronto.edu/~pekhimenko/courses/cscd70-w18/docs/Lecture%205%20[LICM%20and%20Strength%20Reduction]%2002.08.2018.pdf
+char * SCREEN = 0x0400;
+void main() {
+    char x = *SCREEN;
+    for(char c=0;c<40;c++) {
+        // x+5 is a loop invariant computation
+        SCREEN[c] = x+5;
+    }
+} 
\ No newline at end of file
diff --git a/src/test/ref/strength-reduction-1.asm b/src/test/ref/strength-reduction-1.asm
new file mode 100644
index 000000000..b8058fa39
--- /dev/null
+++ b/src/test/ref/strength-reduction-1.asm
@@ -0,0 +1,28 @@
+// Test loop invariant computation detection
+// http://www.cs.toronto.edu/~pekhimenko/courses/cscd70-w18/docs/Lecture%205%20[LICM%20and%20Strength%20Reduction]%2002.08.2018.pdf
+.pc = $801 "Basic"
+:BasicUpstart(main)
+.pc = $80d "Program"
+  .label SCREEN = $400
+main: {
+    // x = *SCREEN
+    ldx SCREEN
+    ldy #0
+  __b1:
+    // for(char c=0;c<40;c++)
+    cpy #$28
+    bcc __b2
+    // }
+    rts
+  __b2:
+    // x+5
+    txa
+    clc
+    adc #5
+    // SCREEN[c] = x+5
+    // x+5 is a loop invariant computation
+    sta SCREEN,y
+    // for(char c=0;c<40;c++)
+    iny
+    jmp __b1
+}
diff --git a/src/test/ref/strength-reduction-1.cfg b/src/test/ref/strength-reduction-1.cfg
new file mode 100644
index 000000000..921cef07d
--- /dev/null
+++ b/src/test/ref/strength-reduction-1.cfg
@@ -0,0 +1,17 @@
+
+void main()
+main: scope:[main]  from
+  [0] main::x#0 = *SCREEN
+  to:main::@1
+main::@1: scope:[main]  from main main::@2
+  [1] main::c#2 = phi( main/0, main::@2/main::c#1 )
+  [2] if(main::c#2<$28) goto main::@2
+  to:main::@return
+main::@return: scope:[main]  from main::@1
+  [3] return 
+  to:@return
+main::@2: scope:[main]  from main::@1
+  [4] main::$1 = main::x#0 + 5
+  [5] SCREEN[main::c#2] = main::$1
+  [6] main::c#1 = ++ main::c#2
+  to:main::@1
diff --git a/src/test/ref/strength-reduction-1.log b/src/test/ref/strength-reduction-1.log
new file mode 100644
index 000000000..10aacf3cc
--- /dev/null
+++ b/src/test/ref/strength-reduction-1.log
@@ -0,0 +1,266 @@
+Inlined call call __init 
+
+CONTROL FLOW GRAPH SSA
+
+void main()
+main: scope:[main]  from __start::@1
+  main::x#0 = *SCREEN
+  main::c#0 = 0
+  to:main::@1
+main::@1: scope:[main]  from main main::@2
+  main::x#2 = phi( main/main::x#0, main::@2/main::x#1 )
+  main::c#2 = phi( main/main::c#0, main::@2/main::c#1 )
+  main::$0 = main::c#2 < $28
+  if(main::$0) goto main::@2
+  to:main::@return
+main::@2: scope:[main]  from main::@1
+  main::c#3 = phi( main::@1/main::c#2 )
+  main::x#1 = phi( main::@1/main::x#2 )
+  main::$1 = main::x#1 + 5
+  SCREEN[main::c#3] = main::$1
+  main::c#1 = ++ main::c#3
+  to:main::@1
+main::@return: scope:[main]  from main::@1
+  return 
+  to:@return
+
+void __start()
+__start: scope:[__start]  from
+  to:__start::__init1
+__start::__init1: scope:[__start]  from __start
+  to:__start::@1
+__start::@1: scope:[__start]  from __start::__init1
+  call main 
+  to:__start::@2
+__start::@2: scope:[__start]  from __start::@1
+  to:__start::@return
+__start::@return: scope:[__start]  from __start::@2
+  return 
+  to:@return
+
+SYMBOL TABLE SSA
+const byte* SCREEN = (byte*)$400
+void __start()
+void main()
+bool~ main::$0
+number~ main::$1
+byte main::c
+byte main::c#0
+byte main::c#1
+byte main::c#2
+byte main::c#3
+byte main::x
+byte main::x#0
+byte main::x#1
+byte main::x#2
+
+Adding number conversion cast (unumber) $28 in main::$0 = main::c#2 < $28
+Adding number conversion cast (unumber) 5 in main::$1 = main::x#1 + 5
+Adding number conversion cast (unumber) main::$1 in main::$1 = main::x#1 + (unumber)5
+Successful SSA optimization PassNAddNumberTypeConversions
+Simplifying constant pointer cast (byte*) 1024
+Simplifying constant integer cast $28
+Simplifying constant integer cast 5
+Successful SSA optimization PassNCastSimplification
+Finalized unsigned number type $28
+Finalized unsigned number type 5
+Successful SSA optimization PassNFinalizeNumberTypeConversions
+Inferred type updated to byte in main::$1 = main::x#1 + 5
+Alias main::x#1 = main::x#2 
+Alias main::c#2 = main::c#3 
+Successful SSA optimization Pass2AliasElimination
+Identical Phi Values main::x#1 main::x#0
+Successful SSA optimization Pass2IdenticalPhiElimination
+Simple Condition main::$0 [4] if(main::c#2<$28) goto main::@2
+Successful SSA optimization Pass2ConditionalJumpSimplification
+Constant main::c#0 = 0
+Successful SSA optimization Pass2ConstantIdentification
+Removing unused procedure __start
+Removing unused procedure block __start
+Removing unused procedure block __start::__init1
+Removing unused procedure block __start::@1
+Removing unused procedure block __start::@2
+Removing unused procedure block __start::@return
+Successful SSA optimization PassNEliminateEmptyStart
+Inlining constant with var siblings main::c#0
+Constant inlined main::c#0 = 0
+Successful SSA optimization Pass2ConstantInlining
+CALL GRAPH
+
+Created 1 initial phi equivalence classes
+Coalesced [7] main::c#4 = main::c#1
+Coalesced down to 1 phi equivalence classes
+
+FINAL CONTROL FLOW GRAPH
+
+void main()
+main: scope:[main]  from
+  [0] main::x#0 = *SCREEN
+  to:main::@1
+main::@1: scope:[main]  from main main::@2
+  [1] main::c#2 = phi( main/0, main::@2/main::c#1 )
+  [2] if(main::c#2<$28) goto main::@2
+  to:main::@return
+main::@return: scope:[main]  from main::@1
+  [3] return 
+  to:@return
+main::@2: scope:[main]  from main::@1
+  [4] main::$1 = main::x#0 + 5
+  [5] SCREEN[main::c#2] = main::$1
+  [6] main::c#1 = ++ main::c#2
+  to:main::@1
+
+
+VARIABLE REGISTER WEIGHTS
+void main()
+byte~ main::$1 22.0
+byte main::c
+byte main::c#1 22.0
+byte main::c#2 11.0
+byte main::x
+byte main::x#0 2.1666666666666665
+
+Initial phi equivalence classes
+[ main::c#2 main::c#1 ]
+Added variable main::x#0 to live range equivalence class [ main::x#0 ]
+Added variable main::$1 to live range equivalence class [ main::$1 ]
+Complete equivalence classes
+[ main::c#2 main::c#1 ]
+[ main::x#0 ]
+[ main::$1 ]
+Allocated zp[1]:2 [ main::c#2 main::c#1 ]
+Allocated zp[1]:3 [ main::x#0 ]
+Allocated zp[1]:4 [ main::$1 ]
+REGISTER UPLIFT POTENTIAL REGISTERS
+Potential registers zp[1]:2 [ main::c#2 main::c#1 ] : zp[1]:2 , reg byte a , reg byte x , reg byte y , 
+Potential registers zp[1]:3 [ main::x#0 ] : zp[1]:3 , reg byte a , reg byte x , reg byte y , 
+Potential registers zp[1]:4 [ main::$1 ] : zp[1]:4 , reg byte a , reg byte x , reg byte y , 
+
+REGISTER UPLIFT SCOPES
+Uplift Scope [main] 33: zp[1]:2 [ main::c#2 main::c#1 ] 22: zp[1]:4 [ main::$1 ] 2.17: zp[1]:3 [ main::x#0 ] 
+Uplift Scope [] 
+
+Uplifting [main] best 295 combination reg byte y [ main::c#2 main::c#1 ] reg byte a [ main::$1 ] reg byte x [ main::x#0 ] 
+Uplifting [] best 295 combination 
+
+ASSEMBLER BEFORE OPTIMIZATION
+  // File Comments
+// Test loop invariant computation detection
+// http://www.cs.toronto.edu/~pekhimenko/courses/cscd70-w18/docs/Lecture%205%20[LICM%20and%20Strength%20Reduction]%2002.08.2018.pdf
+  // Upstart
+.pc = $801 "Basic"
+:BasicUpstart(main)
+.pc = $80d "Program"
+  // Global Constants & labels
+  .label SCREEN = $400
+  // main
+main: {
+    // [0] main::x#0 = *SCREEN -- vbuxx=_deref_pbuc1 
+    ldx SCREEN
+    // [1] phi from main to main::@1 [phi:main->main::@1]
+  __b1_from_main:
+    // [1] phi main::c#2 = 0 [phi:main->main::@1#0] -- vbuyy=vbuc1 
+    ldy #0
+    jmp __b1
+    // main::@1
+  __b1:
+    // [2] if(main::c#2<$28) goto main::@2 -- vbuyy_lt_vbuc1_then_la1 
+    cpy #$28
+    bcc __b2
+    jmp __breturn
+    // main::@return
+  __breturn:
+    // [3] return 
+    rts
+    // main::@2
+  __b2:
+    // [4] main::$1 = main::x#0 + 5 -- vbuaa=vbuxx_plus_vbuc1 
+    txa
+    clc
+    adc #5
+    // [5] SCREEN[main::c#2] = main::$1 -- pbuc1_derefidx_vbuyy=vbuaa 
+    // x+5 is a loop invariant computation
+    sta SCREEN,y
+    // [6] main::c#1 = ++ main::c#2 -- vbuyy=_inc_vbuyy 
+    iny
+    // [1] phi from main::@2 to main::@1 [phi:main::@2->main::@1]
+  __b1_from___b2:
+    // [1] phi main::c#2 = main::c#1 [phi:main::@2->main::@1#0] -- register_copy 
+    jmp __b1
+}
+  // File Data
+
+ASSEMBLER OPTIMIZATIONS
+Removing instruction jmp __b1
+Removing instruction jmp __breturn
+Succesful ASM optimization Pass5NextJumpElimination
+Removing instruction __b1_from_main:
+Removing instruction __breturn:
+Removing instruction __b1_from___b2:
+Succesful ASM optimization Pass5UnusedLabelElimination
+
+FINAL SYMBOL TABLE
+const byte* SCREEN = (byte*) 1024
+void main()
+byte~ main::$1 reg byte a 22.0
+byte main::c
+byte main::c#1 reg byte y 22.0
+byte main::c#2 reg byte y 11.0
+byte main::x
+byte main::x#0 reg byte x 2.1666666666666665
+
+reg byte y [ main::c#2 main::c#1 ]
+reg byte x [ main::x#0 ]
+reg byte a [ main::$1 ]
+
+
+FINAL ASSEMBLER
+Score: 235
+
+  // File Comments
+// Test loop invariant computation detection
+// http://www.cs.toronto.edu/~pekhimenko/courses/cscd70-w18/docs/Lecture%205%20[LICM%20and%20Strength%20Reduction]%2002.08.2018.pdf
+  // Upstart
+.pc = $801 "Basic"
+:BasicUpstart(main)
+.pc = $80d "Program"
+  // Global Constants & labels
+  .label SCREEN = $400
+  // main
+main: {
+    // x = *SCREEN
+    // [0] main::x#0 = *SCREEN -- vbuxx=_deref_pbuc1 
+    ldx SCREEN
+    // [1] phi from main to main::@1 [phi:main->main::@1]
+    // [1] phi main::c#2 = 0 [phi:main->main::@1#0] -- vbuyy=vbuc1 
+    ldy #0
+    // main::@1
+  __b1:
+    // for(char c=0;c<40;c++)
+    // [2] if(main::c#2<$28) goto main::@2 -- vbuyy_lt_vbuc1_then_la1 
+    cpy #$28
+    bcc __b2
+    // main::@return
+    // }
+    // [3] return 
+    rts
+    // main::@2
+  __b2:
+    // x+5
+    // [4] main::$1 = main::x#0 + 5 -- vbuaa=vbuxx_plus_vbuc1 
+    txa
+    clc
+    adc #5
+    // SCREEN[c] = x+5
+    // [5] SCREEN[main::c#2] = main::$1 -- pbuc1_derefidx_vbuyy=vbuaa 
+    // x+5 is a loop invariant computation
+    sta SCREEN,y
+    // for(char c=0;c<40;c++)
+    // [6] main::c#1 = ++ main::c#2 -- vbuyy=_inc_vbuyy 
+    iny
+    // [1] phi from main::@2 to main::@1 [phi:main::@2->main::@1]
+    // [1] phi main::c#2 = main::c#1 [phi:main::@2->main::@1#0] -- register_copy 
+    jmp __b1
+}
+  // File Data
+
diff --git a/src/test/ref/strength-reduction-1.sym b/src/test/ref/strength-reduction-1.sym
new file mode 100644
index 000000000..bcbd2e112
--- /dev/null
+++ b/src/test/ref/strength-reduction-1.sym
@@ -0,0 +1,12 @@
+const byte* SCREEN = (byte*) 1024
+void main()
+byte~ main::$1 reg byte a 22.0
+byte main::c
+byte main::c#1 reg byte y 22.0
+byte main::c#2 reg byte y 11.0
+byte main::x
+byte main::x#0 reg byte x 2.1666666666666665
+
+reg byte y [ main::c#2 main::c#1 ]
+reg byte x [ main::x#0 ]
+reg byte a [ main::$1 ]