Fixed NPE when using booleans in if()/while(). Closes #152

src/main/java/dk/camelot64/kickc/passes/Pass2ConditionalAndOrRewriting.java

@@ -54,18 +54,20 @@ public class Pass2ConditionalAndOrRewriting extends Pass2SsaOptimization {
                   if(conditionRValue instanceof VariableRef && usages.get(conditionRValue).size() == 1) {
                      VariableRef conditionVar = (VariableRef) conditionRValue;
                      StatementAssignment conditionAssignment = assignments.get(conditionVar);
-                     if(Operators.LOGIC_AND.equals(conditionAssignment.getOperator())) {
-                        // Found if() with logical && condition - rewrite to if(c1) if(c2) { xx }
-                        rewriteLogicAnd(block, conditional, conditionAssignment);
-                        return conditionVar;
-                     } else if(Operators.LOGIC_OR.equals(conditionAssignment.getOperator())) {
-                        // Found if() with logical || condition - rewrite to if(c1) goto x else if(c2) goto x else goto end, x:{ xx } end:
-                        rewriteLogicOr(block, conditional, conditionAssignment);
-                        return conditionVar;
-                     } else if(Operators.LOGIC_NOT.equals(conditionAssignment.getOperator())) {
-                        // Found if() with logical ! condition - rewrite to if(!c1) goto x else goto end, x:{ xx } end:
-                        rewriteLogicNot(block, conditional, conditionAssignment);
-                        return conditionVar;
+                     if(conditionAssignment!=null) {
+                        if(Operators.LOGIC_AND.equals(conditionAssignment.getOperator())) {
+                           // Found if() with logical && condition - rewrite to if(c1) if(c2) { xx }
+                           rewriteLogicAnd(block, conditional, conditionAssignment);
+                           return conditionVar;
+                        } else if(Operators.LOGIC_OR.equals(conditionAssignment.getOperator())) {
+                           // Found if() with logical || condition - rewrite to if(c1) goto x else if(c2) goto x else goto end, x:{ xx } end:
+                           rewriteLogicOr(block, conditional, conditionAssignment);
+                           return conditionVar;
+                        } else if(Operators.LOGIC_NOT.equals(conditionAssignment.getOperator())) {
+                           // Found if() with logical ! condition - rewrite to if(!c1) goto x else goto end, x:{ xx } end:
+                           rewriteLogicNot(block, conditional, conditionAssignment);
+                           return conditionVar;
+                        }
                      }
                   }
                }

src/main/java/dk/camelot64/kickc/passes/Pass2ConditionalJumpSimplification.java

@@ -43,7 +43,7 @@ public class Pass2ConditionalJumpSimplification extends Pass2SsaOptimization {
                if(conditionRValue instanceof VariableRef && usages.get(conditionRValue).size() == 1) {
                   VariableRef conditionVar = (VariableRef) conditionRValue;
                   StatementAssignment conditionAssignment = assignments.get(conditionVar);
-                  if(conditionAssignment.getOperator() != null) {
+                  if(conditionAssignment!=null && conditionAssignment.getOperator() != null) {
                      switch(conditionAssignment.getOperator().getOperator()) {
                         case "==":
                         case "<>":

src/test/java/dk/camelot64/kickc/test/TestPrograms.java

@@ -32,6 +32,11 @@ public class TestPrograms {
    public TestPrograms() {
    }
 
+   @Test
+   public void testBoolNullPointerException() throws IOException, URISyntaxException {
+      compileAndCompare("bool-nullpointer-exception");
+   }
+
    @Test
    public void testSignedWordMinusByte() throws IOException, URISyntaxException {
       compileAndCompare("test-signed-word-minus-byte");

src/test/kc/bool-nullpointer-exception.kc

@@ -0,0 +1,11 @@
+// Some bool code that causes a NullPointerException
+
+bool framedone = true;
+
+void main() {
+    while(true) {
+        while(!framedone) {}
+        framedone = false;
+    }
+}
+

src/test/ref/bool-nullpointer-exception.asm

@@ -0,0 +1,14 @@
+// Some bool code that causes a NullPointerException
+.pc = $801 "Basic"
+:BasicUpstart(main)
+.pc = $80d "Program"
+main: {
+    lda #1
+    jmp b4
+  b1:
+    lda #0
+  b4:
+    cmp #0
+    bne b1
+    jmp b4
+}

src/test/ref/bool-nullpointer-exception.cfg

@@ -0,0 +1,18 @@
+@begin: scope:[]  from
+  [0] phi()
+  to:@1
+@1: scope:[]  from @begin
+  [1] phi()
+  [2] call main 
+  to:@end
+@end: scope:[]  from @1
+  [3] phi()
+main: scope:[main]  from @1
+  [4] phi()
+  to:main::@1
+main::@1: scope:[main]  from main main::@4
+  [5] (bool) framedone#2 ← phi( main/true main::@4/false )
+  to:main::@4
+main::@4: scope:[main]  from main::@1 main::@4
+  [6] if((bool) framedone#2) goto main::@1
+  to:main::@4

src/test/ref/bool-nullpointer-exception.log

@@ -0,0 +1,325 @@
+
+CONTROL FLOW GRAPH SSA
+@begin: scope:[]  from
+  (bool) framedone#0 ← true
+  to:@1
+main: scope:[main]  from @1
+  (bool) framedone#11 ← phi( @1/(bool) framedone#10 )
+  to:main::@1
+main::@1: scope:[main]  from main main::@6
+  (bool) framedone#9 ← phi( main/(bool) framedone#11 main::@6/(bool) framedone#1 )
+  if(true) goto main::@2
+  to:main::@return
+main::@2: scope:[main]  from main::@1
+  (bool) framedone#7 ← phi( main::@1/(bool) framedone#9 )
+  to:main::@4
+main::@4: scope:[main]  from main::@2 main::@5
+  (bool) framedone#4 ← phi( main::@2/(bool) framedone#7 main::@5/(bool) framedone#8 )
+  (bool~) main::$0 ← ! (bool) framedone#4
+  if((bool~) main::$0) goto main::@5
+  to:main::@6
+main::@5: scope:[main]  from main::@4
+  (bool) framedone#8 ← phi( main::@4/(bool) framedone#4 )
+  to:main::@4
+main::@6: scope:[main]  from main::@4
+  (bool) framedone#1 ← false
+  to:main::@1
+main::@return: scope:[main]  from main::@1
+  (bool) framedone#5 ← phi( main::@1/(bool) framedone#9 )
+  (bool) framedone#2 ← (bool) framedone#5
+  return 
+  to:@return
+@1: scope:[]  from @begin
+  (bool) framedone#10 ← phi( @begin/(bool) framedone#0 )
+  call main 
+  to:@2
+@2: scope:[]  from @1
+  (bool) framedone#6 ← phi( @1/(bool) framedone#2 )
+  (bool) framedone#3 ← (bool) framedone#6
+  to:@end
+@end: scope:[]  from @2
+
+SYMBOL TABLE SSA
+(label) @1
+(label) @2
+(label) @begin
+(label) @end
+(bool) framedone
+(bool) framedone#0
+(bool) framedone#1
+(bool) framedone#10
+(bool) framedone#11
+(bool) framedone#2
+(bool) framedone#3
+(bool) framedone#4
+(bool) framedone#5
+(bool) framedone#6
+(bool) framedone#7
+(bool) framedone#8
+(bool) framedone#9
+(void()) main()
+(bool~) main::$0
+(label) main::@1
+(label) main::@2
+(label) main::@4
+(label) main::@5
+(label) main::@6
+(label) main::@return
+
+Alias (bool) framedone#2 = (bool) framedone#7 (bool) framedone#9 (bool) framedone#5 
+Alias (bool) framedone#4 = (bool) framedone#8 
+Alias (bool) framedone#0 = (bool) framedone#10 
+Alias (bool) framedone#3 = (bool) framedone#6 
+Successful SSA optimization Pass2AliasElimination
+Self Phi Eliminated (bool) framedone#4
+Successful SSA optimization Pass2SelfPhiElimination
+Redundant Phi (bool) framedone#11 (bool) framedone#0
+Redundant Phi (bool) framedone#4 (bool) framedone#2
+Redundant Phi (bool) framedone#3 (bool) framedone#2
+Successful SSA optimization Pass2RedundantPhiElimination
+Rewriting ! if()-condition to reversed if() [6] (bool~) main::$0 ← ! (bool) framedone#2
+Successful SSA optimization Pass2ConditionalAndOrRewriting
+Constant (const bool) framedone#0 = true
+Constant (const bool) framedone#1 = false
+Successful SSA optimization Pass2ConstantIdentification
+if() condition always true - replacing block destination [1] if(true) goto main::@2
+Successful SSA optimization Pass2ConstantIfs
+Removing unused block main::@return
+Successful SSA optimization Pass2EliminateUnusedBlocks
+Culled Empty Block (label) main::@2
+Culled Empty Block (label) main::@5
+Culled Empty Block (label) main::@6
+Culled Empty Block (label) @2
+Successful SSA optimization Pass2CullEmptyBlocks
+Inlining constant with var siblings (const bool) framedone#0
+Inlining constant with var siblings (const bool) framedone#1
+Constant inlined framedone#1 = false
+Constant inlined framedone#0 = true
+Successful SSA optimization Pass2ConstantInlining
+Adding NOP phi() at start of @begin
+Adding NOP phi() at start of @1
+Adding NOP phi() at start of @end
+Adding NOP phi() at start of main
+CALL GRAPH
+Calls in [] to main:2 
+
+Created 1 initial phi equivalence classes
+Coalesced down to 1 phi equivalence classes
+Adding NOP phi() at start of @begin
+Adding NOP phi() at start of @1
+Adding NOP phi() at start of @end
+Adding NOP phi() at start of main
+
+FINAL CONTROL FLOW GRAPH
+@begin: scope:[]  from
+  [0] phi()
+  to:@1
+@1: scope:[]  from @begin
+  [1] phi()
+  [2] call main 
+  to:@end
+@end: scope:[]  from @1
+  [3] phi()
+main: scope:[main]  from @1
+  [4] phi()
+  to:main::@1
+main::@1: scope:[main]  from main main::@4
+  [5] (bool) framedone#2 ← phi( main/true main::@4/false )
+  to:main::@4
+main::@4: scope:[main]  from main::@1 main::@4
+  [6] if((bool) framedone#2) goto main::@1
+  to:main::@4
+
+
+VARIABLE REGISTER WEIGHTS
+(bool) framedone
+(bool) framedone#2 50.5
+(void()) main()
+
+Initial phi equivalence classes
+[ framedone#2 ]
+Complete equivalence classes
+[ framedone#2 ]
+Allocated zp ZP_BOOL:2 [ framedone#2 ]
+
+INITIAL ASM
+//SEG0 File Comments
+// Some bool code that causes a NullPointerException
+//SEG1 Basic Upstart
+.pc = $801 "Basic"
+:BasicUpstart(bbegin)
+.pc = $80d "Program"
+//SEG2 Global Constants & labels
+  .label framedone = 2
+//SEG3 @begin
+bbegin:
+//SEG4 [1] phi from @begin to @1 [phi:@begin->@1]
+b1_from_bbegin:
+  jmp b1
+//SEG5 @1
+b1:
+//SEG6 [2] call main 
+//SEG7 [4] phi from @1 to main [phi:@1->main]
+main_from_b1:
+  jsr main
+//SEG8 [3] phi from @1 to @end [phi:@1->@end]
+bend_from_b1:
+  jmp bend
+//SEG9 @end
+bend:
+//SEG10 main
+main: {
+  //SEG11 [5] phi from main to main::@1 [phi:main->main::@1]
+  b1_from_main:
+  //SEG12 [5] phi (bool) framedone#2 = true [phi:main->main::@1#0] -- vboz1=vboc1 
+    lda #1
+    sta framedone
+    jmp b1
+  //SEG13 [5] phi from main::@4 to main::@1 [phi:main::@4->main::@1]
+  b1_from_b4:
+  //SEG14 [5] phi (bool) framedone#2 = false [phi:main::@4->main::@1#0] -- vboz1=vboc1 
+    lda #0
+    sta framedone
+    jmp b1
+  //SEG15 main::@1
+  b1:
+    jmp b4
+  //SEG16 main::@4
+  b4:
+  //SEG17 [6] if((bool) framedone#2) goto main::@1 -- vboz1_then_la1 
+    lda framedone
+    cmp #0
+    bne b1_from_b4
+    jmp b4
+}
+
+REGISTER UPLIFT POTENTIAL REGISTERS
+Potential registers zp ZP_BOOL:2 [ framedone#2 ] : zp ZP_BOOL:2 , reg byte a , 
+
+REGISTER UPLIFT SCOPES
+Uplift Scope [] 50.5: zp ZP_BOOL:2 [ framedone#2 ] 
+Uplift Scope [main] 
+
+Uplifting [] best 892 combination reg byte a [ framedone#2 ] 
+Uplifting [main] best 892 combination 
+
+ASSEMBLER BEFORE OPTIMIZATION
+//SEG0 File Comments
+// Some bool code that causes a NullPointerException
+//SEG1 Basic Upstart
+.pc = $801 "Basic"
+:BasicUpstart(bbegin)
+.pc = $80d "Program"
+//SEG2 Global Constants & labels
+//SEG3 @begin
+bbegin:
+//SEG4 [1] phi from @begin to @1 [phi:@begin->@1]
+b1_from_bbegin:
+  jmp b1
+//SEG5 @1
+b1:
+//SEG6 [2] call main 
+//SEG7 [4] phi from @1 to main [phi:@1->main]
+main_from_b1:
+  jsr main
+//SEG8 [3] phi from @1 to @end [phi:@1->@end]
+bend_from_b1:
+  jmp bend
+//SEG9 @end
+bend:
+//SEG10 main
+main: {
+  //SEG11 [5] phi from main to main::@1 [phi:main->main::@1]
+  b1_from_main:
+  //SEG12 [5] phi (bool) framedone#2 = true [phi:main->main::@1#0] -- vboaa=vboc1 
+    lda #1
+    jmp b1
+  //SEG13 [5] phi from main::@4 to main::@1 [phi:main::@4->main::@1]
+  b1_from_b4:
+  //SEG14 [5] phi (bool) framedone#2 = false [phi:main::@4->main::@1#0] -- vboaa=vboc1 
+    lda #0
+    jmp b1
+  //SEG15 main::@1
+  b1:
+    jmp b4
+  //SEG16 main::@4
+  b4:
+  //SEG17 [6] if((bool) framedone#2) goto main::@1 -- vboaa_then_la1 
+    cmp #0
+    bne b1_from_b4
+    jmp b4
+}
+
+ASSEMBLER OPTIMIZATIONS
+Removing instruction jmp b1
+Removing instruction jmp bend
+Removing instruction jmp b1
+Removing instruction jmp b4
+Succesful ASM optimization Pass5NextJumpElimination
+Replacing label b1 with b4
+Removing instruction b1_from_bbegin:
+Removing instruction b1:
+Removing instruction main_from_b1:
+Removing instruction bend_from_b1:
+Removing instruction b1:
+Succesful ASM optimization Pass5RedundantLabelElimination
+Removing instruction bend:
+Removing instruction b1_from_main:
+Succesful ASM optimization Pass5UnusedLabelElimination
+Updating BasicUpstart to call main directly
+Removing instruction jsr main
+Succesful ASM optimization Pass5SkipBegin
+Relabelling long label b1_from_b4 to b1
+Succesful ASM optimization Pass5RelabelLongLabels
+Removing instruction bbegin:
+Succesful ASM optimization Pass5UnusedLabelElimination
+
+FINAL SYMBOL TABLE
+(label) @1
+(label) @begin
+(label) @end
+(bool) framedone
+(bool) framedone#2 reg byte a 50.5
+(void()) main()
+(label) main::@1
+(label) main::@4
+
+reg byte a [ framedone#2 ]
+
+
+FINAL ASSEMBLER
+Score: 820
+
+//SEG0 File Comments
+// Some bool code that causes a NullPointerException
+//SEG1 Basic Upstart
+.pc = $801 "Basic"
+:BasicUpstart(main)
+.pc = $80d "Program"
+//SEG2 Global Constants & labels
+//SEG3 @begin
+//SEG4 [1] phi from @begin to @1 [phi:@begin->@1]
+//SEG5 @1
+//SEG6 [2] call main 
+//SEG7 [4] phi from @1 to main [phi:@1->main]
+//SEG8 [3] phi from @1 to @end [phi:@1->@end]
+//SEG9 @end
+//SEG10 main
+main: {
+  //SEG11 [5] phi from main to main::@1 [phi:main->main::@1]
+  //SEG12 [5] phi (bool) framedone#2 = true [phi:main->main::@1#0] -- vboaa=vboc1 
+    lda #1
+    jmp b4
+  //SEG13 [5] phi from main::@4 to main::@1 [phi:main::@4->main::@1]
+  b1:
+  //SEG14 [5] phi (bool) framedone#2 = false [phi:main::@4->main::@1#0] -- vboaa=vboc1 
+    lda #0
+  //SEG15 main::@1
+  //SEG16 main::@4
+  b4:
+  //SEG17 [6] if((bool) framedone#2) goto main::@1 -- vboaa_then_la1 
+    cmp #0
+    bne b1
+    jmp b4
+}
+

src/test/ref/bool-nullpointer-exception.sym

@@ -0,0 +1,10 @@
+(label) @1
+(label) @begin
+(label) @end
+(bool) framedone
+(bool) framedone#2 reg byte a 50.5
+(void()) main()
+(label) main::@1
+(label) main::@4
+
+reg byte a [ framedone#2 ]