Better error when assigning an undeclared variable. Closes #141

src/main/java/dk/camelot64/kickc/model/values/ForwardVariableRef.java

@@ -4,10 +4,10 @@ import dk.camelot64.kickc.model.Program;
 
 /** An unresolved forward variable reference.
  * Created in {@link dk.camelot64.kickc.passes.Pass0GenerateStatementSequence}.
- * Resolved in {@link }.
+ * Resolved in {@link dk.camelot64.kickc.passes.Pass1ResolveForwardReferences}.
  * After this point they are never present in the program.
  * */
-public class ForwardVariableRef implements RValue {
+public class ForwardVariableRef implements LValue {
 
    /** The referenced unresolved variable name. */
    private String name;

src/main/java/dk/camelot64/kickc/model/values/LValue.java

@@ -8,7 +8,7 @@ public interface LValue extends RValue {
    /**
     * Singleton signalling that an RValue is never assigned and can safely be discarded as rvalue in phi-functions.
     */
-   public static RValue VOID = new RValue() {
+   RValue VOID = new RValue() {
 
       @Override
       public String toString() {

src/main/java/dk/camelot64/kickc/passes/Pass1ResolveForwardReferences.java

@@ -5,7 +5,6 @@ import dk.camelot64.kickc.model.Program;
 import dk.camelot64.kickc.model.iterator.ProgramValueIterator;
 import dk.camelot64.kickc.model.symbols.Scope;
 import dk.camelot64.kickc.model.symbols.Symbol;
-import dk.camelot64.kickc.model.symbols.Variable;
 import dk.camelot64.kickc.model.values.ForwardVariableRef;
 import dk.camelot64.kickc.model.values.RValue;
 

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

@@ -114,6 +114,11 @@ public class TestPrograms {
 //      compileAndCompare("complex/robozzle64/robozzle64");
 //   }
 
+   //@Test
+   //public void testTravisGame() throws IOException, URISyntaxException {
+   //   compileAndCompare("complex/travis/game");
+   //}
+
    @Test
    public void testTetrisSprites() throws IOException, URISyntaxException {
       compileAndCompare("complex/tetris/test-sprites");
@@ -466,6 +471,11 @@ public class TestPrograms {
       compileAndCompare("var-forward-problem");
    }
 
+   @Test
+   public void testVarForwardProblem2() throws IOException, URISyntaxException {
+      compileAndCompare("var-forward-problem2");
+   }
+
    @Test
    public void testInlineString3() throws IOException, URISyntaxException {
       compileAndCompare("inline-string-3");
@@ -1056,6 +1066,11 @@ public class TestPrograms {
       assertError("useundeclared", "Unknown variable");
    }
 
+   @Test
+   public void testassignUndeclared() throws IOException, URISyntaxException {
+      assertError("assignundeclared", "Unknown variable");
+   }
+
    @Test
    public void testUseUninitialized() throws IOException, URISyntaxException {
       assertError("useuninitialized", "Variable used before being defined");

src/test/kc/assignundeclared.kc

@@ -0,0 +1,4 @@
+// Assign an undeclared variable - should fail gracefully
+void main() {
+   s = 1;
+}

src/test/kc/var-forward-problem2.kc

@@ -0,0 +1,10 @@
+// Illustrates the problem with variable forward references not working
+
+void main() {
+    screen = $400;
+    b = 'a';
+    *screen = b;
+}
+
+byte* screen;
+byte b;

src/test/ref/var-forward-problem2.asm

@@ -0,0 +1,11 @@
+// Illustrates the problem with variable forward references not working
+.pc = $801 "Basic"
+:BasicUpstart(main)
+.pc = $80d "Program"
+  .label screen = $400
+  .const b = 'a'
+main: {
+    lda #b
+    sta screen
+    rts
+}

src/test/ref/var-forward-problem2.cfg

@@ -0,0 +1,15 @@
+@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] *((const byte*) screen#0) ← (const byte) b#0
+  to:main::@return
+main::@return: scope:[main]  from main
+  [5] return 
+  to:@return

src/test/ref/var-forward-problem2.log

@@ -0,0 +1,255 @@
+Resolved forward reference screen to (byte*) screen
+Resolved forward reference b to (byte) b
+Resolved forward reference b to (byte) b
+Resolved forward reference screen to (byte*) screen
+
+CONTROL FLOW GRAPH SSA
+@begin: scope:[]  from
+  (byte) b#6 ← phi( )
+  (byte*) screen#6 ← phi( )
+  to:@1
+main: scope:[main]  from @1
+  (byte*) screen#0 ← ((byte*)) (word/signed word/dword/signed dword) 1024
+  (byte) b#0 ← (byte) 'a'
+  *((byte*) screen#0) ← (byte) b#0
+  to:main::@return
+main::@return: scope:[main]  from main
+  (byte) b#3 ← phi( main/(byte) b#0 )
+  (byte*) screen#3 ← phi( main/(byte*) screen#0 )
+  (byte*) screen#1 ← (byte*) screen#3
+  (byte) b#1 ← (byte) b#3
+  return 
+  to:@return
+@1: scope:[]  from @begin
+  (byte) b#5 ← phi( @begin/(byte) b#6 )
+  (byte*) screen#5 ← phi( @begin/(byte*) screen#6 )
+  call main 
+  to:@2
+@2: scope:[]  from @1
+  (byte) b#4 ← phi( @1/(byte) b#1 )
+  (byte*) screen#4 ← phi( @1/(byte*) screen#1 )
+  (byte*) screen#2 ← (byte*) screen#4
+  (byte) b#2 ← (byte) b#4
+  to:@end
+@end: scope:[]  from @2
+
+SYMBOL TABLE SSA
+(label) @1
+(label) @2
+(label) @begin
+(label) @end
+(byte) b
+(byte) b#0
+(byte) b#1
+(byte) b#2
+(byte) b#3
+(byte) b#4
+(byte) b#5
+(byte) b#6
+(void()) main()
+(label) main::@return
+(byte*) screen
+(byte*) screen#0
+(byte*) screen#1
+(byte*) screen#2
+(byte*) screen#3
+(byte*) screen#4
+(byte*) screen#5
+(byte*) screen#6
+
+Alias (byte*) screen#0 = (byte*) screen#3 (byte*) screen#1 
+Alias (byte) b#0 = (byte) b#3 (byte) b#1 
+Alias (byte*) screen#5 = (byte*) screen#6 
+Alias (byte) b#5 = (byte) b#6 
+Alias (byte*) screen#2 = (byte*) screen#4 
+Alias (byte) b#2 = (byte) b#4 
+Successful SSA optimization Pass2AliasElimination
+Redundant Phi (byte*) screen#5 VOID
+Redundant Phi (byte) b#5 VOID
+Redundant Phi (byte*) screen#2 (byte*) screen#0
+Redundant Phi (byte) b#2 (byte) b#0
+Successful SSA optimization Pass2RedundantPhiElimination
+Constant (const byte*) screen#0 = ((byte*))1024
+Constant (const byte) b#0 = 'a'
+Successful SSA optimization Pass2ConstantIdentification
+Culled Empty Block (label) @2
+Successful SSA optimization Pass2CullEmptyBlocks
+Adding NOP phi() at start of @begin
+Adding NOP phi() at start of @1
+Adding NOP phi() at start of @end
+CALL GRAPH
+Calls in [] to main:2 
+
+Created 0 initial phi equivalence classes
+Coalesced down to 0 phi equivalence classes
+Adding NOP phi() at start of @begin
+Adding NOP phi() at start of @1
+Adding NOP phi() at start of @end
+
+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] *((const byte*) screen#0) ← (const byte) b#0
+  to:main::@return
+main::@return: scope:[main]  from main
+  [5] return 
+  to:@return
+
+
+VARIABLE REGISTER WEIGHTS
+(byte) b
+(void()) main()
+(byte*) screen
+
+Initial phi equivalence classes
+Complete equivalence classes
+
+INITIAL ASM
+//SEG0 File Comments
+// Illustrates the problem with variable forward references not working
+//SEG1 Basic Upstart
+.pc = $801 "Basic"
+:BasicUpstart(bbegin)
+.pc = $80d "Program"
+//SEG2 Global Constants & labels
+  .label screen = $400
+  .const b = 'a'
+//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 
+  jsr main
+//SEG7 [3] phi from @1 to @end [phi:@1->@end]
+bend_from_b1:
+  jmp bend
+//SEG8 @end
+bend:
+//SEG9 main
+main: {
+  //SEG10 [4] *((const byte*) screen#0) ← (const byte) b#0 -- _deref_pbuc1=vbuc2 
+    lda #b
+    sta screen
+    jmp breturn
+  //SEG11 main::@return
+  breturn:
+  //SEG12 [5] return 
+    rts
+}
+
+REGISTER UPLIFT POTENTIAL REGISTERS
+Statement [4] *((const byte*) screen#0) ← (const byte) b#0 [ ] ( main:2 [ ] ) always clobbers reg byte a 
+
+REGISTER UPLIFT SCOPES
+Uplift Scope [main] 
+Uplift Scope [] 
+
+Uplifting [main] best 27 combination 
+Uplifting [] best 27 combination 
+
+ASSEMBLER BEFORE OPTIMIZATION
+//SEG0 File Comments
+// Illustrates the problem with variable forward references not working
+//SEG1 Basic Upstart
+.pc = $801 "Basic"
+:BasicUpstart(bbegin)
+.pc = $80d "Program"
+//SEG2 Global Constants & labels
+  .label screen = $400
+  .const b = 'a'
+//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 
+  jsr main
+//SEG7 [3] phi from @1 to @end [phi:@1->@end]
+bend_from_b1:
+  jmp bend
+//SEG8 @end
+bend:
+//SEG9 main
+main: {
+  //SEG10 [4] *((const byte*) screen#0) ← (const byte) b#0 -- _deref_pbuc1=vbuc2 
+    lda #b
+    sta screen
+    jmp breturn
+  //SEG11 main::@return
+  breturn:
+  //SEG12 [5] return 
+    rts
+}
+
+ASSEMBLER OPTIMIZATIONS
+Removing instruction jmp b1
+Removing instruction jmp bend
+Removing instruction jmp breturn
+Succesful ASM optimization Pass5NextJumpElimination
+Removing instruction b1_from_bbegin:
+Removing instruction b1:
+Removing instruction bend_from_b1:
+Succesful ASM optimization Pass5RedundantLabelElimination
+Removing instruction bend:
+Removing instruction breturn:
+Succesful ASM optimization Pass5UnusedLabelElimination
+Updating BasicUpstart to call main directly
+Removing instruction jsr main
+Succesful ASM optimization Pass5SkipBegin
+Removing instruction bbegin:
+Succesful ASM optimization Pass5UnusedLabelElimination
+
+FINAL SYMBOL TABLE
+(label) @1
+(label) @begin
+(label) @end
+(byte) b
+(const byte) b#0 b = (byte) 'a'
+(void()) main()
+(label) main::@return
+(byte*) screen
+(const byte*) screen#0 screen = ((byte*))(word/signed word/dword/signed dword) 1024
+
+
+
+FINAL ASSEMBLER
+Score: 12
+
+//SEG0 File Comments
+// Illustrates the problem with variable forward references not working
+//SEG1 Basic Upstart
+.pc = $801 "Basic"
+:BasicUpstart(main)
+.pc = $80d "Program"
+//SEG2 Global Constants & labels
+  .label screen = $400
+  .const b = 'a'
+//SEG3 @begin
+//SEG4 [1] phi from @begin to @1 [phi:@begin->@1]
+//SEG5 @1
+//SEG6 [2] call main 
+//SEG7 [3] phi from @1 to @end [phi:@1->@end]
+//SEG8 @end
+//SEG9 main
+main: {
+  //SEG10 [4] *((const byte*) screen#0) ← (const byte) b#0 -- _deref_pbuc1=vbuc2 
+    lda #b
+    sta screen
+  //SEG11 main::@return
+  //SEG12 [5] return 
+    rts
+}
+

src/test/ref/var-forward-problem2.sym

@@ -0,0 +1,10 @@
+(label) @1
+(label) @begin
+(label) @end
+(byte) b
+(const byte) b#0 b = (byte) 'a'
+(void()) main()
+(label) main::@return
+(byte*) screen
+(const byte*) screen#0 screen = ((byte*))(word/signed word/dword/signed dword) 1024
+