Fixed up POKE and POKEW ,-syntax

Built with: go version go1.25.1 linux/amd64
Build date: 2026-06-11T00:16:51Z

SHA256 checksums:
f4fdc16cebdc1db0398ffd4599136fc767e431d319b44afdebd81845aeb4b8a8  c65gm_v1.5_darwin_amd64.tar.gz
eeb0f2afd1201bea068889ab14dc07fb9c01fa2dc452883e71efa71354cc3c77  c65gm_v1.5_darwin_arm64.tar.gz
fe1f597ca4a06b0470f4553b964c87cf10e4388cb831f7a4e52aa65fbc734e49  c65gm_v1.5_linux_amd64.tar.gz
971b630f0cec3eb01b3bdae3883d25d467ac1760a7632525a89566e23ce43c24  c65gm_v1.5_linux_arm64.tar.gz
d6314b4dab8ca297a0e57eabda581fba707f74c951c6c5f14ab8ea47d14cac2f  c65gm_v1.5_windows_amd64.zip

BUILDNUM

@@ -1 +1 @@
-5
+6

Dockerfile

@@ -1,5 +1,5 @@
-FROM ghcr.io/anomalyco/opencode:1.14.48
-#FROM ghcr.io/anomalyco/opencode:latest
+#FROM ghcr.io/anomalyco/opencode:1.14.48
+FROM ghcr.io/anomalyco/opencode:latest
 
 RUN apk add --no-cache go gcc musl-dev
 

examples/hires/hires.c65

@@ -8,12 +8,12 @@ FUNC sethires
   BYTE b
   b = PEEK $d011
   b = b | 32 //enable bitmap mode
-  POKE $d011 , b
+  POKE $d011, b
 
   b = PEEK $d018
   b = b & %11110000
   b = b | 8 //enable bitmap mode
-  POKE $d018 , b
+  POKE $d018, b
   
 
 FEND
@@ -22,7 +22,7 @@ FEND
 FUNC fillmem({WORD start_addr @ $fa} {WORD end_addr @ $fc} {BYTE value})
 
   WHILE start_addr <= end_addr
-    POKE start_addr , value
+    POKE start_addr, value
     start_addr++
   WEND
 

examples/load_binary_demo/cm.sh

@@ -0,0 +1,5 @@
+#!/bin/sh
+# Define filename as variable
+PROGNAME="load_binary_demo"
+# Compile and assemble directly
+c65gm ${PROGNAME}.c65

examples/load_binary_demo/load_binary_demo.c65

@@ -0,0 +1,50 @@
+//-----------------------------------------------------------
+// load_binary Demo
+// Demonstrates loading binary data from a file at compile time
+// using the Starlark scripting built-in load_binary().
+//
+// The SCRIPT block reads screendata.bin (40 bytes of C64
+// screen codes) and emits them as assembler data. At runtime,
+// a c65gm FOR loop copies the data to screen memory ($0400)
+// using WORD pointers with self-modifying code.
+//
+// Build: c65gm load_binary_demo.c65
+//-----------------------------------------------------------
+
+#INCLUDE <c64start.c65>
+
+GOTO start
+
+//-----------------------------------------------------------
+// Load binary data at compile time using Starlark load_binary()
+// and emit it as data statements in the assembly output.
+//-----------------------------------------------------------
+SCRIPT
+  data = load_binary("screendata.bin")
+  print("; Loaded %d bytes from screendata.bin" % len(data))
+  print("scrdata:")
+  for i in range(0, len(data), 8):
+      row = ", ".join(["%d" % b for b in data[i:i+8]])
+      print("  !8 " + row)
+ENDSCRIPT
+
+LABEL start
+
+  // Pointers to source data and screen memory
+  WORD src
+  WORD dst
+  BYTE i
+  BYTE val
+
+  POINTER src TO scrdata
+  POINTER dst TO $0400
+
+  // Copy 40 bytes from scrdata to screen memory
+  FOR i = 0 TO 39
+    val = PEEK src
+    POKE dst, val
+    src++
+    dst++
+  NEXT
+
+  SUBEND

examples/load_binary_demo/screendata.bin

@@ -0,0 +1,2 @@
+
	
+
 !"#$%&'(

examples/load_binary_demo/start_in_vice.sh

@@ -0,0 +1 @@
+x64 -autostartprgmode 1 load_binary_demo.prg

examples/memlib_demo/memlib_demo.c65

@@ -40,7 +40,7 @@ FUNC wait_key
   WEND
   
   // Reset key buffer
-  POKE $c6 WITH 0
+  POKE $c6, 0
   
 FEND
 

examples/memlib_demo2/memlib_demo2.c65

@@ -45,7 +45,7 @@ FUNC wait_key
     ENDIF
   WEND
 
-  POKE $c6 WITH 0
+  POKE $c6, 0
 FEND
 
 //-----------------------------------------------------------

examples/multdiv_demo/multdiv_demo.c65

@@ -36,7 +36,7 @@ FUNC wait_key
     ENDIF
   WEND
   
-  POKE $c6 WITH 0
+  POKE $c6, 0
 FEND
 
 //-----------------------------------------------------------

examples/multicolorbm/cm.sh

@@ -1,5 +1,5 @@
 #!/bin/sh
 # Define filename as variable
 PROGNAME="multicolorbm"
-# Compile and assemble directly
-c65gm ${PROGNAME}.c65
+# Compile and assemble directly, keep intermediate .asm file, enable optimizations
+c65gm build -i ${PROGNAME}.c65 --keep-asm --opt

examples/multicolorbm/multicolorbm.c65

@@ -8,16 +8,16 @@ FUNC setmulti
   BYTE b
   b = PEEK $d011
   b = b | 32
-  POKE $d011 , b
+  POKE $d011, b
 
   b = PEEK $d016
   b = b | 16
-  POKE $d016 , b
+  POKE $d016, b
 
   b = PEEK $d018
   b = b & %11110000
   b = b | 8
-  POKE $d018 , b
+  POKE $d018, b
 
 FEND
 
@@ -25,7 +25,7 @@ FEND
 FUNC fillmem({WORD start_addr @ $fa} {WORD end_addr @ $fc} {BYTE value})
 
   WHILE start_addr <= end_addr
-    POKE start_addr , value
+    POKE start_addr, value
     start_addr++
   WEND
 
@@ -41,7 +41,7 @@ FUNC main
   fillmem(screen, screen+999, $12)
   fillmem(colorram, colorram+999, $03)
   
-  POKE $d021 , 0
+  POKE $d021, 0
 
   WHILE 1
     fillmem($2000, $3fff, %00011011)

examples/multicolorbm_v2/cm.sh

@@ -0,0 +1,5 @@
+#!/bin/sh
+# Define filename as variable
+PROGNAME="multicolorbm_v2"
+# Compile and assemble directly, keep intermediate .asm file, enable optimizations
+c65gm build -i ${PROGNAME}.c65 --keep-asm --opt

examples/multicolorbm_v2/multicolorbm_v2.c65

@@ -0,0 +1,131 @@
+//-----------------------------------------------------------
+// multicolorbm_v2 - Multi-color bitmap demo using SCRIPT MACRO
+//
+// Uses compile-time code generation via SCRIPT MACRO to produce
+// optimized fill routines instead of a generic runtime loop.
+// The fill_fast macro analyzes the memory range at compile time
+// and selects the most cycle-efficient 6502 fill strategy.
+//-----------------------------------------------------------
+
+#INCLUDE <c64start.c65>
+#INCLUDE <c64defs.c65>
+
+GOTO start
+
+//-----------------------------------------------------------
+// SCRIPT LIBRARY: optimized fill code generation
+//
+// At compile time, this analyzes the start/end/value and emits
+// specialized assembly. Small fills (<256 bytes) use a simple
+// X-indexed loop. Whole-page fills use page-based unrolling.
+// Large partial-page fills choose the cycle-cheapest strategy.
+//-----------------------------------------------------------
+SCRIPT LIBRARY
+def to_hex(v):
+  digits = "0123456789abcdef"
+  return digits[(v >> 12) & 15] + digits[(v >> 8) & 15] + digits[(v >> 4) & 15] + digits[v & 15]
+
+def emit_fill_fast(start, end, value):
+  total = end - start + 1
+
+  print("")
+  print("; fill_fast $" + to_hex(start) + "..$" + to_hex(end) + " = " + str(total) + " bytes")
+  print("  lda #" + str(value))
+
+  if total < 256:
+    print("  ldx #" + str(total))
+    print("-")
+    print("  sta $" + to_hex(start) + "-1,x")
+    print("  dex")
+    print("  bne -")
+  elif total == 256:
+    print("  ldx #0")
+    print("-")
+    print("  sta $" + to_hex(start) + ",x")
+    print("  inx")
+    print("  bne -")
+  else:
+    full_pages = int(total / 256)
+    remain = total - full_pages * 256
+
+    cycles_a = (5 * full_pages + 4) * 256 + 9 * remain
+    cycles_b = (5 * (full_pages + 1) + 4) * 256 - 1
+
+    if cycles_a <= cycles_b:
+      pages = [start + i * 256 for i in range(full_pages)]
+      print("  ldx #0")
+      print("-")
+      for a in pages:
+        print("  sta $" + to_hex(a) + ",x")
+      print("  inx")
+      print("  bne -")
+      if remain > 0:
+        print("  ldx #" + str(remain))
+        print("--")
+        print("  sta $" + to_hex(start + full_pages * 256) + "-1,x")
+        print("  dex")
+        print("  bne --")
+    else:
+      pages = [start + i * 256 for i in range(full_pages)]
+      pages.append(end - 255)
+      print("  ldx #0")
+      print("-")
+      for a in pages:
+        print("  sta $" + to_hex(a) + ",x")
+      print("  inx")
+      print("  bne -")
+ENDSCRIPT
+
+//-----------------------------------------------------------
+// SCRIPT MACRO: inline fill_fast
+//
+// Replacements for runtime fillmem(). Generates optimized
+// assembly inline at each call site.
+//-----------------------------------------------------------
+SCRIPT MACRO fill_fast(start, end, value)
+  emit_fill_fast(start, end, value)
+ENDSCRIPT
+
+//-----------------------------------------------------------
+// VIC-II multi-color bitmap setup (unchanged from v1)
+//-----------------------------------------------------------
+FUNC setmulti
+  BYTE b
+  b = PEEK $d011
+  b = b | 32
+  POKE $d011, b
+
+  b = PEEK $d016
+  b = b | 16
+  POKE $d016, b
+
+  b = PEEK $d018
+  b = b & %11110000
+  b = b | 8
+  POKE $d018, b
+FEND
+
+//-----------------------------------------------------------
+// Main program
+//
+// Uses @fill_fast macro instead of runtime fillmem() loops.
+// Each invocation generates optimal fill code for its range.
+//-----------------------------------------------------------
+FUNC main
+  setmulti()
+
+  @fill_fast($0400, $0400+999, $12)
+  @fill_fast(colorram, colorram+999, $03)
+
+  POKE $d021, 0
+
+  WHILE 1
+    @fill_fast($2000, $3fff, %00011011)
+    @fill_fast($2000, $3fff, %01101100)
+    @fill_fast($2000, $3fff, %10110001)
+    @fill_fast($2000, $3fff, %11000110)
+  WEND
+FEND
+
+LABEL start
+main()

examples/multicolorbm_v2/start_in_vice.sh

@@ -0,0 +1 @@
+x64 -autostartprgmode 1 multicolorbm_v2.prg

examples/shift_demo/shift_demo.c65

@@ -43,7 +43,7 @@ FUNC wait_key
   WEND
   
   // Reset key buffer
-  POKE $c6 WITH 0
+  POKE $c6, 0
   
 FEND
 

internal/commands/and.go

@@ -156,6 +156,26 @@ func (c *AndCommand) Interpret(line preproc.Line, ctx *compiler.CompilerContext)
 		}
 	}
 
+	// Normalize operands: leverage AND commutativity to swap if needed
+	// This ensures word operands are in param1 when mixed with bytes
+	// Makes code generation simpler and more consistent
+	param1IsByteSized := false
+	if c.param1IsVar {
+		param1IsByteSized = (c.param1VarKind == compiler.KindByte)
+	} else {
+		param1IsByteSized = ((c.param1Value >> 8) & 0xFF) == 0
+	}
+
+	param2IsWord := c.param2IsVar && c.param2VarKind == compiler.KindWord
+
+	if param1IsByteSized && param2IsWord {
+		// Swap param1 and param2
+		c.param1VarName, c.param2VarName = c.param2VarName, c.param1VarName
+		c.param1VarKind, c.param2VarKind = c.param2VarKind, c.param1VarKind
+		c.param1Value, c.param2Value = c.param2Value, c.param1Value
+		c.param1IsVar, c.param2IsVar = c.param2IsVar, c.param1IsVar
+	}
+
 	return nil
 }
 
@@ -180,6 +200,46 @@ func (c *AndCommand) Generate(_ *compiler.CompilerContext) ([]string, error) {
 	}
 
 	// At least one param is a variable - generate AND code
+
+	// Same variable on both sides: a & a = a
+	if c.param1IsVar && c.param2IsVar && c.param1VarName == c.param2VarName {
+		if c.destVarName == c.param1VarName {
+			return asm, nil
+		}
+		if c.param1VarKind == compiler.KindWord {
+			asm = append(asm, fmt.Sprintf("\tlda %s", c.param1VarName))
+			asm = append(asm, fmt.Sprintf("\tsta %s", c.destVarName))
+			asm = append(asm, fmt.Sprintf("\tlda %s+1", c.param1VarName))
+			asm = append(asm, fmt.Sprintf("\tsta %s+1", c.destVarName))
+		} else {
+			asm = append(asm, fmt.Sprintf("\tlda %s", c.param1VarName))
+			asm = append(asm, fmt.Sprintf("\tsta %s", c.destVarName))
+			if c.destVarKind == compiler.KindWord {
+				asm = append(asm, "\tlda #0")
+				asm = append(asm, fmt.Sprintf("\tsta %s+1", c.destVarName))
+			}
+		}
+		return asm, nil
+	}
+
+	// Track if A is known to be 0 after low byte (avoids redundant lda #0 for high byte)
+	aIsZero := false
+
+	// If either param is literal 0, low byte result is always 0
+	param1LoIsZero := !c.param1IsVar && uint8(c.param1Value&0xFF) == 0
+	param2LoIsZero := !c.param2IsVar && uint8(c.param2Value&0xFF) == 0
+
+	// If param1 is literal $FF and param2 is a var, just load param2 ($FF AND a = a)
+	param1IsFF := !c.param1IsVar && uint8(c.param1Value&0xFF) == 0xFF
+
+	if param1LoIsZero || param2LoIsZero {
+		asm = append(asm, "\tlda #0")
+		asm = append(asm, fmt.Sprintf("\tsta %s", c.destVarName))
+		aIsZero = true
+	} else if param1IsFF && c.param2IsVar {
+		asm = append(asm, fmt.Sprintf("\tlda %s", c.param2VarName))
+		asm = append(asm, fmt.Sprintf("\tsta %s", c.destVarName))
+	} else {
 		// Load param1
 		if c.param1IsVar {
 			asm = append(asm, fmt.Sprintf("\tlda %s", c.param1VarName))
@@ -187,18 +247,36 @@ func (c *AndCommand) Generate(_ *compiler.CompilerContext) ([]string, error) {
 			asm = append(asm, fmt.Sprintf("\tlda #$%02x", uint8(c.param1Value&0xFF)))
 		}
 
-	// AND with param2
+		// AND with param2 (skip if literal $FF, as and #$ff preserves accumulator)
 		if c.param2IsVar {
 			asm = append(asm, fmt.Sprintf("\tand %s", c.param2VarName))
-	} else {
+		} else if uint8(c.param2Value&0xFF) != 0xFF {
 			asm = append(asm, fmt.Sprintf("\tand #$%02x", uint8(c.param2Value&0xFF)))
 		}
 
 		// Store low byte
 		asm = append(asm, fmt.Sprintf("\tsta %s", c.destVarName))
+	}
 
 	// If destination is word, handle high byte
 	if c.destVarKind == compiler.KindWord {
+		// Determine if param2 high byte is effectively 0
+		// (AND with 0 always yields 0 regardless of param1 high byte)
+		param2HiEffectiveZero := false
+		if c.param2IsVar {
+			if c.param2VarKind == compiler.KindByte {
+				param2HiEffectiveZero = true
+			}
+		} else {
+			param2HiEffectiveZero = ((c.param2Value >> 8) & 0xFF) == 0
+		}
+
+		if param2HiEffectiveZero {
+			if !aIsZero {
+				asm = append(asm, "\tlda #0")
+			}
+			asm = append(asm, fmt.Sprintf("\tsta %s+1", c.destVarName))
+		} else {
 			// Load high byte of param1
 			if c.param1IsVar {
 				if c.param1VarKind == compiler.KindWord {
@@ -216,7 +294,7 @@ func (c *AndCommand) Generate(_ *compiler.CompilerContext) ([]string, error) {
 				if c.param2VarKind == compiler.KindWord {
 					asm = append(asm, fmt.Sprintf("\tand %s+1", c.param2VarName))
 				} else {
-				asm = append(asm, "\tand #0")
+					asm = append(asm, fmt.Sprintf("\tand #$%02x", uint8(c.param2Value&0xFF)))
 				}
 			} else {
 				hi := uint8((c.param2Value >> 8) & 0xFF)
@@ -226,6 +304,7 @@ func (c *AndCommand) Generate(_ *compiler.CompilerContext) ([]string, error) {
 			// Store high byte
 			asm = append(asm, fmt.Sprintf("\tsta %s+1", c.destVarName))
 		}
+	}
 
 	return asm, nil
 }

internal/commands/and_test.go

@@ -71,7 +71,6 @@ func TestAndCommand_OldSyntax(t *testing.T) {
 				"\tand b",
 				"\tsta result",
 				"\tlda #0",
-				"\tand #0",
 				"\tsta result+1",
 			},
 		},
@@ -113,8 +112,7 @@ func TestAndCommand_OldSyntax(t *testing.T) {
 				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
 			},
 			wantAsm: []string{
-				"\tlda #$ff",
-				"\tand b",
+				"\tlda b",
 				"\tsta result",
 			},
 		},
@@ -182,8 +180,7 @@ func TestAndCommand_OldSyntax(t *testing.T) {
 				"\tlda wval",
 				"\tand bval",
 				"\tsta result",
-				"\tlda wval+1",
-				"\tand #0",
+				"\tlda #0",
 				"\tsta result+1",
 			},
 		},
@@ -286,7 +283,6 @@ func TestAndCommand_NewSyntax(t *testing.T) {
 				"\tand b",
 				"\tsta result",
 				"\tlda #0",
-				"\tand #0",
 				"\tsta result+1",
 			},
 		},
@@ -320,6 +316,96 @@ func TestAndCommand_NewSyntax(t *testing.T) {
 				"\tsta result",
 			},
 		},
+		{
+			name: "byte & $FF -> byte (optimization: skip and #$ff)",
+			line: "result = a & $FF",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xAB, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda a",
+				"\tsta result",
+			},
+		},
+		{
+			name: "byte & $FF -> word (optimization: skip and #$ff)",
+			line: "result = a & $FF",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xAB, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda a",
+				"\tsta result",
+				"\tlda #0",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "byte & 0 -> byte (optimization: lda #0)",
+			line: "result = a & 0",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xAB, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #0",
+				"\tsta result",
+			},
+		},
+		{
+			name: "0 & byte -> byte (optimization: lda #0)",
+			line: "result = 0 & a",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xAB, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #0",
+				"\tsta result",
+			},
+		},
+		{
+			name: "byte & 0 -> word (optimization: lda #0)",
+			line: "result = a & 0",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xAB, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #0",
+				"\tsta result",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "byte & $100 -> byte (optimization: lda #0, low byte of $100 is 0)",
+			line: "result = a & $100",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xAB, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #0",
+				"\tsta result",
+			},
+		},
+		{
+			name: "byte & $100 -> word (optimization: lda #0)",
+			line: "result = a & $100",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xAB, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #0",
+				"\tsta result",
+				"\tlda #0",
+				"\tand #$01",
+				"\tsta result+1",
+			},
+		},
 		{
 			name: "constant folding",
 			line: "result = 255 & 15",
@@ -358,6 +444,206 @@ func TestAndCommand_NewSyntax(t *testing.T) {
 				"\tsta result",
 			},
 		},
+		{
+			name: "byte & byte -> byte (same variable: a & a = a)",
+			line: "result = a & a",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xAB, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda a",
+				"\tsta result",
+			},
+		},
+		{
+			name: "word & word -> word (same variable: x & x = x)",
+			line: "result = x & x",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("x", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda x",
+				"\tsta result",
+				"\tlda x+1",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "$FF & byte -> word (optimization: lda param2)",
+			line: "result = $FF & a",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xAB, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda a",
+				"\tsta result",
+				"\tlda #0",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "byte & word -> byte (swap case)",
+			line: "result = bval & wval",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("bval", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda wval",
+				"\tand bval",
+				"\tsta result",
+			},
+		},
+		{
+			name: "byte & word -> word (swap case)",
+			line: "result = bval & wval",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("bval", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda wval",
+				"\tand bval",
+				"\tsta result",
+				"\tlda #0",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "word_const & byte -> byte",
+			line: "result = 300 & b",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("b", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #$2c",
+				"\tand b",
+				"\tsta result",
+			},
+		},
+		{
+			name: "word_const & byte -> word",
+			line: "result = 300 & b",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("b", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #$2c",
+				"\tand b",
+				"\tsta result",
+				"\tlda #0",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "byte & word_const -> byte",
+			line: "result = b & 300",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("b", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda b",
+				"\tand #$2c",
+				"\tsta result",
+			},
+		},
+		{
+			name: "byte & word_const -> word",
+			line: "result = b & 300",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("b", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda b",
+				"\tand #$2c",
+				"\tsta result",
+				"\tlda #0",
+				"\tand #$01",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "0 & byte -> word (optimization: lda #0, skip high byte)",
+			line: "result = 0 & a",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xAB, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #0",
+				"\tsta result",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "self-assignment: word &= byte",
+			line: "wval = wval & bval",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("bval", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda wval",
+				"\tand bval",
+				"\tsta wval",
+				"\tlda #0",
+				"\tsta wval+1",
+			},
+		},
+		{
+			name: "self-assignment: word &= byte_const",
+			line: "wval = wval & 42",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda wval",
+				"\tand #$2a",
+				"\tsta wval",
+				"\tlda #0",
+				"\tsta wval+1",
+			},
+		},
+		{
+			name: "self-assignment: word &= word_const",
+			line: "wval = wval & 300",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda wval",
+				"\tand #$2c",
+				"\tsta wval",
+				"\tlda wval+1",
+				"\tand #$01",
+				"\tsta wval+1",
+			},
+		},
+		{
+			name: "self-assignment: word &= word",
+			line: "wval = wval & wval2",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("wval2", "", compiler.KindWord, 0x5678, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda wval",
+				"\tand wval2",
+				"\tsta wval",
+				"\tlda wval+1",
+				"\tand wval2+1",
+				"\tsta wval+1",
+			},
+		},
 		{
 			name: "error: unknown destination",
 			line: "unknown = a & b",

internal/commands/macro.go

@@ -13,6 +13,7 @@ import (
 type MacroCommand struct {
 	macroName      string
 	args           []string
+	pragmaSetIndex int
 }
 
 func (c *MacroCommand) WillHandle(line preproc.Line) bool {
@@ -30,11 +31,12 @@ func (c *MacroCommand) Interpret(line preproc.Line, _ *compiler.CompilerContext)
 
 	c.macroName = name
 	c.args = args
+	c.pragmaSetIndex = line.PragmaSetIndex
 	return nil
 }
 
 func (c *MacroCommand) Generate(ctx *compiler.CompilerContext) ([]string, error) {
-	macroOutput, err := compiler.ExecuteMacro(c.macroName, c.args, ctx)
+	macroOutput, err := compiler.ExecuteMacro(c.macroName, c.args, ctx, c.pragmaSetIndex)
 	if err != nil {
 		return nil, fmt.Errorf("macro %s: %w", c.macroName, err)
 	}

internal/commands/or.go

@@ -156,6 +156,26 @@ func (c *OrCommand) Interpret(line preproc.Line, ctx *compiler.CompilerContext)
 		}
 	}
 
+	// Normalize operands: leverage OR commutativity to swap if needed
+	// This ensures word operands are in param1 when mixed with bytes
+	// Makes code generation simpler and more consistent
+	param1IsByteSized := false
+	if c.param1IsVar {
+		param1IsByteSized = (c.param1VarKind == compiler.KindByte)
+	} else {
+		param1IsByteSized = ((c.param1Value >> 8) & 0xFF) == 0
+	}
+
+	param2IsWord := c.param2IsVar && c.param2VarKind == compiler.KindWord
+
+	if param1IsByteSized && param2IsWord {
+		// Swap param1 and param2
+		c.param1VarName, c.param2VarName = c.param2VarName, c.param1VarName
+		c.param1VarKind, c.param2VarKind = c.param2VarKind, c.param1VarKind
+		c.param1Value, c.param2Value = c.param2Value, c.param1Value
+		c.param1IsVar, c.param2IsVar = c.param2IsVar, c.param1IsVar
+	}
+
 	return nil
 }
 
@@ -180,6 +200,39 @@ func (c *OrCommand) Generate(_ *compiler.CompilerContext) ([]string, error) {
 	}
 
 	// At least one param is a variable - generate OR code
+
+	// Same variable on both sides: a | a = a
+	if c.param1IsVar && c.param2IsVar && c.param1VarName == c.param2VarName {
+		if c.destVarName == c.param1VarName {
+			return asm, nil
+		}
+		if c.param1VarKind == compiler.KindWord {
+			asm = append(asm, fmt.Sprintf("\tlda %s", c.param1VarName))
+			asm = append(asm, fmt.Sprintf("\tsta %s", c.destVarName))
+			asm = append(asm, fmt.Sprintf("\tlda %s+1", c.param1VarName))
+			asm = append(asm, fmt.Sprintf("\tsta %s+1", c.destVarName))
+		} else {
+			asm = append(asm, fmt.Sprintf("\tlda %s", c.param1VarName))
+			asm = append(asm, fmt.Sprintf("\tsta %s", c.destVarName))
+			if c.destVarKind == compiler.KindWord {
+				asm = append(asm, "\tlda #0")
+				asm = append(asm, fmt.Sprintf("\tsta %s+1", c.destVarName))
+			}
+		}
+		return asm, nil
+	}
+
+	// If either param is literal $FF, low byte result is always $FF
+	param1IsFF := !c.param1IsVar && uint8(c.param1Value&0xFF) == 0xFF
+	param2IsFF := !c.param2IsVar && uint8(c.param2Value&0xFF) == 0xFF
+
+	if param1IsFF || param2IsFF {
+		asm = append(asm, "\tlda #$ff")
+		asm = append(asm, fmt.Sprintf("\tsta %s", c.destVarName))
+	} else if !c.param1IsVar && uint8(c.param1Value&0xFF) == 0 && c.param2IsVar {
+		asm = append(asm, fmt.Sprintf("\tlda %s", c.param2VarName))
+		asm = append(asm, fmt.Sprintf("\tsta %s", c.destVarName))
+	} else {
 		// Load param1
 		if c.param1IsVar {
 			asm = append(asm, fmt.Sprintf("\tlda %s", c.param1VarName))
@@ -187,18 +240,33 @@ func (c *OrCommand) Generate(_ *compiler.CompilerContext) ([]string, error) {
 			asm = append(asm, fmt.Sprintf("\tlda #$%02x", uint8(c.param1Value&0xFF)))
 		}
 
-	// OR with param2
+		// OR with param2 (skip if literal 0, as ora #0 is a no-op)
 		if c.param2IsVar {
 			asm = append(asm, fmt.Sprintf("\tora %s", c.param2VarName))
-	} else {
+		} else if uint8(c.param2Value&0xFF) != 0 {
 			asm = append(asm, fmt.Sprintf("\tora #$%02x", uint8(c.param2Value&0xFF)))
 		}
 
 		// Store low byte
 		asm = append(asm, fmt.Sprintf("\tsta %s", c.destVarName))
+	}
 
 	// If destination is word, handle high byte
 	if c.destVarKind == compiler.KindWord {
+		// Optimization: skip high byte for self-assignment when param2 is byte-sized
+		// e.g., word_var = word_var | byte_var would just copy high byte to itself
+		if c.destVarName == c.param1VarName {
+			param2IsByteSized := false
+			if c.param2IsVar {
+				param2IsByteSized = (c.param2VarKind == compiler.KindByte)
+			} else {
+				param2IsByteSized = ((c.param2Value >> 8) & 0xFF) == 0
+			}
+			if param2IsByteSized {
+				return asm, nil
+			}
+		}
+
 		// Load high byte of param1
 		if c.param1IsVar {
 			if c.param1VarKind == compiler.KindWord {
@@ -211,17 +279,19 @@ func (c *OrCommand) Generate(_ *compiler.CompilerContext) ([]string, error) {
 			asm = append(asm, fmt.Sprintf("\tlda #$%02x", hi))
 		}
 
-		// OR with high byte of param2
+		// OR with high byte of param2 (skip if literal 0, as ora #0 is a no-op)
 		if c.param2IsVar {
 			if c.param2VarKind == compiler.KindWord {
 				asm = append(asm, fmt.Sprintf("\tora %s+1", c.param2VarName))
-			} else {
-				asm = append(asm, "\tora #0")
 			}
+			// Skip ora when param2 is byte var (high byte is 0)
 		} else {
 			hi := uint8((c.param2Value >> 8) & 0xFF)
+			if hi != 0 {
 				asm = append(asm, fmt.Sprintf("\tora #$%02x", hi))
 			}
+			// Skip ora when param2 const high byte is 0
+		}
 
 		// Store high byte
 		asm = append(asm, fmt.Sprintf("\tsta %s+1", c.destVarName))

internal/commands/or_test.go

@@ -71,7 +71,6 @@ func TestOrCommand_OldSyntax(t *testing.T) {
 				"\tora b",
 				"\tsta result",
 				"\tlda #0",
-				"\tora #0",
 				"\tsta result+1",
 			},
 		},
@@ -183,7 +182,6 @@ func TestOrCommand_OldSyntax(t *testing.T) {
 				"\tora bval",
 				"\tsta result",
 				"\tlda wval+1",
-				"\tora #0",
 				"\tsta result+1",
 			},
 		},
@@ -286,7 +284,6 @@ func TestOrCommand_NewSyntax(t *testing.T) {
 				"\tora b",
 				"\tsta result",
 				"\tlda #0",
-				"\tora #0",
 				"\tsta result+1",
 			},
 		},
@@ -320,6 +317,32 @@ func TestOrCommand_NewSyntax(t *testing.T) {
 				"\tsta result",
 			},
 		},
+		{
+			name: "byte | 0 -> byte (optimization: skip ora #0)",
+			line: "result = a | 0",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xF0, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda a",
+				"\tsta result",
+			},
+		},
+		{
+			name: "byte | 0 -> word (optimization: skip ora #0)",
+			line: "result = a | 0",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xF0, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda a",
+				"\tsta result",
+				"\tlda #0",
+				"\tsta result+1",
+			},
+		},
 		{
 			name: "constant folding",
 			line: "result = 15 | 240",
@@ -358,6 +381,294 @@ func TestOrCommand_NewSyntax(t *testing.T) {
 				"\tsta result",
 			},
 		},
+		{
+			name: "byte | $FF -> byte (optimization: lda #$ff)",
+			line: "result = a | $FF",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xF0, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #$ff",
+				"\tsta result",
+			},
+		},
+		{
+			name: "$FF | byte -> byte (optimization: lda #$ff)",
+			line: "result = $FF | a",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xF0, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #$ff",
+				"\tsta result",
+			},
+		},
+		{
+			name: "byte | $FF -> word (optimization: lda #$ff)",
+			line: "result = a | $FF",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xF0, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #$ff",
+				"\tsta result",
+				"\tlda #0",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "byte | byte -> byte (same variable: a | a = a)",
+			line: "result = a | a",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xF0, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda a",
+				"\tsta result",
+			},
+		},
+		{
+			name: "0 | byte -> word (optimization: skip ora #0)",
+			line: "result = 0 | a",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xF0, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda a",
+				"\tsta result",
+				"\tlda #$00",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "byte | word -> byte (swap case)",
+			line: "result = bval | wval",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("bval", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda wval",
+				"\tora bval",
+				"\tsta result",
+			},
+		},
+		{
+			name: "byte | word -> word (swap case)",
+			line: "result = bval | wval",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("bval", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda wval",
+				"\tora bval",
+				"\tsta result",
+				"\tlda wval+1",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "$FF | word -> word",
+			line: "result = $FF | wval",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #$ff",
+				"\tsta result",
+				"\tlda wval+1",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "word | $FF -> word",
+			line: "result = wval | $FF",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #$ff",
+				"\tsta result",
+				"\tlda wval+1",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "$FF00 | byte -> byte",
+			line: "result = $FF00 | b",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("b", "", compiler.KindByte, 0xAB, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda b",
+				"\tsta result",
+			},
+		},
+		{
+			name: "$FF00 | byte -> word",
+			line: "result = $FF00 | b",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("b", "", compiler.KindByte, 0xAB, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda b",
+				"\tsta result",
+				"\tlda #$ff",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "byte | word_const -> byte",
+			line: "result = b | 300",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("b", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda b",
+				"\tora #$2c",
+				"\tsta result",
+			},
+		},
+		{
+			name: "byte | word_const -> word",
+			line: "result = b | 300",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("b", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda b",
+				"\tora #$2c",
+				"\tsta result",
+				"\tlda #0",
+				"\tora #$01",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "word_const | byte -> byte",
+			line: "result = 300 | b",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("b", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #$2c",
+				"\tora b",
+				"\tsta result",
+			},
+		},
+		{
+			name: "word_const | byte -> word",
+			line: "result = 300 | b",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("b", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #$2c",
+				"\tora b",
+				"\tsta result",
+				"\tlda #$01",
+				"\tsta result+1",
+			},
+		},
+		{
+			name: "self-assignment: word |= byte (optimization: skip high byte entirely)",
+			line: "wval = wval | bval",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("bval", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda wval",
+				"\tora bval",
+				"\tsta wval",
+			},
+		},
+		{
+			name: "self-assignment reversed: word |= byte (optimization via swap)",
+			line: "wval = bval | wval",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("bval", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda wval",
+				"\tora bval",
+				"\tsta wval",
+			},
+		},
+		{
+			name: "self-assignment: word |= byte_const (optimization: skip high byte entirely)",
+			line: "wval = wval | 42",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda wval",
+				"\tora #$2a",
+				"\tsta wval",
+			},
+		},
+		{
+			name: "self-assignment: word |= word_const (no optimization: high byte needed)",
+			line: "wval = wval | 300",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda wval",
+				"\tora #$2c",
+				"\tsta wval",
+				"\tlda wval+1",
+				"\tora #$01",
+				"\tsta wval+1",
+			},
+		},
+		{
+			name: "self-assignment: word |= word (no optimization: both high bytes needed)",
+			line: "wval = wval | wval2",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("wval", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("wval2", "", compiler.KindWord, 0x5678, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda wval",
+				"\tora wval2",
+				"\tsta wval",
+				"\tlda wval+1",
+				"\tora wval2+1",
+				"\tsta wval+1",
+			},
+		},
+		{
+			name: "word | word -> word (same variable: x | x = x)",
+			line: "result = x | x",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("x", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda x",
+				"\tsta result",
+				"\tlda x+1",
+				"\tsta result+1",
+			},
+		},
 		{
 			name: "error: unknown destination",
 			line: "unknown = a | b",

internal/commands/poke.go

@@ -38,7 +38,7 @@ type PokeCommand struct {
 }
 
 func (c *PokeCommand) WillHandle(line preproc.Line) bool {
-	params, err := utils.ParseParams(line.Text)
+	params, err := utils.ParseParams(utils.NormalizeCommas(line.Text))
 	if err != nil || len(params) != 4 {
 		return false
 	}
@@ -62,7 +62,7 @@ func (c *PokeCommand) Interpret(line preproc.Line, ctx *compiler.CompilerContext
 	// Store pragma set for Generate phase
 	c.pragmaSet = ctx.Pragma.GetPragmaSetByIndex(line.PragmaSetIndex)
 
-	params, err := utils.ParseParams(line.Text)
+	params, err := utils.ParseParams(utils.NormalizeCommas(line.Text))
 	if err != nil {
 		return err
 	}

internal/commands/poke_test.go

@@ -0,0 +1,987 @@
+package commands
+
+import (
+	"strings"
+	"testing"
+
+	"c65gm/internal/compiler"
+	"c65gm/internal/preproc"
+)
+
+// setupPokeVars adds all needed symbols to a symbol table for POKE/POKEW tests.
+func setupPokeVars(st *compiler.SymbolTable) {
+	st.AddConst("vic2", "", compiler.KindWord, 0xd000, preproc.Line{Filename: "test.c65", LineNo: 1})
+	st.AddVar("addrvar", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 2})
+	st.AddVar("valvar", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 3})
+	st.AddVar("wvalvar", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 4})
+	st.AddVar("waddrvar", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 5})
+	st.AddAbsolute("zpptr", "", compiler.KindWord, 0x80, preproc.Line{Filename: "test.c65", LineNo: 6})
+	st.AddVar("offsvar", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 7})
+	st.AddAbsolute("byaddr", "", compiler.KindByte, 0x40, preproc.Line{Filename: "test.c65", LineNo: 8})
+}
+
+func newCtx() *compiler.CompilerContext {
+	pragma := preproc.NewPragma()
+	ctx := compiler.NewCompilerContext(pragma)
+	setupPokeVars(ctx.SymbolTable)
+	return ctx
+}
+
+func newLine(text string, pragma *preproc.Pragma) preproc.Line {
+	return preproc.Line{
+		Text:           text,
+		Kind:           preproc.Source,
+		PragmaSetIndex: pragma.GetCurrentPragmaSetIndex(),
+	}
+}
+
+// =============================================================================
+// POKE comma-spacing tests (constant address + literal value — Case 4)
+// =============================================================================
+
+func TestPokeCommaSpacing(t *testing.T) {
+	expectedAsm := []string{
+		"\tlda #5",
+		"\tsta 53280",
+	}
+
+	tests := []struct {
+		name string
+		line string
+	}{
+		{"space before and after comma", "POKE $d020 , 5"},
+		{"no space before or after comma", "POKE $d020,5"},
+		{"no space before comma, space after", "POKE $d020, 5"},
+		{"space before comma, no space after", "POKE $d020 ,5"},
+		{"no space comma, expression address", "POKE $d020+0, 5"},
+		{"WITH keyword", "POKE $d020 WITH 5"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := newCtx()
+			cmd := &PokeCommand{}
+			line := newLine(tt.line, ctx.Pragma)
+
+			if err := cmd.Interpret(line, ctx); err != nil {
+				t.Fatalf("Interpret() error = %v", err)
+			}
+			asm, err := cmd.Generate(ctx)
+			if err != nil {
+				t.Fatalf("Generate() error = %v", err)
+			}
+			if !equalAsm(asm, expectedAsm) {
+				t.Errorf("Generate() mismatch\ngot:\n%s\nwant:\n%s",
+					strings.Join(asm, "\n"),
+					strings.Join(expectedAsm, "\n"))
+			}
+		})
+	}
+}
+
+// =============================================================================
+// POKEW comma-spacing tests (constant address + literal value — Case 4)
+// =============================================================================
+
+func TestPokeWCommaSpacing(t *testing.T) {
+	expectedAsm := []string{
+		"\tlda #$65",
+		"\tsta 53280",
+		"\tlda #$00",
+		"\tsta 53281",
+	}
+
+	tests := []struct {
+		name string
+		line string
+	}{
+		{"space before and after comma", "POKEW $d020 , 101"},
+		{"no space before or after comma", "POKEW $d020,101"},
+		{"no space before comma, space after", "POKEW $d020, 101"},
+		{"space before comma, no space after", "POKEW $d020 ,101"},
+		{"WITH keyword", "POKEW $d020 WITH 101"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := newCtx()
+			cmd := &PokeWCommand{}
+			line := newLine(tt.line, ctx.Pragma)
+
+			if err := cmd.Interpret(line, ctx); err != nil {
+				t.Fatalf("Interpret() error = %v", err)
+			}
+			asm, err := cmd.Generate(ctx)
+			if err != nil {
+				t.Fatalf("Generate() error = %v", err)
+			}
+			if !equalAsm(asm, expectedAsm) {
+				t.Errorf("Generate() mismatch\ngot:\n%s\nwant:\n%s",
+					strings.Join(asm, "\n"),
+					strings.Join(expectedAsm, "\n"))
+			}
+		})
+	}
+}
+
+// =============================================================================
+// POKE Case 4 — Direct addressing (expression/constant address)
+// =============================================================================
+
+func TestPokeDirectAddr(t *testing.T) {
+	tests := []struct {
+		name    string
+		line    string
+		wantAsm []string
+	}{
+		{
+			name: "expression constant + expression value, no-space comma",
+			line: "POKE vic2+15,5+2",
+			wantAsm: []string{
+				"\tlda #7",
+				"\tsta 53263",
+			},
+		},
+		{
+			name: "variable value, no-space comma",
+			line: "POKE $d020,valvar",
+			wantAsm: []string{
+				"\tlda valvar",
+				"\tsta 53280",
+			},
+		},
+		{
+			name: "variable value, space before comma",
+			line: "POKE $d020 ,valvar",
+			wantAsm: []string{
+				"\tlda valvar",
+				"\tsta 53280",
+			},
+		},
+		{
+			name: "variable value, space after comma",
+			line: "POKE $d020, valvar",
+			wantAsm: []string{
+				"\tlda valvar",
+				"\tsta 53280",
+			},
+		},
+		{
+			name: "expression address + var value, no-space comma",
+			line: "POKE vic2+15,valvar",
+			wantAsm: []string{
+				"\tlda valvar",
+				"\tsta 53263",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := newCtx()
+			cmd := &PokeCommand{}
+			line := newLine(tt.line, ctx.Pragma)
+
+			if err := cmd.Interpret(line, ctx); err != nil {
+				t.Fatalf("Interpret() error = %v", err)
+			}
+			asm, err := cmd.Generate(ctx)
+			if err != nil {
+				t.Fatalf("Generate() error = %v", err)
+			}
+			if !equalAsm(asm, tt.wantAsm) {
+				t.Errorf("Generate() mismatch\ngot:\n%s\nwant:\n%s",
+					strings.Join(asm, "\n"),
+					strings.Join(tt.wantAsm, "\n"))
+			}
+		})
+	}
+}
+
+// =============================================================================
+// POKE Case 1 — ZP pointer (indexed indirect addressing)
+// =============================================================================
+
+func TestPokeZPPointer(t *testing.T) {
+	tests := []struct {
+		name    string
+		line    string
+		wantAsm []string
+	}{
+		{
+			name: "no offset, literal value, no-space comma",
+			line: "POKE zpptr,10",
+			wantAsm: []string{
+				"\tldy #0",
+				"\tlda #10",
+				"\tsta (zpptr),y",
+			},
+		},
+		{
+			name: "no offset, var value, no-space comma",
+			line: "POKE zpptr,valvar",
+			wantAsm: []string{
+				"\tldy #0",
+				"\tlda valvar",
+				"\tsta (zpptr),y",
+			},
+		},
+		{
+			name: "literal offset, literal value, no-space comma",
+			line: "POKE zpptr[5],10",
+			wantAsm: []string{
+				"\tldy #5",
+				"\tlda #10",
+				"\tsta (zpptr),y",
+			},
+		},
+		{
+			name: "literal offset, var value, no-space comma",
+			line: "POKE zpptr[5],valvar",
+			wantAsm: []string{
+				"\tldy #5",
+				"\tlda valvar",
+				"\tsta (zpptr),y",
+			},
+		},
+		{
+			name: "var offset, literal value, no-space comma",
+			line: "POKE zpptr[offsvar],10",
+			wantAsm: []string{
+				"\tldy offsvar",
+				"\tlda #10",
+				"\tsta (zpptr),y",
+			},
+		},
+		{
+			name: "var offset, var value, no-space comma",
+			line: "POKE zpptr[offsvar],valvar",
+			wantAsm: []string{
+				"\tldy offsvar",
+				"\tlda valvar",
+				"\tsta (zpptr),y",
+			},
+		},
+		{
+			name: "literal offset, var value, spaced comma",
+			line: "POKE zpptr[5] , valvar",
+			wantAsm: []string{
+				"\tldy #5",
+				"\tlda valvar",
+				"\tsta (zpptr),y",
+			},
+		},
+		{
+			name: "word variable value (uses low byte), no-space comma",
+			line: "POKE zpptr[5],wvalvar",
+			wantAsm: []string{
+				"\tldy #5",
+				"\tlda wvalvar",
+				"\tsta (zpptr),y",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := newCtx()
+			cmd := &PokeCommand{}
+			line := newLine(tt.line, ctx.Pragma)
+
+			if err := cmd.Interpret(line, ctx); err != nil {
+				t.Fatalf("Interpret() error = %v", err)
+			}
+			asm, err := cmd.Generate(ctx)
+			if err != nil {
+				t.Fatalf("Generate() error = %v", err)
+			}
+			if !equalAsm(asm, tt.wantAsm) {
+				t.Errorf("Generate() mismatch\ngot:\n%s\nwant:\n%s",
+					strings.Join(asm, "\n"),
+					strings.Join(tt.wantAsm, "\n"))
+			}
+		})
+	}
+}
+
+// =============================================================================
+// POKE Case 2 — Byte variable address (self-modifying code)
+// =============================================================================
+
+func TestPokeSMByteAddr(t *testing.T) {
+	tests := []struct {
+		name    string
+		line    string
+		wantAsm []string
+	}{
+		{
+			name: "literal value, no-space comma",
+			line: "POKE addrvar,10",
+			wantAsm: []string{
+				"\tlda addrvar",
+				"\tsta _L1+1",
+				"\tlda #10",
+				"_L1",
+				"\tsta $ff",
+			},
+		},
+		{
+			name: "var value, no-space comma",
+			line: "POKE addrvar,valvar",
+			wantAsm: []string{
+				"\tlda addrvar",
+				"\tsta _L1+1",
+				"\tlda valvar",
+				"_L1",
+				"\tsta $ff",
+			},
+		},
+		{
+			name: "word var value (uses low byte), no-space comma",
+			line: "POKE addrvar,wvalvar",
+			wantAsm: []string{
+				"\tlda addrvar",
+				"\tsta _L1+1",
+				"\tlda wvalvar",
+				"_L1",
+				"\tsta $ff",
+			},
+		},
+		{
+			name: "literal value, spaced comma",
+			line: "POKE addrvar , 10",
+			wantAsm: []string{
+				"\tlda addrvar",
+				"\tsta _L1+1",
+				"\tlda #10",
+				"_L1",
+				"\tsta $ff",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := newCtx()
+			cmd := &PokeCommand{}
+			line := newLine(tt.line, ctx.Pragma)
+
+			if err := cmd.Interpret(line, ctx); err != nil {
+				t.Fatalf("Interpret() error = %v", err)
+			}
+			asm, err := cmd.Generate(ctx)
+			if err != nil {
+				t.Fatalf("Generate() error = %v", err)
+			}
+			if !equalAsm(asm, tt.wantAsm) {
+				t.Errorf("Generate() mismatch\ngot:\n%s\nwant:\n%s",
+					strings.Join(asm, "\n"),
+					strings.Join(tt.wantAsm, "\n"))
+			}
+		})
+	}
+}
+
+// =============================================================================
+// POKE Case 3 — Word variable address (self-modifying code)
+// =============================================================================
+
+func TestPokeSMWordAddr(t *testing.T) {
+	tests := []struct {
+		name    string
+		line    string
+		wantAsm []string
+	}{
+		{
+			name: "literal value, no-space comma",
+			line: "POKE waddrvar,10",
+			wantAsm: []string{
+				"\tlda waddrvar",
+				"\tsta _L1+1",
+				"\tlda waddrvar+1",
+				"\tsta _L1+2",
+				"\tlda #10",
+				"_L1",
+				"\tsta $ffff",
+			},
+		},
+		{
+			name: "var value, no-space comma",
+			line: "POKE waddrvar,valvar",
+			wantAsm: []string{
+				"\tlda waddrvar",
+				"\tsta _L1+1",
+				"\tlda waddrvar+1",
+				"\tsta _L1+2",
+				"\tlda valvar",
+				"_L1",
+				"\tsta $ffff",
+			},
+		},
+		{
+			name: "word var value (uses low byte), no-space comma",
+			line: "POKE waddrvar,wvalvar",
+			wantAsm: []string{
+				"\tlda waddrvar",
+				"\tsta _L1+1",
+				"\tlda waddrvar+1",
+				"\tsta _L1+2",
+				"\tlda wvalvar",
+				"_L1",
+				"\tsta $ffff",
+			},
+		},
+		{
+			name: "literal value, spaced comma",
+			line: "POKE waddrvar , 10",
+			wantAsm: []string{
+				"\tlda waddrvar",
+				"\tsta _L1+1",
+				"\tlda waddrvar+1",
+				"\tsta _L1+2",
+				"\tlda #10",
+				"_L1",
+				"\tsta $ffff",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := newCtx()
+			cmd := &PokeCommand{}
+			line := newLine(tt.line, ctx.Pragma)
+
+			if err := cmd.Interpret(line, ctx); err != nil {
+				t.Fatalf("Interpret() error = %v", err)
+			}
+			asm, err := cmd.Generate(ctx)
+			if err != nil {
+				t.Fatalf("Generate() error = %v", err)
+			}
+			if !equalAsm(asm, tt.wantAsm) {
+				t.Errorf("Generate() mismatch\ngot:\n%s\nwant:\n%s",
+					strings.Join(asm, "\n"),
+					strings.Join(tt.wantAsm, "\n"))
+			}
+		})
+	}
+}
+
+// =============================================================================
+// POKEW Case 4 — Direct addressing
+// =============================================================================
+
+func TestPokeWDirectAddr(t *testing.T) {
+	tests := []struct {
+		name    string
+		line    string
+		wantAsm []string
+	}{
+		{
+			name: "literal value, no-space comma",
+			line: "POKEW $d020,101",
+			wantAsm: []string{
+				"\tlda #$65",
+				"\tsta 53280",
+				"\tlda #$00",
+				"\tsta 53281",
+			},
+		},
+		{
+			name: "literal value >255, no-space comma",
+			line: "POKEW $d020,$1234",
+			wantAsm: []string{
+				"\tlda #$34",
+				"\tsta 53280",
+				"\tlda #$12",
+				"\tsta 53281",
+			},
+		},
+		{
+			name: "word var value, no-space comma",
+			line: "POKEW $d020,wvalvar",
+			wantAsm: []string{
+				"\tlda wvalvar",
+				"\tsta 53280",
+				"\tlda wvalvar+1",
+				"\tsta 53281",
+			},
+		},
+		{
+			name: "word var value, spaced comma",
+			line: "POKEW $d020 , wvalvar",
+			wantAsm: []string{
+				"\tlda wvalvar",
+				"\tsta 53280",
+				"\tlda wvalvar+1",
+				"\tsta 53281",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := newCtx()
+			cmd := &PokeWCommand{}
+			line := newLine(tt.line, ctx.Pragma)
+
+			if err := cmd.Interpret(line, ctx); err != nil {
+				t.Fatalf("Interpret() error = %v", err)
+			}
+			asm, err := cmd.Generate(ctx)
+			if err != nil {
+				t.Fatalf("Generate() error = %v", err)
+			}
+			if !equalAsm(asm, tt.wantAsm) {
+				t.Errorf("Generate() mismatch\ngot:\n%s\nwant:\n%s",
+					strings.Join(asm, "\n"),
+					strings.Join(tt.wantAsm, "\n"))
+			}
+		})
+	}
+}
+
+// =============================================================================
+// POKEW Case 1 — ZP pointer (indexed indirect, two stores)
+// =============================================================================
+
+func TestPokeWZPPointer(t *testing.T) {
+	tests := []struct {
+		name    string
+		line    string
+		wantAsm []string
+	}{
+		{
+			name: "no offset, literal value, no-space comma",
+			line: "POKEW zpptr,101",
+			wantAsm: []string{
+				"\tldy #0",
+				"\tlda #$65",
+				"\tsta (zpptr),y",
+				"\tiny",
+				"\tlda #$00",
+				"\tsta (zpptr),y",
+			},
+		},
+		{
+			name: "no offset, word var value, no-space comma",
+			line: "POKEW zpptr,wvalvar",
+			wantAsm: []string{
+				"\tldy #0",
+				"\tlda wvalvar",
+				"\tsta (zpptr),y",
+				"\tiny",
+				"\tlda wvalvar+1",
+				"\tsta (zpptr),y",
+			},
+		},
+		{
+			name: "literal offset, literal value, no-space comma",
+			line: "POKEW zpptr[5],101",
+			wantAsm: []string{
+				"\tldy #5",
+				"\tlda #$65",
+				"\tsta (zpptr),y",
+				"\tiny",
+				"\tlda #$00",
+				"\tsta (zpptr),y",
+			},
+		},
+		{
+			name: "literal offset, word var value, no-space comma",
+			line: "POKEW zpptr[5],wvalvar",
+			wantAsm: []string{
+				"\tldy #5",
+				"\tlda wvalvar",
+				"\tsta (zpptr),y",
+				"\tiny",
+				"\tlda wvalvar+1",
+				"\tsta (zpptr),y",
+			},
+		},
+		{
+			name: "literal offset, literal value, spaced comma",
+			line: "POKEW zpptr[5] , 101",
+			wantAsm: []string{
+				"\tldy #5",
+				"\tlda #$65",
+				"\tsta (zpptr),y",
+				"\tiny",
+				"\tlda #$00",
+				"\tsta (zpptr),y",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := newCtx()
+			cmd := &PokeWCommand{}
+			line := newLine(tt.line, ctx.Pragma)
+
+			if err := cmd.Interpret(line, ctx); err != nil {
+				t.Fatalf("Interpret() error = %v", err)
+			}
+			asm, err := cmd.Generate(ctx)
+			if err != nil {
+				t.Fatalf("Generate() error = %v", err)
+			}
+			if !equalAsm(asm, tt.wantAsm) {
+				t.Errorf("Generate() mismatch\ngot:\n%s\nwant:\n%s",
+					strings.Join(asm, "\n"),
+					strings.Join(tt.wantAsm, "\n"))
+			}
+		})
+	}
+}
+
+// =============================================================================
+// POKEW Case 2 — Byte variable address (zero-page indexed)
+// =============================================================================
+
+func TestPokeWByteAddr(t *testing.T) {
+	tests := []struct {
+		name    string
+		line    string
+		wantAsm []string
+	}{
+		{
+			name: "literal value, no-space comma",
+			line: "POKEW byaddr,101",
+			wantAsm: []string{
+				"\tldx byaddr",
+				"\tlda #$65",
+				"\tsta $00,x",
+				"\tinx",
+				"\tlda #$00",
+				"\tsta $00,x",
+			},
+		},
+		{
+			name: "word var value, no-space comma",
+			line: "POKEW byaddr,wvalvar",
+			wantAsm: []string{
+				"\tldx byaddr",
+				"\tlda wvalvar",
+				"\tsta $00,x",
+				"\tinx",
+				"\tlda wvalvar+1",
+				"\tsta $00,x",
+			},
+		},
+		{
+			name: "literal value, spaced comma",
+			line: "POKEW byaddr , 101",
+			wantAsm: []string{
+				"\tldx byaddr",
+				"\tlda #$65",
+				"\tsta $00,x",
+				"\tinx",
+				"\tlda #$00",
+				"\tsta $00,x",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := newCtx()
+			cmd := &PokeWCommand{}
+			line := newLine(tt.line, ctx.Pragma)
+
+			if err := cmd.Interpret(line, ctx); err != nil {
+				t.Fatalf("Interpret() error = %v", err)
+			}
+			asm, err := cmd.Generate(ctx)
+			if err != nil {
+				t.Fatalf("Generate() error = %v", err)
+			}
+			if !equalAsm(asm, tt.wantAsm) {
+				t.Errorf("Generate() mismatch\ngot:\n%s\nwant:\n%s",
+					strings.Join(asm, "\n"),
+					strings.Join(tt.wantAsm, "\n"))
+			}
+		})
+	}
+}
+
+// =============================================================================
+// POKEW Case 3 — Word variable address (self-modifying code)
+// =============================================================================
+
+func TestPokeWSMWordAddr(t *testing.T) {
+	tests := []struct {
+		name    string
+		line    string
+		wantAsm []string
+	}{
+		{
+			name: "literal value, no-space comma",
+			line: "POKEW waddrvar,101",
+			wantAsm: []string{
+				"\tlda waddrvar",
+				"\tsta _L1+1",
+				"\tsta _L2+1",
+				"\tlda waddrvar+1",
+				"\tsta _L1+2",
+				"\tsta _L2+2",
+				"\tlda #$65",
+				"_L1",
+				"\tsta $ffff",
+				"\tinc _L2+1",
+				"\tbne _L2",
+				"\tinc _L2+2",
+				"_L2",
+				"\tlda #$00",
+				"\tsta $ffff",
+			},
+		},
+		{
+			name: "word var value, no-space comma",
+			line: "POKEW waddrvar,wvalvar",
+			wantAsm: []string{
+				"\tlda waddrvar",
+				"\tsta _L1+1",
+				"\tsta _L2+1",
+				"\tlda waddrvar+1",
+				"\tsta _L1+2",
+				"\tsta _L2+2",
+				"\tlda wvalvar",
+				"_L1",
+				"\tsta $ffff",
+				"\tinc _L2+1",
+				"\tbne _L2",
+				"\tinc _L2+2",
+				"_L2",
+				"\tlda wvalvar+1",
+				"\tsta $ffff",
+			},
+		},
+		{
+			name: "literal value, spaced comma",
+			line: "POKEW waddrvar , 101",
+			wantAsm: []string{
+				"\tlda waddrvar",
+				"\tsta _L1+1",
+				"\tsta _L2+1",
+				"\tlda waddrvar+1",
+				"\tsta _L1+2",
+				"\tsta _L2+2",
+				"\tlda #$65",
+				"_L1",
+				"\tsta $ffff",
+				"\tinc _L2+1",
+				"\tbne _L2",
+				"\tinc _L2+2",
+				"_L2",
+				"\tlda #$00",
+				"\tsta $ffff",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := newCtx()
+			cmd := &PokeWCommand{}
+			line := newLine(tt.line, ctx.Pragma)
+
+			if err := cmd.Interpret(line, ctx); err != nil {
+				t.Fatalf("Interpret() error = %v", err)
+			}
+			asm, err := cmd.Generate(ctx)
+			if err != nil {
+				t.Fatalf("Generate() error = %v", err)
+			}
+			if !equalAsm(asm, tt.wantAsm) {
+				t.Errorf("Generate() mismatch\ngot:\n%s\nwant:\n%s",
+					strings.Join(asm, "\n"),
+					strings.Join(tt.wantAsm, "\n"))
+			}
+		})
+	}
+}
+
+
+
+// =============================================================================
+// Error cases
+// =============================================================================
+
+func TestPokeErrors(t *testing.T) {
+	tests := []struct {
+		name    string
+		line    string
+		wantErr string
+	}{
+		{
+			name:    "offset on non-ZP word pointer",
+			line:    "POKE waddrvar[5],10",
+			wantErr: "POKE: offset",
+		},
+		{
+			name:    "value out of byte range",
+			line:    "POKE $d020,256",
+			wantErr: "out of byte range",
+		},
+		{
+			name:    "POKEW with byte variable as value",
+			line:    "POKEW $d020,valvar",
+			wantErr: "cannot use byte variable",
+		},
+		{
+			name:    "POKEW self-referential (zp pointer == value)",
+			line:    "POKEW zpptr,zpptr",
+			wantErr: "writing pointer",
+		},
+		{
+			name:    "invalid separator",
+			line:    "POKE $d020 WRONG 5",
+			wantErr: "must be 'WITH' or ','",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := newCtx()
+
+			if strings.HasPrefix(tt.line, "POKEW") {
+				cmd := &PokeWCommand{}
+				line := newLine(tt.line, ctx.Pragma)
+				err := cmd.Interpret(line, ctx)
+				if err == nil {
+					t.Fatal("Interpret() expected error but got nil")
+				}
+				if !strings.Contains(err.Error(), tt.wantErr) {
+					t.Errorf("Interpret() error = %q, want containing %q", err.Error(), tt.wantErr)
+				}
+				return
+			}
+
+			cmd := &PokeCommand{}
+			line := newLine(tt.line, ctx.Pragma)
+			err := cmd.Interpret(line, ctx)
+			if err == nil {
+				t.Fatal("Interpret() expected error but got nil")
+			}
+			if !strings.Contains(err.Error(), tt.wantErr) {
+				t.Errorf("Interpret() error = %q, want containing %q", err.Error(), tt.wantErr)
+			}
+		})
+	}
+}
+
+func TestPokePragmaImmutable(t *testing.T) {
+	t.Run("SM byte addr with USE_IMMUTABLE_CODE", func(t *testing.T) {
+		pragma := preproc.NewPragma()
+		pragma.AddPragma("_P_USE_IMMUTABLE_CODE", "1")
+		ctx := compiler.NewCompilerContext(pragma)
+		ctx.SymbolTable.AddVar("addrvar", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+
+		cmd := &PokeCommand{}
+		line := preproc.Line{
+			Text:           "POKE addrvar,10",
+			Kind:           preproc.Source,
+			PragmaSetIndex: pragma.GetCurrentPragmaSetIndex(),
+		}
+
+		if err := cmd.Interpret(line, ctx); err != nil {
+			t.Fatalf("Interpret() error = %v", err)
+		}
+		_, err := cmd.Generate(ctx)
+		if err == nil {
+			t.Fatal("Generate() expected error with USE_IMMUTABLE_CODE")
+		}
+		if !strings.Contains(err.Error(), "USE_IMMUTABLE_CODE") {
+			t.Errorf("Generate() error = %q, want containing USE_IMMUTABLE_CODE", err.Error())
+		}
+	})
+
+	t.Run("SM word addr with USE_IMMUTABLE_CODE", func(t *testing.T) {
+		pragma := preproc.NewPragma()
+		pragma.AddPragma("_P_USE_IMMUTABLE_CODE", "1")
+		ctx := compiler.NewCompilerContext(pragma)
+		ctx.SymbolTable.AddVar("waddrvar", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+
+		cmd := &PokeCommand{}
+		line := preproc.Line{
+			Text:           "POKE waddrvar,10",
+			Kind:           preproc.Source,
+			PragmaSetIndex: pragma.GetCurrentPragmaSetIndex(),
+		}
+
+		if err := cmd.Interpret(line, ctx); err != nil {
+			t.Fatalf("Interpret() error = %v", err)
+		}
+		_, err := cmd.Generate(ctx)
+		if err == nil {
+			t.Fatal("Generate() expected error with USE_IMMUTABLE_CODE")
+		}
+		if !strings.Contains(err.Error(), "USE_IMMUTABLE_CODE") {
+			t.Errorf("Generate() error = %q, want containing USE_IMMUTABLE_CODE", err.Error())
+		}
+	})
+
+	t.Run("ZP pointer is allowed with USE_IMMUTABLE_CODE", func(t *testing.T) {
+		pragma := preproc.NewPragma()
+		pragma.AddPragma("_P_USE_IMMUTABLE_CODE", "1")
+		ctx := compiler.NewCompilerContext(pragma)
+		ctx.SymbolTable.AddAbsolute("zpptr", "", compiler.KindWord, 0x80, preproc.Line{Filename: "test.c65", LineNo: 1})
+
+		cmd := &PokeCommand{}
+		line := preproc.Line{
+			Text:           "POKE zpptr,10",
+			Kind:           preproc.Source,
+			PragmaSetIndex: pragma.GetCurrentPragmaSetIndex(),
+		}
+
+		if err := cmd.Interpret(line, ctx); err != nil {
+			t.Fatalf("Interpret() error = %v", err)
+		}
+		asm, err := cmd.Generate(ctx)
+		if err != nil {
+			t.Fatalf("Generate() error = %v (ZP pointers should be allowed)", err)
+		}
+		expected := []string{
+			"\tldy #0",
+			"\tlda #10",
+			"\tsta (zpptr),y",
+		}
+		if !equalAsm(asm, expected) {
+			t.Errorf("Generate() mismatch\ngot:\n%s\nwant:\n%s",
+				strings.Join(asm, "\n"),
+				strings.Join(expected, "\n"))
+		}
+	})
+
+	t.Run("direct addr is allowed with USE_IMMUTABLE_CODE", func(t *testing.T) {
+		pragma := preproc.NewPragma()
+		pragma.AddPragma("_P_USE_IMMUTABLE_CODE", "1")
+		ctx := compiler.NewCompilerContext(pragma)
+
+		cmd := &PokeCommand{}
+		line := preproc.Line{
+			Text:           "POKE $d020,5",
+			Kind:           preproc.Source,
+			PragmaSetIndex: pragma.GetCurrentPragmaSetIndex(),
+		}
+
+		if err := cmd.Interpret(line, ctx); err != nil {
+			t.Fatalf("Interpret() error = %v", err)
+		}
+		asm, err := cmd.Generate(ctx)
+		if err != nil {
+			t.Fatalf("Generate() error = %v (direct addr should be allowed)", err)
+		}
+		expected := []string{
+			"\tlda #5",
+			"\tsta 53280",
+		}
+		if !equalAsm(asm, expected) {
+			t.Errorf("Generate() mismatch\ngot:\n%s\nwant:\n%s",
+				strings.Join(asm, "\n"),
+				strings.Join(expected, "\n"))
+		}
+	})
+}

internal/commands/pokew.go

@@ -37,7 +37,7 @@ type PokeWCommand struct {
 }
 
 func (c *PokeWCommand) WillHandle(line preproc.Line) bool {
-	params, err := utils.ParseParams(line.Text)
+	params, err := utils.ParseParams(utils.NormalizeCommas(line.Text))
 	if err != nil || len(params) != 4 {
 		return false
 	}
@@ -61,7 +61,7 @@ func (c *PokeWCommand) Interpret(line preproc.Line, ctx *compiler.CompilerContex
 	// Store pragma set for Generate phase
 	c.pragmaSet = ctx.Pragma.GetPragmaSetByIndex(line.PragmaSetIndex)
 
-	params, err := utils.ParseParams(line.Text)
+	params, err := utils.ParseParams(utils.NormalizeCommas(line.Text))
 	if err != nil {
 		return err
 	}

internal/commands/xor.go

@@ -200,6 +200,21 @@ func (c *XorCommand) Generate(_ *compiler.CompilerContext) ([]string, error) {
 	}
 
 	// At least one param is a variable - generate XOR code
+
+	// Same variable on both sides: a ^ a = 0
+	if c.param1IsVar && c.param2IsVar && c.param1VarName == c.param2VarName {
+		asm = append(asm, "\tlda #0")
+		asm = append(asm, fmt.Sprintf("\tsta %s", c.destVarName))
+		if c.destVarKind == compiler.KindWord {
+			asm = append(asm, fmt.Sprintf("\tsta %s+1", c.destVarName))
+		}
+		return asm, nil
+	}
+
+	// If param1 is literal 0, just load param2 directly (0 XOR a = a)
+	if !c.param1IsVar && uint8(c.param1Value&0xFF) == 0 && c.param2IsVar {
+		asm = append(asm, fmt.Sprintf("\tlda %s", c.param2VarName))
+	} else {
 		// Load param1
 		if c.param1IsVar {
 			asm = append(asm, fmt.Sprintf("\tlda %s", c.param1VarName))
@@ -207,12 +222,13 @@ func (c *XorCommand) Generate(_ *compiler.CompilerContext) ([]string, error) {
 			asm = append(asm, fmt.Sprintf("\tlda #$%02x", uint8(c.param1Value&0xFF)))
 		}
 
-	// XOR with param2
+		// XOR with param2 (skip if literal 0, as eor #0 is a no-op)
 		if c.param2IsVar {
 			asm = append(asm, fmt.Sprintf("\teor %s", c.param2VarName))
-	} else {
+		} else if uint8(c.param2Value&0xFF) != 0 {
 			asm = append(asm, fmt.Sprintf("\teor #$%02x", uint8(c.param2Value&0xFF)))
 		}
+	}
 
 	// Store low byte
 	asm = append(asm, fmt.Sprintf("\tsta %s", c.destVarName))

internal/commands/xor_test.go

@@ -463,6 +463,44 @@ func TestXorCommand_NewSyntax(t *testing.T) {
 				"\tsta result",
 			},
 		},
+		{
+			name: "byte ^ 0 -> byte (optimization: skip eor #0)",
+			line: "result = a ^ 0",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda a",
+				"\tsta result",
+			},
+		},
+		{
+			name: "0 ^ byte -> byte (optimization: skip eor #0)",
+			line: "result = 0 ^ a",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda a",
+				"\tsta result",
+			},
+		},
+		{
+			name: "byte ^ 0 -> word (optimization: skip eor #0)",
+			line: "result = a ^ 0",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda a",
+				"\tsta result",
+				"\tlda #0",
+				"\tsta result+1",
+			},
+		},
 		{
 			name: "constant folding",
 			line: "result = 255 ^ 170",
@@ -501,6 +539,31 @@ func TestXorCommand_NewSyntax(t *testing.T) {
 				"\tsta result",
 			},
 		},
+		{
+			name: "byte ^ byte -> byte (same variable: a ^ a = 0)",
+			line: "result = a ^ a",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("a", "", compiler.KindByte, 0xFF, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindByte, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #0",
+				"\tsta result",
+			},
+		},
+		{
+			name: "word ^ word -> word (same variable: x ^ x = 0)",
+			line: "result = x ^ x",
+			setupVars: func(st *compiler.SymbolTable) {
+				st.AddVar("x", "", compiler.KindWord, 0x1234, preproc.Line{Filename: "test.c65", LineNo: 1})
+				st.AddVar("result", "", compiler.KindWord, 0, preproc.Line{Filename: "test.c65", LineNo: 1})
+			},
+			wantAsm: []string{
+				"\tlda #0",
+				"\tsta result",
+				"\tsta result+1",
+			},
+		},
 		{
 			name: "error: unknown destination",
 			line: "unknown = a ^ b",

internal/compiler/compiler.go

@@ -42,11 +42,13 @@ func (c *Compiler) Registry() *CommandRegistry {
 func (c *Compiler) Compile(lines []preproc.Line) ([]string, error) {
 	var codeOutput []string
 	var lastKind = preproc.Source
-	var scriptBuffer []string
+	var scriptBuffer []preproc.Line
 	var scriptIsLibrary bool
 	var macroBuffer []string
 	var currentMacroName string
 	var currentMacroParams []string
+	var currentMacroSourceFile string
+	var currentMacroStartLine int
 	var currentAsmTarget *[]string // nil = no active ASM block, or points to target slice
 
 	// Reset deferred ASM storage for this compilation
@@ -77,12 +79,16 @@ func (c *Compiler) Compile(lines []preproc.Line) ([]string, error) {
 						Name:       currentMacroName,
 						Params:     currentMacroParams,
 						Body:       macroBuffer,
+						SourceFile: currentMacroSourceFile,
+						StartLine:  currentMacroStartLine,
 					}
 					codeOutput = append(codeOutput, fmt.Sprintf("; ENDSCRIPT MACRO %s", currentMacroName))
 				}
 				macroBuffer = nil
 				currentMacroName = ""
 				currentMacroParams = nil
+				currentMacroSourceFile = ""
+				currentMacroStartLine = 0
 			}
 
 			// Close previous Assembler block
@@ -163,7 +169,7 @@ func (c *Compiler) Compile(lines []preproc.Line) ([]string, error) {
 							return nil, fmt.Errorf("compilation failed")
 						}
 
-						macroOutput, err := ExecuteMacro(macroName, args, c.ctx)
+						macroOutput, err := ExecuteMacro(macroName, args, c.ctx, line.PragmaSetIndex)
 						if err != nil {
 							c.printErrorWithContext(lines, i, fmt.Errorf("macro %s: %w", macroName, err))
 							return nil, fmt.Errorf("compilation failed")
@@ -199,12 +205,17 @@ func (c *Compiler) Compile(lines []preproc.Line) ([]string, error) {
 				*currentAsmTarget = append(*currentAsmTarget, codePart+commentPart)
 			} else if line.Kind == preproc.Script || line.Kind == preproc.ScriptLibrary {
 				// Collect script lines for execution
-				scriptBuffer = append(scriptBuffer, line.Text)
+				scriptBuffer = append(scriptBuffer, line)
 			} else if line.Kind == preproc.ScriptMacroDef {
 				// Skip the header line (already parsed in transition)
 				if strings.HasPrefix(strings.TrimSpace(line.Text), "SCRIPT MACRO ") {
 					continue
 				}
+				// Capture source provenance from first body line
+				if len(macroBuffer) == 0 {
+					currentMacroSourceFile = line.Filename
+					currentMacroStartLine = line.LineNo
+				}
 				// Collect macro body lines
 				macroBuffer = append(macroBuffer, line.Text)
 			}

internal/compiler/compiler_test.go

@@ -165,7 +165,7 @@ func TestExecuteScript_BasicPrint(t *testing.T) {
 		"  print('  nop')",
 	}
 
-	output, err := executeScript(scriptLines, ctx, false)
+	output, err := testExecuteScript(scriptLines, ctx, false)
 	if err != nil {
 		t.Fatalf("executeScript failed: %v", err)
 	}
@@ -189,7 +189,7 @@ func TestExecuteScript_EmptyOutput(t *testing.T) {
 		"x = 1 + 1",
 	}
 
-	output, err := executeScript(scriptLines, ctx, false)
+	output, err := testExecuteScript(scriptLines, ctx, false)
 	if err != nil {
 		t.Fatalf("executeScript failed: %v", err)
 	}
@@ -210,7 +210,7 @@ func TestExecuteScript_Library_DefinesFunction(t *testing.T) {
 		"    print('  nop')",
 	}
 
-	_, err := executeScript(libraryLines, ctx, true)
+	_, err := testExecuteScript(libraryLines, ctx, true)
 	if err != nil {
 		t.Fatalf("library executeScript failed: %v", err)
 	}
@@ -232,7 +232,7 @@ func TestExecuteScript_Library_FunctionCallableFromScript(t *testing.T) {
 		"    print('  nop')",
 	}
 
-	_, err := executeScript(libraryLines, ctx, true)
+	_, err := testExecuteScript(libraryLines, ctx, true)
 	if err != nil {
 		t.Fatalf("library executeScript failed: %v", err)
 	}
@@ -242,7 +242,7 @@ func TestExecuteScript_Library_FunctionCallableFromScript(t *testing.T) {
 		"emit_nops(2)",
 	}
 
-	output, err := executeScript(scriptLines, ctx, false)
+	output, err := testExecuteScript(scriptLines, ctx, false)
 	if err != nil {
 		t.Fatalf("script executeScript failed: %v", err)
 	}
@@ -267,7 +267,7 @@ func TestExecuteScript_MultipleLibraries_Accumulate(t *testing.T) {
 		"def func_a():",
 		"  print('  ; from a')",
 	}
-	_, err := executeScript(lib1, ctx, true)
+	_, err := testExecuteScript(lib1, ctx, true)
 	if err != nil {
 		t.Fatalf("lib1 failed: %v", err)
 	}
@@ -277,7 +277,7 @@ func TestExecuteScript_MultipleLibraries_Accumulate(t *testing.T) {
 		"def func_b():",
 		"  print('  ; from b')",
 	}
-	_, err = executeScript(lib2, ctx, true)
+	_, err = testExecuteScript(lib2, ctx, true)
 	if err != nil {
 		t.Fatalf("lib2 failed: %v", err)
 	}
@@ -295,7 +295,7 @@ func TestExecuteScript_MultipleLibraries_Accumulate(t *testing.T) {
 		"func_a()",
 		"func_b()",
 	}
-	output, err := executeScript(scriptLines, ctx, false)
+	output, err := testExecuteScript(scriptLines, ctx, false)
 	if err != nil {
 		t.Fatalf("script failed: %v", err)
 	}
@@ -322,7 +322,7 @@ func TestExecuteScript_RegularScript_DoesNotPersist(t *testing.T) {
 		"local_func()",
 	}
 
-	output, err := executeScript(scriptLines, ctx, false)
+	output, err := testExecuteScript(scriptLines, ctx, false)
 	if err != nil {
 		t.Fatalf("script failed: %v", err)
 	}
@@ -352,7 +352,7 @@ func TestExecuteMacro_Basic(t *testing.T) {
 	}
 
 	// Execute macro
-	output, err := ExecuteMacro("test_macro", []string{"3"}, ctx)
+	output, err := ExecuteMacro("test_macro", []string{"3"}, ctx, 0)
 	if err != nil {
 		t.Fatalf("ExecuteMacro failed: %v", err)
 	}
@@ -377,7 +377,7 @@ func TestExecuteMacro_WithLibraryFunction(t *testing.T) {
 		"def emit_nop():",
 		"  print('  nop')",
 	}
-	_, err := executeScript(lib, ctx, true)
+	_, err := testExecuteScript(lib, ctx, true)
 	if err != nil {
 		t.Fatalf("library failed: %v", err)
 	}
@@ -392,7 +392,7 @@ func TestExecuteMacro_WithLibraryFunction(t *testing.T) {
 	}
 
 	// Execute macro
-	output, err := ExecuteMacro("nop_macro", []string{}, ctx)
+	output, err := ExecuteMacro("nop_macro", []string{}, ctx, 0)
 	if err != nil {
 		t.Fatalf("ExecuteMacro failed: %v", err)
 	}
@@ -416,7 +416,7 @@ func TestExecuteMacro_StringParameter(t *testing.T) {
 	}
 
 	// Execute with identifier (should be passed as string)
-	output, err := ExecuteMacro("jump_to", []string{"my_label"}, ctx)
+	output, err := ExecuteMacro("jump_to", []string{"my_label"}, ctx, 0)
 	if err != nil {
 		t.Fatalf("ExecuteMacro failed: %v", err)
 	}
@@ -451,7 +451,7 @@ func TestExecuteMacro_LocalVariableExpansion(t *testing.T) {
 	}
 
 	// Execute macro with "myvar" as argument - should expand |myvar| to testfunc_myvar
-	output, err := ExecuteMacro("load_var", []string{"myvar"}, ctx)
+	output, err := ExecuteMacro("load_var", []string{"myvar"}, ctx, 0)
 	if err != nil {
 		t.Fatalf("ExecuteMacro failed: %v", err)
 	}
@@ -500,7 +500,7 @@ func TestExecuteMacro_LocalVariableExpansion_MultipleVars(t *testing.T) {
 	}
 
 	// Execute macro with actual variable names as arguments
-	output, err := ExecuteMacro("table_lookup", []string{"scroll_color_table", "color_index", "row_color"}, ctx)
+	output, err := ExecuteMacro("table_lookup", []string{"scroll_color_table", "color_index", "row_color"}, ctx, 0)
 	if err != nil {
 		t.Fatalf("ExecuteMacro failed: %v", err)
 	}
@@ -540,7 +540,7 @@ func TestExecuteScript_LocalVariableExpansion(t *testing.T) {
 		"print('  inc |counter|')",
 	}
 
-	output, err := executeScript(scriptLines, ctx, false)
+	output, err := testExecuteScript(scriptLines, ctx, false)
 	if err != nil {
 		t.Fatalf("executeScript failed: %v", err)
 	}
@@ -569,7 +569,7 @@ func TestExecuteScript_Library_GlobalVariableExpansion(t *testing.T) {
 		"  print('  inc |global_counter|')",
 	}
 
-	_, err := executeScript(libraryLines, ctx, true)
+	_, err := testExecuteScript(libraryLines, ctx, true)
 	if err != nil {
 		t.Fatalf("library script failed: %v", err)
 	}
@@ -579,7 +579,7 @@ func TestExecuteScript_Library_GlobalVariableExpansion(t *testing.T) {
 		"inc_global()",
 	}
 
-	output, err := executeScript(scriptLines, ctx, false)
+	output, err := testExecuteScript(scriptLines, ctx, false)
 	if err != nil {
 		t.Fatalf("executeScript failed: %v", err)
 	}
@@ -610,7 +610,7 @@ func TestExecuteScript_Library_VariableExpansionAtDefinitionTime(t *testing.T) {
 	}
 
 	// Library defined at global scope - |local_var| won't find caller's local
-	_, err := executeScript(libraryLines, ctx, true)
+	_, err := testExecuteScript(libraryLines, ctx, true)
 	if err != nil {
 		t.Fatalf("library script failed: %v", err)
 	}
@@ -625,7 +625,7 @@ func TestExecuteScript_Library_VariableExpansionAtDefinitionTime(t *testing.T) {
 		"use_local()",
 	}
 
-	output, err := executeScript(scriptLines, ctx, false)
+	output, err := testExecuteScript(scriptLines, ctx, false)
 	if err != nil {
 		t.Fatalf("executeScript failed: %v", err)
 	}
@@ -1219,3 +1219,96 @@ func TestAsmAfterVarsWithVariables(t *testing.T) {
 		t.Errorf("expected ASM block in deferred section")
 	}
 }
+
+// testExecuteScript is a test helper that wraps executeScript with convenient types
+func testExecuteScript(scriptLines []string, ctx *CompilerContext, isLibrary bool) ([]string, error) {
+	lines := make([]preproc.Line, len(scriptLines))
+	for i, text := range scriptLines {
+		lines[i] = preproc.Line{
+			Text:     text,
+			Filename: "test.c65",
+			LineNo:   i + 1,
+		}
+	}
+	return executeScript(lines, ctx, isLibrary)
+}
+
+func TestCompile_MultipleScriptBlocks_Success(t *testing.T) {
+	// Two consecutive SCRIPT blocks should execute independently
+	pragma := preproc.NewPragma()
+	comp := NewCompiler(pragma)
+
+	lines := []preproc.Line{
+		// Block 1: print("hello")
+		{Text: "print('hello')", Filename: "test.c65", LineNo: 2, Kind: preproc.Script},
+		// ENDSCRIPT boundary (empty Source)
+		{Text: "", Filename: "test.c65", LineNo: 3, Kind: preproc.Source},
+		// Block 2: print("world")
+		{Text: "print('world')", Filename: "test.c65", LineNo: 5, Kind: preproc.Script},
+		// ENDSCRIPT boundary (empty Source)
+		{Text: "", Filename: "test.c65", LineNo: 6, Kind: preproc.Source},
+	}
+
+	output, err := comp.Compile(lines)
+	if err != nil {
+		t.Fatalf("Compile failed: %v", err)
+	}
+
+	// Output should contain both "hello" and "world" in that order
+	foundHello := false
+	foundWorld := false
+	helloBeforeWorld := false
+	for _, line := range output {
+		if strings.Contains(line, "hello") && !foundHello {
+			foundHello = true
+		}
+		if foundHello && strings.Contains(line, "world") && !foundWorld {
+			foundWorld = true
+			helloBeforeWorld = true
+		}
+	}
+	if !foundHello {
+		t.Error("expected 'hello' from block 1 in output")
+	}
+	if !foundWorld {
+		t.Error("expected 'world' from block 2 in output")
+	}
+	if !helloBeforeWorld {
+		t.Error("expected 'hello' before 'world' in output")
+	}
+}
+
+func TestCompile_MultipleScriptBlocks_ErrorInBlock2(t *testing.T) {
+	// Error in second SCRIPT block should not be confused with block 1
+	pragma := preproc.NewPragma()
+	comp := NewCompiler(pragma)
+
+	lines := []preproc.Line{
+		// Block 1: no error
+		{Text: "x = 1", Filename: "test.c65", LineNo: 2, Kind: preproc.Script},
+		{Text: "print(x)", Filename: "test.c65", LineNo: 3, Kind: preproc.Script},
+		// ENDSCRIPT boundary
+		{Text: "", Filename: "test.c65", LineNo: 4, Kind: preproc.Source},
+		// Block 2: error at line 8 (division by zero)
+		{Text: "y = 2", Filename: "test.c65", LineNo: 6, Kind: preproc.Script},
+		{Text: "z = y + 1", Filename: "test.c65", LineNo: 7, Kind: preproc.Script},
+		{Text: "1 / 0", Filename: "test.c65", LineNo: 8, Kind: preproc.Script},
+		// ENDSCRIPT boundary
+		{Text: "", Filename: "test.c65", LineNo: 9, Kind: preproc.Source},
+	}
+
+	_, err := comp.Compile(lines)
+	if err == nil {
+		t.Fatal("expected error from block 2, got none")
+	}
+
+	errMsg := err.Error()
+	if !strings.Contains(errMsg, "Starlark error") {
+		t.Errorf("expected Starlark error, got: %s", errMsg)
+	}
+	// Verify error references the correct source line in block 2 (line 8 = division by zero)
+	if !strings.Contains(errMsg, ":8:") {
+		t.Errorf("error should reference source line 8 in block 2, got: %s", errMsg)
+	}
+}
+

internal/compiler/context.go

@@ -11,6 +11,8 @@ type ScriptMacro struct {
 	Name       string   // macro name
 	Params     []string // parameter names
 	Body       []string // Starlark code lines (the macro body)
+	SourceFile string   // source file where macro is defined
+	StartLine  int      // 1-based line number in source file of first body line
 }
 
 // CompilerContext holds all shared resources needed by commands during compilation
@@ -41,6 +43,11 @@ type CompilerContext struct {
 
 	// ScriptMacros holds named macro definitions from SCRIPT MACRO blocks
 	ScriptMacros map[string]*ScriptMacro
+
+	// ProjectRoot is the absolute path of the directory containing the main input .c65 file.
+	// Used by scripting built-ins (load_binary, load_text) to resolve relative file paths
+	// and enforce security (no access outside project root).
+	ProjectRoot string
 }
 
 // NewCompilerContext creates a new compiler context with initialized resources

internal/compiler/scriptexec.go

@@ -2,29 +2,229 @@ package compiler
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strconv"
 	"strings"
 
+	"c65gm/internal/preproc"
 	"c65gm/internal/utils"
 
 	"go.starlark.net/lib/math"
 	"go.starlark.net/starlark"
 )
 
+// mapStarlarkLine maps a Starlark 1-based line number to an index into scriptLines
+// (a slice of preproc.Line). Returns -1 if the line cannot be mapped.
+// For non-library scripts, the Starlark source is:
+//
+//	Line 1: def _main():
+//	Line 2..N+1: indented script lines
+//	Line N+2: _main()
+//
+// For library scripts, lines are used as-is.
+func mapStarlarkLine(starlarkLine int, numScriptLines int, isLibrary bool) int {
+	var idx int
+	if isLibrary {
+		idx = starlarkLine - 1
+	} else {
+		idx = starlarkLine - 2
+	}
+	if idx < 0 || idx >= numScriptLines {
+		return -1
+	}
+	return idx
+}
+
+// starlarkErrorMsgLineMatch matches Starlark error messages of the form
+// "filename:LINE:COL: message" produced by resolve errors.
+var starlarkErrorMsgLineMatch = regexp.MustCompile(`^(.+):(\d+):(\d+): (.*)$`)
+
+// starlarkPosition extracts the source position from a Starlark error.
+// Returns the 1-based line number (0 if unknown).
+func starlarkPosition(err error) int {
+	var evalErr *starlark.EvalError
+	if errors.As(err, &evalErr) {
+		if len(evalErr.CallStack) > 0 {
+			top := evalErr.CallStack.At(0)
+			return int(top.Pos.Line)
+		}
+	}
+	// For non-EvalError (resolve errors), extract line from the message
+	return parseStarlarkLineFromMsg(err.Error())
+}
+
+// parseStarlarkLineFromMsg attempts to extract the Starlark line number from
+// a non-EvalError error message string. Starlark resolve errors follow the
+// format "filename:LINE:COL: message".
+func parseStarlarkLineFromMsg(msg string) int {
+	matches := starlarkErrorMsgLineMatch.FindStringSubmatch(msg)
+	if len(matches) >= 3 {
+		line, err := strconv.Atoi(matches[2])
+		if err == nil && line > 0 {
+			return line
+		}
+	}
+	return 0
+}
+
+// starlarkErrorMsg extracts just the message from a Starlark error.
+// For EvalError, it returns the Msg field directly.
+// For non-EvalError (resolve errors), it strips the "filename:LINE:COL: " prefix.
+func starlarkErrorMsg(err error) string {
+	var evalErr *starlark.EvalError
+	if errors.As(err, &evalErr) {
+		return evalErr.Msg
+	}
+	return stripStarlarkPositionFromMsg(err.Error())
+}
+
+// stripStarlarkPositionFromMsg removes the "filename:LINE:COL: " prefix from
+// a Starlark error message if present.
+func stripStarlarkPositionFromMsg(msg string) string {
+	matches := starlarkErrorMsgLineMatch.FindStringSubmatch(msg)
+	if len(matches) >= 5 {
+		return matches[4]
+	}
+	return msg
+}
+
+// printScriptErrorContext prints a Starlark error with script-block-bounded source context,
+// synthesizing SCRIPT/ENDSCRIPT boundary lines that the preprocessor discards.
+// When the original Starlark error has a call stack with frames beyond the script block
+// (e.g. a library function), those frames are shown as a backtrace below the source context.
+func printScriptErrorContext(err error, errMsg string, scriptLines []preproc.Line, errorIdx int, blockType string) {
+	if len(scriptLines) == 0 || errorIdx < 0 || errorIdx >= len(scriptLines) {
+		fmt.Fprintf(os.Stderr, "\nError: Starlark error: %s\n\n", errMsg)
+		return
+	}
+
+	line := scriptLines[errorIdx]
+	filename := line.Filename
+
+	const contextLines = 3
+
+	fmt.Fprintf(os.Stderr, "\nError: Starlark error: %s\n", errMsg)
+	fmt.Fprintf(os.Stderr, "  --> %s:%d\n\n", filename, line.LineNo)
+
+	startIdx := errorIdx - contextLines
+	if startIdx < 0 {
+		startIdx = 0
+	}
+	endIdx := errorIdx + contextLines
+	if endIdx >= len(scriptLines) {
+		endIdx = len(scriptLines) - 1
+	}
+
+	scriptMarkerLineNo := scriptLines[0].LineNo - 1
+	endScriptLineNo := scriptLines[len(scriptLines)-1].LineNo + 1
+
+	maxLineNo := endScriptLineNo
+	if scriptLines[endIdx].LineNo > maxLineNo {
+		maxLineNo = scriptLines[endIdx].LineNo
+	}
+	if scriptMarkerLineNo > maxLineNo {
+		maxLineNo = scriptMarkerLineNo
+	}
+	lineNumWidth := len(fmt.Sprintf("%d", maxLineNo))
+
+	if startIdx == 0 {
+		fmt.Fprintf(os.Stderr, "   %*d | %s\n", lineNumWidth, scriptMarkerLineNo, blockType)
+	}
+
+	for i := startIdx; i <= endIdx; i++ {
+		l := scriptLines[i]
+		marker := "   "
+		if i == errorIdx {
+			marker = ">> "
+		}
+		fmt.Fprintf(os.Stderr, "%s%*d | %s\n", marker, lineNumWidth, l.LineNo, l.Text)
+	}
+
+	if endIdx == len(scriptLines)-1 {
+		fmt.Fprintf(os.Stderr, "   %*d | END%s\n", lineNumWidth, endScriptLineNo, blockType)
+	}
+
+	// Show call stack if the error has additional frames beyond the script block
+	printStarlarkBacktrace(err, line.LineNo, filename)
+
+	fmt.Fprintf(os.Stderr, "\n")
+}
+
+// printStarlarkBacktrace prints a concise call stack from a Starlark error,
+// filtering out frames from the given scriptBlockLine and <toplevel>/_main wrappers.
+func printStarlarkBacktrace(err error, scriptBlockLine int, scriptFile string) {
+	var evalErr *starlark.EvalError
+	if !errors.As(err, &evalErr) || len(evalErr.CallStack) < 2 {
+		return
+	}
+
+	var frames []string
+	for _, cf := range evalErr.CallStack {
+		name := cf.Name
+		pos := cf.Pos
+		// Skip frames that are already shown in the bounded source context
+		if name == "<toplevel>" || name == "_main" {
+			continue
+		}
+		if int(pos.Line) == scriptBlockLine && pos.Filename() == scriptFile {
+			continue
+		}
+		if pos.Filename() != "" && int(pos.Line) > 0 {
+			frames = append(frames, fmt.Sprintf("  %s: in %s", pos.String(), name))
+		}
+	}
+	if len(frames) > 0 {
+		fmt.Fprintf(os.Stderr, "Call stack:\n%s\n", strings.Join(frames, "\n"))
+	}
+}
+
+// printScriptErrorFallback prints what we can from a Starlark error when
+// we couldn't map it to a specific source line within a script block.
+func printScriptErrorFallback(err error) {
+	fmt.Fprintf(os.Stderr, "\nError: Starlark error: %s\n", err)
+	var evalErr *starlark.EvalError
+	if errors.As(err, &evalErr) && len(evalErr.CallStack) > 0 {
+		fmt.Fprintf(os.Stderr, "Call stack:\n")
+		for _, cf := range evalErr.CallStack {
+			name := cf.Name
+			pos := cf.Pos
+			if pos.Filename() != "" && int(pos.Line) > 0 {
+				fmt.Fprintf(os.Stderr, "  %s: in %s\n", pos.String(), name)
+			}
+		}
+	}
+	fmt.Fprintf(os.Stderr, "\n")
+}
+
 // executeScript runs a Starlark script and returns the output lines.
 // If isLibrary is true, the script is executed at top level (no _main wrapper)
 // and resulting globals are persisted to ctx.ScriptLibraryGlobals.
-func executeScript(scriptLines []string, ctx *CompilerContext, isLibrary bool) ([]string, error) {
+func executeScript(scriptLines []preproc.Line, ctx *CompilerContext, isLibrary bool) ([]string, error) {
+	// Extract text from preproc.Lines
+	texts := make([]string, len(scriptLines))
+	for i, l := range scriptLines {
+		texts[i] = l.Text
+	}
+
 	// Join script lines
-	scriptText := strings.Join(scriptLines, "\n")
+	scriptText := strings.Join(texts, "\n")
 
 	// Expand |varname| -> actual variable names
 	scriptText = expandVariables(scriptText, ctx)
 
+	// Determine the source filename for Starlark
+	sourceFile := scriptLines[0].Filename
+
 	var finalScript string
+	var starlarkFilename string
 	if isLibrary {
 		// LIBRARY: execute at top level so defs become globals
 		finalScript = scriptText
+		starlarkFilename = sourceFile
 	} else {
 		// Regular SCRIPT: wrap in function (Starlark requires control flow inside functions)
 		finalScript = "def _main():\n"
@@ -32,6 +232,7 @@ func executeScript(scriptLines []string, ctx *CompilerContext, isLibrary bool) (
 			finalScript += "    " + line + "\n"
 		}
 		finalScript += "_main()\n"
+		starlarkFilename = sourceFile
 	}
 
 	// Capture print output
@@ -43,21 +244,41 @@ func executeScript(scriptLines []string, ctx *CompilerContext, isLibrary bool) (
 		},
 	}
 
-	// Set execution limit (prevent infinite loops)
-	thread.SetMaxExecutionSteps(1000000) // 1M steps
+	// Set execution limit from pragma or default (prevent infinite loops)
+	thread.SetMaxExecutionSteps(readScriptMaxSteps(ctx, scriptLines[0].PragmaSetIndex))
 
-	// Build predeclared: math module + library globals
+	// Build predeclared: math module + library globals + file I/O builtins
 	predeclared := starlark.StringDict{
 		"math":        math.Module,
+		"load_binary": makeLoadBinary(ctx.ProjectRoot),
+		"load_text":   makeLoadText(ctx.ProjectRoot),
 	}
 	for k, v := range ctx.ScriptLibraryGlobals {
 		predeclared[k] = v
 	}
 
 	// Execute
-	globals, err := starlark.ExecFile(thread, "script.star", finalScript, predeclared)
+	globals, err := starlark.ExecFile(thread, starlarkFilename, finalScript, predeclared)
 	if err != nil {
-		return nil, err
+		// Map Starlark error position back to source
+		starLine := starlarkPosition(err)
+		idx := -1
+		if starLine > 0 {
+			idx = mapStarlarkLine(starLine, len(scriptLines), isLibrary)
+		}
+		if idx >= 0 {
+			msg := starlarkErrorMsg(err)
+			blockType := "SCRIPT"
+			if isLibrary {
+				blockType = "SCRIPT LIBRARY"
+			}
+			printScriptErrorContext(err, msg, scriptLines, idx, blockType)
+			srcLine := scriptLines[idx]
+			return nil, fmt.Errorf("Starlark error: %s:%d: %s", srcLine.Filename, srcLine.LineNo, msg)
+		}
+		// Fallback: print whatever info we can extract
+		printScriptErrorFallback(err)
+		return nil, fmt.Errorf("Starlark error: %w", err)
 	}
 
 	// For LIBRARY: persist new globals (functions, variables defined at top level)
@@ -97,8 +318,149 @@ func expandVariables(text string, ctx *CompilerContext) string {
 	return result
 }
 
+// validateScriptFilePath checks that path is safe and resolves it within the project root.
+// It rejects absolute paths and path traversal (..).
+func validateScriptFilePath(projectRoot, path string) (string, error) {
+	if projectRoot == "" {
+		return "", fmt.Errorf("project root not set (internal error)")
+	}
+	if path == "" {
+		return "", fmt.Errorf("file path must not be empty")
+	}
+	if filepath.IsAbs(path) {
+		return "", fmt.Errorf("absolute paths are not allowed: %s", path)
+	}
+
+	// Reject path traversal components
+	cleaned := filepath.Clean(path)
+	for _, component := range strings.Split(cleaned, string(filepath.Separator)) {
+		if component == ".." {
+			return "", fmt.Errorf("path traversal is not allowed: %s", path)
+		}
+	}
+
+	// Resolve against project root
+	resolved := filepath.Join(projectRoot, cleaned)
+
+	// Verify containment within project root
+	projectRootWithSep := projectRoot + string(filepath.Separator)
+	if !strings.HasPrefix(resolved, projectRootWithSep) && resolved != projectRoot {
+		return "", fmt.Errorf("file access denied: path resolves outside project folder")
+	}
+
+	// Resolve symlinks to prevent symlink-based escape
+	realPath, err := filepath.EvalSymlinks(resolved)
+	if err == nil {
+		if !strings.HasPrefix(realPath, projectRootWithSep) && realPath != projectRoot {
+			return "", fmt.Errorf("file access denied: symlink target resolves outside project folder")
+		}
+		return realPath, nil
+	}
+
+	return resolved, nil
+}
+
+// makeLoadBinary creates a Starlark builtin function load_binary(path, offset?, length?)
+// that reads a binary file relative to the project root and returns a list of ints (0-255).
+func makeLoadBinary(projectRoot string) *starlark.Builtin {
+	return starlark.NewBuiltin("load_binary", func(thread *starlark.Thread, b *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+		var path string
+		var offset, length int
+		if err := starlark.UnpackPositionalArgs("load_binary", args, kwargs, 1, &path, &offset, &length); err != nil {
+			return nil, err
+		}
+
+		resolvedPath, err := validateScriptFilePath(projectRoot, path)
+		if err != nil {
+			return nil, fmt.Errorf("load_binary: %w", err)
+		}
+
+		data, err := os.ReadFile(resolvedPath)
+		if err != nil {
+			return nil, fmt.Errorf("load_binary: cannot read %s: %w", path, err)
+		}
+
+		if offset < 0 {
+			return nil, fmt.Errorf("load_binary: offset must be non-negative, got %d", offset)
+		}
+		if offset > len(data) {
+			return nil, fmt.Errorf("load_binary: offset %d exceeds file size %d", offset, len(data))
+		}
+		data = data[offset:]
+
+		if length > 0 {
+			if length > len(data) {
+				return nil, fmt.Errorf("load_binary: length %d exceeds available data %d", length, len(data))
+			}
+			data = data[:length]
+		}
+
+		result := make([]starlark.Value, len(data))
+		for i, b := range data {
+			result[i] = starlark.MakeInt(int(b))
+		}
+
+		return starlark.NewList(result), nil
+	})
+}
+
+// makeLoadText creates a Starlark builtin function load_text(path)
+// that reads a text file relative to the project root and returns a list of strings (lines).
+func makeLoadText(projectRoot string) *starlark.Builtin {
+	return starlark.NewBuiltin("load_text", func(thread *starlark.Thread, b *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+		var path string
+		if err := starlark.UnpackPositionalArgs("load_text", args, kwargs, 1, &path); err != nil {
+			return nil, err
+		}
+
+		resolvedPath, err := validateScriptFilePath(projectRoot, path)
+		if err != nil {
+			return nil, fmt.Errorf("load_text: %w", err)
+		}
+
+		data, err := os.ReadFile(resolvedPath)
+		if err != nil {
+			return nil, fmt.Errorf("load_text: cannot read %s: %w", path, err)
+		}
+
+		text := strings.ReplaceAll(string(data), "\r\n", "\n")
+		text = strings.TrimRight(text, "\n")
+
+		var lines []string
+		if text == "" {
+			lines = []string{}
+		} else {
+			lines = strings.Split(text, "\n")
+		}
+
+		result := make([]starlark.Value, len(lines))
+		for i, line := range lines {
+			result[i] = starlark.String(line)
+		}
+
+		return starlark.NewList(result), nil
+	})
+}
+
+// readScriptMaxSteps reads the _P_SCRIPT_MAX_STEPS pragma from the given pragma set.
+// Returns the configured value (must be > 0), or 1000000 as default.
+func readScriptMaxSteps(ctx *CompilerContext, pragmaSetIndex int) uint64 {
+	const defaultSteps uint64 = 1000000
+	ps := ctx.Pragma.GetPragmaSetByIndex(pragmaSetIndex)
+	v := ps.GetPragma("_P_SCRIPT_MAX_STEPS")
+	if v == "" {
+		return defaultSteps
+	}
+	n, err := strconv.ParseUint(v, 10, 64)
+	if err != nil || n == 0 {
+		return defaultSteps
+	}
+	return n
+}
+
 // ExecuteMacro executes a named macro with the given arguments and returns output lines
-func ExecuteMacro(macroName string, args []string, ctx *CompilerContext) ([]string, error) {
+// pragmaSetIndex is the index of the pragma set at the macro invocation call site.
+func ExecuteMacro(macroName string, args []string, ctx *CompilerContext, pragmaSetIndex int) ([]string, error) {
 	// Look up the macro
 	macro, ok := ctx.ScriptMacros[macroName]
 	if !ok {
@@ -130,6 +492,12 @@ func ExecuteMacro(macroName string, args []string, ctx *CompilerContext) ([]stri
 	}
 	finalScript += "_macro()\n"
 
+	// Use the source file where the macro was defined
+	starlarkFilename := macro.SourceFile
+	if starlarkFilename == "" {
+		starlarkFilename = "macro.star"
+	}
+
 	// Capture print output
 	var output bytes.Buffer
 	thread := &starlark.Thread{
@@ -139,12 +507,14 @@ func ExecuteMacro(macroName string, args []string, ctx *CompilerContext) ([]stri
 		},
 	}
 
-	// Set execution limit
-	thread.SetMaxExecutionSteps(1000000)
+	// Set execution limit from pragma at call site or default
+	thread.SetMaxExecutionSteps(readScriptMaxSteps(ctx, pragmaSetIndex))
 
-	// Build predeclared: math + library globals + parameter bindings
+	// Build predeclared: math + library globals + file I/O builtins + parameter bindings
 	predeclared := starlark.StringDict{
 		"math":        math.Module,
+		"load_binary": makeLoadBinary(ctx.ProjectRoot),
+		"load_text":   makeLoadText(ctx.ProjectRoot),
 	}
 	for k, v := range ctx.ScriptLibraryGlobals {
 		predeclared[k] = v
@@ -154,9 +524,19 @@ func ExecuteMacro(macroName string, args []string, ctx *CompilerContext) ([]stri
 	}
 
 	// Execute
-	_, err := starlark.ExecFile(thread, "macro.star", finalScript, predeclared)
+	_, err := starlark.ExecFile(thread, starlarkFilename, finalScript, predeclared)
 	if err != nil {
-		return nil, err
+		// Map error position back to macro definition site
+		starLine := starlarkPosition(err)
+		if starLine > 0 && macro.SourceFile != "" {
+			idx := mapStarlarkLine(starLine, len(macro.Body), false) // macro is always wrapped
+			if idx >= 0 {
+				sourceLine := macro.StartLine + idx
+				msg := starlarkErrorMsg(err)
+				return nil, fmt.Errorf("Starlark error: at %s:%d: %s", macro.SourceFile, sourceLine, msg)
+			}
+		}
+		return nil, fmt.Errorf("Starlark error: %w", err)
 	}
 
 	// Split output into lines

internal/preproc/preproc.go

@@ -170,7 +170,21 @@ func (p *preproc) run(root string) ([]Line, error) {
 				p.inScript = false
 				p.inScriptLibrary = false
 				p.inScriptMacro = false
-				continue // don't emit ENDSCRIPT marker
+				// Emit an empty Source line as a block boundary marker so the
+				// compiler can distinguish consecutive SCRIPT blocks via kind
+				// transitions. The compiler skips empty Source lines, so this
+				// serves purely as a transition trigger.
+				if includeSource {
+					out = append(out, Line{
+						RawText:        raw,
+						Text:           "",
+						Filename:       currFrame.path,
+						LineNo:         currFrame.line,
+						Kind:           Source,
+						PragmaSetIndex: p.pragma.GetCurrentPragmaSetIndex(),
+					})
+				}
+				continue
 			}
 			// Determine the kind based on which mode we're in
 			kind := Script

internal/preproc/preproc_test.go

@@ -151,9 +151,10 @@ func TestPreProcess_ScriptBlock(t *testing.T) {
 		t.Fatalf("PreProcess failed: %v", err)
 	}
 
-	// SCRIPT and ENDSCRIPT markers are stripped
-	if len(lines) != 3 {
-		t.Fatalf("expected 3 lines, got %d", len(lines))
+	// SCRIPT and ENDSCRIPT markers are stripped, but ENDSCRIPT emits
+	// an empty Source boundary marker
+	if len(lines) != 4 {
+		t.Fatalf("expected 4 lines, got %d", len(lines))
 	}
 
 	// Script content should NOT be processed
@@ -171,12 +172,20 @@ func TestPreProcess_ScriptBlock(t *testing.T) {
 		t.Errorf("expected Kind=Script, got %v", lines[1].Kind)
 	}
 
-	// After ENDSCRIPT, defines work again
-	if lines[2].Text != "LDA #100" {
-		t.Errorf("expected 'LDA #100', got %q", lines[2].Text)
-	}
+	// Line 2 is the ENDSCRIPT boundary marker (empty Source line)
 	if lines[2].Kind != Source {
-		t.Errorf("expected Kind=Source, got %v", lines[2].Kind)
+		t.Errorf("line 2: expected Kind=Source (ENDSCRIPT boundary), got %v", lines[2].Kind)
+	}
+	if lines[2].Text != "" {
+		t.Errorf("line 2: expected empty text, got %q", lines[2].Text)
+	}
+
+	// After ENDSCRIPT, defines work again
+	if lines[3].Text != "LDA #100" {
+		t.Errorf("expected 'LDA #100', got %q", lines[3].Text)
+	}
+	if lines[3].Kind != Source {
+		t.Errorf("expected Kind=Source, got %v", lines[3].Kind)
 	}
 }
 
@@ -262,8 +271,9 @@ func TestPreProcess_CommentInScriptBlock(t *testing.T) {
 		t.Fatalf("PreProcess failed: %v", err)
 	}
 
-	if len(lines) != 2 {
-		t.Fatalf("expected 2 lines, got %d", len(lines))
+	// 2 script lines + 1 ENDSCRIPT boundary marker + 0 trailing source = 3 lines
+	if len(lines) != 3 {
+		t.Fatalf("expected 3 lines, got %d", len(lines))
 	}
 
 	// Comments should be preserved in Script blocks
@@ -273,6 +283,11 @@ func TestPreProcess_CommentInScriptBlock(t *testing.T) {
 	if lines[1].Text != "  y = 2 // another one" {
 		t.Errorf("expected comment preserved, got %q", lines[1].Text)
 	}
+
+	// Line 2 is ENDSCRIPT boundary marker
+	if lines[2].Kind != Source || lines[2].Text != "" {
+		t.Errorf("line 2: expected empty Source (ENDSCRIPT boundary), got Kind=%v Text=%q", lines[2].Kind, lines[2].Text)
+	}
 }
 
 func TestPreProcess_RawTextPreservation(t *testing.T) {
@@ -883,6 +898,7 @@ func TestPreProcess_MixedBlocksAndComments(t *testing.T) {
 		{"LDA #10", Source},
 		{"  lda #X // asm comment", Assembler},
 		{"  y = X // script comment", Script},
+		{"", Source}, // ENDSCRIPT boundary marker
 		{"STA $D020", Source},
 	}
 
@@ -938,12 +954,17 @@ func TestPreProcess_EmptyScriptBlock(t *testing.T) {
 		t.Fatalf("PreProcess failed: %v", err)
 	}
 
-	if len(lines) != 1 {
-		t.Fatalf("expected 1 line, got %d", len(lines))
+	// Empty script emits an ENDSCRIPT boundary marker + NOP
+	if len(lines) != 2 {
+		t.Fatalf("expected 2 lines, got %d", len(lines))
 	}
 
-	if lines[0].Text != "NOP" {
-		t.Errorf("expected 'NOP', got %q", lines[0].Text)
+	if lines[0].Kind != Source || lines[0].Text != "" {
+		t.Errorf("line 0: expected empty Source (ENDSCRIPT boundary), got Kind=%v Text=%q", lines[0].Kind, lines[0].Text)
+	}
+
+	if lines[1].Text != "NOP" {
+		t.Errorf("expected 'NOP', got %q", lines[1].Text)
 	}
 }
 
@@ -963,9 +984,9 @@ func TestPreProcess_ScriptLibraryBlock(t *testing.T) {
 		t.Fatalf("PreProcess failed: %v", err)
 	}
 
-	// Should have 2 script lines + 1 source line
-	if len(lines) != 3 {
-		t.Fatalf("expected 3 lines, got %d", len(lines))
+	// Should have 2 script lines + 1 ENDSCRIPT boundary + 1 source line = 4 lines
+	if len(lines) != 4 {
+		t.Fatalf("expected 4 lines, got %d", len(lines))
 	}
 
 	// Script library lines should have ScriptLibrary kind
@@ -980,12 +1001,20 @@ func TestPreProcess_ScriptLibraryBlock(t *testing.T) {
 		t.Errorf("expected Kind=ScriptLibrary, got %v", lines[1].Kind)
 	}
 
-	// Source line after ENDSCRIPT
+	// Line 2 is the ENDSCRIPT boundary marker
 	if lines[2].Kind != Source {
-		t.Errorf("expected Kind=Source, got %v", lines[2].Kind)
+		t.Errorf("line 2: expected Kind=Source (ENDSCRIPT boundary), got %v", lines[2].Kind)
 	}
-	if lines[2].Text != "NOP" {
-		t.Errorf("expected 'NOP', got %q", lines[2].Text)
+	if lines[2].Text != "" {
+		t.Errorf("line 2: expected empty text, got %q", lines[2].Text)
+	}
+
+	// Source line after ENDSCRIPT
+	if lines[3].Kind != Source {
+		t.Errorf("expected Kind=Source, got %v", lines[3].Kind)
+	}
+	if lines[3].Text != "NOP" {
+		t.Errorf("expected 'NOP', got %q", lines[3].Text)
 	}
 }
 
@@ -1006,18 +1035,29 @@ func TestPreProcess_ScriptVsScriptLibrary(t *testing.T) {
 		t.Fatalf("PreProcess failed: %v", err)
 	}
 
-	if len(lines) != 2 {
-		t.Fatalf("expected 2 lines, got %d", len(lines))
+	// Two blocks → 1 lib line + 1 lib ENDSCRIPT boundary + 1 script line + 1 script ENDSCRIPT boundary = 4 lines
+	if len(lines) != 4 {
+		t.Fatalf("expected 4 lines, got %d", len(lines))
 	}
 
-	// First line is from SCRIPT LIBRARY
+	// Line 0: SCRIPT LIBRARY content
 	if lines[0].Kind != ScriptLibrary {
 		t.Errorf("line 0: expected ScriptLibrary, got %v", lines[0].Kind)
 	}
 
-	// Second line is from regular SCRIPT
-	if lines[1].Kind != Script {
-		t.Errorf("line 1: expected Script, got %v", lines[1].Kind)
+	// Line 1: ENDSCRIPT boundary for library
+	if lines[1].Kind != Source || lines[1].Text != "" {
+		t.Errorf("line 1: expected empty Source (ENDSCRIPT boundary), got Kind=%v Text=%q", lines[1].Kind, lines[1].Text)
+	}
+
+	// Line 2: regular SCRIPT content
+	if lines[2].Kind != Script {
+		t.Errorf("line 2: expected Script, got %v", lines[2].Kind)
+	}
+
+	// Line 3: ENDSCRIPT boundary for script
+	if lines[3].Kind != Source || lines[3].Text != "" {
+		t.Errorf("line 3: expected empty Source (ENDSCRIPT boundary), got Kind=%v Text=%q", lines[3].Kind, lines[3].Text)
 	}
 }
 
@@ -1036,9 +1076,9 @@ func TestPreProcess_ScriptMacroBlock(t *testing.T) {
 		t.Fatalf("PreProcess failed: %v", err)
 	}
 
-	// Should have header + body line + source line = 3 lines
-	if len(lines) != 3 {
-		t.Fatalf("expected 3 lines, got %d", len(lines))
+	// Should have header + body line + ENDSCRIPT boundary + source line = 4 lines
+	if len(lines) != 4 {
+		t.Fatalf("expected 4 lines, got %d", len(lines))
 	}
 
 	// First line is the header (also ScriptMacroDef kind)
@@ -1054,12 +1094,20 @@ func TestPreProcess_ScriptMacroBlock(t *testing.T) {
 		t.Errorf("line 1: expected ScriptMacroDef, got %v", lines[1].Kind)
 	}
 
-	// Third line is source
+	// Third line is ENDSCRIPT boundary marker
 	if lines[2].Kind != Source {
-		t.Errorf("line 2: expected Source, got %v", lines[2].Kind)
+		t.Errorf("line 2: expected Source (ENDSCRIPT boundary), got %v", lines[2].Kind)
 	}
-	if lines[2].Text != "NOP" {
-		t.Errorf("line 2: expected 'NOP', got %q", lines[2].Text)
+	if lines[2].Text != "" {
+		t.Errorf("line 2: expected empty text, got %q", lines[2].Text)
+	}
+
+	// Fourth line is source
+	if lines[3].Kind != Source {
+		t.Errorf("line 3: expected Source, got %v", lines[3].Kind)
+	}
+	if lines[3].Text != "NOP" {
+		t.Errorf("line 3: expected 'NOP', got %q", lines[3].Text)
 	}
 }
 

internal/utils/utils.go

@@ -102,6 +102,34 @@ func ToUpper(s string) string {
 	return strings.ToUpper(s)
 }
 
+// NormalizeCommas inserts spaces around commas outside quoted strings,
+// then collapses multiple spaces. This ensures commas are treated as
+// separate tokens when passed to ParseParams.
+func NormalizeCommas(s string) string {
+	var result strings.Builder
+	inString := false
+
+	for i := 0; i < len(s); i++ {
+		ch := s[i]
+
+		if ch == '"' {
+			inString = !inString
+			result.WriteByte(ch)
+			continue
+		}
+
+		if !inString && ch == ',' {
+			result.WriteByte(' ')
+			result.WriteByte(',')
+			result.WriteByte(' ')
+		} else {
+			result.WriteByte(ch)
+		}
+	}
+
+	return NormalizeSpaces(result.String())
+}
+
 // ValidateIdentifier checks if s is a valid identifier (starts with letter/underscore, continues with alphanumeric/underscore)
 func ValidateIdentifier(s string) bool {
 	if len(s) == 0 {

language.md

@@ -507,6 +507,58 @@ SCRIPT
 ENDSCRIPT
 ```
 
+#### File I/O
+
+Scripts can read binary and text files at compile time using `load_binary()` and `load_text()`. These functions only allow access to files within the project folder (where the main .c65 file resides) and its subdirectories. Absolute paths and path traversal (`..`) are rejected.
+
+**`load_binary(path, offset=0, length=0)`**
+
+Reads a binary file and returns a list of integers (0-255). The optional `offset` parameter skips bytes at the start, and `length` limits how many bytes to read (0 = read to end of file).
+
+```c65
+SCRIPT
+    sprite = load_binary("assets/hero.spr")
+    print("hero_sprite:")
+    for i in range(0, len(sprite), 8):
+        row = ", ".join(["$%02x" % b for b in sprite[i:i+8]])
+        print("  !byte " + row)
+ENDSCRIPT
+```
+
+**`load_text(path)`**
+
+Reads a text file and returns a list of strings, one per line. Handles both `\n` (Unix) and `\r\n` (Windows) line endings.
+
+```c65
+SCRIPT
+    level = load_text("levels/lvl1.txt")
+    print("level_map:")
+    for y in range(len(level)):
+        print("  !text " + repr(level[y]))
+ENDSCRIPT
+```
+
+**Example — resource loading with SCRIPT LIBRARY:**
+
+```c65
+SCRIPT LIBRARY
+    # Load resources into library globals
+    font_data = load_binary("assets/font.chr")
+    level = load_text("levels/lvl1.txt")
+
+    def emit_font():
+        print("font:")
+        for i in range(0, len(font_data), 8):
+            row = ", ".join(["$%02x" % b for b in font_data[i:i+8]])
+            print("  !byte " + row)
+
+    def emit_level():
+        print("level:")
+        for line in level:
+            print("  !text " + repr(line))
+ENDSCRIPT
+```
+
 ### SCRIPT LIBRARY Blocks
 
 Define reusable Starlark functions that persist across all subsequent SCRIPT blocks:

main.go

@@ -139,6 +139,15 @@ func compileOnly(inFile, outFile string, opt, optDebug, optC64 bool, optExcludes
 
 	// Create compiler and register commands
 	comp := compiler.NewCompiler(pragma)
+	absInput, err := filepath.Abs(inFile)
+	if err != nil {
+		return fmt.Errorf("failed to resolve input file path: %w", err)
+	}
+	projectRoot := filepath.Dir(absInput)
+	if canonicalRoot, err := filepath.EvalSymlinks(projectRoot); err == nil {
+		projectRoot = canonicalRoot
+	}
+	comp.Context().ProjectRoot = projectRoot
 	comp.CmdlineOpt = opt
 	comp.CmdlineDebug = optDebug
 	// Build I/O regions from CLI flags

opencode-config/opencode.json

@@ -12,6 +12,15 @@
     "build": {
       "model": "deepseek/deepseek-v4-flash",
       "description": "Implementation and coding using DeepSeek V4 Flash"
+    },
+    "build-pro": {
+      "model": "deepseek/deepseek-v4-pro",
+      "mode": "primary",
+      "options": {
+        "thinking": { "type": "enabled" },
+        "reasoningEffort": "high"
+      },
+      "description": "Implementation and coding using DeepSeek V4 Pro"
     }
   }
 }

syntax.md

@@ -394,9 +394,56 @@ ENDSCRIPT
 - Output from `print()` goes directly to assembler
 - Can reference compiler variables using `|varname|` syntax
 - Math module available: `import math`
-- Maximum 1 million execution steps (prevents infinite loops)
+- Maximum 1 million execution steps per block (prevents infinite loops). Each `SCRIPT`, `SCRIPT LIBRARY`, and `@macro()` invocation gets its own step counter. The limit is not cumulative across the compilation.
+- If a block exceeds the limit, compilation fails with: `Starlark computation cancelled: too many steps`
+- Use `#PRAGMA _P_SCRIPT_MAX_STEPS <n>` to change the limit (e.g., `#PRAGMA _P_SCRIPT_MAX_STEPS 5000000` for more steps, or `#PRAGMA _P_SCRIPT_MAX_STEPS 100` for a tight limit during debugging). The pragma is sticky — it applies to all subsequent blocks until changed.
 - Executed at compile time, not runtime
 
+**File I/O Built-in Functions:**
+
+Scripts can read files from the project folder (the directory containing the main input .c65 file) using the following built-in functions:
+
+- **`load_binary(path, offset=0, length=0)`** — Loads a binary file and returns a list of integers (0-255). Optional `offset` specifies a starting byte position, and `length` limits the number of bytes read (0 = read all remaining bytes).
+- **`load_text(path)`** — Loads a text file and returns a list of strings, one per line. Handles both `\n` and `\r\n` line endings.
+
+**Security restrictions:**
+- Only relative paths are allowed (no absolute paths like `/etc/passwd`)
+- Path traversal (`..`) is not permitted
+- Only files inside the project folder (or its subdirectories) can be accessed
+- File access errors cause a compile error with source location
+
+**Example — loading sprite data:**
+
+```
+SCRIPT
+    sprite = load_binary("assets/hero.spr")    # load binary data
+    print("hero_sprite:")
+    for i in range(0, len(sprite), 8):
+        row = ", ".join(["$%02x" % b for b in sprite[i:i+8]])
+        print("  !byte " + row)
+ENDSCRIPT
+```
+
+**Example — loading a level map:**
+
+```
+SCRIPT LIBRARY
+    # Load a text-based level map at compile time
+    level = load_text("levels/lvl1.txt")
+    height = len(level)
+    width = len(level[0]) if height > 0 else 0
+
+    def emit_map():
+        print("level_map:")
+        for y in range(height):
+            print("  !text " + repr(level[y]))
+        print("level_height:")
+        print("  !8 %d" % height)
+        print("level_width:")
+        print("  !8 %d" % width)
+ENDSCRIPT
+```
+
 ---
 
 ### SCRIPT LIBRARY...ENDSCRIPT