more ifexpression codegen tweaks

codeGenCpu6502/src/prog8/codegen/cpu6502/IfElseAsmGen.kt

@@ -417,6 +417,33 @@ internal class IfElseAsmGen(private val program: PtProgram,
             }
         }
 
+        if(constValue!=0) {
+            // TODO reuse more code from regular if statements. Need a shared routine like isWordExprEqualNumber() ?
+            when(condition.operator) {
+                "==" -> {
+                    // if w==number
+                    asmgen.assignExpressionToRegister(condition.left, RegisterOrPair.AY, signed)
+                    asmgen.out("""
+                        cmp  #<$constValue
+                        bne  $falseLabel
+                        cpy  #>$constValue
+                        bne  $falseLabel""")
+                    return
+                }
+                "!=" -> {
+                    // if w!=number
+                    asmgen.assignExpressionToRegister(condition.left, RegisterOrPair.AY, signed)
+                    asmgen.out("""
+                        cmp  #<$constValue
+                        bne  +
+                        cpy  #>$constValue
+                        beq  $falseLabel
++""")
+                    return
+                }
+            }
+        }
+
         // TODO don't store condition as expression result but just use the flags, like a normal PtIfElse translation does
         assignConditionValueToRegisterAndTest(condition)
         asmgen.out("  beq  $falseLabel")

compiler/res/prog8lib/cx16/bmx.p8

@@ -1,4 +1,5 @@
 ; Routines to load and save "BMX" files (commander X16 bitmap format) Version 1.
+; Bitmap data is loaded directly into VRAM without intermediary buffering.
 ; Only uncompressed images are supported for now.
 ; BMX Specification: https://cx16forum.com/forum/viewtopic.php?t=6945
 

examples/test.p8

@@ -5,21 +5,19 @@
 
 main {
     sub start() {
-        byte @shared ww = -99
-        ww++
-
-        if ww&1 ==0
-            txt.print("x ")
-
-        if ww&64 ==0
-            txt.print("a ")
-
-        if ww&128!=0
-            txt.print("neg ")
-
-        txt.print_ub(if ww & 64==0  111 else 222)
-        txt.spc()
-        txt.print_ub(if ww & 128!=0  111 else 222)
+        word @shared ww = 11111
+        txt.print_ub(if ww==11111  111 else 222)
         txt.spc()
+        txt.print_ub(if ww!=11111  111 else 222)
+        txt.nl()
+
+        if ww==11111
+            txt.print("one\n")
+        else
+            txt.print("two\n")
+        if ww!=11111
+            txt.print("one\n")
+        else
+            txt.print("two\n")
     }
 }