avoid impossible type casts

compiler/examples/test.p8

@@ -2,78 +2,68 @@
 %option enable_floats
 
 
-~ spritedata $0a00 {
-    ; this memory block contains the sprite data
-    ; it must start on an address aligned to 64 bytes.
-    %option force_output    ; make sure the data in this block appears in the resulting program
-
-    ubyte[63] balloonsprite = [ %00000000,%01111111,%00000000,
-                                %00000001,%11111111,%11000000,
-                                %00000011,%11111111,%11100000,
-                                %00000011,%11100011,%11100000,
-                                %00000111,%11011100,%11110000,
-                                %00000111,%11011101,%11110000,
-                                %00000111,%11011100,%11110000,
-                                %00000011,%11100011,%11100000,
-                                %00000011,%11111111,%11100000,
-                                %00000011,%11111111,%11100000,
-                                %00000010,%11111111,%10100000,
-                                %00000001,%01111111,%01000000,
-                                %00000001,%00111110,%01000000,
-                                %00000000,%10011100,%10000000,
-                                %00000000,%10011100,%10000000,
-                                %00000000,%01001001,%00000000,
-                                %00000000,%01001001,%00000000,
-                                %00000000,%00111110,%00000000,
-                                %00000000,%00111110,%00000000,
-                                %00000000,%00111110,%00000000,
-                                %00000000,%00011100,%00000000   ]
-}
-
 ~ main {
 
-    const uword SP0X = $d000
-    const uword SP0Y = $d001
-
     sub start() {
+        ubyte i=0
 
-        c64.STROUT("balloon sprites!\n")
-        c64.STROUT("...we are all floating...\n")
 
-        const uword sprite_address_ptr = $0a00 // 64
+        repeat {
-        c64.SPRPTR0 = sprite_address_ptr
+            c64scr.print_ub(X)
-        c64.SPRPTR1 = sprite_address_ptr
+            c64.CHROUT('\n')
-        c64.SPRPTR2 = sprite_address_ptr
+            ubyte ubx = fastsin8(i) as ubyte
-        c64.SPRPTR3 = sprite_address_ptr
+            c64scr.print_ub(X)
-        c64.SPRPTR4 = sprite_address_ptr
+            c64.CHROUT('\n')
-        c64.SPRPTR5 = sprite_address_ptr
+            ;c64scr.print_ub(X)
-        c64.SPRPTR6 = sprite_address_ptr
+            ;byte y = fastcos8(i)
-        c64.SPRPTR7 = sprite_address_ptr
+            c64scr.print_ub(ubx)
-
+            ;c64.CHROUT(',')
-        for ubyte i in 0 to 7 {
+            ;c64scr.print_b(y)
-            @(SP0X+i*2) = 50+25*i
+            c64.CHROUT('\n')
-            @(SP0Y+i*2) = rnd()
+            i++
-        }
+        } until i==0
-
-        c64.SPENA = 255                ; enable all sprites
-        c64utils.set_rasterirq(51)     ; enable animation
-    }
     }
 
 
-~ irq {
+asmsub fastsin8(ubyte angle8 @ Y) -> clobbers() -> (byte @ A)  {
-sub irq() {
+    %asm {{
-    c64.EXTCOL--
+        lda  sinecos8hi,y
-    ; float up & wobble horizontally
+        ;sta  prog8_lib.ESTACK_LO,x
-    for ubyte i in 0 to 14 step 2 {
+        ;dex
-        @(main.SP0Y+i)--
+        rts
-        ubyte r = rnd()
+    }}
-        if r>200
-            @(main.SP0X+i)++
-        else if r<40
-            @(main.SP0X+i)--
-    }
-    c64.EXTCOL++
 }
 
+asmsub fastcos8(ubyte angle8 @ Y) -> clobbers() -> (byte @ A)  {
+    %asm {{
+        lda  sinecos8hi+64,y
+        rts
+    }}
+}
+asmsub fastsin16(ubyte angle8 @ Y) -> clobbers() -> (word @ AY)  {
+    %asm {{
+        lda  sinecos8lo,y
+        pha
+        lda  sinecos8hi,y
+        tay
+        pla
+        rts
+    }}
+}
+asmsub fastcos16(ubyte angle8 @ Y) -> clobbers() -> (word @ AY)  {
+    %asm {{
+        lda  sinecos8lo+64,y
+        pha
+        lda  sinecos8hi+64,y
+        tay
+        pla
+        rts
+    }}
+}
+    %asm {{
+_  :=  32767.5 * sin(range(256+64) * rad(360.0/256.0))
+sinecos8lo     .byte <_
+sinecos8hi     .byte >_
+
+    }}
 }

compiler/src/prog8/ast/AstChecker.kt

@@ -712,6 +712,14 @@ class AstChecker(private val namespace: INameScope,
         return super.process(expr)
     }
 
+    override fun process(typecast: TypecastExpression): IExpression {
+        val funcTarget = (typecast.expression as? IFunctionCall)?.target?.targetStatement(namespace)
+        if(funcTarget is Subroutine && funcTarget.asmReturnvaluesRegisters.isNotEmpty()) {
+            checkResult.add(ExpressionError("cannot type cast a call to an asmsub that returns value in register - use a variable to store it first", typecast.position))
+        }
+        return super.process(typecast)
+    }
+
     override fun process(range: RangeExpr): IExpression {
         fun err(msg: String) {
             checkResult.add(SyntaxError(msg, range.position))

compiler/src/prog8/compiler/Compiler.kt

@@ -2044,6 +2044,11 @@ private class StatementTranslator(private val prog: IntermediateProgram,
     }
 
     private fun translate(expr: TypecastExpression) {
+        val funcTarget = (expr.expression as? IFunctionCall)?.target?.targetStatement(namespace)
+        if(funcTarget is Subroutine && funcTarget.asmReturnvaluesRegisters.isNotEmpty()) {
+            throw CompilerException("cannot type cast a call to an asmsub that returns value in register - use a variable to store it first")
+        }
+
         translate(expr.expression)
         val sourceDt = expr.expression.resultingDatatype(namespace, heap) ?: throw CompilerException("don't know what type to cast")
         if(sourceDt==expr.type)

compiler/src/prog8/compiler/intermediate/IntermediateProgram.kt

@@ -337,13 +337,20 @@ class IntermediateProgram(val name: String, var loadAddress: Int, val heap: Heap
                 }
                 currentBlock.variables[scopedname] = value
             }
-            VarDeclType.MEMORY, VarDeclType.CONST -> {
+            VarDeclType.MEMORY -> {
                 // note that constants are all folded away, but assembly code may still refer to them
                 val lv = decl.value as LiteralValue
                 if(lv.type!=DataType.UWORD && lv.type!=DataType.UBYTE)
                     throw CompilerException("expected integer memory address $lv")
                 currentBlock.memoryPointers[scopedname] = Pair(lv.asIntegerValue!!, decl.datatype)
             }
+            VarDeclType.CONST -> {
+                // note that constants are all folded away, but assembly code may still refer to them (if their integers)
+                // floating point constants are not generated at all!!
+                val lv = decl.value as LiteralValue
+                if(lv.type in IntegerDatatypes)
+                    currentBlock.memoryPointers[scopedname] = Pair(lv.asIntegerValue!!, decl.datatype)
+            }
         }
     }
 

prog8lib/c64utils.p8

@@ -530,6 +530,8 @@ _raster_irq_handler
 	; ---- this block contains C-64 floating point related functions ----
 	; @todo move to c64fp.p8  and enable float-checkin astchecker.process(decl: VarDecl) again
 	
+	const float PI = 3.141592653589793
+
 
 asmsub  FREADS32  () -> clobbers(A,X,Y) -> ()  {
 	; ---- fac1 = signed int32 from $62-$65 big endian (MSB FIRST)