optimize simple word and byte addition/subtraction better

codeGenCpu6502/src/prog8/codegen/cpu6502/assignment/AssignmentAsmGen.kt

@@ -1108,10 +1108,17 @@ internal class AssignmentAsmGen(private val program: PtProgram,
                 }
                 is PtNumber -> {
                     assignExpressionToRegister(left, RegisterOrPair.A, dt==DataType.BYTE)
+                    if(right.number==1.0 && asmgen.isTargetCpu(CpuType.CPU65c02)) {
+                        if (expr.operator == "+")
+                            asmgen.out("  inc  a")
+                        else
+                            asmgen.out("  dec  a")
+                    } else {
                         if (expr.operator == "+")
                             asmgen.out("  clc |  adc  #${right.number.toHex()}")
                         else
                             asmgen.out("  sec |  sbc  #${right.number.toHex()}")
+                    }
                     assignRegisterByte(target, CpuRegister.A, dt in SignedDatatypes, true)
                     return true
                 }
@@ -1246,6 +1253,37 @@ internal class AssignmentAsmGen(private val program: PtProgram,
                 }
                 is PtNumber -> {
                     assignExpressionToRegister(left, RegisterOrPair.AY, dt==DataType.WORD)
+                    if(right.number==1.0 && asmgen.isTargetCpu(CpuType.CPU65c02)) {
+                        if(expr.operator=="+") {
+                            asmgen.out("""
+                                inc  a
+                                bne  +
+                                iny
++""")
+                        } else {
+                            asmgen.out("""
+                                dec  a
+                                cmp  #255
+                                bne  +
+                                dey
++""")
+                        }
+                    } else if(dt!=DataType.WORD && right.number.toInt() in 0..255) {
+                        if(expr.operator=="+") {
+                            asmgen.out("""
+                                clc
+                                adc  #${right.number.toHex()}
+                                bcc  +
+                                iny
++""")                   } else if(expr.operator=="-") {
+                            asmgen.out("""
+                                sec
+                                sbc  #${right.number.toHex()}
+                                bcs  +
+                                dey
++""")
+                        }
+                    } else {
                         if(expr.operator=="+") {
                             asmgen.out("""
                                 clc
@@ -1265,6 +1303,7 @@ internal class AssignmentAsmGen(private val program: PtProgram,
                                 tay
                                 txa""")
                         }
+                    }
                     assignRegisterpairWord(target, RegisterOrPair.AY)
                     return true
                 }

docs/source/todo.rst

@@ -6,8 +6,6 @@ causes compiler error for virtual: just calling txt.cls() gives compile error un
 
 https://github.com/irmen/prog8/issues/136 (string.find register order issue)
 
-optimization: for 65c02 sometimes clc adc #1 is generated (for instance for:  cx16.r0L = math.sin8u(cx16.r0L+1)), this can be optimized into inc a (always? or not? mind the carry flag!)
-
 optimization: for 65c02 sometimes tya pha is generated, could be just phy (mind if A gets used afterwards though!) (same for pla tay etcetera?)
 
 if-optimization:

examples/cx16/testmonogfx.p8

@@ -9,12 +9,12 @@
 main {
 
     sub start() {
-;        monogfx.lores()
+        monogfx.lores()
-;        demofill()
+        demofill()
-;        sys.wait(2*60)
+        sys.wait(2*60)
-;        monogfx.hires()
+        monogfx.hires()
-;        demo1()
+        demo1()
-;        sys.wait(2*60)
+        sys.wait(2*60)
         demo2()
 
         monogfx.textmode()

examples/test.p8

@@ -1,52 +1,133 @@
+%import math
 %import textio
 %zeropage basicsafe
-%option no_sysinit
 
 main {
     sub start() {
-        signed()
+        cx16.r0sL = 127
-        unsigned()
+        cx16.r0sL = bytefunc(cx16.r0sL+1)
+        cx16.r0sL = 0
+        cx16.r0sL = bytefunc(cx16.r0sL-1)
+        cx16.r0sL = 55
+        cx16.r0sL = bytefunc(cx16.r0sL+20)
+        cx16.r0sL = 55
+        cx16.r0sL = bytefunc(cx16.r0sL-20)
+
+        cx16.r0s = $99ff as word
+        cx16.r0s = wordfunc(cx16.r0s+1)
+        cx16.r0s = $9900 as word
+        cx16.r0s = wordfunc(cx16.r0s-1)
+        cx16.r0s = -12345
+        cx16.r0s = wordfunc(cx16.r0s+100)
+        cx16.r0s = -12345
+        cx16.r0s = wordfunc(cx16.r0s-100)
     }
 
-    sub signed() {
-        byte @shared bvalue = -100
-        word @shared wvalue = -20000
 
-        bvalue /= 2     ; TODO should be a simple bit shift?
+    sub bytefunc(byte x) -> byte {
-        wvalue /= 2     ; TODO should be a simple bit shift?
+        txt.print_ubhex(x as ubyte, true)
-
+        txt.spc()
-        txt.print_b(bvalue)
+        txt.print_b(x)
-        txt.nl()
-        txt.print_w(wvalue)
-        txt.nl()
-
-        bvalue *= 2
-        wvalue *= 2
-
-        txt.print_b(bvalue)
-        txt.nl()
-        txt.print_w(wvalue)
         txt.nl()
+        return x
     }
 
-    sub unsigned() {
+    sub wordfunc(word x) -> word {
-        ubyte @shared ubvalue = 100
+        txt.print_uwhex(x as uword, true)
-        uword @shared uwvalue = 20000
+        txt.spc()
-
+        txt.print_w(x)
-        ubvalue /= 2
-        uwvalue /= 2
-
-        txt.print_ub(ubvalue)
-        txt.nl()
-        txt.print_uw(uwvalue)
-        txt.nl()
-
-        ubvalue *= 2
-        uwvalue *= 2
-
-        txt.print_ub(ubvalue)
-        txt.nl()
-        txt.print_uw(uwvalue)
         txt.nl()
+        return x
     }
 }
+
+;%import math
+;%import sprites
+;
+;main {
+;    word[128] @split xpos_orig
+;    word[128] @split ypos_orig
+;    word[128] xpos
+;    word[128] ypos
+;    ubyte[128] tt
+;
+;    sub start() {
+;        cx16.mouse_config2(1)
+;        sprites.set_mousepointer_hand()
+;        ubyte sprdat_bank
+;        uword sprdat_addr
+;        sprdat_bank, sprdat_addr = sprites.get_data_ptr(0)
+;
+;        ubyte sprite
+;        for sprite in 0 to 127 {
+;            sprites.init(sprite, sprdat_bank, sprdat_addr, sprites.SIZE_16, sprites.SIZE_16, sprites.COLORS_256, 0)
+;            xpos_orig[sprite] = sprite*$0003 +100 as word
+;            ypos_orig[sprite] = sprite*$0002 +100 as word
+;            tt[sprite] = math.rnd()
+;        }
+;
+;        repeat {
+;            sys.waitvsync()
+;            sprites.pos_batch(0, 128, &xpos, &ypos)
+;            for sprite in 0 to 127 {
+;                tt[sprite]++
+;                xpos[sprite] = xpos_orig[sprite] + math.sin8(tt[sprite])
+;                ypos[sprite] = ypos_orig[sprite] + math.cos8(tt[sprite])
+;            }
+;        }
+;    }
+;}
+;
+;
+;;%import textio
+;;%zeropage basicsafe
+;;%option no_sysinit
+;;
+;;main {
+;;    sub start() {
+;;        signed()
+;;        unsigned()
+;;    }
+;;
+;;    sub signed() {
+;;        byte @shared bvalue = -100
+;;        word @shared wvalue = -20000
+;;
+;;        bvalue /= 2     ; TODO should be a simple bit shift?
+;;        wvalue /= 2     ; TODO should be a simple bit shift?
+;;
+;;        txt.print_b(bvalue)
+;;        txt.nl()
+;;        txt.print_w(wvalue)
+;;        txt.nl()
+;;
+;;        bvalue *= 2
+;;        wvalue *= 2
+;;
+;;        txt.print_b(bvalue)
+;;        txt.nl()
+;;        txt.print_w(wvalue)
+;;        txt.nl()
+;;    }
+;;
+;;    sub unsigned() {
+;;        ubyte @shared ubvalue = 100
+;;        uword @shared uwvalue = 20000
+;;
+;;        ubvalue /= 2
+;;        uwvalue /= 2
+;;
+;;        txt.print_ub(ubvalue)
+;;        txt.nl()
+;;        txt.print_uw(uwvalue)
+;;        txt.nl()
+;;
+;;        ubvalue *= 2
+;;        uwvalue *= 2
+;;
+;;        txt.print_ub(ubvalue)
+;;        txt.nl()
+;;        txt.print_uw(uwvalue)
+;;        txt.nl()
+;;    }
+;;}