slight tweak to word bitshift for large shift values

compiler/src/prog8/compiler/target/c64/codegen/ExpressionsAsmGen.kt

@@ -1642,6 +1642,13 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                             }
                         }
                         DataType.UWORD -> {
+                            if(amount>=16) {
+                                if(CompilationTarget.instance.machine.cpu==CpuType.CPU65c02)
+                                    asmgen.out("  stz  P8ESTACK_LO+1,x |  stz  P8ESTACK_HI+1,x")
+                                else
+                                    asmgen.out("  lda  #0 |  sta  P8ESTACK_LO+1,x |  sta  P8ESTACK_HI+1,x")
+                                return
+                            }
                             var left = amount
                             while (left >= 7) {
                                 asmgen.out(" jsr  math.shift_right_uw_7")
@@ -1653,6 +1660,20 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                                 asmgen.out(" jsr  math.shift_right_uw_$left")
                         }
                         DataType.WORD -> {
+                            if(amount>=16) {
+                                asmgen.out("""
+                                    lda  P8ESTACK_HI+1,x
+                                    bmi  +
+                                    lda  #0
+                                    sta  P8ESTACK_LO+1,x
+                                    sta  P8ESTACK_HI+1,x
+                                    beq  ++
++                                   lda  #255
+                                    sta  P8ESTACK_LO+1,x
+                                    sta  P8ESTACK_HI+1,x
++""")
+                                return
+                            }
                             var left = amount
                             while (left >= 7) {
                                 asmgen.out(" jsr  math.shift_right_w_7")

examples/test.p8

@@ -6,154 +6,6 @@
 main {
 
     sub start() {
-        uword uw
-        uword xx
-        word ww
-        word yy
-
-        uw = shiftruw7()
-        xx+=uw
-        uw = shiftruw8()
-        xx+=uw
-        uw = shiftruw9()
-        xx+=uw
-        uw = shiftruw10()
-        xx+=uw
-        uw = shiftruw11()
-        xx+=uw
-        uw = shiftruw12()
-        xx+=uw
-        uw = shiftruw13()
-        xx+=uw
-        uw = shiftruw14()
-        xx+=uw
-        uw = shiftruw15()
-        xx+=uw
-
-        ww = shiftrsw7()
-        yy+=ww
-        ww = shiftrsw8()
-        yy+=ww
-        ww = shiftrsw9()
-        yy+=ww
-        ww = shiftrsw10()
-        yy+=ww
-        ww = shiftrsw11()
-        yy+=ww
-        ww = shiftrsw12()
-        yy+=ww
-        ww = shiftrsw13()
-        yy+=ww
-        ww = shiftrsw14()
-        yy+=ww
-        ww = shiftrsw15()
-        yy+=ww
-        ww = shiftrsw16()       ; TODO why sub not replaced by const?
-        yy+=ww
-        ww = shiftrsw17()       ; TODO why sub not replaced by const?
-        yy+=ww
-
-    }
-
-
-        sub shiftruw7() -> uword {
-            uword q = $a49f
-            return q >> 7
-        }
-
-        sub shiftruw8() -> uword {
-            uword q = $a49f
-            return (q >> 8)         ; TODO fix slow?  (and for all below)
-        }
-
-        sub shiftruw9() -> uword {
-            uword q = $a49f
-            return (q >> 9)
-        }
-
-        sub shiftruw10() -> uword {
-            uword q = $a49f
-            return (q >> 10)
-        }
-
-        sub shiftruw11() -> uword {
-            uword q = $a49f
-            return (q >> 11)
-        }
-
-        sub shiftruw12() -> uword {
-            uword q = $a49f
-            return (q >> 12)
-        }
-
-        sub shiftruw13() -> uword {
-            uword q = $a49f
-            return (q >> 13)
-        }
-
-        sub shiftruw14() -> uword {
-            uword q = $a49f
-            return (q >> 14)
-        }
-
-        sub shiftruw15() -> uword {
-            uword q = $a49f
-            return (q >> 15)
-        }
-
-    sub shiftrsw7() -> word {
-        word q = -12345
-        return q >> 7
-    }
-
-    sub shiftrsw8() -> word {
-        word q = -12345
-        return (q >> 8)         ; TODO why not marked slow?  What code is generated?  Also for all below.
-    }
-
-    sub shiftrsw9() -> word {
-        word q = -12345
-        return (q >> 9)
-    }
-
-    sub shiftrsw10() -> word {
-        word q = -12345
-        return (q >> 10)
-    }
-
-    sub shiftrsw11() -> word {
-        word q = -12345
-        return (q >> 11)
-    }
-
-    sub shiftrsw12() -> word {
-        word q = -12345
-        return (q >> 12)
-    }
-
-    sub shiftrsw13() -> word {
-        word q = -12345
-        return (q >> 13)
-    }
-
-    sub shiftrsw14() -> word {
-        word q = -12345
-        return (q >> 14)
-    }
-
-    sub shiftrsw15() -> word {
-        word q = -12345
-        return (q >> 15)
-    }
-
-    sub shiftrsw16() -> word {
-        word q = -12345
-        return (q >> 16)
-    }
-
-    sub shiftrsw17() -> word {
-        word q = -12345
-        return (q >> 17)
     }
 
 }