From 2ceaa25181c865cd0b44ba45ef978b74a74ab6df Mon Sep 17 00:00:00 2001
From: Irmen de Jong <irmen@razorvine.net>
Date: Sun, 29 Oct 2023 23:41:34 +0100
Subject: [PATCH] optimized code for (infrequently used) logical operations on
 word array

---
 .../assignment/AugmentableAssignmentAsmGen.kt | 72 +++++++++++++++++--
 examples/test.p8                              | 22 ++++--
 2 files changed, 86 insertions(+), 8 deletions(-)

diff --git a/codeGenCpu6502/src/prog8/codegen/cpu6502/assignment/AugmentableAssignmentAsmGen.kt b/codeGenCpu6502/src/prog8/codegen/cpu6502/assignment/AugmentableAssignmentAsmGen.kt
index fbeadb3cc..c0bfed34a 100644
--- a/codeGenCpu6502/src/prog8/codegen/cpu6502/assignment/AugmentableAssignmentAsmGen.kt
+++ b/codeGenCpu6502/src/prog8/codegen/cpu6502/assignment/AugmentableAssignmentAsmGen.kt
@@ -457,7 +457,6 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
     }
 
     private fun inplacemodificationRegisterAXwithVariable(operator: String, variable: String, varDt: DataType): Boolean {
-        // note: we only optimize addition and subtraction, and these are the same for unsigned or signed.
         when(operator) {
             "+" -> {
                 return if(varDt in WordDatatypes) {
@@ -507,12 +506,44 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                     true
                 }
             }
-            else -> return false        // TODO optimize more operators, such as the bitwise logical ones? Might need to know if signed
+            "|" -> {
+                asmgen.out("""
+                    ora  $variable
+                    tay
+                    txa
+                    ora  $variable+1
+                    tax
+                    tya
+                """)
+                return true
+            }
+            "&" -> {
+                asmgen.out("""
+                    and  $variable
+                    tay
+                    txa
+                    and  $variable+1
+                    tax
+                    tya
+                """)
+                return true
+            }
+            "^" -> {
+                asmgen.out("""
+                    eor  $variable
+                    tay
+                    txa
+                    eor  $variable+1
+                    tax
+                    tya
+                """)
+                return true
+            }
+            else -> return false
         }
     }
 
     private fun inplacemodificationRegisterAXwithLiteralval(operator: String, number: Int): Boolean {
-        // note: we only optimize addition and subtraction, and these are the same for unsigned or signed.
         when(operator) {
             "+" -> {
                 return if(number in -128..255) {
@@ -556,7 +587,40 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                     true
                 }
             }
-            else -> return false        // TODO optimize more operators, such as the bitwise logical ones? Might need to know if signed
+            "|" -> {
+                asmgen.out("""
+                    ora  #<$number
+                    tay
+                    txa
+                    ora  #>$number
+                    tax
+                    tya
+                """)
+                return true
+            }
+            "&" -> {
+                asmgen.out("""
+                    and  #<$number
+                    tay
+                    txa
+                    and  #>$number
+                    tax
+                    tya
+                """)
+                return true
+            }
+            "^" -> {
+                asmgen.out("""
+                    eor  #<$number
+                    tay
+                    txa
+                    eor  #>$number
+                    tax
+                    tya
+                """)
+                return true
+            }
+            else -> return false
         }
     }
 
diff --git a/examples/test.p8 b/examples/test.p8
index b9f18a3c6..39318bd5d 100644
--- a/examples/test.p8
+++ b/examples/test.p8
@@ -5,10 +5,24 @@
 
 main {
     sub start() {
-        ubyte lower = 123
-        ubyte upper = 0
-        uword ww = mkword(upper, lower)
+        uword[] array = [$1010,$2020,$3030,$4040,$5050]
+        ubyte index = 2
+        uword value = $0205
 
-        txt.print_uwhex(ww, true)
+        array[index] ^= $0205
+        txt.print_uwhex(array[2], true)
+        txt.nl()
+
+        array[index]+=9
+
+        txt.print_uwhex(array[2], true)
+        txt.nl()
+
+        array[index] = $3030
+        array[index] |= value
+        txt.print_uwhex(array[2], true)
+        txt.nl()
+
+        ; TODO met var array[index]|=index
     }
 }