From e1b3582f0886de8069e3d620a0f41395383352ab Mon Sep 17 00:00:00 2001
From: Irmen de Jong <irmen@razorvine.net>
Date: Sun, 3 Sep 2023 01:12:26 +0200
Subject: [PATCH] fix wordvar -= @(memory)

---
 .../assignment/AugmentableAssignmentAsmGen.kt |  6 ++--
 examples/test.p8                              | 28 +++++++++----------
 2 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/codeGenCpu6502/src/prog8/codegen/cpu6502/assignment/AugmentableAssignmentAsmGen.kt b/codeGenCpu6502/src/prog8/codegen/cpu6502/assignment/AugmentableAssignmentAsmGen.kt
index 9389d205c..c4db483cc 100644
--- a/codeGenCpu6502/src/prog8/codegen/cpu6502/assignment/AugmentableAssignmentAsmGen.kt
+++ b/codeGenCpu6502/src/prog8/codegen/cpu6502/assignment/AugmentableAssignmentAsmGen.kt
@@ -892,7 +892,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
         // now implement the non-assiciative operators...
         when (operator) {
             "-" -> {
-                // TODO optimize: don't use scratch var
+                // A = variable - A
                 val tmpVar = if(variable!="P8ZP_SCRATCH_B1") "P8ZP_SCRATCH_B1" else "P8ZP_SCRATCH_REG"
                 asmgen.out("  sta  $tmpVar |  lda  $variable |  sec |  sbc  $tmpVar")
             }
@@ -1240,8 +1240,8 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
 +""")
             }
             "-" -> {
+                // name -= @(memory)
                 asmgen.translateDirectMemReadExpressionToRegA(memread)
-                // TODO optimize: don't use scratch var if possible
                 val tmpByte = if(name!="P8ZP_SCRATCH_B1") "P8ZP_SCRATCH_B1" else "P8ZP_SCRATCH_REG"
                 asmgen.out("""
                     sta  $tmpByte
@@ -1249,7 +1249,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                     sec
                     sbc  $tmpByte
                     sta  $name
-                    bcc  +
+                    bcs  +
                     dec  $name+1
 +""")
             }
diff --git a/examples/test.p8 b/examples/test.p8
index 0d728d72b..e1e274e1b 100644
--- a/examples/test.p8
+++ b/examples/test.p8
@@ -3,25 +3,25 @@
 
 main {
     sub start() {
-        byte index = 100
-        byte[] t_index = [-1,-2,-3,-4,-5]
 
-        index = 4
-        index = index>t_index[4]
-        txt.print_b(index)
-        txt.nl()
-        index = index>t_index[4]
-        txt.print_b(index)
-        txt.nl()
+        uword ww= 300
+        @($4000) = 100
+        ww -= @($4000)
+        ww -= 100
+        txt.print_uw(ww)        ; 100
 
-;        index = index < t_index[4]
-;        index = index < t_index[nibble]
-;        txt.print_ub(index)
+;        ubyte index = 100
+;        ubyte[] t_index = [1,2,3,4,5]
+;        ubyte nibble = 0
+;
+;        index = index + t_index[4]
+;        index = index + t_index[nibble]
+;        txt.print_ub(index)     ; 106
 ;        txt.nl()
 ;
 ;        nibble++
-;        index = index > t_index[3]
-;        index = index > t_index[nibble]
+;        index = index - t_index[3]
+;        index = index - t_index[nibble]
 ;        txt.print_ub(index)     ; 100
 ;        txt.nl()
     }