From 10145b946b36ccdaa6a8971c4839240146e451d4 Mon Sep 17 00:00:00 2001
From: Irmen de Jong <irmen@razorvine.net>
Date: Tue, 13 Oct 2020 16:27:40 +0200
Subject: [PATCH] invalid repeat loop code is generated...

---
 .../compiler/target/c64/codegen/AsmGen.kt     |  3 ++
 examples/test.p8                              | 46 ++++++++++++++++++-
 2 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/compiler/src/prog8/compiler/target/c64/codegen/AsmGen.kt b/compiler/src/prog8/compiler/target/c64/codegen/AsmGen.kt
index 93d4db5f0..0dc5a18c9 100644
--- a/compiler/src/prog8/compiler/target/c64/codegen/AsmGen.kt
+++ b/compiler/src/prog8/compiler/target/c64/codegen/AsmGen.kt
@@ -938,6 +938,7 @@ internal class AsmGen(private val program: Program,
                 when {
                     iterations == 0 -> {}
                     iterations <= 256 -> {
+                        // TODO faulty loop code when 256 because of the beq that's also generated (should be ok if that is removed?)
                         out("  lda  #${iterations and 255}")
                         repeatByteCountInA(iterations, repeatLabel, endLabel, stmt.body)
                     }
@@ -985,6 +986,7 @@ internal class AsmGen(private val program: Program,
     private fun repeatWordCountInAY(constIterations: Int?, repeatLabel: String, endLabel: String, body: AnonymousScope) {
         // note: A/Y must have been loaded with the number of iterations already!
         val counterVar = makeLabel("repeatcounter")
+        // TODO the 0.w check at the start is invalid(wrong register check order), and must not be done at all if the loop count is numeric literal >0
         out("""
                 bne  +
                 cpy  #0
@@ -1018,6 +1020,7 @@ $counterVar    .word  0""")
     private fun repeatByteCountInA(constIterations: Int?, repeatLabel: String, endLabel: String, body: AnonymousScope) {
         // note: A must have been loaded with the number of iterations already!
         val counterVar = makeLabel("repeatcounter")
+        // TODO the beq endlabel check can be omitted if the number of iterations is a numeric literal >0
         out("""
             beq  $endLabel
             sta  $counterVar
diff --git a/examples/test.p8 b/examples/test.p8
index 9880b7d89..b26920b88 100644
--- a/examples/test.p8
+++ b/examples/test.p8
@@ -7,8 +7,50 @@
 main {
 
     sub start() {
-        derp()
-        rec2()
+        ubyte xx = 0
+        repeat 254 {
+            txt.chrout('1')
+            xx++
+        }
+        txt.print_ub(xx)
+        txt.chrout('\n')
+
+        xx=0
+
+        repeat 255 {
+            txt.chrout('2')
+            xx++
+        }
+        txt.print_ub(xx)
+        txt.chrout('\n')
+
+        xx=0
+        repeat 256 {                ; TODO generates faulty code, loop is never executed at all
+            txt.chrout('3')
+            xx++
+        }
+        txt.print_ub(xx)
+        txt.chrout('\n')
+
+        xx=0
+        repeat 257 {            ; TODO generates invalid 0-check code at start
+            txt.chrout('4')
+            xx++
+        }
+        txt.print_ub(xx)
+        txt.chrout('\n')
+
+        ubyte bb
+
+        repeat bb {
+            xx++
+        }
+
+        uword ww
+
+        repeat ww {
+            xx++
+        }
     }
 
     sub rec2() {