From 8f9d1cfa3087a47777e78d014717f4fdc1e44143 Mon Sep 17 00:00:00 2001
From: Irmen de Jong <irmen@razorvine.net>
Date: Mon, 24 Oct 2022 23:43:47 +0200
Subject: [PATCH] fix regression: indexing pointer variable with word (>255)
 didn't work anymore since release 8.2 or so

---
 .../compiler/astprocessing/CodeDesugarer.kt   | 28 +++++++++++++++++++
 compiler/test/ast/TestVarious.kt              | 18 +++++++++++-
 docs/source/todo.rst                          |  2 ++
 3 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/compiler/src/prog8/compiler/astprocessing/CodeDesugarer.kt b/compiler/src/prog8/compiler/astprocessing/CodeDesugarer.kt
index a5ba6374f..a1ad5b372 100644
--- a/compiler/src/prog8/compiler/astprocessing/CodeDesugarer.kt
+++ b/compiler/src/prog8/compiler/astprocessing/CodeDesugarer.kt
@@ -23,6 +23,7 @@ internal class CodeDesugarer(val program: Program,
     // - replace while and do-until loops by just jumps.
     // - replace peek() and poke() by direct memory accesses.
     // - repeat-forever loops replaced by label+jump.
+    // - pointer[word] replaced by @(pointer+word)
 
 
     override fun before(breakStmt: Break, parent: Node): Iterable<IAstModification> {
@@ -135,4 +136,31 @@ _after:
         }
         return noModifications
     }
+
+    override fun after(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> {
+        // replace pointervar[word] by @(pointervar+word)
+        val indexExpr = arrayIndexedExpression.indexer.indexExpr
+        val indexerDt = indexExpr.inferType(program)
+        if(indexerDt.isWords) {
+            val arrayVar = arrayIndexedExpression.arrayvar.targetVarDecl(program)!!
+            if(arrayVar.datatype==DataType.UWORD) {
+                val add: Expression =
+                    if(indexExpr.constValue(program)?.number==0.0)
+                        arrayIndexedExpression.arrayvar.copy()
+                    else
+                        BinaryExpression(arrayIndexedExpression.arrayvar.copy(), "+", indexExpr, arrayIndexedExpression.position)
+                return if(parent is AssignTarget) {
+                    // assignment to array
+                    val memwrite = DirectMemoryWrite(add, arrayIndexedExpression.position)
+                    val newtarget = AssignTarget(null, null, memwrite, arrayIndexedExpression.position)
+                    listOf(IAstModification.ReplaceNode(parent, newtarget, parent.parent))
+                } else {
+                    // read from array
+                    val memread = DirectMemoryRead(add, arrayIndexedExpression.position)
+                    listOf(IAstModification.ReplaceNode(arrayIndexedExpression, memread, parent))
+                }
+            }
+        }
+        return noModifications
+    }
 }
diff --git a/compiler/test/ast/TestVarious.kt b/compiler/test/ast/TestVarious.kt
index 9c07e71a5..dd58614b5 100644
--- a/compiler/test/ast/TestVarious.kt
+++ b/compiler/test/ast/TestVarious.kt
@@ -100,7 +100,6 @@ main {
             }
         }"""
         val result = compileText(C64Target(), optimize=false, src, writeAssembly=true)!!
-        printProgram(result.program)
         val stmts = result.program.entrypoint.statements
         stmts.size shouldBe 6
         val name1 = stmts[0] as VarDecl
@@ -114,5 +113,22 @@ main {
         (name2.targetVarDecl(result.program)!!.value as StringLiteral).value shouldBe "xx1xx2"
         (rept2.targetVarDecl(result.program)!!.value as StringLiteral).value shouldBe "xyzxyzxyzxyz"
     }
+
+    test("pointervariable indexing allowed with >255") {
+        val src="""
+main {
+    sub start() {
+        uword pointer = ${'$'}2000
+        @(pointer+${'$'}1000) = 123
+        ubyte @shared ub = @(pointer+${'$'}1000)
+        pointer[${'$'}1000] = 99
+        ub = pointer[${'$'}1000]
+        uword index = ${'$'}1000
+        pointer[index] = 55
+        ub = pointer[index]
+    }
+}"""
+        compileText(C64Target(), optimize=false, src, writeAssembly=false) shouldNotBe null
+    }
 })
 
diff --git a/docs/source/todo.rst b/docs/source/todo.rst
index d7637501c..3a130d76e 100644
--- a/docs/source/todo.rst
+++ b/docs/source/todo.rst
@@ -4,6 +4,8 @@ TODO
 For next release
 ^^^^^^^^^^^^^^^^
 - ir: asmsub contents remains blank in IR file
+- add cx16diskio.vload_raw() to load headerless files into vram
+- mention the syntax highlighting files in the readme and the docs, and add note to the IDEA one that it can also be used in Rider
 
 ...