From 12cb7d7abe5651ae599706d136fb022bb867008d Mon Sep 17 00:00:00 2001
From: Irmen de Jong <irmen@razorvine.net>
Date: Wed, 10 Jul 2019 01:52:04 +0200
Subject: [PATCH] optimize redundant typecasts more

---
 compiler/src/prog8/ast/base/Base.kt                 |  2 +-
 compiler/src/prog8/optimizer/SimplifyExpressions.kt | 13 +++++++++++--
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/compiler/src/prog8/ast/base/Base.kt b/compiler/src/prog8/ast/base/Base.kt
index 150927433..b30f5afef 100644
--- a/compiler/src/prog8/ast/base/Base.kt
+++ b/compiler/src/prog8/ast/base/Base.kt
@@ -38,7 +38,7 @@ enum class DataType {
 
     infix fun isAssignableTo(targetTypes: Set<DataType>) = targetTypes.any { this isAssignableTo it }
 
-    infix fun biggerThan(other: DataType) =
+    infix fun largerThan(other: DataType) =
             when(this) {
                 in ByteDatatypes -> false
                 in WordDatatypes -> other in ByteDatatypes
diff --git a/compiler/src/prog8/optimizer/SimplifyExpressions.kt b/compiler/src/prog8/optimizer/SimplifyExpressions.kt
index 5395151e2..14e58c94e 100644
--- a/compiler/src/prog8/optimizer/SimplifyExpressions.kt
+++ b/compiler/src/prog8/optimizer/SimplifyExpressions.kt
@@ -49,6 +49,15 @@ internal class SimplifyExpressions(private val program: Program) : IAstModifying
                         return tc.expression
                     }
                 }
+
+                // if the previous typecast was casting to a 'bigger' type, just ignore that one
+                val subTc = tc.expression as? TypecastExpression
+                if(subTc!=null && subTc.type largerThan tc.type) {
+                    subTc.type = tc.type
+                    subTc.parent = tc.parent
+                    optimizationsDone++
+                    return subTc
+                }
                 return super.visit(tc)
             }
             optimizationsDone++
@@ -385,7 +394,7 @@ internal class SimplifyExpressions(private val program: Program) : IAstModifying
         }
 
         if(leftConstVal==null && rightConstVal!=null) {
-            if(leftDt biggerThan rightDt) {
+            if(leftDt largerThan rightDt) {
                 val (adjusted, newValue) = adjust(rightConstVal, leftDt)
                 if (adjusted) {
                     expr.right = newValue
@@ -395,7 +404,7 @@ internal class SimplifyExpressions(private val program: Program) : IAstModifying
             }
             return false
         } else if(leftConstVal!=null && rightConstVal==null) {
-            if(rightDt biggerThan leftDt) {
+            if(rightDt largerThan leftDt) {
                 val (adjusted, newValue) = adjust(leftConstVal, rightDt)
                 if (adjusted) {
                     expr.left = newValue