From 85b1d52a5c5183ec9e2b25f61d0038b6c539c75a Mon Sep 17 00:00:00 2001
From: Graham <gpe@openrs2.org>
Date: Fri, 20 Oct 2023 21:59:28 +0100
Subject: [PATCH] Include last instruction in expression in getExpression
 output

Every call site except replaceExpression() appended the last instruction
to the end of the list.

Signed-off-by: Graham <gpe@openrs2.org>
---
 asm/src/main/kotlin/org/openrs2/asm/InsnListUtils.kt       | 5 ++---
 .../openrs2/deob/bytecode/remap/StaticFieldUnscrambler.kt  | 3 +--
 .../org/openrs2/patcher/transform/HighDpiTransformer.kt    | 7 +------
 3 files changed, 4 insertions(+), 11 deletions(-)

diff --git a/asm/src/main/kotlin/org/openrs2/asm/InsnListUtils.kt b/asm/src/main/kotlin/org/openrs2/asm/InsnListUtils.kt
index da159fa2..6cd8eacb 100644
--- a/asm/src/main/kotlin/org/openrs2/asm/InsnListUtils.kt
+++ b/asm/src/main/kotlin/org/openrs2/asm/InsnListUtils.kt
@@ -16,8 +16,8 @@ public fun getExpression(
     var insn: AbstractInsnNode? = last
     do {
         val (pops, pushes) = insn!!.stackMetadata
+        expr.add(insn)
         if (insn !== last) {
-            expr.add(insn)
             height -= pushes
         }
         height += pops
@@ -38,7 +38,7 @@ public fun InsnList.replaceExpression(
     filter: (AbstractInsnNode) -> Boolean = ANY_INSN
 ): Boolean {
     val expr = getExpression(last, filter) ?: return false
-    expr.forEach(this::remove)
+    expr.filter { it !== last }.forEach(this::remove)
     this[last] = replacement
     return true
 }
@@ -49,7 +49,6 @@ public fun InsnList.deleteExpression(
 ): Boolean {
     val expr = getExpression(last, filter) ?: return false
     expr.forEach(this::remove)
-    remove(last)
     return true
 }
 
diff --git a/deob-bytecode/src/main/kotlin/org/openrs2/deob/bytecode/remap/StaticFieldUnscrambler.kt b/deob-bytecode/src/main/kotlin/org/openrs2/deob/bytecode/remap/StaticFieldUnscrambler.kt
index 15cbd743..92739f06 100644
--- a/deob-bytecode/src/main/kotlin/org/openrs2/deob/bytecode/remap/StaticFieldUnscrambler.kt
+++ b/deob-bytecode/src/main/kotlin/org/openrs2/deob/bytecode/remap/StaticFieldUnscrambler.kt
@@ -105,8 +105,7 @@ public class StaticFieldUnscrambler(
             }
 
             // TODO(gpe): use a filter here (pure with no *LOADs?)
-            val expr = getExpression(putstatic) ?: continue
-            simpleInitializers[desc] = expr.plus(putstatic)
+            simpleInitializers[desc] = getExpression(putstatic) ?: continue
         }
 
         return Pair(simpleInitializers, complexInitializers)
diff --git a/patcher/src/main/kotlin/org/openrs2/patcher/transform/HighDpiTransformer.kt b/patcher/src/main/kotlin/org/openrs2/patcher/transform/HighDpiTransformer.kt
index 56787e1e..69597eac 100644
--- a/patcher/src/main/kotlin/org/openrs2/patcher/transform/HighDpiTransformer.kt
+++ b/patcher/src/main/kotlin/org/openrs2/patcher/transform/HighDpiTransformer.kt
@@ -22,7 +22,6 @@ import org.openrs2.asm.classpath.ClassPath
 import org.openrs2.asm.classpath.Library
 import org.openrs2.asm.getExpression
 import org.openrs2.asm.previousReal
-import org.openrs2.asm.stackMetadata
 import org.openrs2.asm.transform.Transformer
 import kotlin.math.max
 
@@ -272,11 +271,7 @@ public class HighDpiTransformer : Transformer() {
         var head = invoke.previousReal ?: return false
 
         while (exprs.size < 4) {
-            val expr = if (head.stackMetadata.pops == 0) {
-                listOf(head)
-            } else {
-                getExpression(head)?.plus(head) ?: return false
-            }
+            val expr = getExpression(head) ?: return false
 
             if (invoke.name == "glViewport" && expr.any { it.opcode == Opcodes.IALOAD }) {
                 /*