Add resource shrinker sources to R8 repo
This is a verbatim copy for now since this will allow us to easily
merge in either direction - downside is that this does not pass our formatter.
I have added 8.2.20-dev to third_party/r8 to allow us to compile this standalone, this is not used when compiled into r8 (in a follow up). We should be able to refactor the setup to eventually not need this hack.
Add build setup in new gradle build files
Bug: 287398085
Change-Id: Ib9ab46acb67dc4d713e91b82f27b30ef67fb065a
diff --git a/src/resourceshrinker/java/com/android/build/shrinker/ResourceTableUtil.kt b/src/resourceshrinker/java/com/android/build/shrinker/ResourceTableUtil.kt
new file mode 100644
index 0000000..69952ef
--- /dev/null
+++ b/src/resourceshrinker/java/com/android/build/shrinker/ResourceTableUtil.kt
@@ -0,0 +1,118 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.build.shrinker
+
+import com.android.aapt.Resources
+
+internal fun Resources.ResourceTable.entriesSequence(): Sequence<EntryWrapper> = sequence {
+ for (resourcePackage in packageList) {
+ for (resourceType in resourcePackage.typeList) {
+ for (resourceEntry in resourceType.entryList) {
+ val id = toIdentifier(resourcePackage, resourceType, resourceEntry)
+ yield(
+ EntryWrapper(id, resourcePackage.packageName, resourceType.name, resourceEntry)
+ )
+ }
+ }
+ }
+}
+
+internal fun Resources.ResourceTable.nullOutEntriesWithIds(ids: List<Int>)
+ : Resources.ResourceTable {
+ if (ids.isEmpty()) {
+ return this
+ }
+ val packageMappings = calculatePackageMappings(ids)
+ val tableBuilder = this.toBuilder()
+ tableBuilder.packageBuilderList.forEach{
+ val typeMappings = packageMappings[it.packageId.id]
+ if (typeMappings != null) {
+ it.typeBuilderList.forEach { type->
+ val entryList = typeMappings[type.typeId.id]
+ if (entryList != null) {
+ type.entryBuilderList.forEach { entry ->
+ if (entryList.contains(entry.entryId.id)) {
+ entry.clearConfigValue()
+ if (entry.hasOverlayableItem()) {
+ entry.clearOverlayableItem()
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+ return tableBuilder.build()
+}
+
+private fun calculatePackageMappings(ids: List<Int>): MutableMap<Int, Map<Int, List<Int>>> {
+ val sortedIds = ids.sorted()
+ val packageMapping = mutableMapOf<Int, Map<Int, List<Int>>>()
+ var typeMapping = mutableMapOf<Int, List<Int>>()
+ var entryList = mutableListOf<Int>()
+ var oldPackageId = -1
+ var oldTypeId = -1
+ for (value in sortedIds) {
+ val packageId = packageIdFromIdentifier(value)
+ val typeId = typeIdFromIdentifier(value)
+ val entryId = entryIdFromIdentifier(value)
+ if (packageId != oldPackageId) {
+ typeMapping = mutableMapOf()
+ packageMapping.put(packageId, typeMapping)
+ oldPackageId = packageId
+ oldTypeId = -1
+ }
+ if (typeId != oldTypeId) {
+ entryList = mutableListOf()
+ typeMapping.put(typeId, entryList)
+ oldTypeId = typeId
+ }
+ entryList.add(entryId)
+ }
+ return packageMapping
+}
+
+internal data class EntryWrapper(
+ val id: Int,
+ val packageName: String,
+ val type: String,
+ val entry: Resources.Entry
+)
+
+private fun toIdentifier(
+ resourcePackage: Resources.Package,
+ type: Resources.Type,
+ entry: Resources.Entry
+): Int =
+ (resourcePackage.packageId.id shl 24) or (type.typeId.id shl 16) or entry.entryId.id
+
+private fun packageIdFromIdentifier(
+ identifier: Int
+): Int =
+ identifier shr 24
+
+private fun typeIdFromIdentifier(
+ identifier: Int
+): Int =
+ (identifier and 0x00FF0000) shr 16
+
+private fun entryIdFromIdentifier(
+ identifier: Int
+): Int =
+ (identifier and 0x0000FFFF)
+
+