commit 2373aae865939e8feb1732cdd6535bacedf084b2
author Rico Wind <ricow@google.com> Tue May 23 14:12:12 2023 +0200
committer Rico Wind <ricow@google.com> Tue May 23 13:30:51 2023 +0000
tree 88306ebfded8750ddabf080114b4751612c1ddca
parent 957cb221cc0ce446eca54107b1e65c9d399e47c2

Don't cannonicalize code objects when reading

Previously we would not canonicalize code objects, but our reader
would still assume that the object could be canonicalized and would
leave them canonicalized if they where.

The remainder of the pipeline assumes that we can change the code
objects, e.g., when jumbostring rewriting where we hit this when
merging already dexed and dedupped code objects.

Bug: 283145010
Change-Id: I409fe3fbcc56a87b604cc6c0ae2021b7d8e0c088

src/main/java/com/android/tools/r8/dex/DexParser.java

diff --git a/src/main/java/com/android/tools/r8/dex/DexParser.java b/src/main/java/com/android/tools/r8/dex/DexParser.java
index 2055d69..bc293d3 100644
--- a/src/main/java/com/android/tools/r8/dex/DexParser.java
+++ b/src/main/java/com/android/tools/r8/dex/DexParser.java
@@ -121,7 +121,6 @@
   public void close() {
     // This close behavior is needed to reduce peak memory usage of D8/R8.
     indexedItems = null;
-    codes = null;
     offsetMap = null;
     dexReader = null;
     stringIDs = null;
@@ -130,9 +129,6 @@
   // Mapping from indexes to indexable dex items.
   private OffsetToObjectMapping indexedItems = new OffsetToObjectMapping();
 
-  // Mapping from offset to code item;
-  private Int2ReferenceMap<DexCode> codes = new Int2ReferenceOpenHashMap<>();
-
   // Mapping from offset to dex item;
   private Int2ReferenceMap<Object> offsetMap = new Int2ReferenceOpenHashMap<>();
 
@@ -172,32 +168,28 @@
     this.options = options;
   }
 
-  private void ensureCodesInited(int offset) {
+  // We explicitly reread the code objects even if they are deduplicated in the input (i.e., two
+  // methods point to the same code object) to allow us to change code objects in our pipeline.
+  private DexCode readCodeObject(int offset) {
     if (offset == 0) {
-      return;
-    }
-
-    if (codes == null) {
-      codes = new Int2ReferenceOpenHashMap<>();
+      return null;
     }
 
     if (classKind == ClassKind.LIBRARY) {
       // Ignore contents of library files.
-      return;
+      return null;
     }
     DexSection dexSection = lookupSection(Constants.TYPE_CODE_ITEM);
     if (dexSection.length == 0) {
-      return;
+      return null;
     }
 
-    if (!codes.containsKey(offset)) {
-      int currentPos = dexReader.position();
-      dexReader.position(offset);
-      dexReader.align(4);
-      DexCode code = parseCodeItem();
-      codes.put(offset, code); // Update the file local offset to code mapping.
-      dexReader.position(currentPos);
-    }
+    int currentPos = dexReader.position();
+    dexReader.position(offset);
+    dexReader.align(4);
+    DexCode code = parseCodeItem();
+    dexReader.position(currentPos);
+    return code;
   }
 
   private DexTypeList parseTypeList() {
@@ -758,9 +750,7 @@
       int codeOff = dexReader.getUleb128();
       DexCode code = null;
       if (!skipCodes) {
-        ensureCodesInited(codeOff);
-        assert codeOff == 0 || codes.get(codeOff) != null;
-        code = codes.get(codeOff);
+        code = readCodeObject(codeOff);
       }
       DexMethod method = indexedItems.getMethod(methodIndex);
       accessFlags.setConstructor(method, dexItemFactory);