Merge "Lazily introduce values for uninitialized debug locals."
diff --git a/src/main/java/com/android/tools/r8/ir/conversion/IRBuilder.java b/src/main/java/com/android/tools/r8/ir/conversion/IRBuilder.java
index 98b4502..e66ddfc 100644
--- a/src/main/java/com/android/tools/r8/ir/conversion/IRBuilder.java
+++ b/src/main/java/com/android/tools/r8/ir/conversion/IRBuilder.java
@@ -87,6 +87,7 @@
import com.android.tools.r8.utils.Pair;
import it.unimi.dsi.fastutil.ints.Int2ReferenceAVLTreeMap;
import it.unimi.dsi.fastutil.ints.Int2ReferenceMap;
+import it.unimi.dsi.fastutil.ints.Int2ReferenceOpenHashMap;
import it.unimi.dsi.fastutil.ints.Int2ReferenceSortedMap;
import it.unimi.dsi.fastutil.ints.IntArrayList;
import it.unimi.dsi.fastutil.ints.IntArraySet;
@@ -309,6 +310,7 @@
// Basic blocks. Added after processing from the worklist.
private final LinkedList<BasicBlock> blocks = new LinkedList<>();
+ private BasicBlock entryBlock = null;
private BasicBlock currentBlock = null;
final private ValueNumberGenerator valueNumberGenerator;
private final DexEncodedMethod method;
@@ -324,6 +326,9 @@
private Value previousLocalValue = null;
private final List<Value> debugLocalReads = new ArrayList<>();
+ // Lazily populated list of local values that are referenced without being actually defined.
+ private Int2ReferenceMap<List<Value>> uninitializedDebugLocalValues = null;
+
private int nextBlockNumber = 0;
// Flag indicating if the instructions define values with imprecise types.
@@ -420,6 +425,7 @@
processedInstructions = null;
setCurrentBlock(targets.get(INITIAL_BLOCK_OFFSET).block);
+ entryBlock = currentBlock;
source.buildPrelude(this);
// Process normal blocks reachable from the entry block using a worklist of reachable
@@ -438,6 +444,21 @@
// Insert debug positions so all position changes are marked by an explicit instruction.
boolean hasDebugPositions = insertDebugPositions();
+ // Insert definitions for all uninitialized local values.
+ if (uninitializedDebugLocalValues != null) {
+ InstructionListIterator it = entryBlock.listIterator();
+ it.nextUntil(i -> !i.isArgument());
+ it.previous();
+ for (List<Value> values : uninitializedDebugLocalValues.values()) {
+ for (Value value : values) {
+ Instruction def = new DebugLocalUninitialized(value);
+ def.setBlock(entryBlock);
+ def.setPosition(Position.none());
+ it.add(def);
+ }
+ }
+ }
+
// Clear all reaching definitions to free up memory (and avoid invalid use).
for (BasicBlock block : blocks) {
block.clearCurrentDefinitions();
@@ -648,15 +669,6 @@
addInstruction(new Argument(value));
}
- public void addDebugUninitialized(int register, ValueType type) {
- if (!options.debug) {
- return;
- }
- Value value = writeRegister(register, type, ThrowingInfo.NO_THROW, null);
- assert !value.hasLocalInfo();
- addInstruction(new DebugLocalUninitialized(value));
- }
-
private void addDebugLocalWrite(ValueType type, int dest, Value in) {
assert options.debug;
Value out = writeRegister(dest, type, ThrowingInfo.NO_THROW);
@@ -670,7 +682,7 @@
assert local != null;
assert local == getIncomingLocal(register);
ValueType valueType = ValueType.fromDexType(local.type);
- return readRegisterIgnoreLocal(register, valueType);
+ return readRegisterIgnoreLocal(register, valueType, local);
}
private static boolean isValidFor(Value value, DebugLocalInfo local) {
@@ -697,7 +709,7 @@
assert local == getOutgoingLocal(register);
ValueType valueType = ValueType.fromDexType(local.type);
// TODO(mathiasr): Here we create a Phi with type based on debug info. That's just wrong!
- Value incomingValue = readRegisterIgnoreLocal(register, valueType);
+ Value incomingValue = readRegisterIgnoreLocal(register, valueType, local);
// TODO(mathiasr): This can be simplified once trivial phi removal is local-info aware.
if (incomingValue.isPhi() || incomingValue.getLocalInfo() != local) {
@@ -1672,8 +1684,7 @@
return value;
}
- private Value readRegisterIgnoreLocal(int register, ValueType type) {
- DebugLocalInfo local = getIncomingLocal(register);
+ private Value readRegisterIgnoreLocal(int register, ValueType type, DebugLocalInfo local) {
return readRegister(register, type, currentBlock, EdgeType.NON_EDGE, local);
}
@@ -1707,7 +1718,14 @@
}
// If the register still has unknown value create a phi value for it.
if (value == null) {
- if (!block.isSealed()) {
+ if (block == entryBlock && local != null) {
+ assert block.getPredecessors().isEmpty();
+ // If a debug-local is referenced at the entry block, lazily introduce an SSA value for it.
+ // This value must *not* be added to the entry blocks current definitions since
+ // uninitialized debug-locals may be reference at the same register/local-index yet be of
+ // different types (eg, int in one part of the CFG and float in a disjoint part).
+ value = getUninitializedDebugLocalValue(register, type, local);
+ } else if (!block.isSealed()) {
assert !blocks.isEmpty() : "No write to " + register;
Phi phi = new Phi(valueNumberGenerator.next(), block, type, local);
block.addIncompletePhi(register, phi, readingEdge);
@@ -1734,6 +1752,29 @@
return value;
}
+ private Value getUninitializedDebugLocalValue(
+ int register, ValueType type, DebugLocalInfo local) {
+ assert type == ValueType.fromDexType(local.type);
+ if (uninitializedDebugLocalValues == null) {
+ uninitializedDebugLocalValues = new Int2ReferenceOpenHashMap<>();
+ }
+ List<Value> values = uninitializedDebugLocalValues.get(register);
+ if (values != null) {
+ for (Value value : values) {
+ if (value.outType() == type) {
+ return value;
+ }
+ }
+ } else {
+ uninitializedDebugLocalValues.put(register, new ArrayList<>(2));
+ }
+ // Create a new SSA value for the uninitialized local value.
+ // Note that the uninitialized local value *does not* itself have local information!
+ Value value = new Value(valueNumberGenerator.next(), type, null);
+ uninitializedDebugLocalValues.get(register).add(value);
+ return value;
+ }
+
public Value readNumericRegister(int register, NumericType type) {
return readRegister(register, ValueType.fromNumericType(type));
}
@@ -1785,7 +1826,7 @@
previousLocalValue =
(incomingLocal == null || incomingLocal != outgoingLocal)
? null
- : readRegisterIgnoreLocal(register, type);
+ : readRegisterIgnoreLocal(register, type, incomingLocal);
return writeRegister(register, type, throwing, outgoingLocal);
}
diff --git a/src/main/java/com/android/tools/r8/ir/conversion/JarSourceCode.java b/src/main/java/com/android/tools/r8/ir/conversion/JarSourceCode.java
index 85a0f99..01c4dd0 100644
--- a/src/main/java/com/android/tools/r8/ir/conversion/JarSourceCode.java
+++ b/src/main/java/com/android/tools/r8/ir/conversion/JarSourceCode.java
@@ -29,7 +29,6 @@
import com.android.tools.r8.ir.conversion.JarState.Slot;
import com.android.tools.r8.logging.Log;
import it.unimi.dsi.fastutil.ints.Int2ReferenceMap;
-import it.unimi.dsi.fastutil.ints.Int2ReferenceMap.Entry;
import it.unimi.dsi.fastutil.ints.Int2ReferenceOpenHashMap;
import it.unimi.dsi.fastutil.ints.Int2ReferenceSortedMap;
import java.io.PrintWriter;
@@ -275,7 +274,6 @@
// Record types for arguments.
Int2ReferenceMap<ValueType> argumentLocals = recordArgumentTypes();
Int2ReferenceMap<ValueType> initializedLocals = new Int2ReferenceOpenHashMap<>(argumentLocals);
- Int2ReferenceMap<ValueType> uninitializedLocals = new Int2ReferenceOpenHashMap<>();
// Initialize all non-argument locals to ensure safe insertion of debug-local instructions.
for (Object o : node.localVariables) {
LocalVariableNode local = (LocalVariableNode) o;
@@ -320,11 +318,9 @@
int localRegister = state.getLocalRegister(local.index, localType);
ValueType existingLocalType = initializedLocals.get(localRegister);
if (existingLocalType == null) {
- // For uninitialized entries write the local to ensure it exists in the local state.
int writeRegister = state.writeLocal(local.index, localType);
assert writeRegister == localRegister;
initializedLocals.put(localRegister, localValueType);
- uninitializedLocals.put(localRegister, localValueType);
}
}
@@ -335,10 +331,6 @@
// for arguments.
buildArgumentInstructions(builder);
- for (Entry<ValueType> entry : uninitializedLocals.int2ReferenceEntrySet()) {
- builder.addDebugUninitialized(entry.getIntKey(), entry.getValue());
- }
-
// Add debug information for all locals at the initial label.
for (Local local : state.getLocalsToOpen()) {
if (!argumentLocals.containsKey(local.slot.register)) {
