Ensure minimal move-exception live intervals
Change-Id: I6903c8fadb374bd4cd8a39054745aa99684837e5
diff --git a/src/main/java/com/android/tools/r8/ir/regalloc/LinearScanRegisterAllocator.java b/src/main/java/com/android/tools/r8/ir/regalloc/LinearScanRegisterAllocator.java
index bb5742b..3cc749b 100644
--- a/src/main/java/com/android/tools/r8/ir/regalloc/LinearScanRegisterAllocator.java
+++ b/src/main/java/com/android/tools/r8/ir/regalloc/LinearScanRegisterAllocator.java
@@ -30,6 +30,7 @@
import com.android.tools.r8.ir.code.InstructionListIterator;
import com.android.tools.r8.ir.code.Invoke;
import com.android.tools.r8.ir.code.Move;
+import com.android.tools.r8.ir.code.MoveException;
import com.android.tools.r8.ir.code.NumericType;
import com.android.tools.r8.ir.code.Or;
import com.android.tools.r8.ir.code.Phi;
@@ -1121,29 +1122,29 @@
// When we allow argument reuse we do not allow any splitting, therefore we cannot get into
// trouble with move exception registers. When argument reuse is disallowed we block a fixed
// register to be used only by move exception instructions.
- if (!mode.is4Bit() || hasInvokeRangeLiveIntervals) {
- // Force all move exception ranges to start out with the exception in a fixed register.
- for (BasicBlock block : code.blocks) {
- Instruction instruction = block.entry();
- if (instruction.isMoveException()) {
- LiveIntervals intervals = instruction.outValue().getLiveIntervals();
- unhandled.remove(intervals);
- moveExceptionIntervals.add(intervals);
- intervals.setRegister(getMoveExceptionRegister());
- }
+ if (mode.is4Bit() && !hasInvokeRangeLiveIntervals) {
+ return;
+ }
+ // Force all move exception ranges to start out with the exception in a fixed register.
+ for (BasicBlock block : code.blocks(block -> block.entry().isMoveException())) {
+ MoveException moveException = block.entry().asMoveException();
+ LiveIntervals intervals = moveException.outValue().getLiveIntervals();
+ if (intervals.getValue().hasAnyUsers()) {
+ LiveIntervals split = intervals.splitAfter(intervals.getValue().getDefinition());
+ unhandled.add(split);
}
- if (hasDedicatedMoveExceptionRegister()) {
- int moveExceptionRegister = getMoveExceptionRegister();
- assert moveExceptionRegister == maxRegisterNumber + 1;
- increaseCapacity(moveExceptionRegister, true);
+ if (intervals.getStart() < moveException.getNumber()) {
+ intervals = intervals.splitBefore(moveException);
+ } else {
+ unhandled.remove(intervals);
}
- // Split their live ranges which will force another register if used.
- for (LiveIntervals intervals : moveExceptionIntervals) {
- if (intervals.getValue().hasAnyUsers()) {
- LiveIntervals split = intervals.splitAfter(intervals.getValue().getDefinition());
- unhandled.add(split);
- }
- }
+ moveExceptionIntervals.add(intervals);
+ intervals.setRegister(getMoveExceptionRegister());
+ }
+ if (hasDedicatedMoveExceptionRegister()) {
+ int moveExceptionRegister = getMoveExceptionRegister();
+ assert moveExceptionRegister == maxRegisterNumber + 1;
+ increaseCapacity(moveExceptionRegister, false);
}
}
