Make moves from argument registers block moves to argument registers
Bug: 126273993
Change-Id: I72b5c0184ead2d5b0a857aa46303750e4b4561ab
diff --git a/src/main/java/com/android/tools/r8/ir/regalloc/RegisterMove.java b/src/main/java/com/android/tools/r8/ir/regalloc/RegisterMove.java
index fb681b9..92992e8 100644
--- a/src/main/java/com/android/tools/r8/ir/regalloc/RegisterMove.java
+++ b/src/main/java/com/android/tools/r8/ir/regalloc/RegisterMove.java
@@ -25,7 +25,7 @@
}
public RegisterMove(int dst, TypeLatticeElement type, Instruction definition) {
- assert definition.isOutConstant() || definition.isArgument();
+ assert definition.isOutConstant();
this.dst = dst;
this.src = LiveIntervals.NO_REGISTER;
this.definition = definition;
diff --git a/src/main/java/com/android/tools/r8/ir/regalloc/SpillMoveSet.java b/src/main/java/com/android/tools/r8/ir/regalloc/SpillMoveSet.java
index 0d25746..aad705f 100644
--- a/src/main/java/com/android/tools/r8/ir/regalloc/SpillMoveSet.java
+++ b/src/main/java/com/android/tools/r8/ir/regalloc/SpillMoveSet.java
@@ -353,9 +353,18 @@
// Use rematerialization when possible and otherwise generate moves.
if (move.from.isSpilledAndRematerializable()) {
assert allocator.unadjustedRealRegisterFromAllocated(move.to.getRegister()) < 256;
- scheduler.addMove(
- new RegisterMove(move.to.getRegister(), move.type, move.from.getValue().definition));
- } else if (move.to.getRegister() != move.from.getRegister()) {
+ Instruction definition = move.from.getValue().definition;
+ if (definition.isOutConstant()) {
+ scheduler.addMove(new RegisterMove(move.to.getRegister(), move.type, definition));
+ continue;
+ } else {
+ // The src value is an argument, so we must create a register move that has a src
+ // register, using the code below, to ensure that other moves that have the argument
+ // register as dest are blocked by this move.
+ assert definition.isArgument();
+ }
+ }
+ if (move.to.getRegister() != move.from.getRegister()) {
// In case the runtime might have a bound-check elimination bug we make sure to define all
// indexing constants with an actual const instruction rather than a move. This appears to
// avoid a bug where the index variable could end up being uninitialized.
