[llvm] [WIP][CodeGen] Encode liveness for COPY instructions after virtRegRewriter pass. (PR #151123)

[Christudasan Devadasan via llvm-commits]

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@@ -641,11 +718,14 @@ void VirtRegRewriter::rewrite() {
   SmallVector<Register, 8> SuperDeads;
   SmallVector<Register, 8> SuperDefs;
   SmallVector<Register, 8> SuperKills;
+  uint64_t Mask;
 
   for (MachineFunction::iterator MBBI = MF->begin(), MBBE = MF->end();
        MBBI != MBBE; ++MBBI) {
     LLVM_DEBUG(MBBI->print(dbgs(), Indexes));
     for (MachineInstr &MI : llvm::make_early_inc_range(MBBI->instrs())) {
+      // reset for each MI.
+      Mask = 0u;
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cdevadas wrote:

Use LaneBitmask::getNone() to clear all bits.

https://github.com/llvm/llvm-project/pull/151123