continue;
// Update def for Reg and aliases.
- for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI)
+ for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI) {
+ // We need to be careful here not to define already-live super registers.
+ // If the super register is already live, then this definition is not
+ // a definition of the whole super register (just a partial insertion
+ // into it). Earlier subregister definitions (which we've not yet visited
+ // because we're iterating bottom-up) need to be linked to the same group
+ // as this definition.
+ if (TRI->isSuperRegister(Reg, *AI) && State->IsLive(*AI))
+ continue;
+
DefIndices[*AI] = Count;
+ }
}
}