public RegisterSpecSet getStarts(BasicBlock block) {
    return getStarts(block.getLabel());
  }
Gets the register set associated with the start of the given block. This is just convenient
shorthand for {@code getStarts(block.getLabel())}.

@param block {@code non-null;} the block in question
@return {@code non-null;} the associated register set
android/android_framework/dex-maker/src/main/java/com/android/dx/rop/code/LocalVariableInfo.java