public final void setNewSources(RegisterSpecList newSources) {
    RegisterSpecList origSources = insn.getSources();

    if (origSources.size() != newSources.size()) {
      throw new RuntimeException("Sources counts don't match");
    }

    insn = insn.withNewRegisters(getResult(), newSources);
  }
Changes the source list of the insn. New source list should be the same size and consist of
sources of identical types.

@param newSources non-null new sources list.
android/android_framework/dex-maker/src/main/java/com/android/dx/ssa/NormalSsaInsn.java