ELVMRegisterInfo.td

バックエンドのレジスタの情報を記述

  // Register classes.
  def GPR : RegisterClass<"ELVM", [i32], 32, (add B, C, D,
                                              A,  // return value
                                              SP, // stack ptr
                                              BP  // frame ptr
                                             )> {
    // tablegen is told to think 1byte is 8bits.
    let Size = 8;
    let Alignment = 8;
  }

General purpose register しか無いのでシンプル