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川合のプログラミング言語自作のためのテキスト第二版#0010

• (by K, 2019.06.30)

(18) TJ-03x

• 次はTJ-03aを書き直してみます。やってみたら61行になりました。

  #include "kll0.h"
  
  enum { EAX = 0, ECX = 1 };
  
  void sub_print(int i)
  {
      printf("%d\n", i);
  }
  
  void sub_time()
  {
      printf("time=%.3f[sec]\n", clock() / (double) CLOCKS_PER_SEC);
  }
  
  int main(int argc, const char **argv)
  {
      KLexer lx(NEW1(kautoreleasePool, KStringId)("; = + - print while ( < ) { } time"));
      char *txt = (char *) kerrorExitP0(kreadFileA(argv[1], "rt", 2), "usage>%s program-file", argv[0]);
      KLexer_Elmt *le = (KLexer_Elmt *) lx.add(txt)->p;
      int pc = 0, qc = 0, wqc = 0, wqc2 = 0, *var = (int *) kautoreleasePool->alloc((*lx.sid->n) * sizeof (int));
      for (int i = 0; i < *lx.sid->n; i++)
          var[i] = lx.getConstInt(i);	// intではないときは0を返す.
      unsigned char *code = (unsigned char *) kmallocRWX(1024 * 1024);
      qc += kputBin(&code[qc], "83_ec_7c"); // SUB ESP,124.  この命令でスタックを調整させる.
      for (int n = lx.getElmtLen(); pc < n; pc++) {
          if (le[pc + 1].i == 1) { // 2単語目が"=".
              if (le[pc + 3].i == 0) {	// 単純代入.
                  qc += kputBin(&code[qc], "8b_%i8_%i32  a3_%i32", EAX * 8 + 0x05, &var[le[pc + 2].i], &var[le[pc].i]);
              } else if (le[pc + 3].i == 2 && le[pc + 5].i == 0) { // 加算.
                  qc += kputBin(&code[qc], "8b_%i8_%i32  8b_%i8_%i32  01_c8  a3_%i32", EAX * 8 + 0x05, &var[le[pc + 2].i], ECX * 8 + 0x05, &var[le[pc + 4].i], &var[le[pc].i]);
              } else if (le[pc + 3].i == 3 && le[pc + 5].i == 0) { // 減算.
                  qc += kputBin(&code[qc], "8b_%i8_%i32  8b_%i8_%i32  29_c8  a3_%i32", EAX * 8 + 0x05, &var[le[pc + 2].i], ECX * 8 + 0x05, &var[le[pc + 4].i], &var[le[pc].i]);
              } else
                  goto err;
          } else if (le[pc].i == 5 && le[pc + 1].i == 6 && le[pc + 3].i == 7 && le[pc + 5].i == 8 && le[pc + 6].i == 9) {	// while.
              wqc = qc;
              qc += kputBin(&code[qc], "8b_%i8_%i32  8b_%i8_%i32  39_c8  0f_8d_%i32", EAX * 8 + 0x05, &var[le[pc + 2].i], ECX * 8 + 0x05, &var[le[pc + 4].i], &var[le[pc].i], 0);
              wqc2 = qc;
              pc += 7 - 1;
              continue;
          } else if (le[pc].i == 10) {
              qc += kputBin(&code[qc], "e9_%r32", &code[wqc]);
              kputBin(&code[wqc2 - 4], "%r32", &code[qc]);
              continue;
          } else if (le[pc].i == 11 && le[pc + 1].i == 0) { // time.
              qc += kputBin(&code[qc], "e8_%r32", sub_time);
          } else if (le[pc].i == 4 && le[pc + 2].i == 0) { // print.
              qc += kputBin(&code[qc], "8b_%i8_%i32  89_04_24  e8_%r32", EAX * 8 + 0x05, &var[le[pc + 1].i], sub_print);
          } else
              goto err;
          while (le[pc].i != 0)
              pc++;
      }
      qc += kputBin(&code[qc], "83_c4_7c  c3"); // ADD ESP,124.  最初に調整したスタックを元に戻す.  RET.
      void (*func)();	// funcは関数へのポインタ型の変数.
      func = (void (*)()) code;
      func();
      exit(0);
  err:
      kerrorExit("syntax error : %.30s", le[pc].p0);
  }

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