示例#1
0
文件: bp.c 项目: pcpa/lightning
int main()
{
  pifi      nfibs;
  int	    in;				/* offset of the argument */
  jit_insn  *ref;			/* to patch the forward reference */
  jit_insn  *mref;                     /* ref of move to backpatch */
  jit_insn  *tp;                       /* location to patch */

  codeBuffer = mmap(NULL, getpagesize(), PROT_READ | PROT_WRITE | PROT_EXEC,
                    MAP_PRIVATE | MAP_ANON, -1, 0);
  if (codeBuffer == MAP_FAILED) {
    perror("mmap");
    exit(0);
  }

  nfibs = (pifi) (jit_set_ip(codeBuffer).iptr);

        jit_prolog   (1);
  in =  jit_arg_ui   ();
        jit_getarg_ui(JIT_V0, in);              /* V0 = n */
  mref= jit_movi_p(JIT_V2,jit_forward ());      /* Generate a dumb movi */
        jit_jmpr(JIT_V2);
        /* generate some dump filler that will never be executed!*/
        jit_addi_ui(JIT_V0,JIT_V0,1);
        jit_addi_ui(JIT_V0,JIT_V0,1);        
        jit_addi_ui(JIT_V0,JIT_V0,1);        
        jit_addi_ui(JIT_V0,JIT_V0,1);        
  tp  = jit_get_label ();
  ref = jit_blti_ui  (jit_forward(), JIT_V0, 2);
        jit_subi_ui  (JIT_V1, JIT_V0, 1);       /* V1 = n-1 */
        jit_subi_ui  (JIT_V2, JIT_V0, 2);       /* V2 = n-2 */
        jit_prepare  (1);
          jit_pusharg_ui(JIT_V1);
        jit_finish(nfibs);
        jit_retval(JIT_V1);                     /* V1 = nfibs(n-1) */
        jit_prepare(1);
          jit_pusharg_ui(JIT_V2);
        jit_finish(nfibs);
        jit_retval(JIT_V2);                     /* V2 = nfibs(n-2) */
        jit_addi_ui(JIT_V1,  JIT_V1,  1);
        jit_addr_ui(JIT_RET, JIT_V1, JIT_V2);   /* RET = V1 + V2 + 1 */
        jit_ret();

  jit_patch(ref);                               /* patch jump */
        jit_movi_i(JIT_RET, 1);                 /* RET = 1 */
        jit_ret();

  jit_patch_movi(mref,tp);                      /* Ok. Do the back-patching */

  /* call the generated code, passing 32 as an argument */
  jit_flush_code(codeBuffer, jit_get_ip().ptr);

#ifdef LIGHTNING_DISASSEMBLE
  disassemble(stderr, (char *)codeBuffer, jit_get_ip().ptr);
#endif
#ifndef LIGHTNING_CROSS
  printf("nfibs(%d) = %d\n", 32, nfibs(32));
#endif
  return 0;
}
示例#2
0
int main()
{
  pifi      nfibs = (pifi) (jit_set_ip(codeBuffer).iptr);
  int	    in;				/* offset of the argument */
  jit_insn  *ref;			/* to patch the forward reference */
  jit_insn  *loop;			/* start of the loop */

        jit_prolog   (1);
  in =  jit_arg_ui   ();
        jit_getarg_ui(JIT_R2, in);              /* V0 = n */
        jit_movi_ui  (JIT_R1, 1);
  ref = jit_blti_ui  (jit_forward(), JIT_R2, 2);
        jit_subi_ui  (JIT_R2, JIT_R2, 1);
        jit_movi_ui  (JIT_R0, 1);

  loop= jit_get_label();
        jit_subi_ui  (JIT_R2, JIT_R2, 1);	/* we'll calculate one more */
        jit_addr_ui  (JIT_V0, JIT_R0, JIT_R1);  /* V0 = R0 + R1 */
        jit_movr_ui  (JIT_R0, JIT_R1);          /* R0 = R1 */
        jit_addi_ui  (JIT_R1, JIT_V0, 1);       /* R1 = V0 + 1 */
        jit_bnei_ui  (loop, JIT_R2, 0);         /* if (R2) goto loop; */

  jit_patch(ref);                               /* patch forward jump */
        jit_movr_ui  (JIT_RET, JIT_R1);         /* RET = R1 */
        jit_ret();

  jit_flush_code(codeBuffer, jit_get_ip().ptr);

#ifdef LIGHTNING_DISASSEMBLE
  disassemble(stderr, (char *) codeBuffer, jit_get_ip().ptr);
#endif
#ifndef LIGHTNING_CROSS
  /* call the generated code, passing 36 as an argument */
  printf("nfibs(%d) = %d\n", 36, nfibs(36));
#endif
  return 0;
}
示例#3
0
jit_pointer_t compile(const std::vector<Oper>& ops, jit_word_t *memory, const bool flush = true)
{
  jit_prolog();
  jit_movi(JIT_V0, reinterpret_cast<jit_word_t>(memory));
  jit_movi(JIT_V1, 0);

  std::stack<Loop> loops;

  jit_node_t* start = jit_note(__FILE__, __LINE__);

  for ( size_t n=0; n<ops.size(); ++n ) {
    switch ( ops[n].code ) {
      case '<':
        jit_str(JIT_V0, JIT_V1);
        jit_subi(JIT_V0, JIT_V0, ops[n].count * sizeof(jit_word_t));
        jit_ldr(JIT_V1, JIT_V0);
        break;

      case '>':
        jit_str(JIT_V0, JIT_V1);
        jit_addi(JIT_V0, JIT_V0, ops[n].count * sizeof(jit_word_t));
        jit_ldr(JIT_V1, JIT_V0);
        break;

      case 'z':
        jit_movi(JIT_V1, 0);
        break;

      case '+':
        jit_addi(JIT_V1, JIT_V1, ops[n].count);
        break;

      case '-':
        jit_subi(JIT_V1, JIT_V1, ops[n].count);
        break;

      case '.':
        jit_prepare();
        jit_pushargr(JIT_V1);
        jit_finishi(reinterpret_cast<jit_pointer_t>(putchar));

        if ( flush ) {
          jit_prepare();
          jit_pushargi(reinterpret_cast<jit_word_t>(stdout));
          jit_finishi(reinterpret_cast<jit_pointer_t>(fflush));
        }
        break;

      case ',':
        jit_prepare();
        jit_finishi(reinterpret_cast<jit_pointer_t>(getchar));
        jit_retval(JIT_V1);
        break;

      case '[': {
        Loop loop;
        loop.end = jit_forward();
        jit_node_t *j = jit_beqi(JIT_V1, 0);
        jit_patch_at(j, loop.end);
        loop.body = jit_label();
        loops.push(loop);
      } break;

      case ']': {
        Loop loop = loops.top();
        jit_node_t *j = jit_bnei(JIT_V1, 0);
        jit_patch_at(j, loop.body);
        jit_link(loop.end);
        loops.pop();
        break;
      }
      default:
        break;
    }
  }

  jit_node_t* stop = jit_note(__FILE__, __LINE__);

  jit_ret();
  jit_epilog();
  jit_pointer_t r = jit_emit();
  fprintf(stderr, "compiled to %zu bytes\n", (char*)jit_address(stop) -
      (char*)jit_address(start));
  return r;
}
示例#4
0
void
run_gnulightning(void)
{
    struct bfi * n = bfprog;
    int maxstack = 0, stackptr = 0;
    char *strbuf = 0;
    size_t maxstrlen = 0;
#ifdef GNULIGHTv1
    jit_insn** loopstack = 0;
    jit_insn *codeBuffer;
    void * startptr;
    int argp;
#endif
#ifdef GNULIGHTv2
    jit_node_t    *start, *end;	    /* For size of code */
    jit_node_t** loopstack = 0;
    jit_node_t    *argp;
#endif

    if (cell_size == 8) tape_step = 1; else
    tape_step = sizeof(int);

#ifdef GNULIGHTv1
    /* TODO: Use mmap for allocating memory, the x86 execute protection
     * bit is on the segment so Linux has to say thay everything below
     * a specific address is executable. If you ask mmap for executable
     * memory it can put it below the current value. The mprotect()
     * function can't do this.
     */
    if (total_nodes < 4096)
	codeBuffer = malloc(65536);
    else
	codeBuffer = malloc(16 * total_nodes);
    save_ptr_for_free(codeBuffer);

    codeptr = (codeptr_t) jit_set_ip(codeBuffer).vptr;
    startptr = jit_get_ip().ptr;
    /* Function call prolog */
    jit_prolog(1);
    /* Get the data area pointer */
    argp = jit_arg_p();
    jit_getarg_p(REG_P, argp);
#endif

#ifdef GNULIGHTv2
    init_jit(NULL); // argv[0]);
    _jit = jit_new_state();
    start = jit_note(__FILE__, __LINE__);
    jit_prolog();

    /* Get the data area pointer */
    argp = jit_arg();
    jit_getarg(REG_P, argp);
#endif

    while(n)
    {
	switch(n->type)
	{
	case T_MOV:
	    if (acc_loaded)
		acc_offset -= n->count;

	    jit_addi(REG_P, REG_P, n->count * tape_step);
	    break;

	case T_ADD:
	    load_acc_offset(n->offset);
	    set_acc_offset(n->offset);

	    jit_addi(REG_ACC, REG_ACC, n->count);
	    break;

	case T_SET:
	    set_acc_offset(n->offset);
	    if (acc_const && acc_const_val == n->count) {
		;
	    } else if (acc_const && acc_const_val+1 == n->count) {
		jit_addi(REG_ACC, REG_ACC, 1);
            } else if (acc_const && acc_const_val-1 == n->count) {
		jit_addi(REG_ACC, REG_ACC, -1);
            } else {
		jit_movi(REG_ACC, n->count);
            }
            acc_const = 1;
            acc_const_val = n->count;
            break;

	case T_CALC:
	    if (n->offset == n->offset2 && n->count2 == 1) {
		load_acc_offset(n->offset);
		set_acc_offset(n->offset);
		if (n->count)
		    jit_addi(REG_ACC, REG_ACC, n->count);
	    } else if (n->count2 != 0) {
		load_acc_offset(n->offset2);
		set_acc_offset(n->offset);
		if (n->count2 == -1)
		    jit_negr(REG_ACC, REG_ACC);
		else if (n->count2 != 1)
		    jit_muli(REG_ACC, REG_ACC, n->count2);
		if (n->count)
		    jit_addi(REG_ACC, REG_ACC, n->count);
	    } else {
		clean_acc();
		set_acc_offset(n->offset);

		jit_movi(REG_ACC, n->count);
		if (n->count2 != 0) {
		    if (tape_step > 1)
			jit_ldxi_i(REG_A1, REG_P, n->offset2 * tape_step);
		    else
			jit_ldxi_uc(REG_A1, REG_P, n->offset2);
		    if (n->count2 == -1)
			jit_negr(REG_A1, REG_A1);
		    else if (n->count2 != 1)
			jit_muli(REG_A1, REG_A1, n->count2);
		    jit_addr(REG_ACC, REG_ACC, REG_A1);
		}
	    }

	    if (n->count3 != 0) {
		if (tape_step > 1)
		    jit_ldxi_i(REG_A1, REG_P, n->offset3 * tape_step);
		else
		    jit_ldxi_uc(REG_A1, REG_P, n->offset3);
		if (n->count3 == -1)
		    jit_negr(REG_A1, REG_A1);
		else if (n->count3 != 1)
		    jit_muli(REG_A1, REG_A1, n->count3);
		jit_addr(REG_ACC, REG_ACC, REG_A1);
	    }
	    break;

	case T_IF: case T_MULT: case T_CMULT:
	case T_WHL:
	    load_acc_offset(n->offset);
	    clean_acc();
	    acc_const = acc_loaded = 0;

	    if (stackptr >= maxstack) {
		loopstack = realloc(loopstack,
			    ((maxstack+=32)+2)*sizeof(*loopstack));
		if (loopstack == 0) {
		    perror("loop stack realloc failure");
		    exit(1);
		}
	    }

	    if (cell_mask > 0 && acc_hi_dirty) {
		if (cell_mask == 0xFF)
		    jit_extr_uc(REG_ACC,REG_ACC);
		else
		    jit_andi(REG_ACC, REG_ACC, cell_mask);
	    }

#ifdef GNULIGHTv1
	    loopstack[stackptr] = jit_beqi_i(jit_forward(), REG_ACC, 0);
	    loopstack[stackptr+1] = jit_get_label();
#endif
#ifdef GNULIGHTv2
	    loopstack[stackptr] = jit_beqi(REG_ACC, 0);
	    loopstack[stackptr+1] = jit_label();
#endif
	    stackptr += 2;
	    break;

	case T_END:
	    load_acc_offset(n->offset);
	    clean_acc();

	    stackptr -= 2;
	    if (stackptr < 0) {
		fprintf(stderr, "Code gen failure: Stack pointer negative.\n");
		exit(1);
	    }

	    if (cell_mask > 0 && acc_hi_dirty) {
		if (cell_mask == 0xFF)
		    jit_extr_uc(REG_ACC,REG_ACC);
		else
		    jit_andi(REG_ACC, REG_ACC, cell_mask);
	    }

#ifdef GNULIGHTv1
	    jit_bnei_i(loopstack[stackptr+1], REG_ACC, 0);
	    jit_patch(loopstack[stackptr]);
#endif
#ifdef GNULIGHTv2
	    {
		jit_node_t *ref;
		ref = jit_bnei(REG_ACC, 0);
		jit_patch_at(ref, loopstack[stackptr+1]);
		jit_patch(loopstack[stackptr]);
	    }
#endif
	    break;

	case T_ENDIF:
	    clean_acc();
	    acc_const = acc_loaded = 0;

	    stackptr -= 2;
	    if (stackptr < 0) {
		fprintf(stderr, "Code gen failure: Stack pointer negative.\n");
		exit(1);
	    }
	    jit_patch(loopstack[stackptr]);
	    break;

	case T_PRT:
	    clean_acc();
	    load_acc_offset(n->offset);
	    acc_loaded = 0;

#ifdef GNULIGHTv1
	    jit_prepare_i(1);
	    jit_pusharg_i(REG_ACC);
	    jit_finish(putch);
#endif
#ifdef GNULIGHTv2
	    jit_prepare();
	    jit_pushargr(REG_ACC);
	    jit_finishi(putch);
#endif
	    break;

	case T_CHR:
	    clean_acc();
	    acc_const = acc_loaded = 0;

	    if (n->count <= 0 || (n->count >= 127 && iostyle == 1) ||
		    !n->next || n->next->type != T_CHR) {
		jit_movi(REG_ACC, n->count);
#ifdef GNULIGHTv1
		jit_prepare_i(1);
		jit_pusharg_i(REG_ACC);
		jit_finish(putch);
#endif
#ifdef GNULIGHTv2
		jit_prepare();
		jit_pushargr(REG_ACC);
		jit_finishi(putch);
#endif
	    } else {
		unsigned i = 0;
		struct bfi * v = n;
		char *s;
		while(v->next && v->next->type == T_CHR &&
			v->next->count > 0 &&
			    (v->next->count < 127 || iostyle != 1)) {

		    if (i+2 > maxstrlen) {
			if (maxstrlen) maxstrlen *= 2; else maxstrlen = 4096;
			strbuf = realloc(strbuf, maxstrlen);
			if (!strbuf) {
			    fprintf(stderr, "Reallocate of string buffer failed\n");
			    exit(42);
			}
		    }

		    strbuf[i++] = (char) /*GCC -Wconversion*/ v->count;
		    n = v;
		    v = v->next;
		}
		strbuf[i] = 0;
		s = strdup(strbuf);
		if (!s) {
		    fprintf(stderr, "Save of string failed\n");
		    exit(43);
		}
		save_ptr_for_free(s);

#ifdef GNULIGHTv1
		jit_movi_p(REG_ACC, s);
		jit_prepare_i(1);
		jit_pusharg_i(REG_ACC);
		jit_finish(puts_without_nl);
#endif
#ifdef GNULIGHTv2
		jit_prepare();
		jit_pushargi((jit_word_t) s);
		jit_finishi(puts_without_nl);
#endif
	    }
	    break;

	case T_INP:
	    load_acc_offset(n->offset);
	    set_acc_offset(n->offset);

#ifdef GNULIGHTv1
	    jit_prepare_i(1);
	    jit_pusharg_i(REG_ACC);
	    jit_finish(getch);
	    jit_retval_i(REG_ACC);
#endif
#ifdef GNULIGHTv2
	    jit_prepare();
	    jit_pushargr(REG_ACC);
	    jit_finishi(getch);
	    jit_retval(REG_ACC);
#endif
	    break;

	case T_STOP:
#ifdef GNULIGHTv1
	    jit_prepare_i(0);
	    jit_finish(failout);
#endif
#ifdef GNULIGHTv2
	    jit_prepare();
	    jit_finishi(failout);
#endif
	    break;

	case T_NOP:
	case T_DUMP:
	    fprintf(stderr, "Warning on code generation: "
		    "%s node: ptr+%d, cnt=%d, @(%d,%d).\n",
		    tokennames[n->type],
		    n->offset, n->count, n->line, n->col);
	    break;

	default:
	    fprintf(stderr, "Code gen error: "
		    "%s\t"
		    "%d:%d, %d:%d, %d:%d\n",
		    tokennames[n->type],
		    n->offset, n->count,
		    n->offset2, n->count2,
		    n->offset3, n->count3);
	    exit(1);
	}
	n=n->next;

#if 0 /*def GNULIGHTv2 */
	if(n && enable_trace) {
	    char *p, buf[250];
	    clean_acc();
	    acc_loaded = 0;

	    sprintf(buf, "@(%d,%d)\n", n->line, n->col);
	    p = strdup(buf);
	    save_ptr_for_free(p);

	    jit_prepare();
	    jit_pushargi((jit_word_t) p);
	    jit_finishi(puts_without_nl);
	}
#endif

#ifdef GNULIGHTv1
	/* TODO -- Check for codeBuffer overflow (add jmp to new) */
#endif
    }

    jit_ret();

    if (strbuf) { maxstrlen = 0; free(strbuf); strbuf = 0; }

    delete_tree();

#ifdef GNULIGHTv1
    jit_flush_code(startptr, jit_get_ip().ptr);

    if (verbose)
	fprintf(stderr, "Generated %d bytes of V1 GNU Lightning code, running\n",
		(int)(jit_get_ip().ptr - (char*)startptr));

    start_runclock();
    codeptr(map_hugeram());
    finish_runclock(&run_time, &io_time);
#endif

#ifdef GNULIGHTv2
    jit_epilog();
    end = jit_note(__FILE__, __LINE__);
    codeptr = jit_emit();

    if (verbose)
	fprintf(stderr, "Generated %d bytes of V2 GNU Lightning code, running\n",
	    (int)((char*)jit_address(end) - (char*)jit_address(start)));

    jit_clear_state();
    // jit_disassemble();

    start_runclock();
    codeptr(map_hugeram());
    finish_runclock(&run_time, &io_time);
#endif

#if 0
  /* This code writes the generated instructions to a file
   * so we can disassemble it using:  ndisasm -b 32/64 code.bin  */
    {
#ifdef GNULIGHTv1
	char   *p = startptr;
	int     s = jit_get_ip().ptr - p;
#endif
#ifdef GNULIGHTv2
	char   *p = (char*)jit_address(start);
	int     s = (char*)jit_address(end) - p;
#endif
	FILE   *fp = fopen("code.bin", "w");
	int     i;
	for (i = 0; i < s; ++i) {
	    fputc(p[i], fp);
	}
	fclose(fp);
    }
#endif

#ifdef GNULIGHTv2
    jit_destroy_state();
    finish_jit();
#endif

    codeptr = 0;
    if (loopstack) { free(loopstack); loopstack = 0; }
    free_saved_memory();
}
int scheme_inline_alloc(mz_jit_state *jitter, int amt, Scheme_Type ty, int flags,
			int keep_r0_r1, int keep_fpr1, int inline_retry,
                        int keep_extfpr1)
/* Puts allocated result at JIT_V1; first word is GC tag.
   Uses JIT_R2 as temporary. The allocated memory is "dirty" (i.e., not 0ed).
   Save FP0 when FP ops are enabled. */
{
  GC_CAN_IGNORE jit_insn *ref, *reffail;
#ifdef MZ_GC_STRESS_TESTING
  GC_CAN_IGNORE jit_insn *refstress;
#endif
  intptr_t a_word, sz, algn;

  sz = GC_compute_alloc_size(amt);
  algn = GC_alloc_alignment();

  __START_TINY_JUMPS__(1);
#ifdef MZ_GC_STRESS_TESTING
  refstress = jit_jmpi(jit_forward());
#endif
  reffail = jit_get_ip();
  mz_tl_ldi_p(JIT_V1, tl_GC_gen0_alloc_page_ptr);
  jit_subi_l(JIT_R2, JIT_V1, 1);
  jit_andi_l(JIT_R2, JIT_R2, (algn - 1));
  ref = jit_blti_l(jit_forward(), JIT_R2, (algn - sz));
#ifdef MZ_GC_STRESS_TESTING
  mz_patch_ucbranch(refstress);
#endif
  CHECK_LIMIT();
  __END_TINY_JUMPS__(1);

  /* Failure handling */
  if (inline_retry) {
    int mode;
    if (keep_r0_r1)
      mode = 1;
    else if (keep_fpr1)
      mode = 2;
    else if (keep_extfpr1)
      mode = 3;
    else
      mode = 0;
    scheme_generate_alloc_retry(jitter, mode);
    CHECK_LIMIT();
  } else {
    if (keep_r0_r1) {
      (void)jit_calli(sjc.retry_alloc_code_keep_r0_r1);
    } else if (keep_fpr1) {
      (void)jit_calli(sjc.retry_alloc_code_keep_fpr1);
#ifdef MZ_LONG_DOUBLE
    } else if (keep_extfpr1) {
      (void)jit_calli(sjc.retry_alloc_code_keep_extfpr1);
#endif
    } else {
      (void)jit_calli(sjc.retry_alloc_code);
    }
  }
  __START_TINY_JUMPS__(1);
  (void)jit_jmpi(reffail);
  __END_SHORT_JUMPS__(1);
  
  __START_TINY_JUMPS__(1);
  mz_patch_branch(ref);
  jit_addi_ul(JIT_R2, JIT_V1, sz);
  (void)mz_tl_sti_l(tl_GC_gen0_alloc_page_ptr, JIT_R2, JIT_R0);

  /* GC header: */
  if (ty >= 0) {
    if ((ty == scheme_pair_type)
        || (ty == scheme_mutable_pair_type)
        || (ty == scheme_raw_pair_type))
      a_word = GC_pair_initial_word(amt);
    else
      a_word = GC_initial_word(amt);
    jit_stir_l(JIT_V1, a_word);
    
    /* Scheme_Object header: */
    a_word = initial_tag_word(ty, flags);
    jit_stixi_l(sizeof(intptr_t), JIT_V1, a_word);
  } else {
    /* an array of pointers */
    a_word = GC_array_initial_word(amt);
    jit_stir_l(JIT_V1, a_word);
  }

  CHECK_LIMIT();
  __END_TINY_JUMPS__(1);

  return 1;
}
示例#6
0
int scheme_inline_alloc(mz_jit_state *jitter, int amt, Scheme_Type ty, int immut,
			int keep_r0_r1, int keep_fpr1, int inline_retry)
/* Puts allocated result at JIT_V1; first word is GC tag.
   Uses JIT_R2 as temporary. The allocated memory is "dirty" (i.e., not 0ed).
   Save FP0 when FP ops are enabled. */
{
  GC_CAN_IGNORE jit_insn *ref, *reffail;
  intptr_t a_word, sz, algn;

  sz = GC_compute_alloc_size(amt);
  algn = GC_alloc_alignment();

  __START_TINY_JUMPS__(1);
  reffail = _jit.x.pc;
  mz_tl_ldi_p(JIT_V1, tl_GC_gen0_alloc_page_ptr);
  jit_subi_l(JIT_R2, JIT_V1, 1);
  jit_andi_l(JIT_R2, JIT_R2, (algn - 1));
  ref = jit_blti_l(jit_forward(), JIT_R2, (algn - sz));
  CHECK_LIMIT();
  __END_TINY_JUMPS__(1);

  /* Failure handling */
  if (keep_r0_r1) {
    if (inline_retry) {
      scheme_generate_alloc_retry(jitter, 1);
      CHECK_LIMIT();
    } else {
      (void)jit_calli(sjc.retry_alloc_code_keep_r0_r1);
    }
  } else if (keep_fpr1) {
    (void)jit_calli(sjc.retry_alloc_code_keep_fpr1);
  } else {
    (void)jit_calli(sjc.retry_alloc_code);
  }
  __START_TINY_JUMPS__(1);
  (void)jit_jmpi(reffail);
  __END_SHORT_JUMPS__(1);
  
  __START_TINY_JUMPS__(1);
  mz_patch_branch(ref);
  jit_addi_ul(JIT_R2, JIT_V1, sz);
  (void)mz_tl_sti_l(tl_GC_gen0_alloc_page_ptr, JIT_R2, JIT_R0);

  /* GC header: */
  if (ty >= 0) {
    a_word = GC_initial_word(amt);
    jit_movi_l(JIT_R2, a_word);
    jit_str_l(JIT_V1, JIT_R2);
    
    /* Scheme_Object header: */
    a_word = initial_tag_word(ty, immut);
    jit_movi_l(JIT_R2, a_word);
    jit_stxi_l(sizeof(intptr_t), JIT_V1, JIT_R2);
  } else {
    /* an array of pointers */
    a_word = GC_array_initial_word(amt);
    jit_movi_l(JIT_R2, a_word);
    jit_str_l(JIT_V1, JIT_R2);
  }

  CHECK_LIMIT();
  __END_TINY_JUMPS__(1);

  return 1;
}