xref: /openbmc/linux/drivers/acpi/acpica/exmisc.c (revision 275876e2)
1 /******************************************************************************
2  *
3  * Module Name: exmisc - ACPI AML (p-code) execution - specific opcodes
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2014, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acinterp.h"
47 #include "amlcode.h"
48 #include "amlresrc.h"
49 
50 #define _COMPONENT          ACPI_EXECUTER
51 ACPI_MODULE_NAME("exmisc")
52 
53 /*******************************************************************************
54  *
55  * FUNCTION:    acpi_ex_get_object_reference
56  *
57  * PARAMETERS:  obj_desc            - Create a reference to this object
58  *              return_desc         - Where to store the reference
59  *              walk_state          - Current state
60  *
61  * RETURN:      Status
62  *
63  * DESCRIPTION: Obtain and return a "reference" to the target object
64  *              Common code for the ref_of_op and the cond_ref_of_op.
65  *
66  ******************************************************************************/
67 acpi_status
68 acpi_ex_get_object_reference(union acpi_operand_object *obj_desc,
69 			     union acpi_operand_object **return_desc,
70 			     struct acpi_walk_state *walk_state)
71 {
72 	union acpi_operand_object *reference_obj;
73 	union acpi_operand_object *referenced_obj;
74 
75 	ACPI_FUNCTION_TRACE_PTR(ex_get_object_reference, obj_desc);
76 
77 	*return_desc = NULL;
78 
79 	switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
80 	case ACPI_DESC_TYPE_OPERAND:
81 
82 		if (obj_desc->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
83 			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
84 		}
85 
86 		/*
87 		 * Must be a reference to a Local or Arg
88 		 */
89 		switch (obj_desc->reference.class) {
90 		case ACPI_REFCLASS_LOCAL:
91 		case ACPI_REFCLASS_ARG:
92 		case ACPI_REFCLASS_DEBUG:
93 
94 			/* The referenced object is the pseudo-node for the local/arg */
95 
96 			referenced_obj = obj_desc->reference.object;
97 			break;
98 
99 		default:
100 
101 			ACPI_ERROR((AE_INFO, "Unknown Reference Class 0x%2.2X",
102 				    obj_desc->reference.class));
103 			return_ACPI_STATUS(AE_AML_INTERNAL);
104 		}
105 		break;
106 
107 	case ACPI_DESC_TYPE_NAMED:
108 		/*
109 		 * A named reference that has already been resolved to a Node
110 		 */
111 		referenced_obj = obj_desc;
112 		break;
113 
114 	default:
115 
116 		ACPI_ERROR((AE_INFO, "Invalid descriptor type 0x%X",
117 			    ACPI_GET_DESCRIPTOR_TYPE(obj_desc)));
118 		return_ACPI_STATUS(AE_TYPE);
119 	}
120 
121 	/* Create a new reference object */
122 
123 	reference_obj =
124 	    acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_REFERENCE);
125 	if (!reference_obj) {
126 		return_ACPI_STATUS(AE_NO_MEMORY);
127 	}
128 
129 	reference_obj->reference.class = ACPI_REFCLASS_REFOF;
130 	reference_obj->reference.object = referenced_obj;
131 	*return_desc = reference_obj;
132 
133 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
134 			  "Object %p Type [%s], returning Reference %p\n",
135 			  obj_desc, acpi_ut_get_object_type_name(obj_desc),
136 			  *return_desc));
137 
138 	return_ACPI_STATUS(AE_OK);
139 }
140 
141 /*******************************************************************************
142  *
143  * FUNCTION:    acpi_ex_concat_template
144  *
145  * PARAMETERS:  operand0            - First source object
146  *              operand1            - Second source object
147  *              actual_return_desc  - Where to place the return object
148  *              walk_state          - Current walk state
149  *
150  * RETURN:      Status
151  *
152  * DESCRIPTION: Concatenate two resource templates
153  *
154  ******************************************************************************/
155 
156 acpi_status
157 acpi_ex_concat_template(union acpi_operand_object *operand0,
158 			union acpi_operand_object *operand1,
159 			union acpi_operand_object **actual_return_desc,
160 			struct acpi_walk_state *walk_state)
161 {
162 	acpi_status status;
163 	union acpi_operand_object *return_desc;
164 	u8 *new_buf;
165 	u8 *end_tag;
166 	acpi_size length0;
167 	acpi_size length1;
168 	acpi_size new_length;
169 
170 	ACPI_FUNCTION_TRACE(ex_concat_template);
171 
172 	/*
173 	 * Find the end_tag descriptor in each resource template.
174 	 * Note1: returned pointers point TO the end_tag, not past it.
175 	 * Note2: zero-length buffers are allowed; treated like one end_tag
176 	 */
177 
178 	/* Get the length of the first resource template */
179 
180 	status = acpi_ut_get_resource_end_tag(operand0, &end_tag);
181 	if (ACPI_FAILURE(status)) {
182 		return_ACPI_STATUS(status);
183 	}
184 
185 	length0 = ACPI_PTR_DIFF(end_tag, operand0->buffer.pointer);
186 
187 	/* Get the length of the second resource template */
188 
189 	status = acpi_ut_get_resource_end_tag(operand1, &end_tag);
190 	if (ACPI_FAILURE(status)) {
191 		return_ACPI_STATUS(status);
192 	}
193 
194 	length1 = ACPI_PTR_DIFF(end_tag, operand1->buffer.pointer);
195 
196 	/* Combine both lengths, minimum size will be 2 for end_tag */
197 
198 	new_length = length0 + length1 + sizeof(struct aml_resource_end_tag);
199 
200 	/* Create a new buffer object for the result (with one end_tag) */
201 
202 	return_desc = acpi_ut_create_buffer_object(new_length);
203 	if (!return_desc) {
204 		return_ACPI_STATUS(AE_NO_MEMORY);
205 	}
206 
207 	/*
208 	 * Copy the templates to the new buffer, 0 first, then 1 follows. One
209 	 * end_tag descriptor is copied from Operand1.
210 	 */
211 	new_buf = return_desc->buffer.pointer;
212 	ACPI_MEMCPY(new_buf, operand0->buffer.pointer, length0);
213 	ACPI_MEMCPY(new_buf + length0, operand1->buffer.pointer, length1);
214 
215 	/* Insert end_tag and set the checksum to zero, means "ignore checksum" */
216 
217 	new_buf[new_length - 1] = 0;
218 	new_buf[new_length - 2] = ACPI_RESOURCE_NAME_END_TAG | 1;
219 
220 	/* Return the completed resource template */
221 
222 	*actual_return_desc = return_desc;
223 	return_ACPI_STATUS(AE_OK);
224 }
225 
226 /*******************************************************************************
227  *
228  * FUNCTION:    acpi_ex_do_concatenate
229  *
230  * PARAMETERS:  operand0            - First source object
231  *              operand1            - Second source object
232  *              actual_return_desc  - Where to place the return object
233  *              walk_state          - Current walk state
234  *
235  * RETURN:      Status
236  *
237  * DESCRIPTION: Concatenate two objects OF THE SAME TYPE.
238  *
239  ******************************************************************************/
240 
241 acpi_status
242 acpi_ex_do_concatenate(union acpi_operand_object *operand0,
243 		       union acpi_operand_object *operand1,
244 		       union acpi_operand_object **actual_return_desc,
245 		       struct acpi_walk_state *walk_state)
246 {
247 	union acpi_operand_object *local_operand1 = operand1;
248 	union acpi_operand_object *return_desc;
249 	char *new_buf;
250 	acpi_status status;
251 
252 	ACPI_FUNCTION_TRACE(ex_do_concatenate);
253 
254 	/*
255 	 * Convert the second operand if necessary. The first operand
256 	 * determines the type of the second operand, (See the Data Types
257 	 * section of the ACPI specification.)  Both object types are
258 	 * guaranteed to be either Integer/String/Buffer by the operand
259 	 * resolution mechanism.
260 	 */
261 	switch (operand0->common.type) {
262 	case ACPI_TYPE_INTEGER:
263 
264 		status =
265 		    acpi_ex_convert_to_integer(operand1, &local_operand1, 16);
266 		break;
267 
268 	case ACPI_TYPE_STRING:
269 
270 		status = acpi_ex_convert_to_string(operand1, &local_operand1,
271 						   ACPI_IMPLICIT_CONVERT_HEX);
272 		break;
273 
274 	case ACPI_TYPE_BUFFER:
275 
276 		status = acpi_ex_convert_to_buffer(operand1, &local_operand1);
277 		break;
278 
279 	default:
280 
281 		ACPI_ERROR((AE_INFO, "Invalid object type: 0x%X",
282 			    operand0->common.type));
283 		status = AE_AML_INTERNAL;
284 	}
285 
286 	if (ACPI_FAILURE(status)) {
287 		goto cleanup;
288 	}
289 
290 	/*
291 	 * Both operands are now known to be the same object type
292 	 * (Both are Integer, String, or Buffer), and we can now perform the
293 	 * concatenation.
294 	 */
295 
296 	/*
297 	 * There are three cases to handle:
298 	 *
299 	 * 1) Two Integers concatenated to produce a new Buffer
300 	 * 2) Two Strings concatenated to produce a new String
301 	 * 3) Two Buffers concatenated to produce a new Buffer
302 	 */
303 	switch (operand0->common.type) {
304 	case ACPI_TYPE_INTEGER:
305 
306 		/* Result of two Integers is a Buffer */
307 		/* Need enough buffer space for two integers */
308 
309 		return_desc = acpi_ut_create_buffer_object((acpi_size)
310 							   ACPI_MUL_2
311 							   (acpi_gbl_integer_byte_width));
312 		if (!return_desc) {
313 			status = AE_NO_MEMORY;
314 			goto cleanup;
315 		}
316 
317 		new_buf = (char *)return_desc->buffer.pointer;
318 
319 		/* Copy the first integer, LSB first */
320 
321 		ACPI_MEMCPY(new_buf, &operand0->integer.value,
322 			    acpi_gbl_integer_byte_width);
323 
324 		/* Copy the second integer (LSB first) after the first */
325 
326 		ACPI_MEMCPY(new_buf + acpi_gbl_integer_byte_width,
327 			    &local_operand1->integer.value,
328 			    acpi_gbl_integer_byte_width);
329 		break;
330 
331 	case ACPI_TYPE_STRING:
332 
333 		/* Result of two Strings is a String */
334 
335 		return_desc = acpi_ut_create_string_object(((acpi_size)
336 							    operand0->string.
337 							    length +
338 							    local_operand1->
339 							    string.length));
340 		if (!return_desc) {
341 			status = AE_NO_MEMORY;
342 			goto cleanup;
343 		}
344 
345 		new_buf = return_desc->string.pointer;
346 
347 		/* Concatenate the strings */
348 
349 		ACPI_STRCPY(new_buf, operand0->string.pointer);
350 		ACPI_STRCPY(new_buf + operand0->string.length,
351 			    local_operand1->string.pointer);
352 		break;
353 
354 	case ACPI_TYPE_BUFFER:
355 
356 		/* Result of two Buffers is a Buffer */
357 
358 		return_desc = acpi_ut_create_buffer_object(((acpi_size)
359 							    operand0->buffer.
360 							    length +
361 							    local_operand1->
362 							    buffer.length));
363 		if (!return_desc) {
364 			status = AE_NO_MEMORY;
365 			goto cleanup;
366 		}
367 
368 		new_buf = (char *)return_desc->buffer.pointer;
369 
370 		/* Concatenate the buffers */
371 
372 		ACPI_MEMCPY(new_buf, operand0->buffer.pointer,
373 			    operand0->buffer.length);
374 		ACPI_MEMCPY(new_buf + operand0->buffer.length,
375 			    local_operand1->buffer.pointer,
376 			    local_operand1->buffer.length);
377 		break;
378 
379 	default:
380 
381 		/* Invalid object type, should not happen here */
382 
383 		ACPI_ERROR((AE_INFO, "Invalid object type: 0x%X",
384 			    operand0->common.type));
385 		status = AE_AML_INTERNAL;
386 		goto cleanup;
387 	}
388 
389 	*actual_return_desc = return_desc;
390 
391 cleanup:
392 	if (local_operand1 != operand1) {
393 		acpi_ut_remove_reference(local_operand1);
394 	}
395 	return_ACPI_STATUS(status);
396 }
397 
398 /*******************************************************************************
399  *
400  * FUNCTION:    acpi_ex_do_math_op
401  *
402  * PARAMETERS:  opcode              - AML opcode
403  *              integer0            - Integer operand #0
404  *              integer1            - Integer operand #1
405  *
406  * RETURN:      Integer result of the operation
407  *
408  * DESCRIPTION: Execute a math AML opcode. The purpose of having all of the
409  *              math functions here is to prevent a lot of pointer dereferencing
410  *              to obtain the operands.
411  *
412  ******************************************************************************/
413 
414 u64 acpi_ex_do_math_op(u16 opcode, u64 integer0, u64 integer1)
415 {
416 
417 	ACPI_FUNCTION_ENTRY();
418 
419 	switch (opcode) {
420 	case AML_ADD_OP:	/* Add (Integer0, Integer1, Result) */
421 
422 		return (integer0 + integer1);
423 
424 	case AML_BIT_AND_OP:	/* And (Integer0, Integer1, Result) */
425 
426 		return (integer0 & integer1);
427 
428 	case AML_BIT_NAND_OP:	/* NAnd (Integer0, Integer1, Result) */
429 
430 		return (~(integer0 & integer1));
431 
432 	case AML_BIT_OR_OP:	/* Or (Integer0, Integer1, Result) */
433 
434 		return (integer0 | integer1);
435 
436 	case AML_BIT_NOR_OP:	/* NOr (Integer0, Integer1, Result) */
437 
438 		return (~(integer0 | integer1));
439 
440 	case AML_BIT_XOR_OP:	/* XOr (Integer0, Integer1, Result) */
441 
442 		return (integer0 ^ integer1);
443 
444 	case AML_MULTIPLY_OP:	/* Multiply (Integer0, Integer1, Result) */
445 
446 		return (integer0 * integer1);
447 
448 	case AML_SHIFT_LEFT_OP:	/* shift_left (Operand, shift_count, Result) */
449 
450 		/*
451 		 * We need to check if the shiftcount is larger than the integer bit
452 		 * width since the behavior of this is not well-defined in the C language.
453 		 */
454 		if (integer1 >= acpi_gbl_integer_bit_width) {
455 			return (0);
456 		}
457 		return (integer0 << integer1);
458 
459 	case AML_SHIFT_RIGHT_OP:	/* shift_right (Operand, shift_count, Result) */
460 
461 		/*
462 		 * We need to check if the shiftcount is larger than the integer bit
463 		 * width since the behavior of this is not well-defined in the C language.
464 		 */
465 		if (integer1 >= acpi_gbl_integer_bit_width) {
466 			return (0);
467 		}
468 		return (integer0 >> integer1);
469 
470 	case AML_SUBTRACT_OP:	/* Subtract (Integer0, Integer1, Result) */
471 
472 		return (integer0 - integer1);
473 
474 	default:
475 
476 		return (0);
477 	}
478 }
479 
480 /*******************************************************************************
481  *
482  * FUNCTION:    acpi_ex_do_logical_numeric_op
483  *
484  * PARAMETERS:  opcode              - AML opcode
485  *              integer0            - Integer operand #0
486  *              integer1            - Integer operand #1
487  *              logical_result      - TRUE/FALSE result of the operation
488  *
489  * RETURN:      Status
490  *
491  * DESCRIPTION: Execute a logical "Numeric" AML opcode. For these Numeric
492  *              operators (LAnd and LOr), both operands must be integers.
493  *
494  *              Note: cleanest machine code seems to be produced by the code
495  *              below, rather than using statements of the form:
496  *                  Result = (Integer0 && Integer1);
497  *
498  ******************************************************************************/
499 
500 acpi_status
501 acpi_ex_do_logical_numeric_op(u16 opcode,
502 			      u64 integer0, u64 integer1, u8 *logical_result)
503 {
504 	acpi_status status = AE_OK;
505 	u8 local_result = FALSE;
506 
507 	ACPI_FUNCTION_TRACE(ex_do_logical_numeric_op);
508 
509 	switch (opcode) {
510 	case AML_LAND_OP:	/* LAnd (Integer0, Integer1) */
511 
512 		if (integer0 && integer1) {
513 			local_result = TRUE;
514 		}
515 		break;
516 
517 	case AML_LOR_OP:	/* LOr (Integer0, Integer1) */
518 
519 		if (integer0 || integer1) {
520 			local_result = TRUE;
521 		}
522 		break;
523 
524 	default:
525 
526 		status = AE_AML_INTERNAL;
527 		break;
528 	}
529 
530 	/* Return the logical result and status */
531 
532 	*logical_result = local_result;
533 	return_ACPI_STATUS(status);
534 }
535 
536 /*******************************************************************************
537  *
538  * FUNCTION:    acpi_ex_do_logical_op
539  *
540  * PARAMETERS:  opcode              - AML opcode
541  *              operand0            - operand #0
542  *              operand1            - operand #1
543  *              logical_result      - TRUE/FALSE result of the operation
544  *
545  * RETURN:      Status
546  *
547  * DESCRIPTION: Execute a logical AML opcode. The purpose of having all of the
548  *              functions here is to prevent a lot of pointer dereferencing
549  *              to obtain the operands and to simplify the generation of the
550  *              logical value. For the Numeric operators (LAnd and LOr), both
551  *              operands must be integers. For the other logical operators,
552  *              operands can be any combination of Integer/String/Buffer. The
553  *              first operand determines the type to which the second operand
554  *              will be converted.
555  *
556  *              Note: cleanest machine code seems to be produced by the code
557  *              below, rather than using statements of the form:
558  *                  Result = (Operand0 == Operand1);
559  *
560  ******************************************************************************/
561 
562 acpi_status
563 acpi_ex_do_logical_op(u16 opcode,
564 		      union acpi_operand_object *operand0,
565 		      union acpi_operand_object *operand1, u8 * logical_result)
566 {
567 	union acpi_operand_object *local_operand1 = operand1;
568 	u64 integer0;
569 	u64 integer1;
570 	u32 length0;
571 	u32 length1;
572 	acpi_status status = AE_OK;
573 	u8 local_result = FALSE;
574 	int compare;
575 
576 	ACPI_FUNCTION_TRACE(ex_do_logical_op);
577 
578 	/*
579 	 * Convert the second operand if necessary. The first operand
580 	 * determines the type of the second operand, (See the Data Types
581 	 * section of the ACPI 3.0+ specification.)  Both object types are
582 	 * guaranteed to be either Integer/String/Buffer by the operand
583 	 * resolution mechanism.
584 	 */
585 	switch (operand0->common.type) {
586 	case ACPI_TYPE_INTEGER:
587 
588 		status =
589 		    acpi_ex_convert_to_integer(operand1, &local_operand1, 16);
590 		break;
591 
592 	case ACPI_TYPE_STRING:
593 
594 		status = acpi_ex_convert_to_string(operand1, &local_operand1,
595 						   ACPI_IMPLICIT_CONVERT_HEX);
596 		break;
597 
598 	case ACPI_TYPE_BUFFER:
599 
600 		status = acpi_ex_convert_to_buffer(operand1, &local_operand1);
601 		break;
602 
603 	default:
604 
605 		status = AE_AML_INTERNAL;
606 		break;
607 	}
608 
609 	if (ACPI_FAILURE(status)) {
610 		goto cleanup;
611 	}
612 
613 	/*
614 	 * Two cases: 1) Both Integers, 2) Both Strings or Buffers
615 	 */
616 	if (operand0->common.type == ACPI_TYPE_INTEGER) {
617 		/*
618 		 * 1) Both operands are of type integer
619 		 *    Note: local_operand1 may have changed above
620 		 */
621 		integer0 = operand0->integer.value;
622 		integer1 = local_operand1->integer.value;
623 
624 		switch (opcode) {
625 		case AML_LEQUAL_OP:	/* LEqual (Operand0, Operand1) */
626 
627 			if (integer0 == integer1) {
628 				local_result = TRUE;
629 			}
630 			break;
631 
632 		case AML_LGREATER_OP:	/* LGreater (Operand0, Operand1) */
633 
634 			if (integer0 > integer1) {
635 				local_result = TRUE;
636 			}
637 			break;
638 
639 		case AML_LLESS_OP:	/* LLess (Operand0, Operand1) */
640 
641 			if (integer0 < integer1) {
642 				local_result = TRUE;
643 			}
644 			break;
645 
646 		default:
647 
648 			status = AE_AML_INTERNAL;
649 			break;
650 		}
651 	} else {
652 		/*
653 		 * 2) Both operands are Strings or both are Buffers
654 		 *    Note: Code below takes advantage of common Buffer/String
655 		 *          object fields. local_operand1 may have changed above. Use
656 		 *          memcmp to handle nulls in buffers.
657 		 */
658 		length0 = operand0->buffer.length;
659 		length1 = local_operand1->buffer.length;
660 
661 		/* Lexicographic compare: compare the data bytes */
662 
663 		compare = ACPI_MEMCMP(operand0->buffer.pointer,
664 				      local_operand1->buffer.pointer,
665 				      (length0 > length1) ? length1 : length0);
666 
667 		switch (opcode) {
668 		case AML_LEQUAL_OP:	/* LEqual (Operand0, Operand1) */
669 
670 			/* Length and all bytes must be equal */
671 
672 			if ((length0 == length1) && (compare == 0)) {
673 
674 				/* Length and all bytes match ==> TRUE */
675 
676 				local_result = TRUE;
677 			}
678 			break;
679 
680 		case AML_LGREATER_OP:	/* LGreater (Operand0, Operand1) */
681 
682 			if (compare > 0) {
683 				local_result = TRUE;
684 				goto cleanup;	/* TRUE */
685 			}
686 			if (compare < 0) {
687 				goto cleanup;	/* FALSE */
688 			}
689 
690 			/* Bytes match (to shortest length), compare lengths */
691 
692 			if (length0 > length1) {
693 				local_result = TRUE;
694 			}
695 			break;
696 
697 		case AML_LLESS_OP:	/* LLess (Operand0, Operand1) */
698 
699 			if (compare > 0) {
700 				goto cleanup;	/* FALSE */
701 			}
702 			if (compare < 0) {
703 				local_result = TRUE;
704 				goto cleanup;	/* TRUE */
705 			}
706 
707 			/* Bytes match (to shortest length), compare lengths */
708 
709 			if (length0 < length1) {
710 				local_result = TRUE;
711 			}
712 			break;
713 
714 		default:
715 
716 			status = AE_AML_INTERNAL;
717 			break;
718 		}
719 	}
720 
721 cleanup:
722 
723 	/* New object was created if implicit conversion performed - delete */
724 
725 	if (local_operand1 != operand1) {
726 		acpi_ut_remove_reference(local_operand1);
727 	}
728 
729 	/* Return the logical result and status */
730 
731 	*logical_result = local_result;
732 	return_ACPI_STATUS(status);
733 }
734