2008-03-16 Ralf Wildenhues <Ralf.Wildenhues@gmx.de>
[binutils.git] / include / xtensa-isa.h
blobc4e31ed7ff6c6ab1f7efe15f27e320c99622a250
1 /* Interface definition for configurable Xtensa ISA support.
2 Copyright 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
4 This file is part of BFD, the Binary File Descriptor library.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
20 #ifndef XTENSA_LIBISA_H
21 #define XTENSA_LIBISA_H
23 #ifdef __cplusplus
24 extern "C" {
25 #endif
27 /* Version number: This is intended to help support code that works with
28 versions of this library from multiple Xtensa releases. */
30 #define XTENSA_ISA_VERSION 7000
32 #ifndef uint32
33 #define uint32 unsigned int
34 #endif
36 /* This file defines the interface to the Xtensa ISA library. This
37 library contains most of the ISA-specific information for a
38 particular Xtensa processor. For example, the set of valid
39 instructions, their opcode encodings and operand fields are all
40 included here.
42 This interface basically defines a number of abstract data types.
44 . an instruction buffer - for holding the raw instruction bits
45 . ISA info - information about the ISA as a whole
46 . instruction formats - instruction size and slot structure
47 . opcodes - information about individual instructions
48 . operands - information about register and immediate instruction operands
49 . stateOperands - information about processor state instruction operands
50 . interfaceOperands - information about interface instruction operands
51 . register files - register file information
52 . processor states - internal processor state information
53 . system registers - "special registers" and "user registers"
54 . interfaces - TIE interfaces that are external to the processor
55 . functional units - TIE shared functions
57 The interface defines a set of functions to access each data type.
58 With the exception of the instruction buffer, the internal
59 representations of the data structures are hidden. All accesses must
60 be made through the functions defined here. */
62 typedef struct xtensa_isa_opaque { int unused; } *xtensa_isa;
65 /* Most of the Xtensa ISA entities (e.g., opcodes, regfiles, etc.) are
66 represented here using sequential integers beginning with 0. The
67 specific values are only fixed for a particular instantiation of an
68 xtensa_isa structure, so these values should only be used
69 internally. */
71 typedef int xtensa_opcode;
72 typedef int xtensa_format;
73 typedef int xtensa_regfile;
74 typedef int xtensa_state;
75 typedef int xtensa_sysreg;
76 typedef int xtensa_interface;
77 typedef int xtensa_funcUnit;
80 /* Define a unique value for undefined items. */
82 #define XTENSA_UNDEFINED -1
85 /* Overview of using this interface to decode/encode instructions:
87 Each Xtensa instruction is associated with a particular instruction
88 format, where the format defines a fixed number of slots for
89 operations. The formats for the core Xtensa ISA have only one slot,
90 but FLIX instructions may have multiple slots. Within each slot,
91 there is a single opcode and some number of associated operands.
93 The encoding and decoding functions operate on instruction buffers,
94 not on the raw bytes of the instructions. The same instruction
95 buffer data structure is used for both entire instructions and
96 individual slots in those instructions -- the contents of a slot need
97 to be extracted from or inserted into the buffer for the instruction
98 as a whole.
100 Decoding an instruction involves first finding the format, which
101 identifies the number of slots, and then decoding each slot
102 separately. A slot is decoded by finding the opcode and then using
103 the opcode to determine how many operands there are. For example:
105 xtensa_insnbuf_from_chars
106 xtensa_format_decode
107 for each slot {
108 xtensa_format_get_slot
109 xtensa_opcode_decode
110 for each operand {
111 xtensa_operand_get_field
112 xtensa_operand_decode
116 Encoding an instruction is roughly the same procedure in reverse:
118 xtensa_format_encode
119 for each slot {
120 xtensa_opcode_encode
121 for each operand {
122 xtensa_operand_encode
123 xtensa_operand_set_field
125 xtensa_format_set_slot
127 xtensa_insnbuf_to_chars
131 /* Error handling. */
133 /* Error codes. The code for the most recent error condition can be
134 retrieved with the "errno" function. For any result other than
135 xtensa_isa_ok, an error message containing additional information
136 about the problem can be retrieved using the "error_msg" function.
137 The error messages are stored in an internal buffer, which should
138 not be freed and may be overwritten by subsequent operations. */
140 typedef enum xtensa_isa_status_enum
142 xtensa_isa_ok = 0,
143 xtensa_isa_bad_format,
144 xtensa_isa_bad_slot,
145 xtensa_isa_bad_opcode,
146 xtensa_isa_bad_operand,
147 xtensa_isa_bad_field,
148 xtensa_isa_bad_iclass,
149 xtensa_isa_bad_regfile,
150 xtensa_isa_bad_sysreg,
151 xtensa_isa_bad_state,
152 xtensa_isa_bad_interface,
153 xtensa_isa_bad_funcUnit,
154 xtensa_isa_wrong_slot,
155 xtensa_isa_no_field,
156 xtensa_isa_out_of_memory,
157 xtensa_isa_buffer_overflow,
158 xtensa_isa_internal_error,
159 xtensa_isa_bad_value
160 } xtensa_isa_status;
162 extern xtensa_isa_status
163 xtensa_isa_errno (xtensa_isa isa);
165 extern char *
166 xtensa_isa_error_msg (xtensa_isa isa);
170 /* Instruction buffers. */
172 typedef uint32 xtensa_insnbuf_word;
173 typedef xtensa_insnbuf_word *xtensa_insnbuf;
176 /* Get the size in "insnbuf_words" of the xtensa_insnbuf array. */
178 extern int
179 xtensa_insnbuf_size (xtensa_isa isa);
182 /* Allocate an xtensa_insnbuf of the right size. */
184 extern xtensa_insnbuf
185 xtensa_insnbuf_alloc (xtensa_isa isa);
188 /* Release an xtensa_insnbuf. */
190 extern void
191 xtensa_insnbuf_free (xtensa_isa isa, xtensa_insnbuf buf);
194 /* Conversion between raw memory (char arrays) and our internal
195 instruction representation. This is complicated by the Xtensa ISA's
196 variable instruction lengths. When converting to chars, the buffer
197 must contain a valid instruction so we know how many bytes to copy;
198 thus, the "to_chars" function returns the number of bytes copied or
199 XTENSA_UNDEFINED on error. The "from_chars" function first reads the
200 minimal number of bytes required to decode the instruction length and
201 then proceeds to copy the entire instruction into the buffer; if the
202 memory does not contain a valid instruction, it copies the maximum
203 number of bytes required for the longest Xtensa instruction. The
204 "num_chars" argument may be used to limit the number of bytes that
205 can be read or written. Otherwise, if "num_chars" is zero, the
206 functions may read or write past the end of the code. */
208 extern int
209 xtensa_insnbuf_to_chars (xtensa_isa isa, const xtensa_insnbuf insn,
210 unsigned char *cp, int num_chars);
212 extern void
213 xtensa_insnbuf_from_chars (xtensa_isa isa, xtensa_insnbuf insn,
214 const unsigned char *cp, int num_chars);
218 /* ISA information. */
220 /* Initialize the ISA information. */
222 extern xtensa_isa
223 xtensa_isa_init (xtensa_isa_status *errno_p, char **error_msg_p);
226 /* Deallocate an xtensa_isa structure. */
228 extern void
229 xtensa_isa_free (xtensa_isa isa);
232 /* Get the maximum instruction size in bytes. */
234 extern int
235 xtensa_isa_maxlength (xtensa_isa isa);
238 /* Decode the length in bytes of an instruction in raw memory (not an
239 insnbuf). This function reads only the minimal number of bytes
240 required to decode the instruction length. Returns
241 XTENSA_UNDEFINED on error. */
243 extern int
244 xtensa_isa_length_from_chars (xtensa_isa isa, const unsigned char *cp);
247 /* Get the number of stages in the processor's pipeline. The pipeline
248 stage values returned by other functions in this library will range
249 from 0 to N-1, where N is the value returned by this function.
250 Note that the stage numbers used here may not correspond to the
251 actual processor hardware, e.g., the hardware may have additional
252 stages before stage 0. Returns XTENSA_UNDEFINED on error. */
254 extern int
255 xtensa_isa_num_pipe_stages (xtensa_isa isa);
258 /* Get the number of various entities that are defined for this processor. */
260 extern int
261 xtensa_isa_num_formats (xtensa_isa isa);
263 extern int
264 xtensa_isa_num_opcodes (xtensa_isa isa);
266 extern int
267 xtensa_isa_num_regfiles (xtensa_isa isa);
269 extern int
270 xtensa_isa_num_states (xtensa_isa isa);
272 extern int
273 xtensa_isa_num_sysregs (xtensa_isa isa);
275 extern int
276 xtensa_isa_num_interfaces (xtensa_isa isa);
278 extern int
279 xtensa_isa_num_funcUnits (xtensa_isa isa);
283 /* Instruction formats. */
285 /* Get the name of a format. Returns null on error. */
287 extern const char *
288 xtensa_format_name (xtensa_isa isa, xtensa_format fmt);
291 /* Given a format name, return the format number. Returns
292 XTENSA_UNDEFINED if the name is not a valid format. */
294 extern xtensa_format
295 xtensa_format_lookup (xtensa_isa isa, const char *fmtname);
298 /* Decode the instruction format from a binary instruction buffer.
299 Returns XTENSA_UNDEFINED if the format is not recognized. */
301 extern xtensa_format
302 xtensa_format_decode (xtensa_isa isa, const xtensa_insnbuf insn);
305 /* Set the instruction format field(s) in a binary instruction buffer.
306 All the other fields are set to zero. Returns non-zero on error. */
308 extern int
309 xtensa_format_encode (xtensa_isa isa, xtensa_format fmt, xtensa_insnbuf insn);
312 /* Find the length (in bytes) of an instruction. Returns
313 XTENSA_UNDEFINED on error. */
315 extern int
316 xtensa_format_length (xtensa_isa isa, xtensa_format fmt);
319 /* Get the number of slots in an instruction. Returns XTENSA_UNDEFINED
320 on error. */
322 extern int
323 xtensa_format_num_slots (xtensa_isa isa, xtensa_format fmt);
326 /* Get the opcode for a no-op in a particular slot.
327 Returns XTENSA_UNDEFINED on error. */
329 extern xtensa_opcode
330 xtensa_format_slot_nop_opcode (xtensa_isa isa, xtensa_format fmt, int slot);
333 /* Get the bits for a specified slot out of an insnbuf for the
334 instruction as a whole and put them into an insnbuf for that one
335 slot, and do the opposite to set a slot. Return non-zero on error. */
337 extern int
338 xtensa_format_get_slot (xtensa_isa isa, xtensa_format fmt, int slot,
339 const xtensa_insnbuf insn, xtensa_insnbuf slotbuf);
341 extern int
342 xtensa_format_set_slot (xtensa_isa isa, xtensa_format fmt, int slot,
343 xtensa_insnbuf insn, const xtensa_insnbuf slotbuf);
347 /* Opcode information. */
349 /* Translate a mnemonic name to an opcode. Returns XTENSA_UNDEFINED if
350 the name is not a valid opcode mnemonic. */
352 extern xtensa_opcode
353 xtensa_opcode_lookup (xtensa_isa isa, const char *opname);
356 /* Decode the opcode for one instruction slot from a binary instruction
357 buffer. Returns the opcode or XTENSA_UNDEFINED if the opcode is
358 illegal. */
360 extern xtensa_opcode
361 xtensa_opcode_decode (xtensa_isa isa, xtensa_format fmt, int slot,
362 const xtensa_insnbuf slotbuf);
365 /* Set the opcode field(s) for an instruction slot. All other fields
366 in the slot are set to zero. Returns non-zero if the opcode cannot
367 be encoded. */
369 extern int
370 xtensa_opcode_encode (xtensa_isa isa, xtensa_format fmt, int slot,
371 xtensa_insnbuf slotbuf, xtensa_opcode opc);
374 /* Get the mnemonic name for an opcode. Returns null on error. */
376 extern const char *
377 xtensa_opcode_name (xtensa_isa isa, xtensa_opcode opc);
380 /* Check various properties of opcodes. These functions return 0 if
381 the condition is false, 1 if the condition is true, and
382 XTENSA_UNDEFINED on error. The instructions are classified as
383 follows:
385 branch: conditional branch; may fall through to next instruction (B*)
386 jump: unconditional branch (J, JX, RET*, RF*)
387 loop: zero-overhead loop (LOOP*)
388 call: unconditional call; control returns to next instruction (CALL*)
390 For the opcodes that affect control flow in some way, the branch
391 target may be specified by an immediate operand or it may be an
392 address stored in a register. You can distinguish these by
393 checking if the instruction has a PC-relative immediate
394 operand. */
396 extern int
397 xtensa_opcode_is_branch (xtensa_isa isa, xtensa_opcode opc);
399 extern int
400 xtensa_opcode_is_jump (xtensa_isa isa, xtensa_opcode opc);
402 extern int
403 xtensa_opcode_is_loop (xtensa_isa isa, xtensa_opcode opc);
405 extern int
406 xtensa_opcode_is_call (xtensa_isa isa, xtensa_opcode opc);
409 /* Find the number of ordinary operands, state operands, and interface
410 operands for an instruction. These return XTENSA_UNDEFINED on
411 error. */
413 extern int
414 xtensa_opcode_num_operands (xtensa_isa isa, xtensa_opcode opc);
416 extern int
417 xtensa_opcode_num_stateOperands (xtensa_isa isa, xtensa_opcode opc);
419 extern int
420 xtensa_opcode_num_interfaceOperands (xtensa_isa isa, xtensa_opcode opc);
423 /* Get functional unit usage requirements for an opcode. Each "use"
424 is identified by a <functional unit, pipeline stage> pair. The
425 "num_funcUnit_uses" function returns the number of these "uses" or
426 XTENSA_UNDEFINED on error. The "funcUnit_use" function returns
427 a pointer to a "use" pair or null on error. */
429 typedef struct xtensa_funcUnit_use_struct
431 xtensa_funcUnit unit;
432 int stage;
433 } xtensa_funcUnit_use;
435 extern int
436 xtensa_opcode_num_funcUnit_uses (xtensa_isa isa, xtensa_opcode opc);
438 extern xtensa_funcUnit_use *
439 xtensa_opcode_funcUnit_use (xtensa_isa isa, xtensa_opcode opc, int u);
443 /* Operand information. */
445 /* Get the name of an operand. Returns null on error. */
447 extern const char *
448 xtensa_operand_name (xtensa_isa isa, xtensa_opcode opc, int opnd);
451 /* Some operands are "invisible", i.e., not explicitly specified in
452 assembly language. When assembling an instruction, you need not set
453 the values of invisible operands, since they are either hardwired or
454 derived from other field values. The values of invisible operands
455 can be examined in the same way as other operands, but remember that
456 an invisible operand may get its value from another visible one, so
457 the entire instruction must be available before examining the
458 invisible operand values. This function returns 1 if an operand is
459 visible, 0 if it is invisible, or XTENSA_UNDEFINED on error. Note
460 that whether an operand is visible is orthogonal to whether it is
461 "implicit", i.e., whether it is encoded in a field in the
462 instruction. */
464 extern int
465 xtensa_operand_is_visible (xtensa_isa isa, xtensa_opcode opc, int opnd);
468 /* Check if an operand is an input ('i'), output ('o'), or inout ('m')
469 operand. Note: The output operand of a conditional assignment
470 (e.g., movnez) appears here as an inout ('m') even if it is declared
471 in the TIE code as an output ('o'); this allows the compiler to
472 properly handle register allocation for conditional assignments.
473 Returns 0 on error. */
475 extern char
476 xtensa_operand_inout (xtensa_isa isa, xtensa_opcode opc, int opnd);
479 /* Get and set the raw (encoded) value of the field for the specified
480 operand. The "set" function does not check if the value fits in the
481 field; that is done by the "encode" function below. Both of these
482 functions return non-zero on error, e.g., if the field is not defined
483 for the specified slot. */
485 extern int
486 xtensa_operand_get_field (xtensa_isa isa, xtensa_opcode opc, int opnd,
487 xtensa_format fmt, int slot,
488 const xtensa_insnbuf slotbuf, uint32 *valp);
490 extern int
491 xtensa_operand_set_field (xtensa_isa isa, xtensa_opcode opc, int opnd,
492 xtensa_format fmt, int slot,
493 xtensa_insnbuf slotbuf, uint32 val);
496 /* Encode and decode operands. The raw bits in the operand field may
497 be encoded in a variety of different ways. These functions hide
498 the details of that encoding. The result values are returned through
499 the argument pointer. The return value is non-zero on error. */
501 extern int
502 xtensa_operand_encode (xtensa_isa isa, xtensa_opcode opc, int opnd,
503 uint32 *valp);
505 extern int
506 xtensa_operand_decode (xtensa_isa isa, xtensa_opcode opc, int opnd,
507 uint32 *valp);
510 /* An operand may be either a register operand or an immediate of some
511 sort (e.g., PC-relative or not). The "is_register" function returns
512 0 if the operand is an immediate, 1 if it is a register, and
513 XTENSA_UNDEFINED on error. The "regfile" function returns the
514 regfile for a register operand, or XTENSA_UNDEFINED on error. */
516 extern int
517 xtensa_operand_is_register (xtensa_isa isa, xtensa_opcode opc, int opnd);
519 extern xtensa_regfile
520 xtensa_operand_regfile (xtensa_isa isa, xtensa_opcode opc, int opnd);
523 /* Register operands may span multiple consecutive registers, e.g., a
524 64-bit data type may occupy two 32-bit registers. Only the first
525 register is encoded in the operand field. This function specifies
526 the number of consecutive registers occupied by this operand. For
527 non-register operands, the return value is undefined. Returns
528 XTENSA_UNDEFINED on error. */
530 extern int
531 xtensa_operand_num_regs (xtensa_isa isa, xtensa_opcode opc, int opnd);
534 /* Some register operands do not completely identify the register being
535 accessed. For example, the operand value may be added to an internal
536 state value. By definition, this implies that the corresponding
537 regfile is not allocatable. Unknown registers should generally be
538 treated with worst-case assumptions. The function returns 0 if the
539 register value is unknown, 1 if known, and XTENSA_UNDEFINED on
540 error. */
542 extern int
543 xtensa_operand_is_known_reg (xtensa_isa isa, xtensa_opcode opc, int opnd);
546 /* Check if an immediate operand is PC-relative. Returns 0 for register
547 operands and non-PC-relative immediates, 1 for PC-relative
548 immediates, and XTENSA_UNDEFINED on error. */
550 extern int
551 xtensa_operand_is_PCrelative (xtensa_isa isa, xtensa_opcode opc, int opnd);
554 /* For PC-relative offset operands, the interpretation of the offset may
555 vary between opcodes, e.g., is it relative to the current PC or that
556 of the next instruction? The following functions are defined to
557 perform PC-relative relocations and to undo them (as in the
558 disassembler). The "do_reloc" function takes the desired address
559 value and the PC of the current instruction and sets the value to the
560 corresponding PC-relative offset (which can then be encoded and
561 stored into the operand field). The "undo_reloc" function takes the
562 unencoded offset value and the current PC and sets the value to the
563 appropriate address. The return values are non-zero on error. Note
564 that these functions do not replace the encode/decode functions; the
565 operands must be encoded/decoded separately and the encode functions
566 are responsible for detecting invalid operand values. */
568 extern int
569 xtensa_operand_do_reloc (xtensa_isa isa, xtensa_opcode opc, int opnd,
570 uint32 *valp, uint32 pc);
572 extern int
573 xtensa_operand_undo_reloc (xtensa_isa isa, xtensa_opcode opc, int opnd,
574 uint32 *valp, uint32 pc);
578 /* State Operands. */
580 /* Get the state accessed by a state operand. Returns XTENSA_UNDEFINED
581 on error. */
583 extern xtensa_state
584 xtensa_stateOperand_state (xtensa_isa isa, xtensa_opcode opc, int stOp);
587 /* Check if a state operand is an input ('i'), output ('o'), or inout
588 ('m') operand. Returns 0 on error. */
590 extern char
591 xtensa_stateOperand_inout (xtensa_isa isa, xtensa_opcode opc, int stOp);
595 /* Interface Operands. */
597 /* Get the external interface accessed by an interface operand.
598 Returns XTENSA_UNDEFINED on error. */
600 extern xtensa_interface
601 xtensa_interfaceOperand_interface (xtensa_isa isa, xtensa_opcode opc,
602 int ifOp);
606 /* Register Files. */
608 /* Regfiles include both "real" regfiles and "views", where a view
609 allows a group of adjacent registers in a real "parent" regfile to be
610 viewed as a single register. A regfile view has all the same
611 properties as its parent except for its (long) name, bit width, number
612 of entries, and default ctype. You can use the parent function to
613 distinguish these two classes. */
615 /* Look up a regfile by either its name or its abbreviated "short name".
616 Returns XTENSA_UNDEFINED on error. The "lookup_shortname" function
617 ignores "view" regfiles since they always have the same shortname as
618 their parents. */
620 extern xtensa_regfile
621 xtensa_regfile_lookup (xtensa_isa isa, const char *name);
623 extern xtensa_regfile
624 xtensa_regfile_lookup_shortname (xtensa_isa isa, const char *shortname);
627 /* Get the name or abbreviated "short name" of a regfile.
628 Returns null on error. */
630 extern const char *
631 xtensa_regfile_name (xtensa_isa isa, xtensa_regfile rf);
633 extern const char *
634 xtensa_regfile_shortname (xtensa_isa isa, xtensa_regfile rf);
637 /* Get the parent regfile of a "view" regfile. If the regfile is not a
638 view, the result is the same as the input parameter. Returns
639 XTENSA_UNDEFINED on error. */
641 extern xtensa_regfile
642 xtensa_regfile_view_parent (xtensa_isa isa, xtensa_regfile rf);
645 /* Get the bit width of a regfile or regfile view.
646 Returns XTENSA_UNDEFINED on error. */
648 extern int
649 xtensa_regfile_num_bits (xtensa_isa isa, xtensa_regfile rf);
652 /* Get the number of regfile entries. Returns XTENSA_UNDEFINED on
653 error. */
655 extern int
656 xtensa_regfile_num_entries (xtensa_isa isa, xtensa_regfile rf);
660 /* Processor States. */
662 /* Look up a state by name. Returns XTENSA_UNDEFINED on error. */
664 extern xtensa_state
665 xtensa_state_lookup (xtensa_isa isa, const char *name);
668 /* Get the name for a processor state. Returns null on error. */
670 extern const char *
671 xtensa_state_name (xtensa_isa isa, xtensa_state st);
674 /* Get the bit width for a processor state.
675 Returns XTENSA_UNDEFINED on error. */
677 extern int
678 xtensa_state_num_bits (xtensa_isa isa, xtensa_state st);
681 /* Check if a state is exported from the processor core. Returns 0 if
682 the condition is false, 1 if the condition is true, and
683 XTENSA_UNDEFINED on error. */
685 extern int
686 xtensa_state_is_exported (xtensa_isa isa, xtensa_state st);
690 /* Sysregs ("special registers" and "user registers"). */
692 /* Look up a register by its number and whether it is a "user register"
693 or a "special register". Returns XTENSA_UNDEFINED if the sysreg does
694 not exist. */
696 extern xtensa_sysreg
697 xtensa_sysreg_lookup (xtensa_isa isa, int num, int is_user);
700 /* Check if there exists a sysreg with a given name.
701 If not, this function returns XTENSA_UNDEFINED. */
703 extern xtensa_sysreg
704 xtensa_sysreg_lookup_name (xtensa_isa isa, const char *name);
707 /* Get the name of a sysreg. Returns null on error. */
709 extern const char *
710 xtensa_sysreg_name (xtensa_isa isa, xtensa_sysreg sysreg);
713 /* Get the register number. Returns XTENSA_UNDEFINED on error. */
715 extern int
716 xtensa_sysreg_number (xtensa_isa isa, xtensa_sysreg sysreg);
719 /* Check if a sysreg is a "special register" or a "user register".
720 Returns 0 for special registers, 1 for user registers and
721 XTENSA_UNDEFINED on error. */
723 extern int
724 xtensa_sysreg_is_user (xtensa_isa isa, xtensa_sysreg sysreg);
728 /* Interfaces. */
730 /* Find an interface by name. The return value is XTENSA_UNDEFINED if
731 the specified interface is not found. */
733 extern xtensa_interface
734 xtensa_interface_lookup (xtensa_isa isa, const char *ifname);
737 /* Get the name of an interface. Returns null on error. */
739 extern const char *
740 xtensa_interface_name (xtensa_isa isa, xtensa_interface intf);
743 /* Get the bit width for an interface.
744 Returns XTENSA_UNDEFINED on error. */
746 extern int
747 xtensa_interface_num_bits (xtensa_isa isa, xtensa_interface intf);
750 /* Check if an interface is an input ('i') or output ('o') with respect
751 to the Xtensa processor core. Returns 0 on error. */
753 extern char
754 xtensa_interface_inout (xtensa_isa isa, xtensa_interface intf);
757 /* Check if accessing an interface has potential side effects.
758 Currently "data" interfaces have side effects and "control"
759 interfaces do not. Returns 1 if there are side effects, 0 if not,
760 and XTENSA_UNDEFINED on error. */
762 extern int
763 xtensa_interface_has_side_effect (xtensa_isa isa, xtensa_interface intf);
766 /* Some interfaces may be related such that accessing one interface
767 has side effects on a set of related interfaces. The interfaces
768 are partitioned into equivalence classes of related interfaces, and
769 each class is assigned a unique identifier number. This function
770 returns the class identifier for an interface, or XTENSA_UNDEFINED
771 on error. These identifiers can be compared to determine if two
772 interfaces are related; the specific values of the identifiers have
773 no particular meaning otherwise. */
775 extern int
776 xtensa_interface_class_id (xtensa_isa isa, xtensa_interface intf);
780 /* Functional Units. */
782 /* Find a functional unit by name. The return value is XTENSA_UNDEFINED if
783 the specified unit is not found. */
785 extern xtensa_funcUnit
786 xtensa_funcUnit_lookup (xtensa_isa isa, const char *fname);
789 /* Get the name of a functional unit. Returns null on error. */
791 extern const char *
792 xtensa_funcUnit_name (xtensa_isa isa, xtensa_funcUnit fun);
795 /* Functional units may be replicated. See how many instances of a
796 particular function unit exist. Returns XTENSA_UNDEFINED on error. */
798 extern int
799 xtensa_funcUnit_num_copies (xtensa_isa isa, xtensa_funcUnit fun);
802 #ifdef __cplusplus
804 #endif
805 #endif /* XTENSA_LIBISA_H */