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1 /* Interface definition for configurable Xtensa ISA support.
2 Copyright 2003, 2004, 2005, 2006, 2008, 2010 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 3 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,
19 USA. */
21 #ifndef XTENSA_LIBISA_H
22 #define XTENSA_LIBISA_H
24 #ifdef __cplusplus
25 extern "C" {
26 #endif
28 /* Version number: This is intended to help support code that works with
29 versions of this library from multiple Xtensa releases. */
31 #define XTENSA_ISA_VERSION 7000
33 #ifndef uint32
34 #define uint32 unsigned int
35 #endif
37 /* This file defines the interface to the Xtensa ISA library. This
38 library contains most of the ISA-specific information for a
39 particular Xtensa processor. For example, the set of valid
40 instructions, their opcode encodings and operand fields are all
41 included here.
43 This interface basically defines a number of abstract data types.
45 . an instruction buffer - for holding the raw instruction bits
46 . ISA info - information about the ISA as a whole
47 . instruction formats - instruction size and slot structure
48 . opcodes - information about individual instructions
49 . operands - information about register and immediate instruction operands
50 . stateOperands - information about processor state instruction operands
51 . interfaceOperands - information about interface instruction operands
52 . register files - register file information
53 . processor states - internal processor state information
54 . system registers - "special registers" and "user registers"
55 . interfaces - TIE interfaces that are external to the processor
56 . functional units - TIE shared functions
58 The interface defines a set of functions to access each data type.
59 With the exception of the instruction buffer, the internal
60 representations of the data structures are hidden. All accesses must
61 be made through the functions defined here. */
63 typedef struct xtensa_isa_opaque { int unused; } *xtensa_isa;
66 /* Most of the Xtensa ISA entities (e.g., opcodes, regfiles, etc.) are
67 represented here using sequential integers beginning with 0. The
68 specific values are only fixed for a particular instantiation of an
69 xtensa_isa structure, so these values should only be used
70 internally. */
72 typedef int xtensa_opcode;
73 typedef int xtensa_format;
74 typedef int xtensa_regfile;
75 typedef int xtensa_state;
76 typedef int xtensa_sysreg;
77 typedef int xtensa_interface;
78 typedef int xtensa_funcUnit;
81 /* Define a unique value for undefined items. */
83 #define XTENSA_UNDEFINED -1
86 /* Overview of using this interface to decode/encode instructions:
88 Each Xtensa instruction is associated with a particular instruction
89 format, where the format defines a fixed number of slots for
90 operations. The formats for the core Xtensa ISA have only one slot,
91 but FLIX instructions may have multiple slots. Within each slot,
92 there is a single opcode and some number of associated operands.
94 The encoding and decoding functions operate on instruction buffers,
95 not on the raw bytes of the instructions. The same instruction
96 buffer data structure is used for both entire instructions and
97 individual slots in those instructions -- the contents of a slot need
98 to be extracted from or inserted into the buffer for the instruction
99 as a whole.
101 Decoding an instruction involves first finding the format, which
102 identifies the number of slots, and then decoding each slot
103 separately. A slot is decoded by finding the opcode and then using
104 the opcode to determine how many operands there are. For example:
106 xtensa_insnbuf_from_chars
107 xtensa_format_decode
108 for each slot {
109 xtensa_format_get_slot
110 xtensa_opcode_decode
111 for each operand {
112 xtensa_operand_get_field
113 xtensa_operand_decode
117 Encoding an instruction is roughly the same procedure in reverse:
119 xtensa_format_encode
120 for each slot {
121 xtensa_opcode_encode
122 for each operand {
123 xtensa_operand_encode
124 xtensa_operand_set_field
126 xtensa_format_set_slot
128 xtensa_insnbuf_to_chars
132 /* Error handling. */
134 /* Error codes. The code for the most recent error condition can be
135 retrieved with the "errno" function. For any result other than
136 xtensa_isa_ok, an error message containing additional information
137 about the problem can be retrieved using the "error_msg" function.
138 The error messages are stored in an internal buffer, which should
139 not be freed and may be overwritten by subsequent operations. */
141 typedef enum xtensa_isa_status_enum
143 xtensa_isa_ok = 0,
144 xtensa_isa_bad_format,
145 xtensa_isa_bad_slot,
146 xtensa_isa_bad_opcode,
147 xtensa_isa_bad_operand,
148 xtensa_isa_bad_field,
149 xtensa_isa_bad_iclass,
150 xtensa_isa_bad_regfile,
151 xtensa_isa_bad_sysreg,
152 xtensa_isa_bad_state,
153 xtensa_isa_bad_interface,
154 xtensa_isa_bad_funcUnit,
155 xtensa_isa_wrong_slot,
156 xtensa_isa_no_field,
157 xtensa_isa_out_of_memory,
158 xtensa_isa_buffer_overflow,
159 xtensa_isa_internal_error,
160 xtensa_isa_bad_value
161 } xtensa_isa_status;
163 extern xtensa_isa_status
164 xtensa_isa_errno (xtensa_isa isa);
166 extern char *
167 xtensa_isa_error_msg (xtensa_isa isa);
171 /* Instruction buffers. */
173 typedef uint32 xtensa_insnbuf_word;
174 typedef xtensa_insnbuf_word *xtensa_insnbuf;
177 /* Get the size in "insnbuf_words" of the xtensa_insnbuf array. */
179 extern int
180 xtensa_insnbuf_size (xtensa_isa isa);
183 /* Allocate an xtensa_insnbuf of the right size. */
185 extern xtensa_insnbuf
186 xtensa_insnbuf_alloc (xtensa_isa isa);
189 /* Release an xtensa_insnbuf. */
191 extern void
192 xtensa_insnbuf_free (xtensa_isa isa, xtensa_insnbuf buf);
195 /* Conversion between raw memory (char arrays) and our internal
196 instruction representation. This is complicated by the Xtensa ISA's
197 variable instruction lengths. When converting to chars, the buffer
198 must contain a valid instruction so we know how many bytes to copy;
199 thus, the "to_chars" function returns the number of bytes copied or
200 XTENSA_UNDEFINED on error. The "from_chars" function first reads the
201 minimal number of bytes required to decode the instruction length and
202 then proceeds to copy the entire instruction into the buffer; if the
203 memory does not contain a valid instruction, it copies the maximum
204 number of bytes required for the longest Xtensa instruction. The
205 "num_chars" argument may be used to limit the number of bytes that
206 can be read or written. Otherwise, if "num_chars" is zero, the
207 functions may read or write past the end of the code. */
209 extern int
210 xtensa_insnbuf_to_chars (xtensa_isa isa, const xtensa_insnbuf insn,
211 unsigned char *cp, int num_chars);
213 extern void
214 xtensa_insnbuf_from_chars (xtensa_isa isa, xtensa_insnbuf insn,
215 const unsigned char *cp, int num_chars);
219 /* ISA information. */
221 /* Initialize the ISA information. */
223 extern xtensa_isa
224 xtensa_isa_init (xtensa_isa_status *errno_p, char **error_msg_p);
227 /* Deallocate an xtensa_isa structure. */
229 extern void
230 xtensa_isa_free (xtensa_isa isa);
233 /* Get the maximum instruction size in bytes. */
235 extern int
236 xtensa_isa_maxlength (xtensa_isa isa);
239 /* Decode the length in bytes of an instruction in raw memory (not an
240 insnbuf). This function reads only the minimal number of bytes
241 required to decode the instruction length. Returns
242 XTENSA_UNDEFINED on error. */
244 extern int
245 xtensa_isa_length_from_chars (xtensa_isa isa, const unsigned char *cp);
248 /* Get the number of stages in the processor's pipeline. The pipeline
249 stage values returned by other functions in this library will range
250 from 0 to N-1, where N is the value returned by this function.
251 Note that the stage numbers used here may not correspond to the
252 actual processor hardware, e.g., the hardware may have additional
253 stages before stage 0. Returns XTENSA_UNDEFINED on error. */
255 extern int
256 xtensa_isa_num_pipe_stages (xtensa_isa isa);
259 /* Get the number of various entities that are defined for this processor. */
261 extern int
262 xtensa_isa_num_formats (xtensa_isa isa);
264 extern int
265 xtensa_isa_num_opcodes (xtensa_isa isa);
267 extern int
268 xtensa_isa_num_regfiles (xtensa_isa isa);
270 extern int
271 xtensa_isa_num_states (xtensa_isa isa);
273 extern int
274 xtensa_isa_num_sysregs (xtensa_isa isa);
276 extern int
277 xtensa_isa_num_interfaces (xtensa_isa isa);
279 extern int
280 xtensa_isa_num_funcUnits (xtensa_isa isa);
284 /* Instruction formats. */
286 /* Get the name of a format. Returns null on error. */
288 extern const char *
289 xtensa_format_name (xtensa_isa isa, xtensa_format fmt);
292 /* Given a format name, return the format number. Returns
293 XTENSA_UNDEFINED if the name is not a valid format. */
295 extern xtensa_format
296 xtensa_format_lookup (xtensa_isa isa, const char *fmtname);
299 /* Decode the instruction format from a binary instruction buffer.
300 Returns XTENSA_UNDEFINED if the format is not recognized. */
302 extern xtensa_format
303 xtensa_format_decode (xtensa_isa isa, const xtensa_insnbuf insn);
306 /* Set the instruction format field(s) in a binary instruction buffer.
307 All the other fields are set to zero. Returns non-zero on error. */
309 extern int
310 xtensa_format_encode (xtensa_isa isa, xtensa_format fmt, xtensa_insnbuf insn);
313 /* Find the length (in bytes) of an instruction. Returns
314 XTENSA_UNDEFINED on error. */
316 extern int
317 xtensa_format_length (xtensa_isa isa, xtensa_format fmt);
320 /* Get the number of slots in an instruction. Returns XTENSA_UNDEFINED
321 on error. */
323 extern int
324 xtensa_format_num_slots (xtensa_isa isa, xtensa_format fmt);
327 /* Get the opcode for a no-op in a particular slot.
328 Returns XTENSA_UNDEFINED on error. */
330 extern xtensa_opcode
331 xtensa_format_slot_nop_opcode (xtensa_isa isa, xtensa_format fmt, int slot);
334 /* Get the bits for a specified slot out of an insnbuf for the
335 instruction as a whole and put them into an insnbuf for that one
336 slot, and do the opposite to set a slot. Return non-zero on error. */
338 extern int
339 xtensa_format_get_slot (xtensa_isa isa, xtensa_format fmt, int slot,
340 const xtensa_insnbuf insn, xtensa_insnbuf slotbuf);
342 extern int
343 xtensa_format_set_slot (xtensa_isa isa, xtensa_format fmt, int slot,
344 xtensa_insnbuf insn, const xtensa_insnbuf slotbuf);
348 /* Opcode information. */
350 /* Translate a mnemonic name to an opcode. Returns XTENSA_UNDEFINED if
351 the name is not a valid opcode mnemonic. */
353 extern xtensa_opcode
354 xtensa_opcode_lookup (xtensa_isa isa, const char *opname);
357 /* Decode the opcode for one instruction slot from a binary instruction
358 buffer. Returns the opcode or XTENSA_UNDEFINED if the opcode is
359 illegal. */
361 extern xtensa_opcode
362 xtensa_opcode_decode (xtensa_isa isa, xtensa_format fmt, int slot,
363 const xtensa_insnbuf slotbuf);
366 /* Set the opcode field(s) for an instruction slot. All other fields
367 in the slot are set to zero. Returns non-zero if the opcode cannot
368 be encoded. */
370 extern int
371 xtensa_opcode_encode (xtensa_isa isa, xtensa_format fmt, int slot,
372 xtensa_insnbuf slotbuf, xtensa_opcode opc);
375 /* Get the mnemonic name for an opcode. Returns null on error. */
377 extern const char *
378 xtensa_opcode_name (xtensa_isa isa, xtensa_opcode opc);
381 /* Check various properties of opcodes. These functions return 0 if
382 the condition is false, 1 if the condition is true, and
383 XTENSA_UNDEFINED on error. The instructions are classified as
384 follows:
386 branch: conditional branch; may fall through to next instruction (B*)
387 jump: unconditional branch (J, JX, RET*, RF*)
388 loop: zero-overhead loop (LOOP*)
389 call: unconditional call; control returns to next instruction (CALL*)
391 For the opcodes that affect control flow in some way, the branch
392 target may be specified by an immediate operand or it may be an
393 address stored in a register. You can distinguish these by
394 checking if the instruction has a PC-relative immediate
395 operand. */
397 extern int
398 xtensa_opcode_is_branch (xtensa_isa isa, xtensa_opcode opc);
400 extern int
401 xtensa_opcode_is_jump (xtensa_isa isa, xtensa_opcode opc);
403 extern int
404 xtensa_opcode_is_loop (xtensa_isa isa, xtensa_opcode opc);
406 extern int
407 xtensa_opcode_is_call (xtensa_isa isa, xtensa_opcode opc);
410 /* Find the number of ordinary operands, state operands, and interface
411 operands for an instruction. These return XTENSA_UNDEFINED on
412 error. */
414 extern int
415 xtensa_opcode_num_operands (xtensa_isa isa, xtensa_opcode opc);
417 extern int
418 xtensa_opcode_num_stateOperands (xtensa_isa isa, xtensa_opcode opc);
420 extern int
421 xtensa_opcode_num_interfaceOperands (xtensa_isa isa, xtensa_opcode opc);
424 /* Get functional unit usage requirements for an opcode. Each "use"
425 is identified by a <functional unit, pipeline stage> pair. The
426 "num_funcUnit_uses" function returns the number of these "uses" or
427 XTENSA_UNDEFINED on error. The "funcUnit_use" function returns
428 a pointer to a "use" pair or null on error. */
430 typedef struct xtensa_funcUnit_use_struct
432 xtensa_funcUnit unit;
433 int stage;
434 } xtensa_funcUnit_use;
436 extern int
437 xtensa_opcode_num_funcUnit_uses (xtensa_isa isa, xtensa_opcode opc);
439 extern xtensa_funcUnit_use *
440 xtensa_opcode_funcUnit_use (xtensa_isa isa, xtensa_opcode opc, int u);
444 /* Operand information. */
446 /* Get the name of an operand. Returns null on error. */
448 extern const char *
449 xtensa_operand_name (xtensa_isa isa, xtensa_opcode opc, int opnd);
452 /* Some operands are "invisible", i.e., not explicitly specified in
453 assembly language. When assembling an instruction, you need not set
454 the values of invisible operands, since they are either hardwired or
455 derived from other field values. The values of invisible operands
456 can be examined in the same way as other operands, but remember that
457 an invisible operand may get its value from another visible one, so
458 the entire instruction must be available before examining the
459 invisible operand values. This function returns 1 if an operand is
460 visible, 0 if it is invisible, or XTENSA_UNDEFINED on error. Note
461 that whether an operand is visible is orthogonal to whether it is
462 "implicit", i.e., whether it is encoded in a field in the
463 instruction. */
465 extern int
466 xtensa_operand_is_visible (xtensa_isa isa, xtensa_opcode opc, int opnd);
469 /* Check if an operand is an input ('i'), output ('o'), or inout ('m')
470 operand. Note: The output operand of a conditional assignment
471 (e.g., movnez) appears here as an inout ('m') even if it is declared
472 in the TIE code as an output ('o'); this allows the compiler to
473 properly handle register allocation for conditional assignments.
474 Returns 0 on error. */
476 extern char
477 xtensa_operand_inout (xtensa_isa isa, xtensa_opcode opc, int opnd);
480 /* Get and set the raw (encoded) value of the field for the specified
481 operand. The "set" function does not check if the value fits in the
482 field; that is done by the "encode" function below. Both of these
483 functions return non-zero on error, e.g., if the field is not defined
484 for the specified slot. */
486 extern int
487 xtensa_operand_get_field (xtensa_isa isa, xtensa_opcode opc, int opnd,
488 xtensa_format fmt, int slot,
489 const xtensa_insnbuf slotbuf, uint32 *valp);
491 extern int
492 xtensa_operand_set_field (xtensa_isa isa, xtensa_opcode opc, int opnd,
493 xtensa_format fmt, int slot,
494 xtensa_insnbuf slotbuf, uint32 val);
497 /* Encode and decode operands. The raw bits in the operand field may
498 be encoded in a variety of different ways. These functions hide
499 the details of that encoding. The result values are returned through
500 the argument pointer. The return value is non-zero on error. */
502 extern int
503 xtensa_operand_encode (xtensa_isa isa, xtensa_opcode opc, int opnd,
504 uint32 *valp);
506 extern int
507 xtensa_operand_decode (xtensa_isa isa, xtensa_opcode opc, int opnd,
508 uint32 *valp);
511 /* An operand may be either a register operand or an immediate of some
512 sort (e.g., PC-relative or not). The "is_register" function returns
513 0 if the operand is an immediate, 1 if it is a register, and
514 XTENSA_UNDEFINED on error. The "regfile" function returns the
515 regfile for a register operand, or XTENSA_UNDEFINED on error. */
517 extern int
518 xtensa_operand_is_register (xtensa_isa isa, xtensa_opcode opc, int opnd);
520 extern xtensa_regfile
521 xtensa_operand_regfile (xtensa_isa isa, xtensa_opcode opc, int opnd);
524 /* Register operands may span multiple consecutive registers, e.g., a
525 64-bit data type may occupy two 32-bit registers. Only the first
526 register is encoded in the operand field. This function specifies
527 the number of consecutive registers occupied by this operand. For
528 non-register operands, the return value is undefined. Returns
529 XTENSA_UNDEFINED on error. */
531 extern int
532 xtensa_operand_num_regs (xtensa_isa isa, xtensa_opcode opc, int opnd);
535 /* Some register operands do not completely identify the register being
536 accessed. For example, the operand value may be added to an internal
537 state value. By definition, this implies that the corresponding
538 regfile is not allocatable. Unknown registers should generally be
539 treated with worst-case assumptions. The function returns 0 if the
540 register value is unknown, 1 if known, and XTENSA_UNDEFINED on
541 error. */
543 extern int
544 xtensa_operand_is_known_reg (xtensa_isa isa, xtensa_opcode opc, int opnd);
547 /* Check if an immediate operand is PC-relative. Returns 0 for register
548 operands and non-PC-relative immediates, 1 for PC-relative
549 immediates, and XTENSA_UNDEFINED on error. */
551 extern int
552 xtensa_operand_is_PCrelative (xtensa_isa isa, xtensa_opcode opc, int opnd);
555 /* For PC-relative offset operands, the interpretation of the offset may
556 vary between opcodes, e.g., is it relative to the current PC or that
557 of the next instruction? The following functions are defined to
558 perform PC-relative relocations and to undo them (as in the
559 disassembler). The "do_reloc" function takes the desired address
560 value and the PC of the current instruction and sets the value to the
561 corresponding PC-relative offset (which can then be encoded and
562 stored into the operand field). The "undo_reloc" function takes the
563 unencoded offset value and the current PC and sets the value to the
564 appropriate address. The return values are non-zero on error. Note
565 that these functions do not replace the encode/decode functions; the
566 operands must be encoded/decoded separately and the encode functions
567 are responsible for detecting invalid operand values. */
569 extern int
570 xtensa_operand_do_reloc (xtensa_isa isa, xtensa_opcode opc, int opnd,
571 uint32 *valp, uint32 pc);
573 extern int
574 xtensa_operand_undo_reloc (xtensa_isa isa, xtensa_opcode opc, int opnd,
575 uint32 *valp, uint32 pc);
579 /* State Operands. */
581 /* Get the state accessed by a state operand. Returns XTENSA_UNDEFINED
582 on error. */
584 extern xtensa_state
585 xtensa_stateOperand_state (xtensa_isa isa, xtensa_opcode opc, int stOp);
588 /* Check if a state operand is an input ('i'), output ('o'), or inout
589 ('m') operand. Returns 0 on error. */
591 extern char
592 xtensa_stateOperand_inout (xtensa_isa isa, xtensa_opcode opc, int stOp);
596 /* Interface Operands. */
598 /* Get the external interface accessed by an interface operand.
599 Returns XTENSA_UNDEFINED on error. */
601 extern xtensa_interface
602 xtensa_interfaceOperand_interface (xtensa_isa isa, xtensa_opcode opc,
603 int ifOp);
607 /* Register Files. */
609 /* Regfiles include both "real" regfiles and "views", where a view
610 allows a group of adjacent registers in a real "parent" regfile to be
611 viewed as a single register. A regfile view has all the same
612 properties as its parent except for its (long) name, bit width, number
613 of entries, and default ctype. You can use the parent function to
614 distinguish these two classes. */
616 /* Look up a regfile by either its name or its abbreviated "short name".
617 Returns XTENSA_UNDEFINED on error. The "lookup_shortname" function
618 ignores "view" regfiles since they always have the same shortname as
619 their parents. */
621 extern xtensa_regfile
622 xtensa_regfile_lookup (xtensa_isa isa, const char *name);
624 extern xtensa_regfile
625 xtensa_regfile_lookup_shortname (xtensa_isa isa, const char *shortname);
628 /* Get the name or abbreviated "short name" of a regfile.
629 Returns null on error. */
631 extern const char *
632 xtensa_regfile_name (xtensa_isa isa, xtensa_regfile rf);
634 extern const char *
635 xtensa_regfile_shortname (xtensa_isa isa, xtensa_regfile rf);
638 /* Get the parent regfile of a "view" regfile. If the regfile is not a
639 view, the result is the same as the input parameter. Returns
640 XTENSA_UNDEFINED on error. */
642 extern xtensa_regfile
643 xtensa_regfile_view_parent (xtensa_isa isa, xtensa_regfile rf);
646 /* Get the bit width of a regfile or regfile view.
647 Returns XTENSA_UNDEFINED on error. */
649 extern int
650 xtensa_regfile_num_bits (xtensa_isa isa, xtensa_regfile rf);
653 /* Get the number of regfile entries. Returns XTENSA_UNDEFINED on
654 error. */
656 extern int
657 xtensa_regfile_num_entries (xtensa_isa isa, xtensa_regfile rf);
661 /* Processor States. */
663 /* Look up a state by name. Returns XTENSA_UNDEFINED on error. */
665 extern xtensa_state
666 xtensa_state_lookup (xtensa_isa isa, const char *name);
669 /* Get the name for a processor state. Returns null on error. */
671 extern const char *
672 xtensa_state_name (xtensa_isa isa, xtensa_state st);
675 /* Get the bit width for a processor state.
676 Returns XTENSA_UNDEFINED on error. */
678 extern int
679 xtensa_state_num_bits (xtensa_isa isa, xtensa_state st);
682 /* Check if a state is exported from the processor core. Returns 0 if
683 the condition is false, 1 if the condition is true, and
684 XTENSA_UNDEFINED on error. */
686 extern int
687 xtensa_state_is_exported (xtensa_isa isa, xtensa_state st);
690 /* Check for a "shared_or" state. Returns 0 if the condition is false,
691 1 if the condition is true, and XTENSA_UNDEFINED on error. */
693 extern int
694 xtensa_state_is_shared_or (xtensa_isa isa, xtensa_state st);
698 /* Sysregs ("special registers" and "user registers"). */
700 /* Look up a register by its number and whether it is a "user register"
701 or a "special register". Returns XTENSA_UNDEFINED if the sysreg does
702 not exist. */
704 extern xtensa_sysreg
705 xtensa_sysreg_lookup (xtensa_isa isa, int num, int is_user);
708 /* Check if there exists a sysreg with a given name.
709 If not, this function returns XTENSA_UNDEFINED. */
711 extern xtensa_sysreg
712 xtensa_sysreg_lookup_name (xtensa_isa isa, const char *name);
715 /* Get the name of a sysreg. Returns null on error. */
717 extern const char *
718 xtensa_sysreg_name (xtensa_isa isa, xtensa_sysreg sysreg);
721 /* Get the register number. Returns XTENSA_UNDEFINED on error. */
723 extern int
724 xtensa_sysreg_number (xtensa_isa isa, xtensa_sysreg sysreg);
727 /* Check if a sysreg is a "special register" or a "user register".
728 Returns 0 for special registers, 1 for user registers and
729 XTENSA_UNDEFINED on error. */
731 extern int
732 xtensa_sysreg_is_user (xtensa_isa isa, xtensa_sysreg sysreg);
736 /* Interfaces. */
738 /* Find an interface by name. The return value is XTENSA_UNDEFINED if
739 the specified interface is not found. */
741 extern xtensa_interface
742 xtensa_interface_lookup (xtensa_isa isa, const char *ifname);
745 /* Get the name of an interface. Returns null on error. */
747 extern const char *
748 xtensa_interface_name (xtensa_isa isa, xtensa_interface intf);
751 /* Get the bit width for an interface.
752 Returns XTENSA_UNDEFINED on error. */
754 extern int
755 xtensa_interface_num_bits (xtensa_isa isa, xtensa_interface intf);
758 /* Check if an interface is an input ('i') or output ('o') with respect
759 to the Xtensa processor core. Returns 0 on error. */
761 extern char
762 xtensa_interface_inout (xtensa_isa isa, xtensa_interface intf);
765 /* Check if accessing an interface has potential side effects.
766 Currently "data" interfaces have side effects and "control"
767 interfaces do not. Returns 1 if there are side effects, 0 if not,
768 and XTENSA_UNDEFINED on error. */
770 extern int
771 xtensa_interface_has_side_effect (xtensa_isa isa, xtensa_interface intf);
774 /* Some interfaces may be related such that accessing one interface
775 has side effects on a set of related interfaces. The interfaces
776 are partitioned into equivalence classes of related interfaces, and
777 each class is assigned a unique identifier number. This function
778 returns the class identifier for an interface, or XTENSA_UNDEFINED
779 on error. These identifiers can be compared to determine if two
780 interfaces are related; the specific values of the identifiers have
781 no particular meaning otherwise. */
783 extern int
784 xtensa_interface_class_id (xtensa_isa isa, xtensa_interface intf);
788 /* Functional Units. */
790 /* Find a functional unit by name. The return value is XTENSA_UNDEFINED if
791 the specified unit is not found. */
793 extern xtensa_funcUnit
794 xtensa_funcUnit_lookup (xtensa_isa isa, const char *fname);
797 /* Get the name of a functional unit. Returns null on error. */
799 extern const char *
800 xtensa_funcUnit_name (xtensa_isa isa, xtensa_funcUnit fun);
803 /* Functional units may be replicated. See how many instances of a
804 particular function unit exist. Returns XTENSA_UNDEFINED on error. */
806 extern int
807 xtensa_funcUnit_num_copies (xtensa_isa isa, xtensa_funcUnit fun);
810 #ifdef __cplusplus
812 #endif
813 #endif /* XTENSA_LIBISA_H */