| /* Interface definition for configurable Xtensa ISA support. |
| Copyright 2003 Free Software Foundation, Inc. |
| |
| This file is part of BFD, the Binary File Descriptor library. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program; if not, write to the Free Software |
| Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| |
| #ifndef XTENSA_LIBISA_H |
| #define XTENSA_LIBISA_H |
| |
| /* Use the statically-linked version for the GNU tools. */ |
| #define STATIC_LIBISA 1 |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| #ifndef uint32 |
| #define uint32 unsigned int |
| #endif |
| |
| /* This file defines the interface to the Xtensa ISA library. This library |
| contains most of the ISA-specific information for a particular Xtensa |
| processor. For example, the set of valid instructions, their opcode |
| encodings and operand fields are all included here. To support Xtensa's |
| configurability and user-defined instruction extensions (i.e., TIE), the |
| library is initialized by loading one or more dynamic libraries; only a |
| small set of interface code is present in the statically-linked portion |
| of the library. |
| |
| This interface basically defines four abstract data types. |
| |
| . an instruction buffer - for holding the raw instruction bits |
| . ISA info - information about the ISA as a whole |
| . opcode info - information about individual instructions |
| . operand info - information about specific instruction operands |
| |
| It would be nice to implement these as classes in C++, but the library is |
| implemented in C to match the expectations of the GNU tools. |
| Instead, the interface defines a set of functions to access each data |
| type. With the exception of the instruction buffer, the internal |
| representations of the data structures are hidden. All accesses must be |
| made through the functions defined here. */ |
| |
| typedef void* xtensa_isa; |
| typedef void* xtensa_operand; |
| |
| |
| /* Opcodes are represented here using sequential integers beginning with 0. |
| The specific value used for a particular opcode is only fixed for a |
| particular instantiation of an xtensa_isa structure, so these values |
| should only be used internally. */ |
| typedef int xtensa_opcode; |
| |
| /* Define a unique value for undefined opcodes ("static const int" doesn't |
| seem to work for this because EGCS 1.0.3 on i686-Linux without -O won't |
| allow it to be used as an initializer). */ |
| #define XTENSA_UNDEFINED -1 |
| |
| |
| typedef int libisa_module_specifier; |
| |
| extern xtensa_isa xtensa_isa_init (void); |
| |
| |
| /* Instruction buffers. */ |
| |
| typedef uint32 xtensa_insnbuf_word; |
| typedef xtensa_insnbuf_word *xtensa_insnbuf; |
| |
| /* Get the size in words of the xtensa_insnbuf array. */ |
| extern int xtensa_insnbuf_size (xtensa_isa); |
| |
| /* Allocate (with malloc) an xtensa_insnbuf of the right size. */ |
| extern xtensa_insnbuf xtensa_insnbuf_alloc (xtensa_isa); |
| |
| /* Release (with free) an xtensa_insnbuf of the right size. */ |
| extern void xtensa_insnbuf_free (xtensa_insnbuf); |
| |
| /* Inward and outward conversion from memory images (byte streams) to our |
| internal instruction representation. */ |
| extern void xtensa_insnbuf_to_chars (xtensa_isa, const xtensa_insnbuf, |
| char *); |
| |
| extern void xtensa_insnbuf_from_chars (xtensa_isa, xtensa_insnbuf, |
| const char *); |
| |
| |
| /* ISA information. */ |
| |
| /* Load the ISA information from a shared library. If successful, this returns |
| a value which identifies the ISA for use in subsequent calls to the ISA |
| library; otherwise, it returns NULL. Multiple ISAs can be loaded to support |
| heterogeneous multiprocessor systems. */ |
| extern xtensa_isa xtensa_load_isa (libisa_module_specifier); |
| |
| /* Extend an existing set of ISA information by loading an additional shared |
| library of ISA information. This is primarily intended for loading TIE |
| extensions. If successful, the return value is non-zero. */ |
| extern int xtensa_extend_isa (xtensa_isa, libisa_module_specifier); |
| |
| /* The default ISA. This variable is set automatically to the ISA most |
| recently loaded and is provided as a convenience. An exception is the GNU |
| opcodes library, where there is a fixed interface that does not allow |
| passing the ISA as a parameter and the ISA must be taken from this global |
| variable. (Note: Since this variable is just a convenience, it is not |
| exported when libisa is built as a DLL, due to the hassle of dealing with |
| declspecs.) */ |
| extern xtensa_isa xtensa_default_isa; |
| |
| |
| /* Deallocate an xtensa_isa structure. */ |
| extern void xtensa_isa_free (xtensa_isa); |
| |
| /* Get the maximum instruction size in bytes. */ |
| extern int xtensa_insn_maxlength (xtensa_isa); |
| |
| /* Get the total number of opcodes for this processor. */ |
| extern int xtensa_num_opcodes (xtensa_isa); |
| |
| /* Translate a mnemonic name to an opcode. Returns XTENSA_UNDEFINED if |
| the name is not a valid opcode mnemonic. */ |
| extern xtensa_opcode xtensa_opcode_lookup (xtensa_isa, const char *); |
| |
| /* Decode a binary instruction buffer. Returns the opcode or |
| XTENSA_UNDEFINED if the instruction is illegal. */ |
| extern xtensa_opcode xtensa_decode_insn (xtensa_isa, const xtensa_insnbuf); |
| |
| |
| /* Opcode information. */ |
| |
| /* Set the opcode field(s) in a binary instruction buffer. The operand |
| fields are set to zero. */ |
| extern void xtensa_encode_insn (xtensa_isa, xtensa_opcode, xtensa_insnbuf); |
| |
| /* Get the mnemonic name for an opcode. */ |
| extern const char * xtensa_opcode_name (xtensa_isa, xtensa_opcode); |
| |
| /* Find the length (in bytes) of an instruction. */ |
| extern int xtensa_insn_length (xtensa_isa, xtensa_opcode); |
| |
| /* Find the length of an instruction by looking only at the first byte. */ |
| extern int xtensa_insn_length_from_first_byte (xtensa_isa, char); |
| |
| /* Find the number of operands for an instruction. */ |
| extern int xtensa_num_operands (xtensa_isa, xtensa_opcode); |
| |
| /* Get the information about operand number "opnd" of a particular opcode. */ |
| extern xtensa_operand xtensa_get_operand (xtensa_isa, xtensa_opcode, int); |
| |
| /* Operand information. */ |
| |
| /* Find the kind of operand. There are three possibilities: |
| 1) PC-relative immediates (e.g., "l", "L"). These can be identified with |
| the xtensa_operand_isPCRelative function. |
| 2) non-PC-relative immediates ("i"). |
| 3) register-file short names (e.g., "a", "b", "m" and others defined |
| via TIE). */ |
| extern char * xtensa_operand_kind (xtensa_operand); |
| |
| /* Check if an operand is an input ('<'), output ('>'), or inout ('=') |
| operand. Note: The output operand of a conditional assignment |
| (e.g., movnez) appears here as an inout ('=') even if it is declared |
| in the TIE code as an output ('>'); this allows the compiler to |
| properly handle register allocation for conditional assignments. */ |
| extern char xtensa_operand_inout (xtensa_operand); |
| |
| /* Get and set the raw (encoded) value of the field for the specified |
| operand. The "set" function does not check if the value fits in the |
| field; that is done by the "encode" function below. */ |
| extern uint32 xtensa_operand_get_field (xtensa_operand, const xtensa_insnbuf); |
| |
| extern void xtensa_operand_set_field (xtensa_operand, xtensa_insnbuf, uint32); |
| |
| |
| /* Encode and decode operands. The raw bits in the operand field |
| may be encoded in a variety of different ways. These functions hide the |
| details of that encoding. The encode function has a special return type |
| (xtensa_encode_result) to indicate success or the reason for failure; the |
| encoded value is returned through the argument pointer. The decode function |
| has no possibility of failure and returns the decoded value. */ |
| |
| typedef enum |
| { |
| xtensa_encode_result_ok, |
| xtensa_encode_result_align, |
| xtensa_encode_result_not_in_table, |
| xtensa_encode_result_too_low, |
| xtensa_encode_result_too_high, |
| xtensa_encode_result_not_ok, |
| xtensa_encode_result_max = xtensa_encode_result_not_ok |
| } xtensa_encode_result; |
| |
| extern xtensa_encode_result xtensa_operand_encode (xtensa_operand, uint32 *); |
| |
| extern uint32 xtensa_operand_decode (xtensa_operand, uint32); |
| |
| |
| /* For PC-relative offset operands, the interpretation of the offset may vary |
| between opcodes, e.g., is it relative to the current PC or that of the next |
| instruction? The following functions are defined to perform PC-relative |
| relocations and to undo them (as in the disassembler). The first function |
| takes the desired address and the PC of the current instruction and returns |
| the unencoded value to be stored in the offset field. The second function |
| takes the unencoded offset value and the current PC and returns the address. |
| Note that these functions do not replace the encode/decode functions; the |
| operands must be encoded/decoded separately. */ |
| |
| extern int xtensa_operand_isPCRelative (xtensa_operand); |
| |
| extern uint32 xtensa_operand_do_reloc (xtensa_operand, uint32, uint32); |
| |
| extern uint32 xtensa_operand_undo_reloc (xtensa_operand, uint32, uint32); |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| #endif /* XTENSA_LIBISA_H */ |