From aa2289c2a3faf0f198e47943dcb29e0c16223be8 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Mon, 3 May 1999 07:29:11 +0000 Subject: Initial revision --- gas/itbl-parse.y | 459 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 459 insertions(+) create mode 100644 gas/itbl-parse.y (limited to 'gas/itbl-parse.y') diff --git a/gas/itbl-parse.y b/gas/itbl-parse.y new file mode 100644 index 0000000000..7966ee8fe1 --- /dev/null +++ b/gas/itbl-parse.y @@ -0,0 +1,459 @@ +/* itbl-parse.y + Copyright (C) 1997 Free Software Foundation, Inc. + + This file is part of GAS, the GNU Assembler. + + GAS 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, or (at your option) + any later version. + + GAS 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 GAS; see the file COPYING. If not, write to the Free + Software Foundation, 59 Temple Place - Suite 330, Boston, MA + 02111-1307, USA. */ + +%{ + +/* + +Yacc grammar for instruction table entries. + +======================================================================= +Original Instruction table specification document: + + MIPS Coprocessor Table Specification + ==================================== + +This document describes the format of the MIPS coprocessor table. The +table specifies a list of valid functions, data registers and control +registers that can be used in coprocessor instructions. This list, +together with the coprocessor instruction classes listed below, +specifies the complete list of coprocessor instructions that will +be recognized and assembled by the GNU assembler. In effect, +this makes the GNU assembler table-driven, where the table is +specified by the programmer. + +The table is an ordinary text file that the GNU assembler reads when +it starts. Using the information in the table, the assembler +generates an internal list of valid coprocessor registers and +functions. The assembler uses this internal list in addition to the +standard MIPS registers and instructions which are built-in to the +assembler during code generation. + +To specify the coprocessor table when invoking the GNU assembler, use +the command line option "--itbl file", where file is the +complete name of the table, including path and extension. + +Examples: + + gas -t cop.tbl test.s -o test.o + gas -t /usr/local/lib/cop.tbl test.s -o test.o + gas --itbl d:\gnu\data\cop.tbl test.s -o test.o + +Only one table may be supplied during a single invocation of +the assembler. + + +Instruction classes +=================== + +Below is a list of the valid coprocessor instruction classes for +any given coprocessor "z". These instructions are already recognized +by the assembler, and are listed here only for reference. + +Class format instructions +------------------------------------------------- +Class1: + op base rt offset + LWCz rt,offset (base) + SWCz rt,offset (base) +Class2: + COPz sub rt rd 0 + MTCz rt,rd + MFCz rt,rd + CTCz rt,rd + CFCz rt,rd +Class3: + COPz CO cofun + COPz cofun +Class4: + COPz BC br offset + BCzT offset + BCzF offset +Class5: + COPz sub rt rd 0 + DMFCz rt,rd + DMTCz rt,rd +Class6: + op base rt offset + LDCz rt,offset (base) + SDCz rt,offset (base) +Class7: + COPz BC br offset + BCzTL offset + BCzFL offset + +The coprocessor table defines coprocessor-specific registers that can +be used with all of the above classes of instructions, where +appropriate. It also defines additional coprocessor-specific +functions for Class3 (COPz cofun) instructions, Thus, the table allows +the programmer to use convenient mnemonics and operands for these +functions, instead of the COPz mmenmonic and cofun operand. + +The names of the MIPS general registers and their aliases are defined +by the assembler and will be recognized as valid register names by the +assembler when used (where allowed) in coprocessor instructions. +However, the names and values of all coprocessor data and control +register mnemonics must be specified in the coprocessor table. + + +Table Grammar +============= + +Here is the grammar for the coprocessor table: + + table -> entry* + + entry -> [z entrydef] [comment] '\n' + + entrydef -> type name val + entrydef -> 'insn' name val funcdef ; type of entry (instruction) + + z -> 'p'['0'..'3'] ; processor number + type -> ['dreg' | 'creg' | 'greg' ] ; type of entry (register) + ; 'dreg', 'creg' or 'greg' specifies a data, control, or general + ; register mnemonic, respectively + name -> [ltr|dec]* ; mnemonic of register/function + val -> [dec|hex] ; register/function number (integer constant) + + funcdef -> frange flags fields + ; bitfield range for opcode + ; list of fields' formats + fields -> field* + field -> [','] ftype frange flags + flags -> ['*' flagexpr] + flagexpr -> '[' flagexpr ']' + flagexpr -> val '|' flagexpr + ftype -> [ type | 'immed' | 'addr' ] + ; 'immed' specifies an immediate value; see grammar for "val" above + ; 'addr' specifies a C identifier; name of symbol to be resolved at + ; link time + frange -> ':' val '-' val ; starting to ending bit positions, where + ; where 0 is least significant bit + frange -> (null) ; default range of 31-0 will be assumed + + comment -> [';'|'#'] [char]* + char -> any printable character + ltr -> ['a'..'z'|'A'..'Z'] + dec -> ['0'..'9']* ; value in decimal + hex -> '0x'['0'..'9' | 'a'..'f' | 'A'..'F']* ; value in hexidecimal + + +Examples +======== + +Example 1: + +The table: + + p1 dreg d1 1 ; data register "d1" for COP1 has value 1 + p1 creg c3 3 ; ctrl register "c3" for COP1 has value 3 + p3 func fill 0x1f:24-20 ; function "fill" for COP3 has value 31 and + ; no fields + +will allow the assembler to accept the following coprocessor instructions: + + LWC1 d1,0x100 ($2) + fill + +Here, the general purpose register "$2", and instruction "LWC1", are standard +mnemonics built-in to the MIPS assembler. + + +Example 2: + +The table: + + p3 dreg d3 3 ; data register "d3" for COP3 has value 3 + p3 creg c2 22 ; control register "c2" for COP3 has value 22 + p3 func fee 0x1f:24-20 dreg:17-13 creg:12-8 immed:7-0 + ; function "fee" for COP3 has value 31, and 3 fields + ; consisting of a data register, a control register, + ; and an immediate value. + +will allow the assembler to accept the following coprocessor instruction: + + fee d3,c2,0x1 + +and will emit the object code: + + 31-26 25 24-20 19-18 17-13 12-8 7-0 + COPz CO fun dreg creg immed + 010011 1 11111 00 00011 10110 00000001 + + 0x4ff07601 + + +Example 3: + +The table: + + p3 dreg d3 3 ; data register "d3" for COP3 has value 3 + p3 creg c2 22 ; control register "c2" for COP3 has value 22 + p3 func fuu 0x01f00001 dreg:17-13 creg:12-8 + +will allow the assembler to accept the following coprocessor +instruction: + + fuu d3,c2 + +and will emit the object code: + + 31-26 25 24-20 19-18 17-13 12-8 7-0 + COPz CO fun dreg creg + 010011 1 11111 00 00011 10110 00000001 + + 0x4ff07601 + +In this way, the programmer can force arbitrary bits of an instruction +to have predefined values. + +======================================================================= +Additional notes: + +Encoding of ranges: +To handle more than one bit position range within an instruction, +use 0s to mask out the ranges which don't apply. +May decide to modify the syntax to allow commas separate multiple +ranges within an instruction (range','range). + +Changes in grammar: + The number of parms argument to the function entry +was deleted from the original format such that we now count the fields. + +---- +FIXME! should really change lexical analyzer +to recognize 'dreg' etc. in context sensative way. +Currently function names or mnemonics may be incorrectly parsed as keywords + +FIXME! hex is ambiguous with any digit + +*/ + +#include +#include "itbl-ops.h" + +/* #define DEBUG */ + +#ifdef DEBUG +#ifndef DBG_LVL +#define DBG_LVL 1 +#endif +#else +#define DBG_LVL 0 +#endif + +#if DBG_LVL >= 1 +#define DBG(x) printf x +#else +#define DBG(x) +#endif + +#if DBG_LVL >= 2 +#define DBGL2(x) printf x +#else +#define DBGL2(x) +#endif + +static int sbit, ebit; +static struct itbl_entry *insn=0; +extern int insntbl_line; +int yyparse PARAMS ((void)); +int yylex PARAMS ((void)); +static int yyerror PARAMS ((const char *)); + +%} + +%union + { + char *str; + int num; + int processor; + unsigned long val; + } + +%token DREG CREG GREG IMMED ADDR INSN NUM ID NL PNUM +%type value flags flagexpr +%type number NUM ftype regtype pnum PNUM +%type ID name + +%start insntbl + +%% + +insntbl: + entrys + ; + +entrys: + entry entrys + | + ; + +entry: + pnum regtype name value NL + { + DBG (("line %d: entry pnum=%d type=%d name=%s value=x%x\n", + insntbl_line, $1, $2, $3, $4)); + itbl_add_reg ($1, $2, $3, $4); + } + | pnum INSN name value range flags + { + DBG (("line %d: entry pnum=%d type=INSN name=%s value=x%x", + insntbl_line, $1, $3, $4)); + DBG ((" sbit=%d ebit=%d flags=0x%x\n", sbit, ebit, $6)); + insn=itbl_add_insn ($1, $3, $4, sbit, ebit, $6); + } + fieldspecs NL + | NL + | error NL + ; + +fieldspecs: + ',' fieldspec fieldspecs + | fieldspec fieldspecs + | + ; + +ftype: + regtype + { + DBGL2 (("ftype\n")); + $$ = $1; + } + | ADDR + { + DBGL2 (("addr\n")); + $$ = ADDR; + } + | IMMED + { + DBGL2 (("immed\n")); + $$ = IMMED; + } + ; + +fieldspec: + ftype range flags + { + DBG (("line %d: field type=%d sbit=%d ebit=%d, flags=0x%x\n", + insntbl_line, $1, sbit, ebit, $3)); + itbl_add_operand (insn, $1, sbit, ebit, $3); + } + ; + +flagexpr: + NUM '|' flagexpr + { + $$ = $1 | $3; + } + | '[' flagexpr ']' + { + $$ = $2; + } + | NUM + { + $$ = $1; + } + ; + +flags: + '*' flagexpr + { + DBGL2 (("flags=%d\n", $2)); + $$ = $2; + } + | + { + $$ = 0; + } + ; + +range: + ':' NUM '-' NUM + { + DBGL2 (("range %d %d\n", $2, $4)); + sbit = $2; + ebit = $4; + } + | + { + sbit = 31; + ebit = 0; + } + ; + +pnum: + PNUM + { + DBGL2 (("pnum=%d\n",$1)); + $$ = $1; + } + ; + +regtype: + DREG + { + DBGL2 (("dreg\n")); + $$ = DREG; + } + | CREG + { + DBGL2 (("creg\n")); + $$ = CREG; + } + | GREG + { + DBGL2 (("greg\n")); + $$ = GREG; + } + ; + +name: + ID + { + DBGL2 (("name=%s\n",$1)); + $$ = $1; + } + ; + +number: + NUM + { + DBGL2 (("num=%d\n",$1)); + $$ = $1; + } + ; + +value: + NUM + { + DBGL2 (("val=x%x\n",$1)); + $$ = $1; + } + ; +%% + +static int +yyerror (msg) + const char *msg; +{ + printf ("line %d: %s\n", insntbl_line, msg); + return 0; +} -- cgit v1.2.1