ref: c3a430e6824a8f1f08f28a8df24b4b64266b06f9
dir: /sys/src/cmd/1a/a.y/
%{ #include "a.h" %} %union { Sym *sym; long lval; double dval; char sval[8]; Addr addr; Gen gen; Gen2 gen2; } %left '|' %left '^' %left '&' %left '<' '>' %left '+' '-' %left '*' '/' '%' %token <lval> LTYPE1 LTYPE2 LTYPE3 LTYPE4 LTYPE5 %token <lval> LTYPE6 LTYPE7 LTYPE8 LTYPE9 LTYPEA LTYPEB %token <lval> LCONST LSP LSB LFP LPC LTOS LAREG LDREG LFREG %token <dval> LFCONST %token <sval> LSCONST %token <sym> LNAME LLAB LVAR %type <lval> con expr type pointer reg offset %type <addr> name areg %type <gen> gen rel %type <gen2> noaddr gengen dstgen spec1 spec2 spec3 srcgen dstrel genrel %% prog: | prog line line: LLAB ':' { if($1->value != pc) yyerror("redeclaration of %s", $1->name); $1->value = pc; } line | LNAME ':' { $1->type = LLAB; $1->value = pc; } line | ';' | inst ';' | error ';' inst: LNAME '=' expr { $1->type = LVAR; $1->value = $3; } | LVAR '=' expr { if($1->value != $3) yyerror("redeclaration of %s", $1->name); $1->value = $3; } | LTYPE1 gengen { outcode($1, &$2); } | LTYPE2 noaddr { outcode($1, &$2); } | LTYPE3 dstgen { outcode($1, &$2); } | LTYPE4 spec1 { outcode($1, &$2); } | LTYPE5 srcgen { outcode($1, &$2); } | LTYPE6 dstrel { outcode($1, &$2); } | LTYPE7 genrel { outcode($1, &$2); } | LTYPE8 dstgen { outcode($1, &$2); } | LTYPE8 gengen { outcode($1, &$2); } | LTYPE9 noaddr { outcode($1, &$2); } | LTYPE9 dstgen { outcode($1, &$2); } | LTYPEA spec2 { outcode($1, &$2); } | LTYPEB spec3 { outcode($1, &$2); } noaddr: { $$.from = nullgen; $$.to = nullgen; } | ',' { $$.from = nullgen; $$.to = nullgen; } srcgen: gen { $$.from = $1; $$.to = nullgen; } | gen ',' { $$.from = $1; $$.to = nullgen; } dstgen: gen { $$.from = nullgen; $$.to = $1; } | ',' gen { $$.from = nullgen; $$.to = $2; } gengen: gen ',' gen { $$.from = $1; $$.to = $3; } dstrel: rel { $$.from = nullgen; $$.to = $1; } | ',' rel { $$.from = nullgen; $$.to = $2; } genrel: gen ',' rel { $$.from = $1; $$.to = $3; } spec1: /* DATA opcode */ gen '/' con ',' gen { $1.displace = $3; $$.from = $1; $$.to = $5; } spec2: /* bit field opcodes */ gen ',' gen ',' con ',' con { $1.field = $7; $3.field = $5; $$.from = $1; $$.to = $3; } spec3: /* TEXT opcode */ gengen | gen ',' con ',' gen { $1.displace = $3; $$.from = $1; $$.to = $5; } rel: con '(' LPC ')' { $$ = nullgen; $$.type = D_BRANCH; $$.offset = $1 + pc; } | LNAME offset { $$ = nullgen; if(pass == 2) yyerror("undefined label: %s", $1->name); $$.type = D_BRANCH; $$.sym = $1; $$.offset = $2; } | LLAB offset { $$ = nullgen; $$.type = D_BRANCH; $$.sym = $1; $$.offset = $1->value + $2; } gen: type { $$ = nullgen; $$.type = $1; } | '$' con { $$ = nullgen; $$.type = D_CONST; $$.offset = $2; } | '$' name { $$ = nullgen; { Addr *a; a = &$$; *a = $2; } if($2.type == D_AUTO || $2.type == D_PARAM) yyerror("constant cannot be automatic: %s", $2.sym->name); $$.type = $2.type | I_ADDR; } | '$' LSCONST { $$ = nullgen; $$.type = D_SCONST; memcpy($$.sval, $2, sizeof($$.sval)); } | '$' LFCONST { $$ = nullgen; $$.type = D_FCONST; $$.dval = $2; } | '$' '-' LFCONST { $$ = nullgen; $$.type = D_FCONST; $$.dval = -$3; } | LTOS '+' con { $$ = nullgen; $$.type = D_STACK; $$.offset = $3; } | LTOS '-' con { $$ = nullgen; $$.type = D_STACK; $$.offset = -$3; } | con { $$ = nullgen; $$.type = D_CONST | I_INDIR; $$.offset = $1; } | '-' '(' LAREG ')' { $$ = nullgen; $$.type = $3 | I_INDDEC; } | '(' LAREG ')' '+' { $$ = nullgen; $$.type = $2 | I_INDINC; } | areg { $$ = nullgen; $$.type = $1.type; { Addr *a; a = &$$; *a = $1; } } type: reg | LFREG reg: LAREG | LDREG | LTOS areg: '(' LAREG ')' { $$.type = $2 | I_INDIR; $$.sym = S; $$.offset = 0; } | con '(' LAREG ')' { $$.type = $3 | I_INDIR; $$.sym = S; $$.offset = $1; } | '(' ')' { $$.type = D_NONE | I_INDIR; $$.sym = S; $$.offset = 0; } | con '(' ')' { $$.type = D_NONE | I_INDIR; $$.sym = S; $$.offset = $1; } | name name: LNAME offset '(' pointer ')' { $$.type = $4; $$.sym = $1; $$.offset = $2; } | LNAME '<' '>' offset '(' LSB ')' { $$.type = D_STATIC; $$.sym = $1; $$.offset = $4; } offset: { $$ = 0; } | '+' con { $$ = $2; } | '-' con { $$ = -$2; } pointer: LSB | LSP | LFP con: LCONST | LVAR { $$ = $1->value; } | '-' con { $$ = -$2; } | '+' con { $$ = $2; } | '~' con { $$ = ~$2; } | '(' expr ')' { $$ = $2; } expr: con | expr '+' expr { $$ = $1 + $3; } | expr '-' expr { $$ = $1 - $3; } | expr '*' expr { $$ = $1 * $3; } | expr '/' expr { $$ = $1 / $3; } | expr '%' expr { $$ = $1 % $3; } | expr '<' '<' expr { $$ = $1 << $4; } | expr '>' '>' expr { $$ = $1 >> $4; } | expr '&' expr { $$ = $1 & $3; } | expr '^' expr { $$ = $1 ^ $3; } | expr '|' expr { $$ = $1 | $3; }