《編譯原理(實(shí)驗(yàn)部分)》實(shí)驗(yàn)3_PL0語(yǔ)法分析

1、編譯原理（實(shí)驗(yàn)部分）實(shí)驗(yàn)3_PL0語(yǔ)法分析一、實(shí)驗(yàn)?zāi)康募由詈挽柟虒?duì)于語(yǔ)法分析的了解和掌握；給出PL/0文法規(guī)范，要求編寫(xiě)PL/0語(yǔ)言的語(yǔ)法分析程序。二、實(shí)驗(yàn)設(shè)備1、PC 兼容機(jī)一臺(tái)；操作系統(tǒng)為WindowsWindowsXP。2、Visual C+ 6.0 或以上版本， Windows 2000 或以上版本，匯編工具（在Software 子目錄下）。三、實(shí)驗(yàn)原理PL/O語(yǔ)言的編譯程序，是用高級(jí)語(yǔ)言PASCAL語(yǔ)言書(shū)寫(xiě)的。整個(gè)編譯過(guò)程是由一些嵌套及并列的過(guò)程或函數(shù)完成。語(yǔ)法分析是由過(guò)程BLOCK完成。采用自頂向下的遞歸子程序法。所產(chǎn)生的目標(biāo)程序?yàn)榧傧髼Ｊ接?jì)算機(jī)的匯編語(yǔ)言。對(duì)目標(biāo)程序的執(zhí)行是由PA

2、SCAL語(yǔ)言書(shū)寫(xiě)的解釋程序進(jìn)行的。四、實(shí)驗(yàn)步驟實(shí)驗(yàn)代碼int lp=0;int rp=0;#define getsymdo if(-1=getsym() return -1#define expressiondo() if(-1=expression() return -1#define termdo() if(-1=term() return -1#define factordo() if(-1=factor() return -1int expression();/語(yǔ)法分析int factor()if(sym!=ident &sym!=number&sym!=lparen) err+;if

3、(err=1) printf(語(yǔ)法錯(cuò)誤: n);printf(error-Factor Needs Ident or Number or Lparenn);if (sym = ident) | (sym = number) | (sym = lparen) if (sym = ident) WordAnalyse();if(getsym()=-1)return -1;if(sym!=times&sym!=slash&sym!=plus&sym!=minus&sym!=rparen)err+;if(err=1) printf(語(yǔ)法錯(cuò)誤: n);printf(變量后沒(méi)有跟上+-* n);if(lp

4、=0 & sym=rparen)err+;if(err=1) printf(語(yǔ)法錯(cuò)誤: n);printf(沒(méi)有左括號(hào)匹配n);else if (sym = number)WordAnalyse();if(getsym()=-1)return -1;if(sym!=times&sym!=slash&sym!=plus&sym!=minus&sym!=rparen)err+;if(err=1) printf(語(yǔ)法錯(cuò)誤: n);printf(數(shù)字后沒(méi)有跟上+-* n);if(lp=0 & sym=rparen)err+;if(err=1) printf(語(yǔ)法錯(cuò)誤: n);printf(沒(méi)有左括號(hào)匹

5、配n);else if (sym = lparen)WordAnalyse();lp+;if(getsym()=-1) lp-;err+;if(err=1) printf(語(yǔ)法錯(cuò)誤: n);printf(error-Needs Rparen n);return -1;expressiondo();if (sym = rparen)WordAnalyse();lp-;if(getsym()=-1)return -1;if(sym!=times&sym!=slash&sym!=plus&sym!=minus)err+;if(err=1) printf(語(yǔ)法錯(cuò)誤: n);printf(括號(hào)后沒(méi)有跟上

6、+-* n);elseerr+;if(err=1) printf(語(yǔ)法錯(cuò)誤: n);printf(error-Needs Rparen n);return 0;int term()factordo();if(sym!=times&sym!=slash&sym!=plus&sym!=minus&sym!=ident&sym!=number&sym!=lparen&sym!=rparen) err+;if(err=1) printf(語(yǔ)法錯(cuò)誤: n);printf(不能識(shí)別字符n);while (sym = times) | (sym = slash)WordAnalyse();if(getsym

7、()=-1) err+;if(err=1) printf(語(yǔ)法錯(cuò)誤: n);printf(* 后缺項(xiàng)n);return -1;factordo();return 0;int expression()if (sym = plus) | (sym = minus)/coutstrlen(ID)endl;if (sym=minus&2=strlen(ID)+1)flg=1;else flg=0;WordAnalyse();getsymdo;termdo();else/WordAnalyse();termdo();if(sym!=times&sym!=slash&sym!=plus&sym!=minus&sym!=ident&sym!=number&sym!=lparen&sym!=rparen) err+;if(err=1) printf(語(yǔ)法錯(cuò)誤: n);printf(不能識(shí)別字符n);while (sym = plus) | (sym = minus)WordAnalyse();if(getsym()=-1) err+;if(err=1) printf(語(yǔ)法錯(cuò)誤: n);printf(+ - 后缺項(xiàng)n);return -1;termdo();return 0;int main(int argc, char* argv)init();err=0;if