From 702ed9c1fd77a999c4b8a922ef11c8e7dcddee7f Mon Sep 17 00:00:00 2001
From: zjx <zjx@zjx.>
Date: Thu, 19 Mar 2026 19:46:19 +0800
Subject: [PATCH] =?UTF-8?q?feat(antlr4)=EF=BC=9A=E8=AF=AD=E6=B3=95?=
 =?UTF-8?q?=E6=A0=91=E6=9E=84=E5=BB=BA=E7=9A=84=E7=9B=B8=E5=85=B3=E4=BB=A3?=
 =?UTF-8?q?=E7=A0=81=E4=BF=AE=E6=94=B9?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/antlr4/SysY.g4 | 209 +++++++++++++++++++++++++++++++++------------
 1 file changed, 156 insertions(+), 53 deletions(-)

diff --git a/src/antlr4/SysY.g4 b/src/antlr4/SysY.g4
index 263aeef..38d82a3 100644
--- a/src/antlr4/SysY.g4
+++ b/src/antlr4/SysY.g4
@@ -1,68 +1,70 @@
-// SysY 子集语法：支持形如
-// int main() { int a = 1; int b = 2; return a + b; }
-// 的最小返回表达式编译。
-
-// 后续需要自行添加
-
 grammar SysY;
 
-/*===-------------------------------------------===*/
-/* Lexer rules                                     */
-/*===-------------------------------------------===*/
-
-INT: 'int';
-RETURN: 'return';
-
-ASSIGN: '=';
-ADD: '+';
+// ======================
+// Parser Rules
+// ======================
 
-LPAREN: '(';
-RPAREN: ')';
-LBRACE: '{';
-RBRACE: '}';
-SEMICOLON: ';';
+compUnit
+    : (decl | funcDef)+
+    ;
 
-ID: [a-zA-Z_][a-zA-Z_0-9]*;
-ILITERAL: [0-9]+;
+decl
+    : constDecl
+    | varDecl
+    ;
 
-WS: [ \t\r\n] -> skip;
-LINECOMMENT: '//' ~[\r\n]* -> skip;
-BLOCKCOMMENT: '/*' .*? '*/' -> skip;
+constDecl
+    : 'const' bType constDef (',' constDef)* ';'
+    ;
 
-/*===-------------------------------------------===*/
-/* Syntax rules                                    */
-/*===-------------------------------------------===*/
+bType
+    : 'int'
+    | 'float'
+    ;
 
-compUnit
-    : funcDef EOF
+constDef
+    : Ident ('[' constExp ']')* '=' constInitVal
     ;
 
-decl
-    : btype varDef SEMICOLON
+constInitVal
+    : constExp
+    | '{' (constInitVal (',' constInitVal)*)? '}'
     ;
 
-btype
-    : INT
+varDecl
+    : bType varDef (',' varDef)* ';'
     ;
 
 varDef
-    : lValue (ASSIGN initValue)?
+    : Ident ('[' constExp ']')*
+    | Ident ('[' constExp ']')* '=' initVal
     ;
 
-initValue
+initVal
     : exp
+    | '{' (initVal (',' initVal)*)? '}'
     ;
 
 funcDef
-    : funcType ID LPAREN RPAREN blockStmt
+    : funcType Ident '(' funcFParams? ')' block
     ;
 
 funcType
-    : INT
+    : 'void'
+    | 'int'
+    | 'float'
     ;
 
-blockStmt
-    : LBRACE blockItem* RBRACE
+funcFParams
+    : funcFParam (',' funcFParam)*
+    ;
+
+funcFParam
+    : bType Ident ('[' ']' ('[' exp ']')*)?
+    ;
+
+block
+    : '{' blockItem* '}'
     ;
 
 blockItem
@@ -71,28 +73,129 @@ blockItem
     ;
 
 stmt
-    : returnStmt
+    : lVal '=' exp ';'
+    | exp? ';'
+    | block
+    | 'if' '(' cond ')' stmt ('else' stmt)?
+    | 'while' '(' cond ')' stmt
+    | 'break' ';'
+    | 'continue' ';'
+    | 'return' exp? ';'
     ;
 
-returnStmt
-    : RETURN exp SEMICOLON
+exp
+    : addExp
     ;
 
-exp
-    : LPAREN exp RPAREN          # parenExp
-    | var                        # varExp
-    | number                     # numberExp
-    | exp ADD exp                # additiveExp
+cond
+    : lOrExp
     ;
 
-var
-    : ID
+lVal
+    : Ident ('[' exp ']')*
     ;
 
-lValue
-    : ID
+primaryExp
+    : '(' exp ')'
+    | lVal
+    | number
     ;
 
 number
-    : ILITERAL
+    : FloatConst
+    | IntConst
+    ;
+
+unaryExp
+    : primaryExp
+    | Ident '(' funcRParams? ')'
+    | unaryOp unaryExp
+    ;
+
+unaryOp
+    : '+'
+    | '-'
+    | '!'
     ;
+
+funcRParams
+    : exp (',' exp)*
+    ;
+
+mulExp
+    : unaryExp (('*' | '/' | '%') unaryExp)*
+    ;
+
+addExp
+    : mulExp (('+' | '-') mulExp)*
+    ;
+
+relExp
+    : addExp (('<' | '>' | '<=' | '>=') addExp)*
+    ;
+
+eqExp
+    : relExp (('==' | '!=') relExp)*
+    ;
+
+lAndExp
+    : eqExp ('&&' eqExp)*
+    ;
+
+lOrExp
+    : lAndExp ('||' lAndExp)*
+    ;
+
+constExp
+    : addExp
+    ;
+
+// ======================
+// Lexer Rules
+// ======================
+
+fragment DIGIT : [0-9] ;
+fragment HEXDIGIT : [0-9a-fA-F] ;
+fragment EXP : [eE][+-]? DIGIT+ ;
+fragment PEXP : [pP][+-]? DIGIT+ ;
+
+// Float（含 hex float）
+FloatConst
+    : ('0x' | '0X')
+      (
+        HEXDIGIT+ '.' HEXDIGIT*
+      | '.' HEXDIGIT+
+      | HEXDIGIT+
+      )
+      PEXP
+    | '.' DIGIT+ EXP?
+    | DIGIT+ '.' DIGIT* EXP?
+    | DIGIT+ EXP
+    ;
+
+// Int（完整三种）
+IntConst
+    : '0'
+    | [1-9][0-9]*          // decimal
+    | '0'[0-7]+            // octal
+    | ('0x' | '0X')[0-9a-fA-F]+  // hex
+    ;
+
+// ---------- 标识符 ----------
+Ident
+    : [a-zA-Z_][a-zA-Z0-9_]*
+    ;
+
+// ---------- 空白 ----------
+WS
+    : [ \t\r\n]+ -> skip
+    ;
+
+// ---------- 注释 ----------
+LINE_COMMENT
+    : '//' ~[\r\n]* -> skip
+    ;
+
+BLOCK_COMMENT
+    : '/*' .*? '*/' -> skip
+    ;
\ No newline at end of file