Ubuntu20.04 + llvm20
构建步骤
git clone git@github.com:iiicp/subc-llvm.git
cd subc-llvm
mkdir build && cd build
cmake .. -GNinja -DLLVM_DIR=`llvm install home`/lib/cmake/llvm
ninja
目前在下列环境下编译通过：
- Ubuntu 20.04 + llvm 20
- Ubuntu 22.04 + llvm 20
- MacOS 14 + llvm 20
prog ::= external-decl+
external-decl ::= func-def | decl-stmt
func-def ::= decl-spec declarator block-stmt
block-stmt ::= stmt*
stmt ::= decl-stmt | expr-stmt | null-stmt | if-stmt | block-stmt | for-stmt |
break-stmt | continue-stmt | while-stmt | do-while-stm | switch-stmt |
case-stmt | default-stmt
decl-stmt ::= decl-spec init-declarator-list? ";"
init-declarator-list ::= declarator (= initializer)? ("," declarator (= initializer)?)*
decl-spec ::= "int" | struct-or-union-specifier
struct-or-union-specifier ::= struct-or-union identifier "{" (decl-spec declarator(, declarator)* ";")* "}"
struct-or-union identifier
struct-or-union := "struct" | "union"
declarator ::= "*"* direct-declarator
direct-declarator ::= identifier | direct-declarator "[" assign "]"
| direct-declarator "(" parameter-type-list? ")"
parameter-type-list ::= decl-spec declarator (, decl-spec declarator)* (", " "...")?
initializer ::= assign | "{" initializer ("," initializer)* "}"
null-stmt ::= ";"
if-stmt ::= "if" "(" expr ")" stmt ( "else" stmt )?
for-stmt ::= "for" "(" expr? ";" expr? ";" expr? ")" stmt
"for" "(" decl-stmt expr? ";" expr? ")" stmt
while-stmt ::= "while" "(" expr ")" stmt
do-while-stmt ::= "do" stmt "while" "(" expr ")" ";"
switch-stmt ::= "switch" "(" expr ")" stmt
case-stmt ::= "case" expr ":" stmt
default-stmt ::= "default" ":" stmt
block-stmt ::= "{" stmt* "}"
break-stmt ::= "break" ";"
continue-stmt ::= "continue" ";"
expr-stmt ::= expr ";"
expr ::= assign (, assign )*
assign ::= conditional ("="|"+="|"-="|"*="|"/="|"%="|"<<="|">>="|"&="|"^="|"|=" asign)?
conditional ::= logor ("?" expr ":" conditional)?
logor ::= logand ("||" logand)*
logand ::= bitor ("&&" bitor)*
bitor ::= bitxor ("|" bitxor)*
bitxor ::= bitand ("^" bitand)*
bitand ::= equal ("&" equal)*
equal ::= relational ("==" | "!=" relational)*
relational ::= shift ("<"|">"|"<="|">=" shift)*
shift ::= add ("<<" | ">>" add)*
add ::= mult ("+" | "-" mult)*
mult ::= cast ("*" | "/" | "%" cast)*
cast ::= unary | "(" type-name ")" cast
unary ::= postfix | ("++"|"--"|"&"|"*"|"+"|"-"|"~"|"!"|"sizeof") unary
| "sizeof" "(" type-name ")"
postfix ::= primary | postfix ("++"|"--") | postfix "[" expr "]"
| postfix "." identifier
| postfix "->" identifier
| postfix "(" arg-expr-list? ")"
arg-expr-list := assign ("," assign)*
primary ::= identifier | number | "(" expr ")"
number ::= ([0-9])+
identifier ::= (a-zA-Z_)(a-zA-Z0-9_)*
type-name ::= decl-spec abstract-declarator?
abstract-declarator ::= "*"* direct-abstract-declarator?
direct-abstract-declarator ::= direct-abstract-declarator? "[" assign "]"
struct {
int a, b;
struct {int d; int a;} c;
} a = {1,2, {10}};
int sum(int n) {
int ret = 0;
for (int i = 0; i <= n; ++i) {
ret += i;
}
return ret;
}
int main() {
return a.c.d + sum(100);
}
// How to run:
//
// $ ./9cc examples/nqueen.c > tmp-nqueen.s
// $ gcc -static -o tmp-nqueen tmp-nqueen.s
// $ ./tmp-nqueen
int printf(const char *fmg, ...);
void print_board(int board[][10]) {
for (int i = 0; i < 10; i++) {
for (int j = 0; j < 10; j++)
if (board[i][j])
printf("Q ");
else
printf(". ");
printf("\n");
}
printf("\n\n");
}
int conflict(int board[][10], int row, int col) {
for (int i = 0; i < row; i++) {
if (board[i][col])
return 1;
int j = row - i;
if (0 < col - j + 1 && board[i][col - j])
return 1;
if (col + j < 10 && board[i][col + j])
return 1;
}
return 0;
}
void solve(int board[][10], int row) {
if (row > 9) {
print_board(board);
}
for (int i = 0; i < 10; i++) {
if (conflict(board, row, i)) {
} else {
board[row][i] = 1;
solve(board, row + 1);
board[row][i] = 0;
}
}
}
int main() {
int board[100];
for (int i = 0; i < 100; i++)
board[i] = 0;
solve(board, 0);
return 0;
}