Commit 925c805d4b
Changed files (8)
src/codegen.cpp
@@ -26,9 +26,14 @@ struct CodeGen {
HashMap<Buf *, LLVMValueRef, buf_hash, buf_eql_buf> str_table;
};
+struct TypeNode {
+ LLVMTypeRef type_ref;
+ bool is_unreachable;
+};
+
struct CodeGenNode {
union {
- LLVMTypeRef type_ref; // for NodeTypeType
+ TypeNode type_node; // for NodeTypeType
} data;
};
@@ -54,9 +59,16 @@ static void add_node_error(CodeGen *g, AstNode *node, Buf *msg) {
static LLVMTypeRef to_llvm_type(AstNode *type_node) {
assert(type_node->type == NodeTypeType);
assert(type_node->codegen_node);
- assert(type_node->codegen_node->data.type_ref);
+ assert(type_node->codegen_node->data.type_node.type_ref);
- return type_node->codegen_node->data.type_ref;
+ return type_node->codegen_node->data.type_node.type_ref;
+}
+
+
+static bool type_is_unreachable(AstNode *type_node) {
+ assert(type_node->type == NodeTypeType);
+ return type_node->data.type.type == AstNodeTypeTypePrimitive &&
+ buf_eql_str(&type_node->data.type.primitive_name, "unreachable");
}
static void analyze_node(CodeGen *g, AstNode *node) {
@@ -83,13 +95,18 @@ static void analyze_node(CodeGen *g, AstNode *node) {
AstNode *param_type = param_node->data.param_decl.type;
fn_param_values[param_i] = to_llvm_type(param_type);
}
- LLVMTypeRef return_type = to_llvm_type(fn_proto->data.fn_proto.return_type);
+ AstNode *return_type_node = fn_proto->data.fn_proto.return_type;
+ LLVMTypeRef return_type = to_llvm_type(return_type_node);
LLVMTypeRef fn_type = LLVMFunctionType(return_type, fn_param_values, params->length, 0);
LLVMValueRef fn_val = LLVMAddFunction(g->mod, buf_ptr(name), fn_type);
LLVMSetLinkage(fn_val, LLVMExternalLinkage);
LLVMSetFunctionCallConv(fn_val, LLVMCCallConv);
+ if (type_is_unreachable(return_type_node)) {
+ LLVMAddFunctionAttr(fn_val, LLVMNoReturnAttribute);
+ }
+
FnTableEntry *fn_table_entry = allocate<FnTableEntry>(1);
fn_table_entry->fn_value = fn_val;
fn_table_entry->proto_node = fn_proto;
@@ -131,33 +148,43 @@ static void analyze_node(CodeGen *g, AstNode *node) {
analyze_node(g, node->data.param_decl.type);
break;
case NodeTypeType:
- node->codegen_node = allocate<CodeGenNode>(1);
- switch (node->data.type.type) {
- case AstNodeTypeTypePrimitive:
- {
- Buf *name = &node->data.type.primitive_name;
- if (buf_eql_str(name, "u8")) {
- node->codegen_node->data.type_ref = LLVMInt8Type();
- } else if (buf_eql_str(name, "i32")) {
- node->codegen_node->data.type_ref = LLVMInt32Type();
- } else if (buf_eql_str(name, "void")) {
- node->codegen_node->data.type_ref = LLVMVoidType();
- } else {
- add_node_error(g, node,
- buf_sprintf("invalid type name: '%s'", buf_ptr(name)));
- node->codegen_node->data.type_ref = LLVMInt8Type();
+ {
+ node->codegen_node = allocate<CodeGenNode>(1);
+ TypeNode *type_node = &node->codegen_node->data.type_node;
+ switch (node->data.type.type) {
+ case AstNodeTypeTypePrimitive:
+ {
+ Buf *name = &node->data.type.primitive_name;
+ if (buf_eql_str(name, "u8")) {
+ type_node->type_ref = LLVMInt8Type();
+ } else if (buf_eql_str(name, "i32")) {
+ type_node->type_ref = LLVMInt32Type();
+ } else if (buf_eql_str(name, "void")) {
+ type_node->type_ref = LLVMVoidType();
+ } else if (buf_eql_str(name, "unreachable")) {
+ type_node->type_ref = LLVMVoidType();
+ type_node->is_unreachable = true;
+ } else {
+ add_node_error(g, node,
+ buf_sprintf("invalid type name: '%s'", buf_ptr(name)));
+ type_node->type_ref = LLVMVoidType();
+ }
+ break;
}
- break;
- }
- case AstNodeTypeTypePointer:
- {
- analyze_node(g, node->data.type.child_type);
- node->codegen_node->data.type_ref = LLVMPointerType(
- node->data.type.child_type->codegen_node->data.type_ref, 0);
- break;
- }
+ case AstNodeTypeTypePointer:
+ {
+ analyze_node(g, node->data.type.child_type);
+ TypeNode *child_type_node = &node->data.type.child_type->codegen_node->data.type_node;
+ if (child_type_node->is_unreachable) {
+ add_node_error(g, node,
+ buf_create_from_str("pointer to unreachable not allowed"));
+ }
+ type_node->type_ref = LLVMPointerType(child_type_node->type_ref, 0);
+ break;
+ }
+ }
+ break;
}
- break;
case NodeTypeBlock:
for (int i = 0; i < node->data.block.statements.length; i += 1) {
AstNode *child = node->data.block.statements.at(i);
@@ -183,6 +210,8 @@ static void analyze_node(CodeGen *g, AstNode *node) {
case AstNodeExpressionTypeFnCall:
analyze_node(g, node->data.expression.data.fn_call);
break;
+ case AstNodeExpressionTypeUnreachable:
+ break;
}
break;
case NodeTypeFnCall:
@@ -235,7 +264,11 @@ static LLVMValueRef gen_fn_call(CodeGen *g, AstNode *fn_call_node) {
LLVMValueRef result = LLVMBuildCall(g->builder, fn_table_entry->fn_value,
param_values, actual_param_count, "");
- return result;
+ if (type_is_unreachable(fn_table_entry->proto_node->data.fn_proto.return_type)) {
+ return LLVMBuildUnreachable(g->builder);
+ } else {
+ return result;
+ }
}
static LLVMValueRef find_or_create_string(CodeGen *g, Buf *str) {
@@ -280,6 +313,8 @@ static LLVMValueRef gen_expr(CodeGen *g, AstNode *expr_node) {
}
case AstNodeExpressionTypeFnCall:
return gen_fn_call(g, expr_node->data.expression.data.fn_call);
+ case AstNodeExpressionTypeUnreachable:
+ return LLVMBuildUnreachable(g->builder);
}
zig_unreachable();
}
@@ -333,6 +368,10 @@ void code_gen(CodeGen *g) {
LLVMTypeRef function_type = LLVMFunctionType(ret_type, param_types, fn_proto->params.length, 0);
LLVMValueRef fn = LLVMAddFunction(g->mod, buf_ptr(&fn_proto->name), function_type);
+ if (type_is_unreachable(fn_proto->return_type)) {
+ LLVMAddFunctionAttr(fn, LLVMNoReturnAttribute);
+ }
+
LLVMBasicBlockRef entry_block = LLVMAppendBasicBlock(fn, "entry");
LLVMPositionBuilderAtEnd(g->builder, entry_block);
src/main.cpp
@@ -102,7 +102,8 @@ static int build(const char *arg0, const char *in_file, const char *out_file, Zi
} else {
for (int i = 0; i < errors->length; i += 1) {
ErrorMsg *err = &errors->at(i);
- fprintf(stderr, "Error: Line %d, column %d: %s\n", err->line_start, err->column_start,
+ fprintf(stderr, "Error: Line %d, column %d: %s\n",
+ err->line_start + 1, err->column_start + 1,
buf_ptr(err->msg));
}
return 1;
@@ -115,6 +116,7 @@ static int build(const char *arg0, const char *in_file, const char *out_file, Zi
fprintf(stderr, "\nLink:\n");
fprintf(stderr, "------------------\n");
code_gen_link(codegen, false, out_file);
+ fprintf(stderr, "OK\n");
return 0;
}
src/parser.cpp
@@ -236,7 +236,7 @@ static void ast_expect_token(ParseContext *pc, Token *token, TokenId token_id) {
}
/*
-Type : token(Symbol) | PointerType;
+Type : token(Symbol) | PointerType | token(Unreachable)
PointerType : token(Star) token(Const) Type | token(Star) token(Mut) Type;
*/
static AstNode *ast_parse_type(ParseContext *pc, int token_index, int *new_token_index) {
@@ -245,7 +245,10 @@ static AstNode *ast_parse_type(ParseContext *pc, int token_index, int *new_token
AstNode *node = ast_create_node(NodeTypeType, token);
- if (token->id == TokenIdSymbol) {
+ if (token->id == TokenIdKeywordUnreachable) {
+ node->data.type.type = AstNodeTypeTypePrimitive;
+ buf_init_from_str(&node->data.type.primitive_name, "unreachable");
+ } else if (token->id == TokenIdSymbol) {
node->data.type.type = AstNodeTypeTypePrimitive;
ast_buf_from_token(pc, token, &node->data.type.primitive_name);
} else if (token->id == TokenIdStar) {
@@ -373,10 +376,16 @@ static AstNode *ast_parse_fn_call(ParseContext *pc, int token_index, int *new_to
return node;
}
+/*
+Expression : token(Number) | token(String) | token(Unreachable) | FnCall
+*/
static AstNode *ast_parse_expression(ParseContext *pc, int token_index, int *new_token_index) {
Token *token = &pc->tokens->at(token_index);
AstNode *node = ast_create_node(NodeTypeExpression, token);
- if (token->id == TokenIdSymbol) {
+ if (token->id == TokenIdKeywordUnreachable) {
+ node->data.expression.type = AstNodeExpressionTypeUnreachable;
+ token_index += 1;
+ } else if (token->id == TokenIdSymbol) {
node->data.expression.type = AstNodeExpressionTypeFnCall;
node->data.expression.data.fn_call = ast_parse_fn_call(pc, token_index, &token_index);
} else if (token->id == TokenIdNumberLiteral) {
@@ -402,7 +411,7 @@ ExpressionStatement : Expression token(Semicolon) ;
ReturnStatement : token(Return) Expression token(Semicolon) ;
-Expression : token(Number) | token(String) | FnCall ;
+Expression : token(Number) | token(String) | token(Unreachable) | FnCall
FnCall : token(Symbol) token(LParen) list(Expression, token(Comma)) token(RParen) ;
*/
@@ -420,6 +429,7 @@ static AstNode *ast_parse_statement(ParseContext *pc, int token_index, int *new_
ast_expect_token(pc, semicolon, TokenIdSemicolon);
} else if (token->id == TokenIdSymbol ||
token->id == TokenIdStringLiteral ||
+ token->id == TokenIdKeywordUnreachable ||
token->id == TokenIdNumberLiteral)
{
node->data.statement.type = AstNodeStatementTypeExpression;
src/parser.hpp
@@ -94,6 +94,7 @@ enum AstNodeExpressionType {
AstNodeExpressionTypeNumber,
AstNodeExpressionTypeString,
AstNodeExpressionTypeFnCall,
+ AstNodeExpressionTypeUnreachable,
};
struct AstNodeExpression {
src/tokenizer.cpp
@@ -152,6 +152,8 @@ static void end_token(Tokenize *t) {
t->cur_tok->id = TokenIdKeywordConst;
} else if (mem_eql_str(token_mem, token_len, "extern")) {
t->cur_tok->id = TokenIdKeywordExtern;
+ } else if (mem_eql_str(token_mem, token_len, "unreachable")) {
+ t->cur_tok->id = TokenIdKeywordUnreachable;
}
t->cur_tok = nullptr;
@@ -311,6 +313,7 @@ static const char * token_name(Token *token) {
case TokenIdKeywordMut: return "Mut";
case TokenIdKeywordReturn: return "Return";
case TokenIdKeywordExtern: return "Extern";
+ case TokenIdKeywordUnreachable: return "Unreachable";
case TokenIdLParen: return "LParen";
case TokenIdRParen: return "RParen";
case TokenIdComma: return "Comma";
src/tokenizer.hpp
@@ -18,6 +18,7 @@ enum TokenId {
TokenIdKeywordMut,
TokenIdKeywordConst,
TokenIdKeywordExtern,
+ TokenIdKeywordUnreachable,
TokenIdLParen,
TokenIdRParen,
TokenIdComma,
test/hello.zig
@@ -1,9 +1,9 @@
extern {
fn puts(s: *mut u8) -> i32;
- fn exit(code: i32);
+ fn exit(code: i32) -> unreachable;
}
-fn _start() {
+fn _start() -> unreachable {
puts("Hello, world!");
exit(0);
}
README.md
@@ -40,8 +40,6 @@ readable, safe, optimal, and concise code to solve any computing problem.
## Roadmap
- * Hello, world.
- - Produce .o file.
* Produce executable file instead of .o file.
* Add debugging symbols.
* Debug/Release mode.
@@ -87,7 +85,7 @@ ParamDeclList : token(LParen) list(ParamDecl, token(Comma)) token(RParen)
ParamDecl : token(Symbol) token(Colon) Type
-Type : token(Symbol) | PointerType
+Type : token(Symbol) | PointerType | token(Unreachable)
PointerType : token(Star) token(Const) Type | token(Star) token(Mut) Type
@@ -99,7 +97,7 @@ ExpressionStatement : Expression token(Semicolon)
ReturnStatement : token(Return) Expression token(Semicolon)
-Expression : token(Number) | token(String) | FnCall
+Expression : token(Number) | token(String) | token(Unreachable) | FnCall
FnCall : token(Symbol) token(LParen) list(Expression, token(Comma)) token(RParen)
```