rayoko/src/codegen.zig

86 lines
2.7 KiB
Zig

const std = @import("std");
const ast = @import("ast.zig");
const llvm = @import("llvm.zig");
pub const Codegen = struct {
allocator: *std.mem.Allocator,
pub fn init(allocator: *std.mem.Allocator) Codegen {
return Codegen{ .allocator = allocator };
}
fn genNode(
self: *Codegen,
mod: llvm.LLVMModuleRef,
node: *const ast.Node,
) !void {
switch (node.*) {
.Root => @panic("Should not have gotten Root"),
.FnDecl => |decl| {
const name = decl.func_name.lexeme;
const name_cstr = try std.cstr.addNullByte(self.allocator, name);
errdefer self.allocator.free(name_cstr);
//const ret_type = decl.return_type.lexeme;
var param_types = llvm.LLVMTypeList.init(self.allocator);
errdefer param_types.deinit();
for (decl.params.toSlice()) |param| {
try param_types.append(llvm.LLVMInt32Type());
}
var ret_type = llvm.LLVMFunctionType(
llvm.LLVMInt32Type(),
param_types.toSlice().ptr,
@intCast(c_uint, param_types.len),
0,
);
var func = llvm.LLVMAddFunction(mod, name_cstr.ptr, ret_type);
var entry = llvm.LLVMAppendBasicBlock(func, c"entry");
var builder = llvm.LLVMCreateBuilder();
llvm.LLVMPositionBuilderAtEnd(builder, entry);
// TODO codegen decl.body
var tmp = llvm.LLVMBuildAdd(
builder,
llvm.LLVMGetParam(func, 0),
llvm.LLVMGetParam(func, 1),
c"tmp",
);
_ = llvm.LLVMBuildRet(builder, tmp);
std.debug.warn("cgen: fn decl done\n");
},
else => {
std.debug.warn("got unhandled Node {}\n", node.*);
unreachable;
},
}
}
pub fn gen(self: *Codegen, root: *ast.Node) !void {
std.debug.warn("cgen: start gen\n");
var mod = llvm.LLVMModuleCreateWithName(c"awoo");
defer llvm.LLVMDisposeModule(mod);
std.debug.warn("cgen: got mod\n");
for (root.Root.toSlice()) |child| {
std.debug.warn("cgen: gen child {}\n", child);
try self.genNode(mod, &child);
}
std.debug.warn("cgen: done\n");
var err: ?[*]u8 = null;
_ = llvm.LLVMVerifyModule(
mod,
llvm.LLVMVerifierFailureAction.LLVMAbortProcessAction,
&err,
);
llvm.LLVMDisposeMessage(err);
}
};