stage2: add initial implementation of func arguments in LLVM backend

The following works:
```
export fn _start() noreturn {
    assert(true);
    exit();
}

fn assert(cond: bool) void {}

fn exit() noreturn {
    unreachable;
}
```

1 files changed, 9 insertions, 0 deletions

diff --git a/src/llvm_bindings.zig b/src/llvm_bindings.zig
index e36d71b312..388acc4ba2 100644
--- a/src/llvm_bindings.zig
+++ b/src/llvm_bindings.zig
@@ -36,6 +36,15 @@ pub const ValueRef = opaque {
 pub const TypeRef = opaque {
     pub const functionType = LLVMFunctionType;
     extern fn LLVMFunctionType(ReturnType: *const TypeRef, ParamTypes: ?[*]*const TypeRef, ParamCount: c_uint, IsVarArg: LLVMBool) *const TypeRef;
+
+    pub const constNull = LLVMConstNull;
+    extern fn LLVMConstNull(Ty: *const TypeRef) *const ValueRef;
+
+    pub const constAllOnes = LLVMConstAllOnes;
+    extern fn LLVMConstAllOnes(Ty: *const TypeRef) *const ValueRef;
+
+    pub const getUndef = LLVMGetUndef;
+    extern fn LLVMGetUndef(Ty: *const TypeRef) *const ValueRef;
 };
 
 pub const ModuleRef = opaque {