0918a599ae
@kha The VM versions just throw exceptions. They are just stubs to make sure we can compile Lean. I implemented the uint functions in the new runtime, but there are a few missing cases marked with TODO. I needed these builtins to be able to compile the C++ generated code for corelib.
53 lines
2.2 KiB
Text
53 lines
2.2 KiB
Text
/-
|
|
Copyright (c) 2018 Microsoft Corporation. All rights reserved.
|
|
Released under Apache 2.0 license as described in the file LICENSE.
|
|
Authors: Leonardo de Moura
|
|
-/
|
|
prelude
|
|
import init.data.uint init.platform init.data.fin
|
|
|
|
def usize_sz : nat := (2:nat) ^ system.platform.nbits
|
|
structure usize :=
|
|
(val : fin usize_sz)
|
|
|
|
def usize.of_nat (n : nat) : usize := ⟨fin.of_nat n⟩
|
|
def usize.to_nat (n : usize) : nat := n.val.val
|
|
def usize.add (a b : usize) : usize := ⟨a.val + b.val⟩
|
|
def usize.sub (a b : usize) : usize := ⟨a.val - b.val⟩
|
|
def usize.mul (a b : usize) : usize := ⟨a.val * b.val⟩
|
|
def usize.div (a b : usize) : usize := ⟨a.val / b.val⟩
|
|
def usize.mod (a b : usize) : usize := ⟨a.val % b.val⟩
|
|
def usize.modn (a : usize) (n : nat) : usize := ⟨a.val %ₙ n⟩
|
|
def usize.lt (a b : usize) : Prop := a.val < b.val
|
|
def usize.le (a b : usize) : Prop := a.val ≤ b.val
|
|
|
|
instance : has_zero usize := ⟨usize.of_nat 0⟩
|
|
instance : has_one usize := ⟨usize.of_nat 1⟩
|
|
instance : has_add usize := ⟨usize.add⟩
|
|
instance : has_sub usize := ⟨usize.sub⟩
|
|
instance : has_mul usize := ⟨usize.mul⟩
|
|
instance : has_mod usize := ⟨usize.mod⟩
|
|
instance : has_modn usize := ⟨usize.modn⟩
|
|
instance : has_div usize := ⟨usize.div⟩
|
|
instance : has_lt usize := ⟨usize.lt⟩
|
|
instance : has_le usize := ⟨usize.le⟩
|
|
instance : inhabited usize := ⟨0⟩
|
|
|
|
def usize.dec_eq (a b : usize) : decidable (a = b) :=
|
|
usize.cases_on a $ λ n, usize.cases_on b $ λ m,
|
|
if h : n = m then is_true (h ▸ rfl) else is_false (λ h', usize.no_confusion h' (λ h', absurd h' h))
|
|
|
|
def usize.dec_lt (a b : usize) : decidable (a < b) :=
|
|
usize.cases_on a $ λ n, usize.cases_on b $ λ m,
|
|
infer_instance_as (decidable (n < m))
|
|
|
|
def usize.dec_le (a b : usize) : decidable (a ≤ b) :=
|
|
usize.cases_on a $ λ n, usize.cases_on b $ λ m,
|
|
infer_instance_as (decidable (n <= m))
|
|
|
|
instance : decidable_eq usize := {dec_eq := usize.dec_eq}
|
|
instance usize.has_decidable_lt (a b : usize) : decidable (a < b) := usize.dec_lt a b
|
|
instance usize.has_decidable_le (a b : usize) : decidable (a ≤ b) := usize.dec_le a b
|
|
|
|
theorem usize.modn_lt {m : nat} : ∀ (u : usize), m > 0 → usize.to_nat (u %ₙ m) < m
|
|
| ⟨u⟩ h := fin.modn_lt u h
|