max/lean4-htt
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions 2
lean4-htt/src/Init/Data/UInt.lean
Leonardo de Moura 2120883307 refactor: heterogeneous operators 
@Kha I had some unexpected surprises, but it is a good change.
Here is the summary.

1- We could get rid of `a %ₙ b` and `ModN` class. We can use `HMod`
instead. It was a positive surprise since I didn't remember we had
this `ModN` class.

2- Coercions are never used in heterogeneous operators. This is
expected since `a * b` is now notation for `HMul.hMul a b`, and
`a` and `b` may have different types. I manually added instances such
as `HMul Nat Int Int`. However, I did not try to add generic instances
such as
```
instance [Coe a b] [Mul b] : HMul a b b where
  hMul x y := mul (coe x) y
```
I will try later.

3- Give `h : cs.size > 0`, I got a type error at
```
let idx : Fin cs.size := ⟨cs.size - 1, Nat.predLt h⟩
```
`Nat.predLt h` has type `Nat.pred cs.size < cs.size`
However, `Nat.pred cs.size` doesn't unify with `cs.size - 1`.
The problem is that we can't synthesize the `HSub` instance until
we apply the default instances.
It worked before because `isDefEq` would force the pending TC
problem `Sub Nat` to be resolved, and after that we would be able
to reduce `cs.size - 1` and establish that it is definitionally
equal to `Nat.pred cs.size`.
I considered two possible workarounds
a) `let idx : Fin cs.size := ⟨cs.size - (1:Nat), Nat.predLt h⟩`
b) `let idx : Fin cs.size := ⟨cs.size - 1, by exact Nat.predLt h⟩`
The first one works because we are not providing enough information
for synthesizing the `HSub` instance. The second works because it
postpones the elaboration of `Nat.predLt h`. The default instances
will be applied before we start applying tactics.

4- The `.` notation is affected too. For example, `(x + 1).toUInt8`
doesn't work since we don't know the type of `x+1` until we apply
default instances. I fixed it by using `(x + (1:Nat)).toUInt8`.
Another possible fix is `Nat.toUInt8 (x + 1)`.
Similarly, `(x+1).fold ...` doesn't work.

5- The following code failed to be elaborated
```
indent (push s!"{ss'}\n") (some (0 - Format.getIndent (← getOptions)))
```
It was working before, but it relied on how the expected type is
propagated. The elaborator process
```
some (0 - Format.getIndent (← getOptions))
```
with expected type `(Option Int)`. So, the `-` is interpreted as
`Int.sub` although `Format.getIndent (← getOptions)` has type `Nat`.
In the new `HSub`, the expected type doesn't really influence TC
resolution since it is an `outparam`. So, we failed with the error
failed to synthesize `HSub Nat Nat Int`.
One possible fix was to add the instance `HSub Nat Nat Int` with
`Int.sub`, but I used the following fix
```
some ((0 : Int) - Format.getIndent (← getOptions))
```
which makes it clear that we want the `Int.sub` operator instead of
`Nat.sub`.
2020-12-01 14:02:46 -08:00

283 lines
12 KiB
Text
Raw Blame History

/-
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.Fin.Basic
import Init.System.Platform
open Nat
@[extern "lean_uint8_of_nat"]
def UInt8.ofNat (n : @& Nat) : UInt8 := ⟨Fin.ofNat n⟩
abbrev Nat.toUInt8 := UInt8.ofNat
@[extern "lean_uint8_to_nat"]
def UInt8.toNat (n : UInt8) : Nat := n.val.val
@[extern c inline "#1 + #2"]
def UInt8.add (a b : UInt8) : UInt8 := ⟨a.val + b.val⟩
@[extern c inline "#1 - #2"]
def UInt8.sub (a b : UInt8) : UInt8 := ⟨a.val - b.val⟩
@[extern c inline "#1 * #2"]
def UInt8.mul (a b : UInt8) : UInt8 := ⟨a.val * b.val⟩
@[extern c inline "#2 == 0 ? 0 : #1 / #2"]
def UInt8.div (a b : UInt8) : UInt8 := ⟨a.val / b.val⟩
@[extern c inline "#2 == 0 ? 0 : #1 % #2"]
def UInt8.mod (a b : UInt8) : UInt8 := ⟨a.val % b.val⟩
@[extern "lean_uint8_modn"]
def UInt8.modn (a : UInt8) (n : @& Nat) : UInt8 := ⟨a.val % n⟩
@[extern c inline "#1 & #2"]
def UInt8.land (a b : UInt8) : UInt8 := ⟨Fin.land a.val b.val⟩
@[extern c inline "#1 | #2"]
def UInt8.lor (a b : UInt8) : UInt8 := ⟨Fin.lor a.val b.val⟩
def UInt8.lt (a b : UInt8) : Prop := a.val < b.val
def UInt8.le (a b : UInt8) : Prop := a.val ≤ b.val
instance : OfNat UInt8 n := ⟨UInt8.ofNat n⟩
instance : Add UInt8 := ⟨UInt8.add⟩
instance : Sub UInt8 := ⟨UInt8.sub⟩
instance : Mul UInt8 := ⟨UInt8.mul⟩
instance : Mod UInt8 := ⟨UInt8.mod⟩
instance : HMod UInt8 Nat UInt8 := ⟨UInt8.modn⟩
instance : Div UInt8 := ⟨UInt8.div⟩
instance : HasLess UInt8 := ⟨UInt8.lt⟩
instance : HasLessEq UInt8 := ⟨UInt8.le⟩
set_option bootstrap.gen_matcher_code false in
@[extern c inline "#1 < #2"]
def UInt8.decLt (a b : UInt8) : Decidable (a < b) :=
match a, b with
| ⟨n⟩, ⟨m⟩ => inferInstanceAs (Decidable (n < m))
set_option bootstrap.gen_matcher_code false in
@[extern c inline "#1 <= #2"]
def UInt8.decLe (a b : UInt8) : Decidable (a ≤ b) :=
match a, b with
| ⟨n⟩, ⟨m⟩ => inferInstanceAs (Decidable (n <= m))
instance (a b : UInt8) : Decidable (a < b) := UInt8.decLt a b
instance (a b : UInt8) : Decidable (a ≤ b) := UInt8.decLe a b
@[extern "lean_uint16_of_nat"]
def UInt16.ofNat (n : @& Nat) : UInt16 := ⟨Fin.ofNat n⟩
abbrev Nat.toUInt16 := UInt16.ofNat
@[extern "lean_uint16_to_nat"]
def UInt16.toNat (n : UInt16) : Nat := n.val.val
@[extern c inline "#1 + #2"]
def UInt16.add (a b : UInt16) : UInt16 := ⟨a.val + b.val⟩
@[extern c inline "#1 - #2"]
def UInt16.sub (a b : UInt16) : UInt16 := ⟨a.val - b.val⟩
@[extern c inline "#1 * #2"]
def UInt16.mul (a b : UInt16) : UInt16 := ⟨a.val * b.val⟩
@[extern c inline "#2 == 0 ? 0 : #1 / #2"]
def UInt16.div (a b : UInt16) : UInt16 := ⟨a.val / b.val⟩
@[extern c inline "#2 == 0 ? 0 : #1 % #2"]
def UInt16.mod (a b : UInt16) : UInt16 := ⟨a.val % b.val⟩
@[extern "lean_uint16_modn"]
def UInt16.modn (a : UInt16) (n : @& Nat) : UInt16 := ⟨a.val % n⟩
@[extern c inline "#1 & #2"]
def UInt16.land (a b : UInt16) : UInt16 := ⟨Fin.land a.val b.val⟩
@[extern c inline "#1 | #2"]
def UInt16.lor (a b : UInt16) : UInt16 := ⟨Fin.lor a.val b.val⟩
def UInt16.lt (a b : UInt16) : Prop := a.val < b.val
def UInt16.le (a b : UInt16) : Prop := a.val ≤ b.val
instance : OfNat UInt16 n := ⟨UInt16.ofNat n⟩
instance : Add UInt16 := ⟨UInt16.add⟩
instance : Sub UInt16 := ⟨UInt16.sub⟩
instance : Mul UInt16 := ⟨UInt16.mul⟩
instance : Mod UInt16 := ⟨UInt16.mod⟩
instance : HMod UInt16 Nat UInt16 := ⟨UInt16.modn⟩
instance : Div UInt16 := ⟨UInt16.div⟩
instance : HasLess UInt16 := ⟨UInt16.lt⟩
instance : HasLessEq UInt16 := ⟨UInt16.le⟩
set_option bootstrap.gen_matcher_code false in
@[extern c inline "#1 < #2"]
def UInt16.decLt (a b : UInt16) : Decidable (a < b) :=
match a, b with
| ⟨n⟩, ⟨m⟩ => inferInstanceAs (Decidable (n < m))
set_option bootstrap.gen_matcher_code false in
@[extern c inline "#1 <= #2"]
def UInt16.decLe (a b : UInt16) : Decidable (a ≤ b) :=
match a, b with
| ⟨n⟩, ⟨m⟩ => inferInstanceAs (Decidable (n <= m))
instance (a b : UInt16) : Decidable (a < b) := UInt16.decLt a b
instance (a b : UInt16) : Decidable (a ≤ b) := UInt16.decLe a b
@[extern "lean_uint32_of_nat"]
def UInt32.ofNat (n : @& Nat) : UInt32 := ⟨Fin.ofNat n⟩
@[extern "lean_uint32_of_nat"]
def UInt32.ofNat' (n : Nat) (h : n < UInt32.size) : UInt32 := ⟨⟨n, h⟩⟩
abbrev Nat.toUInt32 := UInt32.ofNat
@[extern c inline "#1 + #2"]
def UInt32.add (a b : UInt32) : UInt32 := ⟨a.val + b.val⟩
@[extern c inline "#1 - #2"]
def UInt32.sub (a b : UInt32) : UInt32 := ⟨a.val - b.val⟩
@[extern c inline "#1 * #2"]
def UInt32.mul (a b : UInt32) : UInt32 := ⟨a.val * b.val⟩
@[extern c inline "#2 == 0 ? 0 : #1 / #2"]
def UInt32.div (a b : UInt32) : UInt32 := ⟨a.val / b.val⟩
@[extern c inline "#2 == 0 ? 0 : #1 % #2"]
def UInt32.mod (a b : UInt32) : UInt32 := ⟨a.val % b.val⟩
@[extern "lean_uint32_modn"]
def UInt32.modn (a : UInt32) (n : @& Nat) : UInt32 := ⟨a.val % n⟩
@[extern c inline "#1 & #2"]
def UInt32.land (a b : UInt32) : UInt32 := ⟨Fin.land a.val b.val⟩
@[extern c inline "#1 | #2"]
def UInt32.lor (a b : UInt32) : UInt32 := ⟨Fin.lor a.val b.val⟩
@[extern c inline "((uint8_t)#1)"]
def UInt32.toUInt8 (a : UInt32) : UInt8 := a.toNat.toUInt8
@[extern c inline "((uint16_t)#1)"]
def UInt32.toUInt16 (a : UInt32) : UInt16 := a.toNat.toUInt16
@[extern c inline "((uint32_t)#1)"]
def UInt8.toUInt32 (a : UInt8) : UInt32 := a.toNat.toUInt32
instance : OfNat UInt32 n := ⟨UInt32.ofNat n⟩
instance : Add UInt32 := ⟨UInt32.add⟩
instance : Sub UInt32 := ⟨UInt32.sub⟩
instance : Mul UInt32 := ⟨UInt32.mul⟩
instance : Mod UInt32 := ⟨UInt32.mod⟩
instance : HMod UInt32 Nat UInt32 := ⟨UInt32.modn⟩
instance : Div UInt32 := ⟨UInt32.div⟩
@[extern c inline "#1 << #2"]
constant UInt32.shiftLeft (a b : UInt32) : UInt32
@[extern c inline "#1 >> #2"]
constant UInt32.shiftRight (a b : UInt32) : UInt32
@[extern "lean_uint64_of_nat"]
def UInt64.ofNat (n : @& Nat) : UInt64 := ⟨Fin.ofNat n⟩
abbrev Nat.toUInt64 := UInt64.ofNat
@[extern "lean_uint64_to_nat"]
def UInt64.toNat (n : UInt64) : Nat := n.val.val
@[extern c inline "#1 + #2"]
def UInt64.add (a b : UInt64) : UInt64 := ⟨a.val + b.val⟩
@[extern c inline "#1 - #2"]
def UInt64.sub (a b : UInt64) : UInt64 := ⟨a.val - b.val⟩
@[extern c inline "#1 * #2"]
def UInt64.mul (a b : UInt64) : UInt64 := ⟨a.val * b.val⟩
@[extern c inline "#2 == 0 ? 0 : #1 / #2"]
def UInt64.div (a b : UInt64) : UInt64 := ⟨a.val / b.val⟩
@[extern c inline "#2 == 0 ? 0 : #1 % #2"]
def UInt64.mod (a b : UInt64) : UInt64 := ⟨a.val % b.val⟩
@[extern "lean_uint64_modn"]
def UInt64.modn (a : UInt64) (n : @& Nat) : UInt64 := ⟨a.val % n⟩
@[extern c inline "#1 & #2"]
def UInt64.land (a b : UInt64) : UInt64 := ⟨Fin.land a.val b.val⟩
@[extern c inline "#1 | #2"]
def UInt64.lor (a b : UInt64) : UInt64 := ⟨Fin.lor a.val b.val⟩
def UInt64.lt (a b : UInt64) : Prop := a.val < b.val
def UInt64.le (a b : UInt64) : Prop := a.val ≤ b.val
@[extern c inline "((uint8_t)#1)"]
def UInt64.toUInt8 (a : UInt64) : UInt8 := a.toNat.toUInt8
@[extern c inline "((uint16_t)#1)"]
def UInt64.toUInt16 (a : UInt64) : UInt16 := a.toNat.toUInt16
@[extern c inline "((uint32_t)#1)"]
def UInt64.toUInt32 (a : UInt64) : UInt32 := a.toNat.toUInt32
@[extern c inline "((uint64_t)#1)"]
def UInt32.toUInt64 (a : UInt32) : UInt64 := a.toNat.toUInt64
-- TODO(Leo): give reference implementation for shiftLeft and shiftRight, and define them for other UInt types
@[extern c inline "#1 << #2"]
constant UInt64.shiftLeft (a b : UInt64) : UInt64
@[extern c inline "#1 >> #2"]
constant UInt64.shiftRight (a b : UInt64) : UInt64
instance : OfNat UInt64 n := ⟨UInt64.ofNat n⟩
instance : Add UInt64 := ⟨UInt64.add⟩
instance : Sub UInt64 := ⟨UInt64.sub⟩
instance : Mul UInt64 := ⟨UInt64.mul⟩
instance : Mod UInt64 := ⟨UInt64.mod⟩
instance : HMod UInt64 Nat UInt64 := ⟨UInt64.modn⟩
instance : Div UInt64 := ⟨UInt64.div⟩
instance : HasLess UInt64 := ⟨UInt64.lt⟩
instance : HasLessEq UInt64 := ⟨UInt64.le⟩
@[extern c inline "(uint64_t)#1"]
def Bool.toUInt64 (b : Bool) : UInt64 := if b then 1 else 0
set_option bootstrap.gen_matcher_code false in
@[extern c inline "#1 < #2"]
def UInt64.decLt (a b : UInt64) : Decidable (a < b) :=
match a, b with
| ⟨n⟩, ⟨m⟩ => inferInstanceAs (Decidable (n < m))
set_option bootstrap.gen_matcher_code false in
@[extern c inline "#1 <= #2"]
def UInt64.decLe (a b : UInt64) : Decidable (a ≤ b) :=
match a, b with
| ⟨n⟩, ⟨m⟩ => inferInstanceAs (Decidable (n <= m))
instance (a b : UInt64) : Decidable (a < b) := UInt64.decLt a b
instance (a b : UInt64) : Decidable (a ≤ b) := UInt64.decLe a b
theorem usizeSzGt0 : USize.size > 0 :=
Nat.posPowOfPos System.Platform.numBits (Nat.zeroLtSucc _)
@[extern "lean_usize_of_nat"]
def USize.ofNat (n : @& Nat) : USize := ⟨Fin.ofNat' n usizeSzGt0⟩
abbrev Nat.toUSize := USize.ofNat
@[extern "lean_usize_to_nat"]
def USize.toNat (n : USize) : Nat := n.val.val
@[extern c inline "#1 + #2"]
def USize.add (a b : USize) : USize := ⟨a.val + b.val⟩
@[extern c inline "#1 - #2"]
def USize.sub (a b : USize) : USize := ⟨a.val - b.val⟩
@[extern c inline "#1 * #2"]
def USize.mul (a b : USize) : USize := ⟨a.val * b.val⟩
@[extern c inline "#2 == 0 ? 0 : #1 / #2"]
def USize.div (a b : USize) : USize := ⟨a.val / b.val⟩
@[extern c inline "#2 == 0 ? 0 : #1 % #2"]
def USize.mod (a b : USize) : USize := ⟨a.val % b.val⟩
@[extern "lean_usize_modn"]
def USize.modn (a : USize) (n : @& Nat) : USize := ⟨a.val % n⟩
@[extern c inline "#1 & #2"]
def USize.land (a b : USize) : USize := ⟨Fin.land a.val b.val⟩
@[extern c inline "#1 | #2"]
def USize.lor (a b : USize) : USize := ⟨Fin.lor a.val b.val⟩
@[extern c inline "#1"]
def UInt32.toUSize (a : UInt32) : USize := a.toNat.toUSize
@[extern c inline "((size_t)#1)"]
def UInt64.toUSize (a : UInt64) : USize := a.toNat.toUSize
@[extern c inline "(uint32_t)#1"]
def USize.toUInt32 (a : USize) : UInt32 := a.toNat.toUInt32
-- TODO(Leo): give reference implementation for shiftLeft and shiftRight, and define them for other UInt types
@[extern c inline "#1 << #2"]
constant USize.shiftLeft (a b : USize) : USize
@[extern c inline "#1 >> #2"]
constant USize.shiftRight (a b : USize) : USize
def USize.lt (a b : USize) : Prop := a.val < b.val
def USize.le (a b : USize) : Prop := a.val ≤ b.val
instance : OfNat USize n := ⟨USize.ofNat n⟩
instance : Add USize := ⟨USize.add⟩
instance : Sub USize := ⟨USize.sub⟩
instance : Mul USize := ⟨USize.mul⟩
instance : Mod USize := ⟨USize.mod⟩
instance : HMod USize Nat USize := ⟨USize.modn⟩
instance : Div USize := ⟨USize.div⟩
instance : HasLess USize := ⟨USize.lt⟩
instance : HasLessEq USize := ⟨USize.le⟩
set_option bootstrap.gen_matcher_code false in
@[extern c inline "#1 < #2"]
def USize.decLt (a b : USize) : Decidable (a < b) :=
match a, b with
| ⟨n⟩, ⟨m⟩ => inferInstanceAs (Decidable (n < m))
set_option bootstrap.gen_matcher_code false in
@[extern c inline "#1 <= #2"]
def USize.decLe (a b : USize) : Decidable (a ≤ b) :=
match a, b with
| ⟨n⟩, ⟨m⟩ => inferInstanceAs (Decidable (n <= m))
instance (a b : USize) : Decidable (a < b) := USize.decLt a b
instance (a b : USize) : Decidable (a ≤ b) := USize.decLe a b
theorem USize.modnLt {m : Nat} : ∀ (u : USize), m > 0 → USize.toNat (u % m) < m
| ⟨u⟩, h => Fin.modnLt u h
Reference in a new issue View git blame Copy permalink