Optimize addition and subtraction at comptime too

lib/orb/i32/dsl.ex

@@ -19,7 +19,6 @@ defmodule Orb.I32.DSL do
 
   def left * right do
     Orb.Numeric.Multiply.optimized(Orb.I32, left, right)
-    # Orb.I32.mul(left, right)
   end
 
   def _left == _right do

lib/orb/numeric/add.ex

@@ -9,6 +9,9 @@ defmodule Orb.Numeric.Add do
   [MDN reference](https://developer.mozilla.org/en-US/docs/WebAssembly/Reference/Numeric/Addition)
   """
 
+  # Perform at comptime.
+  def optimized(_type, a, b) when is_integer(a) and is_integer(b), do: a + b
+  # Add anything by zero is that same thing.
   def optimized(_type, a, 0), do: a
   def optimized(_type, 0, b), do: b
   # def optimized(type, a, b), do: {type.wasm_type(), :add, {a, b}}

lib/orb/numeric/multiply.ex

@@ -17,6 +17,6 @@ defmodule Orb.Numeric.Multiply do
   # Multiply anything by one is that same thing.
   def optimized(_type, a, 1), do: a
   def optimized(_type, 1, b), do: b
-  # Finally, spit out the instruction.
+  # Finally, spit out the runtime instruction.
   def optimized(type, a, b), do: Orb.Instruction.new(type.wasm_type(), :mul, [a, b])
 end

lib/orb/numeric/sub.ex

@@ -9,6 +9,9 @@ defmodule Orb.Numeric.Subtract do
   [MDN reference](https://developer.mozilla.org/en-US/docs/WebAssembly/Reference/Numeric/Subtraction)
   """
 
+  # Perform at comptime.
+  def optimized(_type, a, b) when is_integer(a) and is_integer(b), do: a - b
+  # Minus zero from anything is that same thing.
   def optimized(_type, a, 0), do: a
   def optimized(type, a, b), do: Orb.Instruction.new(type.wasm_type(), :sub, [a, b])
 end

test/examples/arena.exs

@@ -12,10 +12,18 @@ defmodule Examples.Arena do
 
     Orb.snippet Orb.S32, new_ptr: I32.UnsafePointer do
       new_ptr = Instruction.global_get(Orb.I32, offset_global_name)
+
+
+
+
       if new_ptr + byte_count > end_offset * Orb.Memory.page_byte_size() do
         unreachable!()
       end
 
+
+
+
+
       Instruction.global_set(Orb.I32, offset_global_name, new_ptr + byte_count)
 
       new_ptr

test/operators_test.exs

@@ -8,8 +8,12 @@ defmodule OperatorsTest do
       use Orb
 
       wasm do
-        func add(), I32 do
+        func add(a: I32) do
           1 + 2
+          :drop
+
+          a + 2
+          :drop
         end
 
         func multiply(a: I32, b: I32) do
@@ -48,8 +52,11 @@ defmodule OperatorsTest do
 
     assert to_wat(D1) == """
            (module $D1
-             (func $add (export "add") (result i32)
-               (i32.add (i32.const 1) (i32.const 2))
+             (func $add (export "add") (param $a i32)
+               (i32.const 3)
+               drop
+               (i32.add (local.get $a) (i32.const 2))
+               drop
              )
              (func $multiply (export "multiply") (param $a i32) (param $b i32)
                (i32.mul (local.get $a) (local.get $b))
@@ -83,8 +90,12 @@ defmodule OperatorsTest do
       use Orb
 
       wasm U32 do
-        func add(), I32 do
+        func add(a: I32) do
           1 + 2
+          :drop
+
+          a + 2
+          :drop
         end
 
         func multiply(a: I32, b: I32) do
@@ -118,8 +129,11 @@ defmodule OperatorsTest do
 
     assert to_wat(U1) == """
            (module $U1
-             (func $add (export "add") (result i32)
-               (i32.add (i32.const 1) (i32.const 2))
+             (func $add (export "add") (param $a i32)
+               (i32.const 3)
+               drop
+               (i32.add (local.get $a) (i32.const 2))
+               drop
              )
              (func $multiply (export "multiply") (param $a i32) (param $b i32)
                (i32.mul (local.get $a) (local.get $b))

test/orb_test.exs

@@ -802,7 +802,7 @@ defmodule OrbTest do
     (module $SnippetUser
       (memory (export "memory") 1)
       (func $answer (export "answer") (result i32)
-        (i32.load (i32.add (i32.const #{0x100}) (i32.const 4)))
+        (i32.load (i32.const #{0x104}))
       )
     )
     """