Refactor to hopefully avoid compiler bugs

mem/decode.ml

@@ -0,0 +1,5 @@
+open import "prelude.ml"
+
+class decode 'a begin
+  val decode : int -> 'a
+end

mem/int.ml

@@ -0,0 +1,77 @@
+open import "prelude.ml"
+open import "./decode.ml"
+open import "../dolphin.ml"
+
+type u8 =
+  U8 of int
+
+instance show u8 begin
+  let show (U8 x) = (show x) ^ "_u8"
+end
+
+instance decode u8 begin
+  let decode addr = U8 (Dolphin.read_value_8 addr)
+end
+
+type s8 =
+  S8 of int
+
+instance show s8 begin
+  let show (S8 x) = (show x) ^ "_s8"
+end
+
+instance decode s8 begin
+  let decode addr =
+    let u8 = Dolphin.read_value_8 addr
+    let signfix =
+      if u8 > 127 then
+        negate (256 - u8)
+      else
+        u8
+    S8 signfix
+end
+
+type u16 =
+  U16 of int
+
+instance show u16 begin
+  let show (U16 x) = (show x) ^ "_u16"
+end
+
+type s16 =
+  S16 of int
+
+instance show s16 begin
+  let show (S16 x) = (show x) ^ "_s16"
+end
+
+instance decode s16 begin
+  let decode addr =
+    let u16 = Dolphin.read_value_16 addr
+    let signfix =
+      if u16 > 32767 then
+        negate (65536 - u16)
+      else
+        u16
+    S16 signfix
+end
+
+type u32 =
+  U32 of int
+
+instance show u32 begin
+  let show (U32 x) = (show x) ^ "_u32"
+end
+
+type s32 =
+  S32 of int
+
+instance show s32 begin
+  let show (S32 x) =
+    let signfix =
+      if x > 2147483647 then
+        negate (4294967296 - x)
+      else
+        x
+  (show signfix) ^ "_s32"
+end