globals

src/ast.ts

@@ -81,6 +81,9 @@ export class ItemId {
   }
 
   toString(): string {
+    if (this.crateId === 0) {
+      return `${this.itemIdx}`;
+    }
     return `[${this.crateId}@${this.itemIdx}]`;
   }
 }
@@ -105,6 +108,10 @@ export type ItemKind<P extends Phase> =
   | {
       kind: "extern";
       node: ExternItem;
+    }
+  | {
+      kind: "global";
+      node: GlobalItem<P>;
     };
 
 export type Item<P extends Phase> = ItemKind<P> & {
@@ -153,6 +160,13 @@ export type ModItem<P extends Phase> = {
 
 export type ExternItem = { name: string };
 
+export type GlobalItem<P extends Phase> = {
+  name: string;
+  type: Type<P>;
+  init: Expr<P>;
+  ty?: Ty;
+};
+
 export type ExprEmpty = { kind: "empty" };
 
 export type ExprLet<P extends Phase> = {
@@ -634,6 +648,17 @@ export function superFoldItem<From extends Phase, To extends Phase>(
     case "extern": {
       return { ...item, kind: "extern" };
     }
+    case "global": {
+      return {
+        ...item,
+        kind: "global",
+        node: {
+          name: item.node.name,
+          type: folder.type(item.node.type),
+          init: folder.expr(item.node.init),
+        },
+      };
+    }
   }
 }
 

src/index.ts

@@ -13,10 +13,10 @@ import { Crate, Built, Typecked } from "./ast";
 import { Ids } from "./utils";
 
 const INPUT = `
-extern mod std;
+global HELLO: I32 = 0_I32;
 
 function main() = (
-  std.printlnInt(10000);
+  HELLO = 1_I32;
 ); 
 `;
 

src/lexer.ts

@@ -12,6 +12,7 @@ export type DatalessToken =
   | "import"
   | "extern"
   | "mod"
+  | "global"
   | "("
   | ")"
   | "{"
@@ -316,6 +317,7 @@ const KEYOWRDS: DatalessToken[] = [
   "import",
   "extern",
   "mod",
+  "global",
 ];
 
 const KEYWORD_SET = new Set<string>(KEYOWRDS);

src/lower.ts

@@ -3,8 +3,10 @@ import {
   Expr,
   ExprBlock,
   FunctionDef,
+  GlobalItem,
   ImportDef,
   Item,
+  ItemId,
   LoopId,
   Resolution,
   Ty,
@@ -13,6 +15,7 @@ import {
   Typecked,
   varUnreachable,
 } from "./ast";
+import { printTy } from "./printer";
 import { ComplexMap, encodeUtf8, unwrap } from "./utils";
 import * as wasm from "./wasm/defs";
 
@@ -25,10 +28,19 @@ const STRING_ABI: ArgRetAbi = STRING_TYPES;
 
 const WASM_PAGE = 65536;
 
-type Relocation = {
+const DUMMY_IDX = 9999999;
-  kind: "funccall";
+
-  instr: wasm.Instr & { func: wasm.FuncIdx };
+type RelocationKind =
-} & { res: Resolution };
+  | {
+      kind: "funccall";
+      instr: wasm.Instr & { func: wasm.FuncIdx };
+    }
+  | {
+      kind: "globalref";
+      instr: wasm.Instr & { imm: wasm.GlobalIdx };
+    };
+
+type Relocation = RelocationKind & { res: Resolution };
 
 type FuncOrImport =
   | { kind: "func"; idx: wasm.FuncIdx }
@@ -39,6 +51,7 @@ export type Context = {
   funcTypes: ComplexMap<wasm.FuncType, wasm.TypeIdx>;
   reservedHeapMemoryStart: number;
   funcIndices: ComplexMap<Resolution, FuncOrImport>;
+  globalIndices: ComplexMap<Resolution, wasm.GlobalIdx>;
   crates: Crate<Typecked>[];
   relocations: Relocation[];
 };
@@ -89,6 +102,12 @@ function appendData(cx: Context, newData: Uint8Array): number {
   }
 }
 
+function findItem(cx: Context, id: ItemId): Item<Typecked> {
+  return unwrap(
+    unwrap(cx.crates.find((crate) => crate.id === id.crateId)).itemsById.get(id)
+  );
+}
+
 export function lower(crates: Crate<Typecked>[]): wasm.Module {
   const mod: wasm.Module = {
     types: [],
@@ -118,6 +137,7 @@ export function lower(crates: Crate<Typecked>[]): wasm.Module {
     mod,
     funcTypes: new ComplexMap(),
     funcIndices: new ComplexMap(),
+    globalIndices: new ComplexMap(),
     reservedHeapMemoryStart: 0,
     crates,
     relocations: [],
@@ -136,6 +156,17 @@ export function lower(crates: Crate<Typecked>[]): wasm.Module {
         }
         case "mod": {
           lowerMod(item.node.contents);
+          break;
+        }
+        case "global": {
+          lowerGlobal(cx, item, item.node);
+          break;
+        }
+        case "extern":
+        case "type":
+          break;
+        default: {
+          const _: never = item;
         }
       }
     });
@@ -162,6 +193,20 @@ export function lower(crates: Crate<Typecked>[]): wasm.Module {
           );
         }
         rel.instr.func = idx.kind === "func" ? offset + idx.idx : idx.idx;
+        break;
+      }
+      case "globalref": {
+        const idx = cx.globalIndices.get(rel.res);
+        if (idx === undefined) {
+          throw new Error(
+            `no global found for relocation '${JSON.stringify(rel.res)}'`
+          );
+        }
+        rel.instr.imm = idx;
+        break;
+      }
+      default: {
+        const _: never = rel;
       }
     }
   });
@@ -201,6 +246,43 @@ function lowerImport(
   cx.funcIndices.set({ kind: "item", id: item.id }, { kind: "import", idx });
 }
 
+function lowerGlobal(
+  cx: Context,
+  item: Item<Typecked>,
+  def: GlobalItem<Typecked>
+) {
+  const globalIdx = cx.mod.globals.length;
+
+  let valtype: "i32" | "i64";
+  switch (def.init.ty.kind) {
+    case "i32":
+      valtype = "i32";
+      break;
+    case "int":
+      valtype = "i64";
+      break;
+    default:
+      throw new Error(`invalid global ty: ${printTy(def.init.ty)}`);
+  }
+
+  if (def.init.kind !== "literal" || def.init.value.kind !== "int") {
+    throw new Error(`invalid global init: ${JSON.stringify(def)}`);
+  }
+
+  const init: wasm.Instr = {
+    kind: `${valtype}.const`,
+    imm: def.init.value.value,
+  };
+
+  cx.mod.globals.push({
+    _name: mangleDefPath(item.defPath),
+    type: { type: valtype, mut: "var" },
+    init: [init],
+  });
+
+  cx.globalIndices.set({ kind: "item", id: item.id }, globalIdx);
+}
+
 type FuncContext = {
   cx: Context;
   item: Item<Typecked>;
@@ -304,7 +386,18 @@ function lowerExpr(
               break;
             }
             case "item": {
-              throw new Error("cannot store to item");
+              const item = findItem(fcx.cx, res.id);
+              if (item.kind !== "global") {
+                throw new Error("cannot store to non-global item");
+              }
+
+              const instr: wasm.Instr = { kind: "global.set", imm: DUMMY_IDX };
+              const rel: Relocation = { kind: "globalref", instr, res };
+
+              fcx.cx.relocations.push(rel);
+              instrs.push(instr);
+
+              break;
             }
             case "builtin": {
               throw new Error("cannot store to builtin");
@@ -374,8 +467,23 @@ function lowerExpr(
           loadVariable(instrs, location);
           break;
         }
-        case "item":
+        case "item": {
-          todo("item ident res");
+          const item = findItem(fcx.cx, res.id);
+          switch (item.kind) {
+            case "global": {
+              const instr: wasm.Instr = { kind: "global.get", imm: DUMMY_IDX };
+              const rel: Relocation = { kind: "globalref", instr, res };
+              instrs.push(instr);
+              fcx.cx.relocations.push(rel);
+              break;
+            }
+            default: {
+              todo("non-global item ident res");
+            }
+          }
+
+          break;
+        }
         case "builtin":
           switch (res.name) {
             case "false":
@@ -561,7 +669,7 @@ function lowerExpr(
         }
       }
 
-      const callInstr: wasm.Instr = { kind: "call", func: 9999999999 };
+      const callInstr: wasm.Instr = { kind: "call", func: DUMMY_IDX };
       fcx.cx.relocations.push({
         kind: "funccall",
         instr: callInstr,
@@ -865,7 +973,7 @@ function addRt(cx: Context, crates: Crate<Typecked>[]) {
 
   const crate0 = unwrap(crates.find((crate) => crate.id === 0));
 
-  const mainCall: wasm.Instr = { kind: "call", func: 9999999 };
+  const mainCall: wasm.Instr = { kind: "call", func: DUMMY_IDX };
   cx.relocations.push({
     kind: "funccall",
     instr: mainCall,

src/parser.ts

@@ -29,6 +29,7 @@ import {
   Parsed,
   ExternItem,
   ItemId,
+  GlobalItem,
 } from "./ast";
 import { CompilerError, Span, spanMerge } from "./error";
 import { BaseToken, Token, TokenIdent, TokenLitString } from "./lexer";
@@ -180,6 +181,24 @@ function parseItem(t: Token[]): [Token[], Item<Parsed>] {
     };
 
     return [t, { kind: "mod", node, span: name.span, id: ItemId.dummy() }];
+  } else if (tok.kind === "global") {
+    let name;
+    [t, name] = expectNext<TokenIdent>(t, "identifier");
+    [t] = expectNext(t, ":");
+    let type;
+    [t, type] = parseType(t);
+    [t] = expectNext(t, "=");
+    let init;
+    [t, init] = parseExpr(t);
+    [t] = expectNext(t, ";");
+
+    const node: GlobalItem<Parsed> = {
+      name: name.ident,
+      type,
+      init,
+    };
+
+    return [t, { kind: "global", node, span: name.span, id: ItemId.dummy() }];
   } else {
     unexpectedToken(tok, "item");
   }

src/printer.ts

@@ -24,7 +24,7 @@ function printStringLiteral(lit: StringLiteral): string {
 }
 
 function printItem(item: Item<AnyPhase>): string {
-  const id = `/*${item.id}*/ `;
+  const id = `/*${item.id.toString()}*/ `;
 
   switch (item.kind) {
     case "function": {
@@ -42,6 +42,15 @@ function printItem(item: Item<AnyPhase>): string {
     case "extern": {
       return id + `extern mod ${item.node.name};`;
     }
+    case "global": {
+      return (
+        id +
+        `global ${item.node.name}: ${printType(item.node.type)} = ${printExpr(
+          item.node.init,
+          0
+        )};`
+      );
+    }
   }
 }
 
@@ -207,7 +216,7 @@ function printRes(res: Resolution): string {
     case "local":
       return `#${res.index}`;
     case "item":
-      return `#G${res.id}`;
+      return `#I${res.id.toString()}`;
     case "builtin": {
       return `#B`;
     }

src/typeck.ts

@@ -120,6 +120,7 @@ export function typeck(
   otherCrates: Crate<Typecked>[]
 ): Crate<Typecked> {
   const itemTys = new ComplexMap<ItemId, Ty | null>();
+
   function typeOfItem(itemId: ItemId, cause: Span): Ty {
     if (itemId.crateId !== ast.id) {
       console.log(otherCrates);
@@ -132,6 +133,7 @@ export function typeck(
         case "function":
         case "import":
         case "type":
+        case "global":
           return item.node.ty!;
         case "mod": {
           throw new CompilerError(
@@ -203,6 +205,11 @@ export function typeck(
           cause
         );
       }
+      case "global": {
+        const ty = lowerAstTy(item.node.type);
+        itemTys.set(item.id, ty);
+        return ty;
+      }
     }
   }
 
@@ -227,13 +234,24 @@ export function typeck(
     );
   }
 
+  function findItem(itemId: ItemId): Item<Resolved> {
+    if (itemId.crateId === ast.id) {
+      return unwrap(ast.itemsById.get(itemId));
+    }
+    return unwrap(
+      unwrap(
+        otherCrates.find((crate) => crate.id === itemId.crateId)
+      ).itemsById.get(itemId)
+    );
+  }
+
   const checker: Folder<Resolved, Typecked> = {
     ...mkDefaultFolder(),
     itemInner(item: Item<Resolved>): Item<Typecked> {
       switch (item.kind) {
         case "function": {
           const fnTy = typeOfItem(item.id, item.span) as TyFn;
-          const body = checkBody(item.node.body, fnTy, typeOfItem);
+          const body = checkBody(item.node.body, fnTy, typeOfItem, findItem);
 
           const returnType = item.node.returnType && {
             ...item.node.returnType,
@@ -349,6 +367,30 @@ export function typeck(
             node: { ...item.node },
           };
         }
+        case "global": {
+          const ty = typeOfItem(item.id, item.span);
+          const { init } = item.node;
+
+          if (init.kind !== "literal" || init.value.kind !== "int") {
+            throw new CompilerError(
+              "globals must be initialized with an integer literal",
+              init.span
+            );
+          }
+
+          const initTy = init.value.type === "I32" ? TY_I32 : TY_INT;
+          const infcx = new InferContext();
+          infcx.assign(ty, initTy, init.span);
+
+          return {
+            ...item,
+            node: {
+              ...item.node,
+              ty,
+              init: { ...init, ty },
+            },
+          };
+        }
       }
     },
     expr(_expr) {
@@ -560,7 +602,8 @@ export class InferContext {
 export function checkBody(
   body: Expr<Resolved>,
   fnTy: TyFn,
-  typeOfItem: (itemId: ItemId, cause: Span) => Ty
+  typeOfItem: (itemId: ItemId, cause: Span) => Ty,
+  findItem: (itemId: ItemId) => Item<Resolved>
 ): Expr<Typecked> {
   const localTys = [...fnTy.params];
   const loopState: { hasBreak: boolean; loopId: LoopId }[] = [];
@@ -644,11 +687,26 @@ export function checkBody(
           infcx.assign(lhs.ty, rhs.ty, expr.span);
 
           switch (lhs.kind) {
-            case "ident":
+            case "ident": {
-              if (lhs.value.res.kind !== "local") {
+              const { res } = lhs.value;
-                throw new CompilerError("cannot assign to items", expr.span);
+              switch (res.kind) {
+                case "local":
+                  break;
+                case "item": {
+                  const item = findItem(res.id);
+                  if (item.kind !== "global") {
+                    throw new CompilerError("cannot assign to item", expr.span);
+                  }
+                  break;
+                }
+                case "builtin":
+                  throw new CompilerError(
+                    "cannot assign to builtins",
+                    expr.span
+                  );
               }
               break;
+            }
             default: {
               throw new CompilerError(
                 "invalid left-hand side of assignment",

std.nil

@@ -57,3 +57,9 @@ function println(s: String) = (
   print(s);
   print("\n");
 );
+
+mod alloc (
+    function allocateItem(size: I32): I32 = (
+        
+    );
+)

test.nil

@@ -1,69 +1,5 @@
-mod owo ();
+extern mod std;
 
 function main() = (
-  prIntln(0);
+  std.printInt(10);
-  prIntln(1);
+);
-  prIntln(9);
-  prIntln(2352353);
-  prIntln(100);
-);
-
-function prIntln(x: Int) = (
-  prInt(x);
-  print("\n");
-);
-
-function stringForDigit(x: Int): String = 
-  if x == 0 then "0"
-  else if x == 1 then "1"
-  else if x == 2 then "2"
-  else if x == 3 then "3"
-  else if x == 4 then "4"
-  else if x == 5 then "5"
-  else if x == 6 then "6"
-  else if x == 7 then "7"
-  else if x == 8 then "8"
-  else if x == 9 then "9"
-  else trap();
-
-function log10(x: Int): Int = (
-  let i = 0;
-  loop (
-    if x < 10 then break;
-    i = i + 1;
-    x = x / 10;
-  );
-  i
-);
-
-function pow(base: Int, exp: Int): Int = (
-  let acc = 1;
-  loop (
-    if exp == 0 then break;
-    acc = acc * base;
-    exp = exp - 1;
-  );
-  acc
-);
-
-function prInt(x: Int) = (
-  let mag = log10(x);
-
-  loop (
-    if mag == 0 then break;
-    let base = pow(10, mag);
-
-    let digit = x / base;
-    print(stringForDigit(digit));
-
-    x = x % base;
-    mag = mag - 1;
-  );
-
-  print(stringForDigit(x % 10));
-);
-
-function println(s: String) = (
-  print(s);
-  print("\n");
-);