Consider NaN falseish (#933)

Also makes isNaN and isFinite builtins again

Author: dcodeIO

src/builtins.ts

@@ -401,13 +401,6 @@ export class Flow {
     temps.push(local);
   }
 
-  /** Gets and immediately frees a temporary local of the specified type. */
-  getAndFreeTempLocal(type: Type, except: Set<i32> | null = null): Local {
-    var local = this.getTempLocal(type, except);
-    this.freeTempLocal(local);
-    return local;
-  }
-
   /** Gets the scoped local of the specified name. */
   getScopedLocal(name: string): Local | null {
     var scopedLocals = this.scopedLocals;

src/compiler.ts

@@ -1755,44 +1755,44 @@ export class Relooper {
   }
 }
 
-// export function hasSideEffects(expr: ExpressionRef): bool {
-//   // TODO: there's more
-//   switch (_BinaryenExpressionGetId(expr)) {
-//     case ExpressionId.LocalGet:
-//     case ExpressionId.GlobalGet:
-//     case ExpressionId.Const:
-//     case ExpressionId.Nop: {
-//       return false;
-//     }
-//     case ExpressionId.Block: {
-//       for (let i = 0, k = _BinaryenBlockGetNumChildren(expr); i < k; ++i) {
-//         if (hasSideEffects(_BinaryenBlockGetChild(expr, i))) return true;
-//       }
-//       return false;
-//     }
-//     case ExpressionId.If: {
-//       return hasSideEffects(_BinaryenIfGetCondition(expr))
-//           || hasSideEffects(_BinaryenIfGetIfTrue(expr))
-//           || hasSideEffects(_BinaryenIfGetIfFalse(expr));
-//     }
-//     case ExpressionId.Unary: {
-//       return hasSideEffects(_BinaryenUnaryGetValue(expr));
-//     }
-//     case ExpressionId.Binary: {
-//       return hasSideEffects(_BinaryenBinaryGetLeft(expr))
-//           || hasSideEffects(_BinaryenBinaryGetRight(expr));
-//     }
-//     case ExpressionId.Drop: {
-//       return hasSideEffects(_BinaryenDropGetValue(expr));
-//     }
-//     case ExpressionId.Select: {
-//       return hasSideEffects(_BinaryenSelectGetIfTrue(expr))
-//           || hasSideEffects(_BinaryenSelectGetIfFalse(expr))
-//           || hasSideEffects(_BinaryenSelectGetCondition(expr));
-//     }
-//   }
-//   return true;
-// }
+export function hasSideEffects(expr: ExpressionRef): bool {
+  // TODO: there's more
+  switch (_BinaryenExpressionGetId(expr)) {
+    case ExpressionId.LocalGet:
+    case ExpressionId.GlobalGet:
+    case ExpressionId.Const:
+    case ExpressionId.Nop: {
+      return false;
+    }
+    case ExpressionId.Block: {
+      for (let i = 0, k = _BinaryenBlockGetNumChildren(expr); i < k; ++i) {
+        if (hasSideEffects(_BinaryenBlockGetChild(expr, i))) return true;
+      }
+      return false;
+    }
+    case ExpressionId.If: {
+      return hasSideEffects(_BinaryenIfGetCondition(expr))
+          || hasSideEffects(_BinaryenIfGetIfTrue(expr))
+          || hasSideEffects(_BinaryenIfGetIfFalse(expr));
+    }
+    case ExpressionId.Unary: {
+      return hasSideEffects(_BinaryenUnaryGetValue(expr));
+    }
+    case ExpressionId.Binary: {
+      return hasSideEffects(_BinaryenBinaryGetLeft(expr))
+          || hasSideEffects(_BinaryenBinaryGetRight(expr));
+    }
+    case ExpressionId.Drop: {
+      return hasSideEffects(_BinaryenDropGetValue(expr));
+    }
+    case ExpressionId.Select: {
+      return hasSideEffects(_BinaryenSelectGetIfTrue(expr))
+          || hasSideEffects(_BinaryenSelectGetIfFalse(expr))
+          || hasSideEffects(_BinaryenSelectGetCondition(expr));
+    }
+  }
+  return true;
+}
 
 // helpers
 // can't do stack allocation here: STACKTOP is a global in WASM but a hidden variable in asm.js

src/flow.ts

@@ -999,10 +999,10 @@ export class Program extends DiagnosticEmitter {
     return this.resolver.resolveFunction(<FunctionPrototype>prototype, null);
   }
 
-  /** Requires that a non-generic global function is present and returns it. */
-  private requireFunction(name: string): Function {
+  /** Requires that a global function is present and returns it. */
+  private requireFunction(name: string, typeArguments: Type[] | null = null): Function {
     var prototype = this.require(name, ElementKind.FUNCTION_PROTOTYPE);
-    var resolved = this.resolver.resolveFunction(<FunctionPrototype>prototype, null);
+    var resolved = this.resolver.resolveFunction(<FunctionPrototype>prototype, typeArguments);
     if (!resolved) throw new Error("invalid " + name);
     return resolved;
   }

src/module.ts

@@ -9,19 +9,13 @@ export const NaN: f64 = 0 / 0;
 @builtin @inline
 export const Infinity: f64 = 1 / 0;
 
-export function isNaN<T extends number>(value: T): bool {
-  if (!isFloat<T>()) {
-    if (!isInteger<T>()) ERROR("numeric type expected");
-  }
-  return value != value;
-}
+// @ts-ignore: decorator
+@builtin
+export declare function isNaN<T extends number>(value: T): bool;
 
-export function isFinite<T extends number>(value: T): bool {
-  if (!isFloat<T>()) {
-    if (!isInteger<T>()) ERROR("numeric type expected");
-  }
-  return value - value == 0;
-}
+// @ts-ignore: decorator
+@builtin
+export declare function isFinite<T extends number>(value: T): bool;
 
 @sealed @unmanaged
 export abstract class I8 {