[wasm][asm.js] Require a number for fround literals.

src/asmjs/asm-typer.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/asmjs/asm-typer.h"
 
 #include <algorithm>
 #include <limits>
 #include <memory>
 #include <string>
@@ skipping 2836 matching lines @@
          "Invalid float type annotation - expected literal argument for call "
          "to fround.");
   }
 
   // ERRATA: 5.4
   // According to the spec: float constants must contain dots in local,
   // but not in globals.
   // However, the errata doc (and actual programs), use integer values
   // with fround(..).
   // Skipping the check that would go here to enforce this.
+  // Checking instead the literal expression is at least a number.
+  if (!src_expr->raw_value()->IsNumber()) {
+    FAIL(initializer,
+         "Invalid float type annotation - expected numeric literal for call "
+         "to fround.");
+  }
 
   return AsmType::Float();
 }
 
 // 5.5 GlobalVariableTypeAnnotations
 AsmType* AsmTyper::NewHeapView(CallNew* new_heap_view) {
   auto* heap_type = new_heap_view->expression()->AsProperty();
   if (heap_type == nullptr) {
     FAIL(new_heap_view, "Invalid type after new.");
   }
@@ skipping 43 matching lines @@
     return true;
   }
 
   *error_message = typer.error_message();
   return false;
 }
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8