Change Math.random() to return 32 bits of random goodness, instead of 30 rand...

src/x64/codegen-x64.cc

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 4056 matching lines @@
   // RBP value is aligned, so it should be tagged as a smi (without necesarily
   // being padded as a smi, so it should not be treated as a smi.).
   ASSERT(kSmiTag == 0 && kSmiTagSize == 1);
   Result rbp_as_smi = allocator_->Allocate();
   ASSERT(rbp_as_smi.is_valid());
   __ movq(rbp_as_smi.reg(), rbp);
   frame_->Push(&rbp_as_smi);
 }
 
 
-void CodeGenerator::GenerateRandomPositiveSmi(ZoneList<Expression*>* args) {
+void CodeGenerator::GenerateRandomHeapNumber(
+    ZoneList<Expression*>* args) {
   ASSERT(args->length() == 0);
   frame_->SpillAll();
+
+  Label slow_allocate_heapnumber;
+  Label heapnumber_allocated;
+  __ AllocateHeapNumber(rdi, rbx, &slow_allocate_heapnumber);
+  __ jmp(&heapnumber_allocated);
+
+  __ bind(&slow_allocate_heapnumber);
+  // To allocate a heap number, and ensure that it is not a smi, we
+  // call the runtime function FUnaryMinus on 0, returning the double
+  // -0.0.  A new, distinct heap number is returned each time.
+  __ Push(Smi::FromInt(0));
+  __ CallRuntime(Runtime::kNumberUnaryMinus, 1);
+  __ movq(rdi, rax);
+
+  __ bind(&heapnumber_allocated);
+
+  // Put a random number into the heap number rdi using a C++ function.
+  // Return the heap number in rax.
+#ifdef _WIN64
+  __ movq(rcx, rdi);
+#else
+  // Callee-save in Microsoft 64-bit ABI, but not in AMD64 ABI.
   __ push(rsi);
-
-  static const int num_arguments = 0;
-  __ PrepareCallCFunction(num_arguments);
-
-  // Call V8::RandomPositiveSmi().
-  __ CallCFunction(ExternalReference::random_positive_smi_function(),
-                   num_arguments);
-
+#endif
+  __ PrepareCallCFunction(1);
+  __ CallCFunction(ExternalReference::fill_heap_number_with_random_function(),
+                   1);
+#ifndef _WIN64
+  // Callee-save in Microsoft 64-bit ABI, but not in AMD64 ABI.
   __ pop(rsi);
+#endif
   Result result = allocator_->Allocate(rax);
   frame_->Push(&result);
 }
 
 
 void CodeGenerator::GenerateRegExpExec(ZoneList<Expression*>* args) {
   ASSERT_EQ(args->length(), 4);
 
   // Load the arguments on the stack and call the runtime system.
   Load(args->at(0));
@@ skipping 5944 matching lines @@
   // Call the function from C++.
   return FUNCTION_CAST<ModuloFunction>(buffer);
 }
 
 #endif
 
 
 #undef __
 
 } }  // namespace v8::internal