Accurate function prototypes for native calls from ARM simulator.

src/x64/code-stubs-x64.cc

Index: src/x64/code-stubs-x64.cc
diff --git a/src/x64/code-stubs-x64.cc b/src/x64/code-stubs-x64.cc
index 3a9a0234e2e8ed1d1f511687c6f26a493aef21f3..aba2a3835555f379ca5eb5b7ce9b011604e4c594 100644
--- a/src/x64/code-stubs-x64.cc
+++ b/src/x64/code-stubs-x64.cc
@@ -30,6 +30,7 @@
 #if defined(V8_TARGET_ARCH_X64)
 
 #include "bootstrapper.h"
+#include "builtins-decls.h"
 #include "code-stubs.h"
 #include "regexp-macro-assembler.h"
 #include "stub-cache.h"
@@ -4106,22 +4107,23 @@ void CEntryStub::GenerateCore(MacroAssembler* masm,
 
   // Call C function.
 #ifdef _WIN64
-  // Windows 64-bit ABI passes arguments in rcx, rdx, r8, r9
-  // Store Arguments object on stack, below the 4 WIN64 ABI parameter slots.
-  __ movq(StackSpaceOperand(0), r14);  // argc.
-  __ movq(StackSpaceOperand(1), r15);  // argv.
+  // Windows 64-bit ABI passes arguments in rcx, rdx, r8, r9.
+  // Pass argv and argc as two parameters. The arguments object will
+  // be created by stubs declared by DECLARE_RUNTIME_FUNCTION().
   if (result_size_ < 2) {
     // Pass a pointer to the Arguments object as the first argument.
     // Return result in single register (rax).
-    __ lea(rcx, StackSpaceOperand(0));
-    __ LoadAddress(rdx, ExternalReference::isolate_address(masm->isolate()));
+    __ movq(rcx, r14);  // argc.
+    __ movq(rdx, r15);  // argv.
+    __ movq(r8, ExternalReference::isolate_address(masm->isolate()));
   } else {
     ASSERT_EQ(2, result_size_);
     // Pass a pointer to the result location as the first argument.
     __ lea(rcx, StackSpaceOperand(2));
     // Pass a pointer to the Arguments object as the second argument.
-    __ lea(rdx, StackSpaceOperand(0));
-    __ LoadAddress(r8, ExternalReference::isolate_address(masm->isolate()));
+    __ movq(rdx, r14);  // argc.
+    __ movq(r8, r15);   // argv.
+    __ movq(r9, ExternalReference::isolate_address(masm->isolate()));
   }
 
 #else  // _WIN64