ARM64: Use default-NaN mode to canonicalize NaNs.

src/arm64/code-stubs-arm64.cc

 // Copyright 2013 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 "v8.h"
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "bootstrapper.h"
 #include "code-stubs.h"
@@ skipping 1559 matching lines @@
   __ Peek(target, 3 * kPointerSize);
 
   __ LeaveExitFrame(save_doubles_, x10, true);
   ASSERT(jssp.Is(__ StackPointer()));
   // Pop or drop the remaining stack slots and return from the stub.
   //         jssp[24]:    Arguments array (of size argc), including receiver.
   //         jssp[16]:    Preserved x23 (used for target).
   //         jssp[8]:     Preserved x22 (used for argc).
   //         jssp[0]:     Preserved x21 (used for argv).
   __ Drop(x11);
+  __ AssertFPCRState();
   __ Ret();
 
   // The stack pointer is still csp if we aren't returning, and the frame
   // hasn't changed (except for the return address).
   __ SetStackPointer(csp);
 
   // Handling of exception.
   __ Bind(&exception_returned);
 
   // Retrieve the pending exception.
@@ skipping 63 matching lines @@
   // Push callee-saved registers and synchronize the system stack pointer (csp)
   // and the JavaScript stack pointer (jssp).
   //
   // We must not write to jssp until after the PushCalleeSavedRegisters()
   // call, since jssp is itself a callee-saved register.
   __ SetStackPointer(csp);
   __ PushCalleeSavedRegisters();
   __ Mov(jssp, csp);
   __ SetStackPointer(jssp);
 
+  // Configure the FPCR. We don't restore it, so this is technically not allowed
+  // according to AAPCS64. However, we only set default-NaN mode and this will
+  // be harmless for most C code. Also, it works for ARM.
+  __ ConfigureFPCR();
+
   ProfileEntryHookStub::MaybeCallEntryHook(masm);
 
   // Set up the reserved register for 0.0.
   __ Fmov(fp_zero, 0.0);
 
   // Build an entry frame (see layout below).
   int marker = is_construct ? StackFrame::ENTRY_CONSTRUCT : StackFrame::ENTRY;
   int64_t bad_frame_pointer = -1L;  // Bad frame pointer to fail if it is used.
   __ Mov(x13, bad_frame_pointer);
   __ Mov(x12, Smi::FromInt(marker));
@@ skipping 2953 matching lines @@
   // Array literal has ElementsKind of FAST_*_SMI_ELEMENTS or FAST_*_ELEMENTS,
   // and value is Smi.
   __ Bind(&smi_element);
   __ Ldr(x10, FieldMemOperand(array, JSObject::kElementsOffset));
   __ Add(x11, x10, Operand::UntagSmiAndScale(index_smi, kPointerSizeLog2));
   __ Str(value, FieldMemOperand(x11, FixedArray::kHeaderSize));
   __ Ret();
 
   __ Bind(&double_elements);
   __ Ldr(x10, FieldMemOperand(array, JSObject::kElementsOffset));
-  __ StoreNumberToDoubleElements(value, index_smi, x10, x11, d0, d1,
+  __ StoreNumberToDoubleElements(value, index_smi, x10, x11, d0,
                                  &slow_elements);
   __ Ret();
 }
 
 
 void StubFailureTrampolineStub::Generate(MacroAssembler* masm) {
   CEntryStub ces(isolate(), 1, fp_registers_ ? kSaveFPRegs : kDontSaveFPRegs);
   __ Call(ces.GetCode(), RelocInfo::CODE_TARGET);
   int parameter_count_offset =
       StubFailureTrampolineFrame::kCallerStackParameterCountFrameOffset;
@@ skipping 81 matching lines @@
   // and configure the stack pointer *before* doing the call.
   const Register old_stack_pointer = __ StackPointer();
   __ SetStackPointer(csp);
 
   // Put return address on the stack (accessible to GC through exit frame pc).
   __ Poke(lr, 0);
   // Call the C++ function.
   __ Blr(x10);
   // Return to calling code.
   __ Peek(lr, 0);
+  __ AssertFPCRState();
   __ Ret();
 
   __ SetStackPointer(old_stack_pointer);
 }
 
 void DirectCEntryStub::GenerateCall(MacroAssembler* masm,
                                     Register target) {
   // Make sure the caller configured the stack pointer (see comment in
   // DirectCEntryStub::Generate).
   ASSERT(csp.Is(__ StackPointer()));
@@ skipping 720 matching lines @@
                               MemOperand(fp, 6 * kPointerSize),
                               NULL);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM64