MIPS: Improved function entry hook coverage.

src/mips/code-stubs-mips.cc

 // Copyright 2012 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 3512 matching lines @@
 
 void CEntryStub::Generate(MacroAssembler* masm) {
   // Called from JavaScript; parameters are on stack as if calling JS function
   // s0: number of arguments including receiver
   // s1: size of arguments excluding receiver
   // s2: pointer to builtin function
   // fp: frame pointer    (restored after C call)
   // sp: stack pointer    (restored as callee's sp after C call)
   // cp: current context  (C callee-saved)
 
+  ProfileEntryHookStub::MaybeCallEntryHook(masm);
+
   // NOTE: Invocations of builtins may return failure objects
   // instead of a proper result. The builtin entry handles
   // this by performing a garbage collection and retrying the
   // builtin once.
 
   // NOTE: s0-s2 hold the arguments of this function instead of a0-a2.
   // The reason for this is that these arguments would need to be saved anyway
   // so it's faster to set them up directly.
   // See MacroAssembler::PrepareCEntryArgs and PrepareCEntryFunction.
 
@@ skipping 73 matching lines @@
   // Registers:
   // a0: entry address
   // a1: function
   // a2: receiver
   // a3: argc
   //
   // Stack:
   // 4 args slots
   // args
 
+  ProfileEntryHookStub::MaybeCallEntryHook(masm);
+
   // Save callee saved registers on the stack.
   __ MultiPush(kCalleeSaved | ra.bit());
 
   // Save callee-saved FPU registers.
   __ MultiPushFPU(kCalleeSavedFPU);
   // Set up the reserved register for 0.0.
   __ Move(kDoubleRegZero, 0.0);
 
 
   // Load argv in s0 register.
@@ skipping 3867 matching lines @@
     __ Addu(a1, a1, Operand(1));
   }
   masm->LeaveFrame(StackFrame::STUB_FAILURE_TRAMPOLINE);
   __ sll(a1, a1, kPointerSizeLog2);
   __ Ret(USE_DELAY_SLOT);
   __ Addu(sp, sp, a1);
 }
 
 
 void ProfileEntryHookStub::MaybeCallEntryHook(MacroAssembler* masm) {
-  if (entry_hook_ != NULL) {
+  if (masm->isolate()->function_entry_hook() != NULL) {
+    AllowStubCallsScope allow_stub_calls(masm, true);
     ProfileEntryHookStub stub;
     __ push(ra);
     __ CallStub(&stub);
     __ pop(ra);
   }
 }
 
 
 void ProfileEntryHookStub::Generate(MacroAssembler* masm) {
   // The entry hook is a "push ra" instruction, followed by a call.
   // Note: on MIPS "push" is 2 instruction
   const int32_t kReturnAddressDistanceFromFunctionStart =
       Assembler::kCallTargetAddressOffset + (2 * Assembler::kInstrSize);
 
   // Save live volatile registers.
-  __ Push(ra, t1, a1);
-  const int32_t kNumSavedRegs = 3;
+  // We also save ra, so the count here is one higher than the mask indicates.
+  const int32_t kNumSavedRegs = kNumJSCallerSaved + 1;
+
+  // Save all caller-save registers as this may be called from anywhere.
+  __ MultiPush(kJSCallerSaved | ra.bit());
 
   // Compute the function's address for the first argument.
   __ Subu(a0, ra, Operand(kReturnAddressDistanceFromFunctionStart));
 
   // The caller's return address is above the saved temporaries.
   // Grab that for the second argument to the hook.
   __ Addu(a1, sp, Operand(kNumSavedRegs * kPointerSize));
 
   // Align the stack if necessary.
   int frame_alignment = masm->ActivationFrameAlignment();
   if (frame_alignment > kPointerSize) {
     __ mov(t1, sp);
     ASSERT(IsPowerOf2(frame_alignment));
     __ And(sp, sp, Operand(-frame_alignment));
   }
 
-#if V8_HOST_ARCH_MIPS
-  __ li(at, Operand(reinterpret_cast<int32_t>(&entry_hook_)));
-  __ lw(at, MemOperand(at));
+#if defined(V8_HOST_ARCH_MIPS)
+  int32_t entry_hook =
+      reinterpret_cast<int32_t>(masm->isolate()->function_entry_hook());
+  __ li(at, Operand(entry_hook));
 #else
   // Under the simulator we need to indirect the entry hook through a
   // trampoline function at a known address.
-  Address trampoline_address = reinterpret_cast<Address>(
-      reinterpret_cast<intptr_t>(EntryHookTrampoline));
-  ApiFunction dispatcher(trampoline_address);
+  ApiFunction dispatcher(FUNCTION_ADDR(EntryHookTrampoline));
   __ li(at, Operand(ExternalReference(&dispatcher,
                                       ExternalReference::BUILTIN_CALL,
                                       masm->isolate())));
 #endif
   __ Call(at);
 
   // Restore the stack pointer if needed.
   if (frame_alignment > kPointerSize) {
     __ mov(sp, t1);
   }
 
-  __ Pop(ra, t1, a1);
+  // Also pop ra to get Ret(0).
+  __ MultiPop(kJSCallerSaved | ra.bit());
   __ Ret();
 }
 
 
 template<class T>
 static void CreateArrayDispatch(MacroAssembler* masm) {
   int last_index = GetSequenceIndexFromFastElementsKind(
       TERMINAL_FAST_ELEMENTS_KIND);
   for (int i = 0; i <= last_index; ++i) {
     Label next;
@@ skipping 259 matching lines @@
   __ bind(&fast_elements_case);
   GenerateCase(masm, FAST_ELEMENTS);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS