* resolving the location of a return address on the stack. Profilers that
* change the return address on the stack can use this to resolve the stack
* location to whereever the profiler stashed the original return address.
- * When invoked, return_addr_location will point to a location on stack where
- * a machine return address resides, this function should return either the
- * same pointer, or a pointer to the profiler's copy of the original return
- * address.
+ *
+ * \param return_addr_location points to a location on stack where a machine
+ * return address resides.
+ * \returns either return_addr_location, or else a pointer to the profiler's
+ * copy of the original return address.
+ *
+ * \note the resolver function must not cause garbage collection.
*/
typedef uintptr_t (*ReturnAddressLocationResolver)(
uintptr_t return_addr_location);
/**
+ * FunctionEntryHook is the type of the profile entry hook called at entry to
+ * any generated function when function-level profiling is enabled.
+ *
+ * \param function the address of the function that's being entered.
+ * \param return_addr_location points to a location on stack where the machine
+ * return address resides. This can be used to identify the caller of
+ * \p function, and/or modified to divert execution when \p function exits.
+ *
+ * \note the entry hook must not cause garbage collection.
+ */
+typedef void (*FunctionEntryHook)(uintptr_t function,
+ uintptr_t return_addr_location);
+
+
+/**
* Interface for iterating though all external resources in the heap.
*/
class V8EXPORT ExternalResourceVisitor { // NOLINT
ReturnAddressLocationResolver return_address_resolver);
/**
+ * Allows the host application to provide the address of a function that's
+ * invoked on entry to every V8-generated function.
+ * Note that \p entry_hook is invoked at the very start of each
+ * generated function.
+ *
+ * \param entry_hook a function that will be invoked on entry to every
+ * V8-generated function.
+ * \returns true on success on supported platforms, false on failure.
+ * \note Setting a new entry hook function when one is already active will
+ * fail.
+ */
+ static bool SetFunctionEntryHook(FunctionEntryHook entry_hook);
+
+ /**
* Adjusts the amount of registered external memory. Used to give
* V8 an indication of the amount of externally allocated memory
* that is kept alive by JavaScript objects. V8 uses this to decide
#include "../include/v8-profiler.h"
#include "../include/v8-testing.h"
#include "bootstrapper.h"
+#include "code-stubs.h"
#include "compiler.h"
#include "conversions-inl.h"
#include "counters.h"
}
+bool v8::V8::SetFunctionEntryHook(FunctionEntryHook entry_hook) {
+ return i::ProfileEntryHookStub::SetFunctionEntryHook(entry_hook);
+}
+
+
bool v8::V8::Dispose() {
i::Isolate* isolate = i::Isolate::Current();
if (!ApiCheck(isolate != NULL && isolate->IsDefaultIsolate(),
__ Ret();
}
+
+void ProfileEntryHookStub::MaybeCallEntryHook(MacroAssembler* masm) {
+ if (entry_hook_ != NULL) {
+ ProfileEntryHookStub stub;
+ __ push(lr);
+ __ CallStub(&stub);
+ __ pop(lr);
+ }
+}
+
+
+void ProfileEntryHookStub::Generate(MacroAssembler* masm) {
+ // The entry hook is a "push lr" instruction, followed by a call.
+ const int32_t kReturnAddressDistanceFromFunctionStart =
+ Assembler::kCallTargetAddressOffset + Assembler::kInstrSize;
+
+ // Save live volatile registers.
+ __ Push(lr, r5, r1);
+ const int32_t kNumSavedRegs = 3;
+
+ // Compute the function's address for the first argument.
+ __ sub(r0, lr, Operand(kReturnAddressDistanceFromFunctionStart));
+
+ // The caller's return address is above the saved temporaries.
+ // Grab that for the second argument to the hook.
+ __ add(r1, sp, Operand(kNumSavedRegs * kPointerSize));
+
+ // Align the stack if necessary.
+ int frame_alignment = masm->ActivationFrameAlignment();
+ if (frame_alignment > kPointerSize) {
+ __ mov(r5, sp);
+ ASSERT(IsPowerOf2(frame_alignment));
+ __ and_(sp, sp, Operand(-frame_alignment));
+ }
+
+#if defined(V8_HOST_ARCH_ARM)
+ __ mov(ip, Operand(reinterpret_cast<int32_t>(&entry_hook_)));
+ __ ldr(ip, MemOperand(ip));
+#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);
+ __ mov(ip, Operand(ExternalReference(&dispatcher,
+ ExternalReference::BUILTIN_CALL,
+ masm->isolate())));
+#endif
+ __ Call(ip);
+
+ // Restore the stack pointer if needed.
+ if (frame_alignment > kPointerSize) {
+ __ mov(sp, r5);
+ }
+
+ __ Pop(lr, r5, r1);
+ __ Ret();
+}
+
#undef __
} } // namespace v8::internal
SetFunctionPosition(function());
Comment cmnt(masm_, "[ function compiled by full code generator");
+ ProfileEntryHookStub::MaybeCallEntryHook(masm_);
+
#ifdef DEBUG
if (strlen(FLAG_stop_at) > 0 &&
info->function()->name()->IsEqualTo(CStrVector(FLAG_stop_at))) {
bool LCodeGen::GeneratePrologue() {
ASSERT(is_generating());
+ ProfileEntryHookStub::MaybeCallEntryHook(masm_);
+
#ifdef DEBUG
if (strlen(FLAG_stop_at) > 0 &&
info_->function()->name()->IsEqualTo(CStrVector(FLAG_stop_at))) {
KeyedStoreIC::GenerateRuntimeSetProperty(masm, strict_mode_);
}
+
+FunctionEntryHook ProfileEntryHookStub::entry_hook_ = NULL;
+
+
+void ProfileEntryHookStub::EntryHookTrampoline(intptr_t function,
+ intptr_t stack_pointer) {
+ if (entry_hook_ != NULL)
+ entry_hook_(function, stack_pointer);
+}
+
+
+bool ProfileEntryHookStub::SetFunctionEntryHook(FunctionEntryHook entry_hook) {
+ // We don't allow setting a new entry hook over one that's
+ // already active, as the hooks won't stack.
+ if (entry_hook != 0 && entry_hook_ != 0)
+ return false;
+
+ entry_hook_ = entry_hook;
+ return true;
+}
+
+
} } // namespace v8::internal
V(DebuggerStatement) \
V(StringDictionaryLookup) \
V(ElementsTransitionAndStore) \
- V(StoreArrayLiteralElement)
+ V(StoreArrayLiteralElement) \
+ V(ProfileEntryHook)
// List of code stubs only used on ARM platforms.
#ifdef V8_TARGET_ARCH_ARM
DISALLOW_COPY_AND_ASSIGN(StoreArrayLiteralElementStub);
};
+
+class ProfileEntryHookStub : public CodeStub {
+ public:
+ explicit ProfileEntryHookStub() {}
+
+ // The profile entry hook function is not allowed to cause a GC.
+ virtual bool SometimesSetsUpAFrame() { return false; }
+
+ // Generates a call to the entry hook if it's enabled.
+ static void MaybeCallEntryHook(MacroAssembler* masm);
+
+ // Sets or unsets the entry hook function. Returns true on success,
+ // false on an attempt to replace a non-NULL entry hook with another
+ // non-NULL hook.
+ static bool SetFunctionEntryHook(FunctionEntryHook entry_hook);
+
+ private:
+ static void EntryHookTrampoline(intptr_t function,
+ intptr_t stack_pointer);
+
+ Major MajorKey() { return ProfileEntryHook; }
+ int MinorKey() { return 0; }
+
+ void Generate(MacroAssembler* masm);
+
+ // The current function entry hook.
+ static FunctionEntryHook entry_hook_;
+
+ DISALLOW_COPY_AND_ASSIGN(ProfileEntryHookStub);
+};
+
} } // namespace v8::internal
#endif // V8_CODE_STUBS_H_
__ ret(0);
}
+
+void ProfileEntryHookStub::MaybeCallEntryHook(MacroAssembler* masm) {
+ if (entry_hook_ != NULL) {
+ ProfileEntryHookStub stub;
+ masm->CallStub(&stub);
+ }
+}
+
+
+void ProfileEntryHookStub::Generate(MacroAssembler* masm) {
+ // Ecx is the only volatile register we must save.
+ __ push(ecx);
+
+ // Calculate and push the original stack pointer.
+ __ lea(eax, Operand(esp, kPointerSize));
+ __ push(eax);
+
+ // Calculate and push the function address.
+ __ mov(eax, Operand(eax, 0));
+ __ sub(eax, Immediate(Assembler::kCallInstructionLength));
+ __ push(eax);
+
+ // Call the entry hook.
+ int32_t hook_location = reinterpret_cast<int32_t>(&entry_hook_);
+ __ call(Operand(hook_location, RelocInfo::NONE));
+ __ add(esp, Immediate(2 * kPointerSize));
+
+ // Restore ecx.
+ __ pop(ecx);
+ __ ret(0);
+}
+
#undef __
} } // namespace v8::internal
SetFunctionPosition(function());
Comment cmnt(masm_, "[ function compiled by full code generator");
+ ProfileEntryHookStub::MaybeCallEntryHook(masm_);
+
#ifdef DEBUG
if (strlen(FLAG_stop_at) > 0 &&
info->function()->name()->IsEqualTo(CStrVector(FLAG_stop_at))) {
return previous_;
}
-
#undef __
} } // namespace v8::internal
bool LCodeGen::GeneratePrologue() {
ASSERT(is_generating());
+ ProfileEntryHookStub::MaybeCallEntryHook(masm_);
+
#ifdef DEBUG
if (strlen(FLAG_stop_at) > 0 &&
info_->function()->name()->IsEqualTo(CStrVector(FLAG_stop_at))) {
__ ret(0);
}
+
+void ProfileEntryHookStub::MaybeCallEntryHook(MacroAssembler* masm) {
+ if (entry_hook_ != NULL) {
+ ProfileEntryHookStub stub;
+ masm->CallStub(&stub);
+ }
+}
+
+
+void ProfileEntryHookStub::Generate(MacroAssembler* masm) {
+ // Save volatile registers.
+#ifdef _WIN64
+ const int kNumSavedRegisters = 1;
+
+ __ push(rcx);
+#else
+ const int kNumSavedRegisters = 3;
+
+ __ push(rcx);
+ __ push(rdi);
+ __ push(rsi);
+#endif
+
+ // Calculate the original stack pointer and store it in the second arg.
+#ifdef _WIN64
+ __ lea(rdx, Operand(rsp, kNumSavedRegisters * kPointerSize));
+#else
+ __ lea(rsi, Operand(rsp, kNumSavedRegisters * kPointerSize));
+#endif
+
+ // Calculate the function address to the first arg.
+#ifdef _WIN64
+ __ movq(rcx, Operand(rdx, 0));
+ __ subq(rcx, Immediate(Assembler::kShortCallInstructionLength));
+#else
+ __ movq(rdi, Operand(rsi, 0));
+ __ subq(rdi, Immediate(Assembler::kShortCallInstructionLength));
+#endif
+
+ // Reserve stack for the first 4 args and align the stack.
+ __ movq(kScratchRegister, rsp);
+ __ subq(rsp, Immediate(4 * kPointerSize));
+ int frame_alignment = OS::ActivationFrameAlignment();
+ ASSERT(IsPowerOf2(frame_alignment));
+ __ and_(rsp, Immediate(-frame_alignment));
+
+ // Call the entry hook.
+ int64_t hook_location = reinterpret_cast<int64_t>(&entry_hook_);
+ __ movq(rax, hook_location, RelocInfo::NONE);
+ __ call(Operand(rax, 0));
+ __ movq(rsp, kScratchRegister);
+
+ // Restore volatile regs.
+#ifdef _WIN64
+ __ pop(rcx);
+#else
+ __ pop(rsi);
+ __ pop(rdi);
+ __ pop(rcx);
+#endif
+}
+
#undef __
} } // namespace v8::internal
SetFunctionPosition(function());
Comment cmnt(masm_, "[ function compiled by full code generator");
+ ProfileEntryHookStub::MaybeCallEntryHook(masm_);
+
#ifdef DEBUG
if (strlen(FLAG_stop_at) > 0 &&
info->function()->name()->IsEqualTo(CStrVector(FLAG_stop_at))) {
bool LCodeGen::GeneratePrologue() {
ASSERT(is_generating());
+ ProfileEntryHookStub::MaybeCallEntryHook(masm_);
+
#ifdef DEBUG
if (strlen(FLAG_stop_at) > 0 &&
info_->function()->name()->IsEqualTo(CStrVector(FLAG_stop_at))) {
#include "isolate.h"
#include "compilation-cache.h"
#include "execution.h"
+#include "objects.h"
#include "snapshot.h"
#include "platform.h"
#include "utils.h"
}
+static i::Handle<i::JSFunction>* foo_ptr = NULL;
+static int foo_count = 0;
+static i::Handle<i::JSFunction>* bar_ptr = NULL;
+static int bar_count = 0;
+
+
+static void entry_hook(uintptr_t function,
+ uintptr_t return_addr_location) {
+ i::Code* code = i::Code::GetCodeFromTargetAddress(
+ reinterpret_cast<i::Address>(function));
+ CHECK(code != NULL);
+
+ if (bar_ptr != NULL && code == (*bar_ptr)->code())
+ ++bar_count;
+
+ if (foo_ptr != NULL && code == (*foo_ptr)->code())
+ ++foo_count;
+
+ // TODO(siggi): Verify return_addr_location.
+}
+
+
+static void RunLoopInNewEnv() {
+ bar_ptr = NULL;
+ foo_ptr = NULL;
+
+ v8::HandleScope outer;
+ v8::Persistent<Context> env = Context::New();
+ env->Enter();
+
+ const char* script =
+ "function bar() {"
+ " var sum = 0;"
+ " for (i = 0; i < 100; ++i)"
+ " sum = foo(i);"
+ " return sum;"
+ "}"
+ "function foo(i) { return i * i; }";
+ CompileRun(script);
+ i::Handle<i::JSFunction> bar =
+ i::Handle<i::JSFunction>::cast(
+ v8::Utils::OpenHandle(*env->Global()->Get(v8_str("bar"))));
+ ASSERT(*bar);
+
+ i::Handle<i::JSFunction> foo =
+ i::Handle<i::JSFunction>::cast(
+ v8::Utils::OpenHandle(*env->Global()->Get(v8_str("foo"))));
+ ASSERT(*foo);
+
+ bar_ptr = &bar;
+ foo_ptr = &foo;
+
+ v8::Handle<v8::Value> value = CompileRun("bar();");
+ CHECK(value->IsNumber());
+ CHECK_EQ(9801.0, v8::Number::Cast(*value)->Value());
+
+ // Test the optimized codegen path.
+ value = CompileRun("%OptimizeFunctionOnNextCall(foo);"
+ "bar();");
+ CHECK(value->IsNumber());
+ CHECK_EQ(9801.0, v8::Number::Cast(*value)->Value());
+
+ env->Exit();
+}
+
+
+THREADED_TEST(SetFunctionEntryHook) {
+ i::FLAG_allow_natives_syntax = true;
+
+ // Test setting and resetting the entry hook.
+ // Nulling it should always succeed.
+ CHECK(v8::V8::SetFunctionEntryHook(NULL));
+
+ CHECK(v8::V8::SetFunctionEntryHook(entry_hook));
+ // Setting a hook while one's active should fail.
+ CHECK_EQ(false, v8::V8::SetFunctionEntryHook(entry_hook));
+
+ CHECK(v8::V8::SetFunctionEntryHook(NULL));
+
+ // Reset the entry count to zero and set the entry hook.
+ bar_count = 0;
+ foo_count = 0;
+ CHECK(v8::V8::SetFunctionEntryHook(entry_hook));
+ RunLoopInNewEnv();
+
+ CHECK_EQ(2, bar_count);
+ CHECK_EQ(200, foo_count);
+
+ // Clear the entry hook and count.
+ bar_count = 0;
+ foo_count = 0;
+ v8::V8::SetFunctionEntryHook(NULL);
+
+ // Clear the compilation cache to make sure we don't reuse the
+ // functions from the previous invocation.
+ v8::internal::Isolate::Current()->compilation_cache()->Clear();
+
+ // Verify that entry hooking is now disabled.
+ RunLoopInNewEnv();
+ CHECK(0u == bar_count);
+ CHECK(0u == foo_count);
+}
+
+
static int64_t cast(intptr_t x) { return static_cast<int64_t>(x); }