// Copyright 2006-2008 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 // with the distribution. // * Neither the name of Google Inc. nor the names of its // contributors may be used to endorse or promote products derived // from this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. #include "v8.h" #include "bootstrapper.h" #include "codegen-inl.h" #include "debug.h" #include "runtime.h" namespace v8 { namespace internal { // Give alias names to registers Register cp = { 8 }; // JavaScript context pointer Register pp = { 10 }; // parameter pointer MacroAssembler::MacroAssembler(void* buffer, int size) : Assembler(buffer, size), unresolved_(0), generating_stub_(false), allow_stub_calls_(true), code_object_(Heap::undefined_value()) { } // We always generate arm code, never thumb code, even if V8 is compiled to // thumb, so we require inter-working support #if defined(__thumb__) && !defined(__THUMB_INTERWORK__) #error "flag -mthumb-interwork missing" #endif // We do not support thumb inter-working with an arm architecture not supporting // the blx instruction (below v5t) #if defined(__THUMB_INTERWORK__) #if !defined(__ARM_ARCH_5T__) && \ !defined(__ARM_ARCH_5TE__) && \ !defined(__ARM_ARCH_7A__) && \ !defined(__ARM_ARCH_7__) // add tests for other versions above v5t as required #error "for thumb inter-working we require architecture v5t or above" #endif #endif // Using blx may yield better code, so use it when required or when available #if defined(__THUMB_INTERWORK__) || defined(__ARM_ARCH_5__) #define USE_BLX 1 #endif // Using bx does not yield better code, so use it only when required #if defined(__THUMB_INTERWORK__) #define USE_BX 1 #endif void MacroAssembler::Jump(Register target, Condition cond) { #if USE_BX bx(target, cond); #else mov(pc, Operand(target), LeaveCC, cond); #endif } void MacroAssembler::Jump(intptr_t target, RelocInfo::Mode rmode, Condition cond) { #if USE_BX mov(ip, Operand(target, rmode), LeaveCC, cond); bx(ip, cond); #else mov(pc, Operand(target, rmode), LeaveCC, cond); #endif } void MacroAssembler::Jump(byte* target, RelocInfo::Mode rmode, Condition cond) { ASSERT(!RelocInfo::IsCodeTarget(rmode)); Jump(reinterpret_cast(target), rmode, cond); } void MacroAssembler::Jump(Handle code, RelocInfo::Mode rmode, Condition cond) { ASSERT(RelocInfo::IsCodeTarget(rmode)); // 'code' is always generated ARM code, never THUMB code Jump(reinterpret_cast(code.location()), rmode, cond); } void MacroAssembler::Call(Register target, Condition cond) { #if USE_BLX blx(target, cond); #else // set lr for return at current pc + 8 mov(lr, Operand(pc), LeaveCC, cond); mov(pc, Operand(target), LeaveCC, cond); #endif } void MacroAssembler::Call(intptr_t target, RelocInfo::Mode rmode, Condition cond) { #if !defined(__arm__) if (rmode == RelocInfo::RUNTIME_ENTRY) { mov(r2, Operand(target, rmode), LeaveCC, cond); // Set lr for return at current pc + 8. mov(lr, Operand(pc), LeaveCC, cond); // Emit a ldr pc, [pc + offset of target in constant pool]. // Notify the simulator of the transition to C code. swi(assembler::arm::call_rt_r2); } else { // set lr for return at current pc + 8 mov(lr, Operand(pc), LeaveCC, cond); // emit a ldr pc, [pc + offset of target in constant pool] mov(pc, Operand(target, rmode), LeaveCC, cond); } #else // Set lr for return at current pc + 8. mov(lr, Operand(pc), LeaveCC, cond); // Emit a ldr pc, [pc + offset of target in constant pool]. mov(pc, Operand(target, rmode), LeaveCC, cond); #endif // !defined(__arm__) // If USE_BLX is defined, we could emit a 'mov ip, target', followed by a // 'blx ip'; however, the code would not be shorter than the above sequence // and the target address of the call would be referenced by the first // instruction rather than the second one, which would make it harder to patch // (two instructions before the return address, instead of one). ASSERT(kTargetAddrToReturnAddrDist == sizeof(Instr)); } void MacroAssembler::Call(byte* target, RelocInfo::Mode rmode, Condition cond) { ASSERT(!RelocInfo::IsCodeTarget(rmode)); Call(reinterpret_cast(target), rmode, cond); } void MacroAssembler::Call(Handle code, RelocInfo::Mode rmode, Condition cond) { ASSERT(RelocInfo::IsCodeTarget(rmode)); // 'code' is always generated ARM code, never THUMB code Call(reinterpret_cast(code.location()), rmode, cond); } void MacroAssembler::Ret(Condition cond) { #if USE_BX bx(lr, cond); #else mov(pc, Operand(lr), LeaveCC, cond); #endif } void MacroAssembler::SmiJumpTable(Register index, Vector targets) { // Empty the const pool. CheckConstPool(true, true); add(pc, pc, Operand(index, LSL, assembler::arm::Instr::kInstrSizeLog2 - kSmiTagSize)); BlockConstPoolBefore(pc_offset() + (targets.length() + 1) * sizeof(Instr)); nop(); // Jump table alignment. for (int i = 0; i < targets.length(); i++) { b(targets[i]); } } // Will clobber 4 registers: object, offset, scratch, ip. The // register 'object' contains a heap object pointer. The heap object // tag is shifted away. void MacroAssembler::RecordWrite(Register object, Register offset, Register scratch) { // This is how much we shift the remembered set bit offset to get the // offset of the word in the remembered set. We divide by kBitsPerInt (32, // shift right 5) and then multiply by kIntSize (4, shift left 2). const int kRSetWordShift = 3; Label fast, done; // First, test that the object is not in the new space. We cannot set // remembered set bits in the new space. // object: heap object pointer (with tag) // offset: offset to store location from the object and_(scratch, object, Operand(Heap::NewSpaceMask())); cmp(scratch, Operand(ExternalReference::new_space_start())); b(eq, &done); // Compute the bit offset in the remembered set. // object: heap object pointer (with tag) // offset: offset to store location from the object mov(ip, Operand(Page::kPageAlignmentMask)); // load mask only once and_(scratch, object, Operand(ip)); // offset into page of the object add(offset, scratch, Operand(offset)); // add offset into the object mov(offset, Operand(offset, LSR, kObjectAlignmentBits)); // Compute the page address from the heap object pointer. // object: heap object pointer (with tag) // offset: bit offset of store position in the remembered set bic(object, object, Operand(ip)); // If the bit offset lies beyond the normal remembered set range, it is in // the extra remembered set area of a large object. // object: page start // offset: bit offset of store position in the remembered set cmp(offset, Operand(Page::kPageSize / kPointerSize)); b(lt, &fast); // Adjust the bit offset to be relative to the start of the extra // remembered set and the start address to be the address of the extra // remembered set. sub(offset, offset, Operand(Page::kPageSize / kPointerSize)); // Load the array length into 'scratch' and multiply by four to get the // size in bytes of the elements. ldr(scratch, MemOperand(object, Page::kObjectStartOffset + FixedArray::kLengthOffset)); mov(scratch, Operand(scratch, LSL, kObjectAlignmentBits)); // Add the page header (including remembered set), array header, and array // body size to the page address. add(object, object, Operand(Page::kObjectStartOffset + Array::kHeaderSize)); add(object, object, Operand(scratch)); bind(&fast); // Get address of the rset word. // object: start of the remembered set (page start for the fast case) // offset: bit offset of store position in the remembered set bic(scratch, offset, Operand(kBitsPerInt - 1)); // clear the bit offset add(object, object, Operand(scratch, LSR, kRSetWordShift)); // Get bit offset in the rset word. // object: address of remembered set word // offset: bit offset of store position and_(offset, offset, Operand(kBitsPerInt - 1)); ldr(scratch, MemOperand(object)); mov(ip, Operand(1)); orr(scratch, scratch, Operand(ip, LSL, offset)); str(scratch, MemOperand(object)); bind(&done); } void MacroAssembler::EnterFrame(StackFrame::Type type) { // r0-r3: preserved stm(db_w, sp, cp.bit() | fp.bit() | lr.bit()); mov(ip, Operand(Smi::FromInt(type))); push(ip); mov(ip, Operand(CodeObject())); push(ip); add(fp, sp, Operand(3 * kPointerSize)); // Adjust FP to point to saved FP. } void MacroAssembler::LeaveFrame(StackFrame::Type type) { // r0: preserved // r1: preserved // r2: preserved // Drop the execution stack down to the frame pointer and restore // the caller frame pointer and return address. mov(sp, fp); ldm(ia_w, sp, fp.bit() | lr.bit()); } void MacroAssembler::EnterExitFrame(StackFrame::Type type) { ASSERT(type == StackFrame::EXIT || type == StackFrame::EXIT_DEBUG); // Compute the argv pointer and keep it in a callee-saved register. // r0 is argc. add(r6, sp, Operand(r0, LSL, kPointerSizeLog2)); sub(r6, r6, Operand(kPointerSize)); // Compute parameter pointer before making changes and save it as ip // register so that it is restored as sp register on exit, thereby // popping the args. // ip = sp + kPointerSize * #args; add(ip, sp, Operand(r0, LSL, kPointerSizeLog2)); // Align the stack at this point. After this point we have 5 pushes, // so in fact we have to unalign here! See also the assert on the // alignment immediately below. if (OS::ActivationFrameAlignment() != kPointerSize) { // This code needs to be made more general if this assert doesn't hold. ASSERT(OS::ActivationFrameAlignment() == 2 * kPointerSize); mov(r7, Operand(Smi::FromInt(0))); tst(sp, Operand(OS::ActivationFrameAlignment() - 1)); push(r7, eq); // Conditional push instruction. } // Push in reverse order: caller_fp, sp_on_exit, and caller_pc. stm(db_w, sp, fp.bit() | ip.bit() | lr.bit()); mov(fp, Operand(sp)); // setup new frame pointer // Push debug marker. mov(ip, Operand(type == StackFrame::EXIT_DEBUG ? 1 : 0)); push(ip); // Save the frame pointer and the context in top. mov(ip, Operand(ExternalReference(Top::k_c_entry_fp_address))); str(fp, MemOperand(ip)); mov(ip, Operand(ExternalReference(Top::k_context_address))); str(cp, MemOperand(ip)); // Setup argc and the builtin function in callee-saved registers. mov(r4, Operand(r0)); mov(r5, Operand(r1)); #ifdef ENABLE_DEBUGGER_SUPPORT // Save the state of all registers to the stack from the memory // location. This is needed to allow nested break points. if (type == StackFrame::EXIT_DEBUG) { // Use sp as base to push. CopyRegistersFromMemoryToStack(sp, kJSCallerSaved); } #endif } void MacroAssembler::LeaveExitFrame(StackFrame::Type type) { #ifdef ENABLE_DEBUGGER_SUPPORT // Restore the memory copy of the registers by digging them out from // the stack. This is needed to allow nested break points. if (type == StackFrame::EXIT_DEBUG) { // This code intentionally clobbers r2 and r3. const int kCallerSavedSize = kNumJSCallerSaved * kPointerSize; const int kOffset = ExitFrameConstants::kDebugMarkOffset - kCallerSavedSize; add(r3, fp, Operand(kOffset)); CopyRegistersFromStackToMemory(r3, r2, kJSCallerSaved); } #endif // Clear top frame. mov(r3, Operand(0)); mov(ip, Operand(ExternalReference(Top::k_c_entry_fp_address))); str(r3, MemOperand(ip)); // Restore current context from top and clear it in debug mode. mov(ip, Operand(ExternalReference(Top::k_context_address))); ldr(cp, MemOperand(ip)); #ifdef DEBUG str(r3, MemOperand(ip)); #endif // Pop the arguments, restore registers, and return. mov(sp, Operand(fp)); // respect ABI stack constraint ldm(ia, sp, fp.bit() | sp.bit() | pc.bit()); } void MacroAssembler::InvokePrologue(const ParameterCount& expected, const ParameterCount& actual, Handle code_constant, Register code_reg, Label* done, InvokeFlag flag) { bool definitely_matches = false; Label regular_invoke; // Check whether the expected and actual arguments count match. If not, // setup registers according to contract with ArgumentsAdaptorTrampoline: // r0: actual arguments count // r1: function (passed through to callee) // r2: expected arguments count // r3: callee code entry // The code below is made a lot easier because the calling code already sets // up actual and expected registers according to the contract if values are // passed in registers. ASSERT(actual.is_immediate() || actual.reg().is(r0)); ASSERT(expected.is_immediate() || expected.reg().is(r2)); ASSERT((!code_constant.is_null() && code_reg.is(no_reg)) || code_reg.is(r3)); if (expected.is_immediate()) { ASSERT(actual.is_immediate()); if (expected.immediate() == actual.immediate()) { definitely_matches = true; } else { mov(r0, Operand(actual.immediate())); const int sentinel = SharedFunctionInfo::kDontAdaptArgumentsSentinel; if (expected.immediate() == sentinel) { // Don't worry about adapting arguments for builtins that // don't want that done. Skip adaption code by making it look // like we have a match between expected and actual number of // arguments. definitely_matches = true; } else { mov(r2, Operand(expected.immediate())); } } } else { if (actual.is_immediate()) { cmp(expected.reg(), Operand(actual.immediate())); b(eq, ®ular_invoke); mov(r0, Operand(actual.immediate())); } else { cmp(expected.reg(), Operand(actual.reg())); b(eq, ®ular_invoke); } } if (!definitely_matches) { if (!code_constant.is_null()) { mov(r3, Operand(code_constant)); add(r3, r3, Operand(Code::kHeaderSize - kHeapObjectTag)); } Handle adaptor = Handle(Builtins::builtin(Builtins::ArgumentsAdaptorTrampoline)); if (flag == CALL_FUNCTION) { Call(adaptor, RelocInfo::CODE_TARGET); b(done); } else { Jump(adaptor, RelocInfo::CODE_TARGET); } bind(®ular_invoke); } } void MacroAssembler::InvokeCode(Register code, const ParameterCount& expected, const ParameterCount& actual, InvokeFlag flag) { Label done; InvokePrologue(expected, actual, Handle::null(), code, &done, flag); if (flag == CALL_FUNCTION) { Call(code); } else { ASSERT(flag == JUMP_FUNCTION); Jump(code); } // Continue here if InvokePrologue does handle the invocation due to // mismatched parameter counts. bind(&done); } void MacroAssembler::InvokeCode(Handle code, const ParameterCount& expected, const ParameterCount& actual, RelocInfo::Mode rmode, InvokeFlag flag) { Label done; InvokePrologue(expected, actual, code, no_reg, &done, flag); if (flag == CALL_FUNCTION) { Call(code, rmode); } else { Jump(code, rmode); } // Continue here if InvokePrologue does handle the invocation due to // mismatched parameter counts. bind(&done); } void MacroAssembler::InvokeFunction(Register fun, const ParameterCount& actual, InvokeFlag flag) { // Contract with called JS functions requires that function is passed in r1. ASSERT(fun.is(r1)); Register expected_reg = r2; Register code_reg = r3; ldr(code_reg, FieldMemOperand(r1, JSFunction::kSharedFunctionInfoOffset)); ldr(cp, FieldMemOperand(r1, JSFunction::kContextOffset)); ldr(expected_reg, FieldMemOperand(code_reg, SharedFunctionInfo::kFormalParameterCountOffset)); ldr(code_reg, MemOperand(code_reg, SharedFunctionInfo::kCodeOffset - kHeapObjectTag)); add(code_reg, code_reg, Operand(Code::kHeaderSize - kHeapObjectTag)); ParameterCount expected(expected_reg); InvokeCode(code_reg, expected, actual, flag); } #ifdef ENABLE_DEBUGGER_SUPPORT void MacroAssembler::SaveRegistersToMemory(RegList regs) { ASSERT((regs & ~kJSCallerSaved) == 0); // Copy the content of registers to memory location. for (int i = 0; i < kNumJSCallerSaved; i++) { int r = JSCallerSavedCode(i); if ((regs & (1 << r)) != 0) { Register reg = { r }; mov(ip, Operand(ExternalReference(Debug_Address::Register(i)))); str(reg, MemOperand(ip)); } } } void MacroAssembler::RestoreRegistersFromMemory(RegList regs) { ASSERT((regs & ~kJSCallerSaved) == 0); // Copy the content of memory location to registers. for (int i = kNumJSCallerSaved; --i >= 0;) { int r = JSCallerSavedCode(i); if ((regs & (1 << r)) != 0) { Register reg = { r }; mov(ip, Operand(ExternalReference(Debug_Address::Register(i)))); ldr(reg, MemOperand(ip)); } } } void MacroAssembler::CopyRegistersFromMemoryToStack(Register base, RegList regs) { ASSERT((regs & ~kJSCallerSaved) == 0); // Copy the content of the memory location to the stack and adjust base. for (int i = kNumJSCallerSaved; --i >= 0;) { int r = JSCallerSavedCode(i); if ((regs & (1 << r)) != 0) { mov(ip, Operand(ExternalReference(Debug_Address::Register(i)))); ldr(ip, MemOperand(ip)); str(ip, MemOperand(base, 4, NegPreIndex)); } } } void MacroAssembler::CopyRegistersFromStackToMemory(Register base, Register scratch, RegList regs) { ASSERT((regs & ~kJSCallerSaved) == 0); // Copy the content of the stack to the memory location and adjust base. for (int i = 0; i < kNumJSCallerSaved; i++) { int r = JSCallerSavedCode(i); if ((regs & (1 << r)) != 0) { mov(ip, Operand(ExternalReference(Debug_Address::Register(i)))); ldr(scratch, MemOperand(base, 4, PostIndex)); str(scratch, MemOperand(ip)); } } } #endif void MacroAssembler::PushTryHandler(CodeLocation try_location, HandlerType type) { ASSERT(StackHandlerConstants::kSize == 6 * kPointerSize); // adjust this code // The pc (return address) is passed in register lr. if (try_location == IN_JAVASCRIPT) { stm(db_w, sp, pp.bit() | fp.bit() | lr.bit()); if (type == TRY_CATCH_HANDLER) { mov(r3, Operand(StackHandler::TRY_CATCH)); } else { mov(r3, Operand(StackHandler::TRY_FINALLY)); } push(r3); // state mov(r3, Operand(ExternalReference(Top::k_handler_address))); ldr(r1, MemOperand(r3)); push(r1); // next sp str(sp, MemOperand(r3)); // chain handler mov(r0, Operand(Smi::FromInt(StackHandler::kCodeNotPresent))); // new TOS push(r0); } else { // Must preserve r0-r4, r5-r7 are available. ASSERT(try_location == IN_JS_ENTRY); // The parameter pointer is meaningless here and fp does not point to a JS // frame. So we save NULL for both pp and fp. We expect the code throwing an // exception to check fp before dereferencing it to restore the context. mov(pp, Operand(0)); // set pp to NULL mov(ip, Operand(0)); // to save a NULL fp stm(db_w, sp, pp.bit() | ip.bit() | lr.bit()); mov(r6, Operand(StackHandler::ENTRY)); push(r6); // state mov(r7, Operand(ExternalReference(Top::k_handler_address))); ldr(r6, MemOperand(r7)); push(r6); // next sp str(sp, MemOperand(r7)); // chain handler mov(r5, Operand(Smi::FromInt(StackHandler::kCodeNotPresent))); // new TOS push(r5); // flush TOS } } Register MacroAssembler::CheckMaps(JSObject* object, Register object_reg, JSObject* holder, Register holder_reg, Register scratch, Label* miss) { // Make sure there's no overlap between scratch and the other // registers. ASSERT(!scratch.is(object_reg) && !scratch.is(holder_reg)); // Keep track of the current object in register reg. Register reg = object_reg; int depth = 1; // Check the maps in the prototype chain. // Traverse the prototype chain from the object and do map checks. while (object != holder) { depth++; // Only global objects and objects that do not require access // checks are allowed in stubs. ASSERT(object->IsJSGlobalProxy() || !object->IsAccessCheckNeeded()); // Get the map of the current object. ldr(scratch, FieldMemOperand(reg, HeapObject::kMapOffset)); cmp(scratch, Operand(Handle(object->map()))); // Branch on the result of the map check. b(ne, miss); // Check access rights to the global object. This has to happen // after the map check so that we know that the object is // actually a global object. if (object->IsJSGlobalProxy()) { CheckAccessGlobalProxy(reg, scratch, miss); // Restore scratch register to be the map of the object. In the // new space case below, we load the prototype from the map in // the scratch register. ldr(scratch, FieldMemOperand(reg, HeapObject::kMapOffset)); } reg = holder_reg; // from now the object is in holder_reg JSObject* prototype = JSObject::cast(object->GetPrototype()); if (Heap::InNewSpace(prototype)) { // The prototype is in new space; we cannot store a reference // to it in the code. Load it from the map. ldr(reg, FieldMemOperand(scratch, Map::kPrototypeOffset)); } else { // The prototype is in old space; load it directly. mov(reg, Operand(Handle(prototype))); } // Go to the next object in the prototype chain. object = prototype; } // Check the holder map. ldr(scratch, FieldMemOperand(reg, HeapObject::kMapOffset)); cmp(scratch, Operand(Handle(object->map()))); b(ne, miss); // Log the check depth. LOG(IntEvent("check-maps-depth", depth)); // Perform security check for access to the global object and return // the holder register. ASSERT(object == holder); ASSERT(object->IsJSGlobalProxy() || !object->IsAccessCheckNeeded()); if (object->IsJSGlobalProxy()) { CheckAccessGlobalProxy(reg, scratch, miss); } return reg; } void MacroAssembler::CheckAccessGlobalProxy(Register holder_reg, Register scratch, Label* miss) { Label same_contexts; ASSERT(!holder_reg.is(scratch)); ASSERT(!holder_reg.is(ip)); ASSERT(!scratch.is(ip)); // Load current lexical context from the stack frame. ldr(scratch, MemOperand(fp, StandardFrameConstants::kContextOffset)); // In debug mode, make sure the lexical context is set. #ifdef DEBUG cmp(scratch, Operand(0)); Check(ne, "we should not have an empty lexical context"); #endif // Load the global context of the current context. int offset = Context::kHeaderSize + Context::GLOBAL_INDEX * kPointerSize; ldr(scratch, FieldMemOperand(scratch, offset)); ldr(scratch, FieldMemOperand(scratch, GlobalObject::kGlobalContextOffset)); // Check the context is a global context. if (FLAG_debug_code) { // TODO(119): avoid push(holder_reg)/pop(holder_reg) // Cannot use ip as a temporary in this verification code. Due to the fact // that ip is clobbered as part of cmp with an object Operand. push(holder_reg); // Temporarily save holder on the stack. // Read the first word and compare to the global_context_map. ldr(holder_reg, FieldMemOperand(scratch, HeapObject::kMapOffset)); cmp(holder_reg, Operand(Factory::global_context_map())); Check(eq, "JSGlobalObject::global_context should be a global context."); pop(holder_reg); // Restore holder. } // Check if both contexts are the same. ldr(ip, FieldMemOperand(holder_reg, JSGlobalProxy::kContextOffset)); cmp(scratch, Operand(ip)); b(eq, &same_contexts); // Check the context is a global context. if (FLAG_debug_code) { // TODO(119): avoid push(holder_reg)/pop(holder_reg) // Cannot use ip as a temporary in this verification code. Due to the fact // that ip is clobbered as part of cmp with an object Operand. push(holder_reg); // Temporarily save holder on the stack. mov(holder_reg, ip); // Move ip to its holding place. cmp(holder_reg, Operand(Factory::null_value())); Check(ne, "JSGlobalProxy::context() should not be null."); ldr(holder_reg, FieldMemOperand(holder_reg, HeapObject::kMapOffset)); cmp(holder_reg, Operand(Factory::global_context_map())); Check(eq, "JSGlobalObject::global_context should be a global context."); // Restore ip is not needed. ip is reloaded below. pop(holder_reg); // Restore holder. // Restore ip to holder's context. ldr(ip, FieldMemOperand(holder_reg, JSGlobalProxy::kContextOffset)); } // Check that the security token in the calling global object is // compatible with the security token in the receiving global // object. int token_offset = Context::kHeaderSize + Context::SECURITY_TOKEN_INDEX * kPointerSize; ldr(scratch, FieldMemOperand(scratch, token_offset)); ldr(ip, FieldMemOperand(ip, token_offset)); cmp(scratch, Operand(ip)); b(ne, miss); bind(&same_contexts); } void MacroAssembler::CallStub(CodeStub* stub) { ASSERT(allow_stub_calls()); // stub calls are not allowed in some stubs Call(stub->GetCode(), RelocInfo::CODE_TARGET); } void MacroAssembler::StubReturn(int argc) { ASSERT(argc >= 1 && generating_stub()); if (argc > 1) add(sp, sp, Operand((argc - 1) * kPointerSize)); Ret(); } void MacroAssembler::IllegalOperation(int num_arguments) { if (num_arguments > 0) { add(sp, sp, Operand(num_arguments * kPointerSize)); } mov(r0, Operand(Factory::undefined_value())); } void MacroAssembler::CallRuntime(Runtime::Function* f, int num_arguments) { // All parameters are on the stack. r0 has the return value after call. // If the expected number of arguments of the runtime function is // constant, we check that the actual number of arguments match the // expectation. if (f->nargs >= 0 && f->nargs != num_arguments) { IllegalOperation(num_arguments); return; } Runtime::FunctionId function_id = static_cast(f->stub_id); RuntimeStub stub(function_id, num_arguments); CallStub(&stub); } void MacroAssembler::CallRuntime(Runtime::FunctionId fid, int num_arguments) { CallRuntime(Runtime::FunctionForId(fid), num_arguments); } void MacroAssembler::TailCallRuntime(const ExternalReference& ext, int num_arguments) { // TODO(1236192): Most runtime routines don't need the number of // arguments passed in because it is constant. At some point we // should remove this need and make the runtime routine entry code // smarter. mov(r0, Operand(num_arguments)); JumpToBuiltin(ext); } void MacroAssembler::JumpToBuiltin(const ExternalReference& builtin) { #if defined(__thumb__) // Thumb mode builtin. ASSERT((reinterpret_cast(builtin.address()) & 1) == 1); #endif mov(r1, Operand(builtin)); CEntryStub stub; Jump(stub.GetCode(), RelocInfo::CODE_TARGET); } Handle MacroAssembler::ResolveBuiltin(Builtins::JavaScript id, bool* resolved) { // Contract with compiled functions is that the function is passed in r1. int builtins_offset = JSBuiltinsObject::kJSBuiltinsOffset + (id * kPointerSize); ldr(r1, MemOperand(cp, Context::SlotOffset(Context::GLOBAL_INDEX))); ldr(r1, FieldMemOperand(r1, GlobalObject::kBuiltinsOffset)); ldr(r1, FieldMemOperand(r1, builtins_offset)); return Builtins::GetCode(id, resolved); } void MacroAssembler::InvokeBuiltin(Builtins::JavaScript id, InvokeJSFlags flags) { bool resolved; Handle code = ResolveBuiltin(id, &resolved); if (flags == CALL_JS) { Call(code, RelocInfo::CODE_TARGET); } else { ASSERT(flags == JUMP_JS); Jump(code, RelocInfo::CODE_TARGET); } if (!resolved) { const char* name = Builtins::GetName(id); int argc = Builtins::GetArgumentsCount(id); uint32_t flags = Bootstrapper::FixupFlagsArgumentsCount::encode(argc) | Bootstrapper::FixupFlagsIsPCRelative::encode(true) | Bootstrapper::FixupFlagsUseCodeObject::encode(false); Unresolved entry = { pc_offset() - sizeof(Instr), flags, name }; unresolved_.Add(entry); } } void MacroAssembler::GetBuiltinEntry(Register target, Builtins::JavaScript id) { bool resolved; Handle code = ResolveBuiltin(id, &resolved); mov(target, Operand(code)); if (!resolved) { const char* name = Builtins::GetName(id); int argc = Builtins::GetArgumentsCount(id); uint32_t flags = Bootstrapper::FixupFlagsArgumentsCount::encode(argc) | Bootstrapper::FixupFlagsIsPCRelative::encode(true) | Bootstrapper::FixupFlagsUseCodeObject::encode(true); Unresolved entry = { pc_offset() - sizeof(Instr), flags, name }; unresolved_.Add(entry); } add(target, target, Operand(Code::kHeaderSize - kHeapObjectTag)); } void MacroAssembler::SetCounter(StatsCounter* counter, int value, Register scratch1, Register scratch2) { if (FLAG_native_code_counters && counter->Enabled()) { mov(scratch1, Operand(value)); mov(scratch2, Operand(ExternalReference(counter))); str(scratch1, MemOperand(scratch2)); } } void MacroAssembler::IncrementCounter(StatsCounter* counter, int value, Register scratch1, Register scratch2) { ASSERT(value > 0); if (FLAG_native_code_counters && counter->Enabled()) { mov(scratch2, Operand(ExternalReference(counter))); ldr(scratch1, MemOperand(scratch2)); add(scratch1, scratch1, Operand(value)); str(scratch1, MemOperand(scratch2)); } } void MacroAssembler::DecrementCounter(StatsCounter* counter, int value, Register scratch1, Register scratch2) { ASSERT(value > 0); if (FLAG_native_code_counters && counter->Enabled()) { mov(scratch2, Operand(ExternalReference(counter))); ldr(scratch1, MemOperand(scratch2)); sub(scratch1, scratch1, Operand(value)); str(scratch1, MemOperand(scratch2)); } } void MacroAssembler::Assert(Condition cc, const char* msg) { if (FLAG_debug_code) Check(cc, msg); } void MacroAssembler::Check(Condition cc, const char* msg) { Label L; b(cc, &L); Abort(msg); // will not return here bind(&L); } void MacroAssembler::Abort(const char* msg) { // We want to pass the msg string like a smi to avoid GC // problems, however msg is not guaranteed to be aligned // properly. Instead, we pass an aligned pointer that is // a proper v8 smi, but also pass the alignment difference // from the real pointer as a smi. intptr_t p1 = reinterpret_cast(msg); intptr_t p0 = (p1 & ~kSmiTagMask) + kSmiTag; ASSERT(reinterpret_cast(p0)->IsSmi()); #ifdef DEBUG if (msg != NULL) { RecordComment("Abort message: "); RecordComment(msg); } #endif mov(r0, Operand(p0)); push(r0); mov(r0, Operand(Smi::FromInt(p1 - p0))); push(r0); CallRuntime(Runtime::kAbort, 2); // will not return here } } } // namespace v8::internal