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Diffstat (limited to 'js/src/jit/arm/Trampoline-arm.cpp')
| -rw-r--r-- | js/src/jit/arm/Trampoline-arm.cpp | 1442 |
1 files changed, 1442 insertions, 0 deletions
diff --git a/js/src/jit/arm/Trampoline-arm.cpp b/js/src/jit/arm/Trampoline-arm.cpp new file mode 100644 index 0000000000..44144763c9 --- /dev/null +++ b/js/src/jit/arm/Trampoline-arm.cpp @@ -0,0 +1,1442 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- + * vim: set ts=8 sts=4 et sw=4 tw=99: + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "jscompartment.h" + +#include "jit/arm/SharedICHelpers-arm.h" +#include "jit/Bailouts.h" +#include "jit/JitCompartment.h" +#include "jit/JitFrames.h" +#include "jit/JitSpewer.h" +#include "jit/Linker.h" +#ifdef JS_ION_PERF +# include "jit/PerfSpewer.h" +#endif +#include "jit/VMFunctions.h" + +#include "jit/MacroAssembler-inl.h" + +using namespace js; +using namespace js::jit; + +static const FloatRegisterSet NonVolatileFloatRegs = + FloatRegisterSet((1ULL << FloatRegisters::d8) | + (1ULL << FloatRegisters::d9) | + (1ULL << FloatRegisters::d10) | + (1ULL << FloatRegisters::d11) | + (1ULL << FloatRegisters::d12) | + (1ULL << FloatRegisters::d13) | + (1ULL << FloatRegisters::d14) | + (1ULL << FloatRegisters::d15)); + +static void +GenerateReturn(MacroAssembler& masm, int returnCode, SPSProfiler* prof) +{ + // Restore non-volatile floating point registers. + masm.transferMultipleByRuns(NonVolatileFloatRegs, IsLoad, StackPointer, IA); + + // Get rid of padding word. + masm.addPtr(Imm32(sizeof(void*)), sp); + + // Set up return value + masm.ma_mov(Imm32(returnCode), r0); + + // Pop and return + masm.startDataTransferM(IsLoad, sp, IA, WriteBack); + masm.transferReg(r4); + masm.transferReg(r5); + masm.transferReg(r6); + masm.transferReg(r7); + masm.transferReg(r8); + masm.transferReg(r9); + masm.transferReg(r10); + masm.transferReg(r11); + // r12 isn't saved, so it shouldn't be restored. + masm.transferReg(pc); + masm.finishDataTransfer(); + masm.flushBuffer(); +} + +struct EnterJITStack +{ + double d8; + double d9; + double d10; + double d11; + double d12; + double d13; + double d14; + double d15; + + // Padding. + void* padding; + + // Non-volatile registers. + void* r4; + void* r5; + void* r6; + void* r7; + void* r8; + void* r9; + void* r10; + void* r11; + // The abi does not expect r12 (ip) to be preserved + void* lr; + + // Arguments. + // code == r0 + // argc == r1 + // argv == r2 + // frame == r3 + CalleeToken token; + JSObject* scopeChain; + size_t numStackValues; + Value* vp; +}; + +/* + * This method generates a trampoline for a c++ function with the following + * signature: + * void enter(void* code, int argc, Value* argv, InterpreterFrame* fp, CalleeToken + * calleeToken, JSObject* scopeChain, Value* vp) + * ...using standard EABI calling convention + */ +JitCode* +JitRuntime::generateEnterJIT(JSContext* cx, EnterJitType type) +{ + const Address slot_token(sp, offsetof(EnterJITStack, token)); + const Address slot_vp(sp, offsetof(EnterJITStack, vp)); + + MOZ_ASSERT(OsrFrameReg == r3); + + MacroAssembler masm(cx); + Assembler* aasm = &masm; + + // Save non-volatile registers. These must be saved by the trampoline, + // rather than the JIT'd code, because they are scanned by the conservative + // scanner. + masm.startDataTransferM(IsStore, sp, DB, WriteBack); + masm.transferReg(r4); // [sp,0] + masm.transferReg(r5); // [sp,4] + masm.transferReg(r6); // [sp,8] + masm.transferReg(r7); // [sp,12] + masm.transferReg(r8); // [sp,16] + masm.transferReg(r9); // [sp,20] + masm.transferReg(r10); // [sp,24] + masm.transferReg(r11); // [sp,28] + // The abi does not expect r12 (ip) to be preserved + masm.transferReg(lr); // [sp,32] + // The 5th argument is located at [sp, 36] + masm.finishDataTransfer(); + + // Add padding word. + masm.subPtr(Imm32(sizeof(void*)), sp); + + // Push the float registers. + masm.transferMultipleByRuns(NonVolatileFloatRegs, IsStore, sp, DB); + + // Save stack pointer into r8 + masm.movePtr(sp, r8); + + // Load calleeToken into r9. + masm.loadPtr(slot_token, r9); + + // Save stack pointer. + if (type == EnterJitBaseline) + masm.movePtr(sp, r11); + + // Load the number of actual arguments into r10. + masm.loadPtr(slot_vp, r10); + masm.unboxInt32(Address(r10, 0), r10); + + { + Label noNewTarget; + masm.branchTest32(Assembler::Zero, r9, Imm32(CalleeToken_FunctionConstructing), + &noNewTarget); + + masm.add32(Imm32(1), r1); + + masm.bind(&noNewTarget); + } + + // Guarantee stack alignment of Jit frames. + // + // This code moves the stack pointer to the location where it should be when + // we enter the Jit frame. It moves the stack pointer such that we have + // enough space reserved for pushing the arguments, and the JitFrameLayout. + // The stack pointer is also aligned on the alignment expected by the Jit + // frames. + // + // At the end the register r4, is a pointer to the stack where the first + // argument is expected by the Jit frame. + // + aasm->as_sub(r4, sp, O2RegImmShift(r1, LSL, 3)); // r4 = sp - argc*8 + aasm->as_bic(r4, r4, Imm8(JitStackAlignment - 1)); + // r4 is now the aligned on the bottom of the list of arguments. + static_assert(sizeof(JitFrameLayout) % JitStackAlignment == 0, + "No need to consider the JitFrameLayout for aligning the stack"); + // sp' = ~(JitStackAlignment - 1) & (sp - argc * sizeof(Value)) - sizeof(JitFrameLayout) + aasm->as_sub(sp, r4, Imm8(sizeof(JitFrameLayout))); + + // Get a copy of the number of args to use as a decrement counter, also set + // the zero condition code. + aasm->as_mov(r5, O2Reg(r1), SetCC); + + // Loop over arguments, copying them from an unknown buffer onto the Ion + // stack so they can be accessed from JIT'ed code. + { + Label header, footer; + // If there aren't any arguments, don't do anything. + aasm->as_b(&footer, Assembler::Zero); + // Get the top of the loop. + masm.bind(&header); + aasm->as_sub(r5, r5, Imm8(1), SetCC); + // We could be more awesome, and unroll this, using a loadm + // (particularly since the offset is effectively 0) but that seems more + // error prone, and complex. + // BIG FAT WARNING: this loads both r6 and r7. + aasm->as_extdtr(IsLoad, 64, true, PostIndex, r6, EDtrAddr(r2, EDtrOffImm(8))); + aasm->as_extdtr(IsStore, 64, true, PostIndex, r6, EDtrAddr(r4, EDtrOffImm(8))); + aasm->as_b(&header, Assembler::NonZero); + masm.bind(&footer); + } + + masm.ma_sub(r8, sp, r8); + masm.makeFrameDescriptor(r8, JitFrame_Entry, JitFrameLayout::Size()); + + masm.startDataTransferM(IsStore, sp, IB, NoWriteBack); + // [sp] = return address (written later) + masm.transferReg(r8); // [sp',4] = descriptor, argc*8+20 + masm.transferReg(r9); // [sp',8] = callee token + masm.transferReg(r10); // [sp',12] = actual arguments + masm.finishDataTransfer(); + + Label returnLabel; + if (type == EnterJitBaseline) { + // Handle OSR. + AllocatableGeneralRegisterSet regs(GeneralRegisterSet::All()); + regs.take(JSReturnOperand); + regs.takeUnchecked(OsrFrameReg); + regs.take(r11); + regs.take(ReturnReg); + + const Address slot_numStackValues(r11, offsetof(EnterJITStack, numStackValues)); + + Label notOsr; + masm.branchTestPtr(Assembler::Zero, OsrFrameReg, OsrFrameReg, ¬Osr); + + Register scratch = regs.takeAny(); + + Register numStackValues = regs.takeAny(); + masm.load32(slot_numStackValues, numStackValues); + + // Write return address. On ARM, CodeLabel is only used for tableswitch, + // so we can't use it here to get the return address. Instead, we use pc + // + a fixed offset to a jump to returnLabel. The pc register holds pc + + // 8, so we add the size of 2 instructions to skip the instructions + // emitted by storePtr and jump(&skipJump). + { + AutoForbidPools afp(&masm, 5); + Label skipJump; + masm.mov(pc, scratch); + masm.addPtr(Imm32(2 * sizeof(uint32_t)), scratch); + masm.storePtr(scratch, Address(sp, 0)); + masm.jump(&skipJump); + masm.jump(&returnLabel); + masm.bind(&skipJump); + } + + // Push previous frame pointer. + masm.push(r11); + + // Reserve frame. + Register framePtr = r11; + masm.subPtr(Imm32(BaselineFrame::Size()), sp); + masm.mov(sp, framePtr); + +#ifdef XP_WIN + // Can't push large frames blindly on windows. Touch frame memory + // incrementally. + masm.ma_lsl(Imm32(3), numStackValues, scratch); + masm.subPtr(scratch, framePtr); + { + masm.ma_sub(sp, Imm32(WINDOWS_BIG_FRAME_TOUCH_INCREMENT), scratch); + + Label touchFrameLoop; + Label touchFrameLoopEnd; + masm.bind(&touchFrameLoop); + masm.branchPtr(Assembler::Below, scratch, framePtr, &touchFrameLoopEnd); + masm.store32(Imm32(0), Address(scratch, 0)); + masm.subPtr(Imm32(WINDOWS_BIG_FRAME_TOUCH_INCREMENT), scratch); + masm.jump(&touchFrameLoop); + masm.bind(&touchFrameLoopEnd); + } + masm.mov(sp, framePtr); +#endif + + // Reserve space for locals and stack values. + masm.ma_lsl(Imm32(3), numStackValues, scratch); + masm.ma_sub(sp, scratch, sp); + + // Enter exit frame. + masm.addPtr(Imm32(BaselineFrame::Size() + BaselineFrame::FramePointerOffset), scratch); + masm.makeFrameDescriptor(scratch, JitFrame_BaselineJS, ExitFrameLayout::Size()); + masm.push(scratch); + masm.push(Imm32(0)); // Fake return address. + // No GC things to mark on the stack, push a bare token. + masm.enterFakeExitFrame(ExitFrameLayoutBareToken); + + masm.push(framePtr); // BaselineFrame + masm.push(r0); // jitcode + + masm.setupUnalignedABICall(scratch); + masm.passABIArg(r11); // BaselineFrame + masm.passABIArg(OsrFrameReg); // InterpreterFrame + masm.passABIArg(numStackValues); + masm.callWithABI(JS_FUNC_TO_DATA_PTR(void*, jit::InitBaselineFrameForOsr)); + + Register jitcode = regs.takeAny(); + masm.pop(jitcode); + masm.pop(framePtr); + + MOZ_ASSERT(jitcode != ReturnReg); + + Label error; + masm.addPtr(Imm32(ExitFrameLayout::SizeWithFooter()), sp); + masm.addPtr(Imm32(BaselineFrame::Size()), framePtr); + masm.branchIfFalseBool(ReturnReg, &error); + + // If OSR-ing, then emit instrumentation for setting lastProfilerFrame + // if profiler instrumentation is enabled. + { + Label skipProfilingInstrumentation; + Register realFramePtr = numStackValues; + AbsoluteAddress addressOfEnabled(cx->runtime()->spsProfiler.addressOfEnabled()); + masm.branch32(Assembler::Equal, addressOfEnabled, Imm32(0), + &skipProfilingInstrumentation); + masm.as_add(realFramePtr, framePtr, Imm8(sizeof(void*))); + masm.profilerEnterFrame(realFramePtr, scratch); + masm.bind(&skipProfilingInstrumentation); + } + + masm.jump(jitcode); + + // OOM: Load error value, discard return address and previous frame + // pointer and return. + masm.bind(&error); + masm.mov(framePtr, sp); + masm.addPtr(Imm32(2 * sizeof(uintptr_t)), sp); + masm.moveValue(MagicValue(JS_ION_ERROR), JSReturnOperand); + masm.jump(&returnLabel); + + masm.bind(¬Osr); + // Load the scope chain in R1. + MOZ_ASSERT(R1.scratchReg() != r0); + masm.loadPtr(Address(r11, offsetof(EnterJITStack, scopeChain)), R1.scratchReg()); + } + + // The Data transfer is pushing 4 words, which already account for the + // return address space of the Jit frame. We have to undo what the data + // transfer did before making the call. + masm.addPtr(Imm32(sizeof(uintptr_t)), sp); + + // The callee will push the return address on the stack, thus we check that + // the stack would be aligned once the call is complete. + masm.assertStackAlignment(JitStackAlignment, sizeof(uintptr_t)); + + // Call the function. + masm.callJitNoProfiler(r0); + + if (type == EnterJitBaseline) { + // Baseline OSR will return here. + masm.bind(&returnLabel); + } + + // The top of the stack now points to the address of the field following the + // return address because the return address is popped for the return, so we + // need to remove the size of the return address field. + aasm->as_sub(sp, sp, Imm8(4)); + + // Load off of the stack the size of our local stack. + masm.loadPtr(Address(sp, JitFrameLayout::offsetOfDescriptor()), r5); + aasm->as_add(sp, sp, lsr(r5, FRAMESIZE_SHIFT)); + + // Store the returned value into the slot_vp + masm.loadPtr(slot_vp, r5); + masm.storeValue(JSReturnOperand, Address(r5, 0)); + + // :TODO: Optimize storeValue with: + // We're using a load-double here. In order for that to work, the data needs + // to be stored in two consecutive registers, make sure this is the case + // MOZ_ASSERT(JSReturnReg_Type.code() == JSReturnReg_Data.code()+1); + // aasm->as_extdtr(IsStore, 64, true, Offset, + // JSReturnReg_Data, EDtrAddr(r5, EDtrOffImm(0))); + + // Restore non-volatile registers and return. + GenerateReturn(masm, true, &cx->runtime()->spsProfiler); + + Linker linker(masm); + AutoFlushICache afc("EnterJIT"); + JitCode* code = linker.newCode<NoGC>(cx, OTHER_CODE); + +#ifdef JS_ION_PERF + writePerfSpewerJitCodeProfile(code, "EnterJIT"); +#endif + + return code; +} + +JitCode* +JitRuntime::generateInvalidator(JSContext* cx) +{ + // See large comment in x86's JitRuntime::generateInvalidator. + MacroAssembler masm(cx); + // At this point, one of two things has happened: + // 1) Execution has just returned from C code, which left the stack aligned + // 2) Execution has just returned from Ion code, which left the stack unaligned. + // The old return address should not matter, but we still want the stack to + // be aligned, and there is no good reason to automatically align it with a + // call to setupUnalignedABICall. + masm.as_bic(sp, sp, Imm8(7)); + masm.startDataTransferM(IsStore, sp, DB, WriteBack); + // We don't have to push everything, but this is likely easier. + // Setting regs_. + for (uint32_t i = 0; i < Registers::Total; i++) + masm.transferReg(Register::FromCode(i)); + masm.finishDataTransfer(); + + // Since our datastructures for stack inspection are compile-time fixed, + // if there are only 16 double registers, then we need to reserve + // space on the stack for the missing 16. + if (FloatRegisters::ActualTotalPhys() != FloatRegisters::TotalPhys) { + ScratchRegisterScope scratch(masm); + int missingRegs = FloatRegisters::TotalPhys - FloatRegisters::ActualTotalPhys(); + masm.ma_sub(Imm32(missingRegs * sizeof(double)), sp, scratch); + } + + masm.startFloatTransferM(IsStore, sp, DB, WriteBack); + for (uint32_t i = 0; i < FloatRegisters::ActualTotalPhys(); i++) + masm.transferFloatReg(FloatRegister(i, FloatRegister::Double)); + masm.finishFloatTransfer(); + + masm.ma_mov(sp, r0); + const int sizeOfRetval = sizeof(size_t)*2; + masm.reserveStack(sizeOfRetval); + masm.mov(sp, r1); + const int sizeOfBailoutInfo = sizeof(void*)*2; + masm.reserveStack(sizeOfBailoutInfo); + masm.mov(sp, r2); + masm.setupAlignedABICall(); + masm.passABIArg(r0); + masm.passABIArg(r1); + masm.passABIArg(r2); + masm.callWithABI(JS_FUNC_TO_DATA_PTR(void*, InvalidationBailout)); + + masm.ma_ldr(DTRAddr(sp, DtrOffImm(0)), r2); + { + ScratchRegisterScope scratch(masm); + masm.ma_ldr(Address(sp, sizeOfBailoutInfo), r1, scratch); + } + // Remove the return address, the IonScript, the register state + // (InvaliationBailoutStack) and the space that was allocated for the return + // value. + { + ScratchRegisterScope scratch(masm); + masm.ma_add(sp, Imm32(sizeof(InvalidationBailoutStack) + sizeOfRetval + sizeOfBailoutInfo), sp, scratch); + } + // Remove the space that this frame was using before the bailout (computed + // by InvalidationBailout) + masm.ma_add(sp, r1, sp); + + // Jump to shared bailout tail. The BailoutInfo pointer has to be in r2. + JitCode* bailoutTail = cx->runtime()->jitRuntime()->getBailoutTail(); + masm.branch(bailoutTail); + + Linker linker(masm); + AutoFlushICache afc("Invalidator"); + JitCode* code = linker.newCode<NoGC>(cx, OTHER_CODE); + JitSpew(JitSpew_IonInvalidate, " invalidation thunk created at %p", (void*) code->raw()); + +#ifdef JS_ION_PERF + writePerfSpewerJitCodeProfile(code, "Invalidator"); +#endif + + return code; +} + +JitCode* +JitRuntime::generateArgumentsRectifier(JSContext* cx, void** returnAddrOut) +{ + MacroAssembler masm(cx); + masm.pushReturnAddress(); + + // ArgumentsRectifierReg contains the |nargs| pushed onto the current frame. + // Including |this|, there are (|nargs| + 1) arguments to copy. + MOZ_ASSERT(ArgumentsRectifierReg == r8); + + // Copy number of actual arguments into r0. + masm.ma_ldr(DTRAddr(sp, DtrOffImm(RectifierFrameLayout::offsetOfNumActualArgs())), r0); + + // Load the number of |undefined|s to push into r6. + masm.ma_ldr(DTRAddr(sp, DtrOffImm(RectifierFrameLayout::offsetOfCalleeToken())), r1); + { + ScratchRegisterScope scratch(masm); + masm.ma_and(Imm32(CalleeTokenMask), r1, r6, scratch); + } + masm.ma_ldrh(EDtrAddr(r6, EDtrOffImm(JSFunction::offsetOfNargs())), r6); + + masm.ma_sub(r6, r8, r2); + + // Get the topmost argument. + { + ScratchRegisterScope scratch(masm); + masm.ma_alu(sp, lsl(r8, 3), r3, OpAdd); // r3 <- r3 + nargs * 8 + masm.ma_add(r3, Imm32(sizeof(RectifierFrameLayout)), r3, scratch); + } + + { + Label notConstructing; + + masm.branchTest32(Assembler::Zero, r1, Imm32(CalleeToken_FunctionConstructing), + ¬Constructing); + + // Add sizeof(Value) to overcome |this| + masm.as_extdtr(IsLoad, 64, true, Offset, r4, EDtrAddr(r3, EDtrOffImm(8))); + masm.as_extdtr(IsStore, 64, true, PreIndex, r4, EDtrAddr(sp, EDtrOffImm(-8))); + + // Include the newly pushed newTarget value in the frame size + // calculated below. + masm.add32(Imm32(1), r6); + + masm.bind(¬Constructing); + } + + // Push undefined. + masm.moveValue(UndefinedValue(), r5, r4); + { + Label undefLoopTop; + masm.bind(&undefLoopTop); + masm.as_extdtr(IsStore, 64, true, PreIndex, r4, EDtrAddr(sp, EDtrOffImm(-8))); + masm.as_sub(r2, r2, Imm8(1), SetCC); + + masm.ma_b(&undefLoopTop, Assembler::NonZero); + } + + // Push arguments, |nargs| + 1 times (to include |this|). + { + Label copyLoopTop; + masm.bind(©LoopTop); + masm.as_extdtr(IsLoad, 64, true, PostIndex, r4, EDtrAddr(r3, EDtrOffImm(-8))); + masm.as_extdtr(IsStore, 64, true, PreIndex, r4, EDtrAddr(sp, EDtrOffImm(-8))); + + masm.as_sub(r8, r8, Imm8(1), SetCC); + masm.ma_b(©LoopTop, Assembler::NotSigned); + } + + // translate the framesize from values into bytes + masm.as_add(r6, r6, Imm8(1)); + masm.ma_lsl(Imm32(3), r6, r6); + + // Construct sizeDescriptor. + masm.makeFrameDescriptor(r6, JitFrame_Rectifier, JitFrameLayout::Size()); + + // Construct JitFrameLayout. + masm.ma_push(r0); // actual arguments. + masm.ma_push(r1); // callee token + masm.ma_push(r6); // frame descriptor. + + // Call the target function. + // Note that this code assumes the function is JITted. + masm.andPtr(Imm32(CalleeTokenMask), r1); + masm.ma_ldr(DTRAddr(r1, DtrOffImm(JSFunction::offsetOfNativeOrScript())), r3); + masm.loadBaselineOrIonRaw(r3, r3, nullptr); + uint32_t returnOffset = masm.callJitNoProfiler(r3); + + // arg1 + // ... + // argN + // num actual args + // callee token + // sizeDescriptor <- sp now + // return address + + // Remove the rectifier frame. + { + ScratchRegisterScope scratch(masm); + masm.ma_dtr(IsLoad, sp, Imm32(12), r4, scratch, PostIndex); + } + + // arg1 + // ... + // argN <- sp now; r4 <- frame descriptor + // num actual args + // callee token + // sizeDescriptor + // return address + + // Discard pushed arguments. + masm.ma_alu(sp, lsr(r4, FRAMESIZE_SHIFT), sp, OpAdd); + + masm.ret(); + Linker linker(masm); + AutoFlushICache afc("ArgumentsRectifier"); + JitCode* code = linker.newCode<NoGC>(cx, OTHER_CODE); + + if (returnAddrOut) + *returnAddrOut = (void*) (code->raw() + returnOffset); + +#ifdef JS_ION_PERF + writePerfSpewerJitCodeProfile(code, "ArgumentsRectifier"); +#endif + + return code; +} + +static void +PushBailoutFrame(MacroAssembler& masm, uint32_t frameClass, Register spArg) +{ + // the stack should look like: + // [IonFrame] + // bailoutFrame.registersnapshot + // bailoutFrame.fpsnapshot + // bailoutFrame.snapshotOffset + // bailoutFrame.frameSize + + // STEP 1a: Save our register sets to the stack so Bailout() can read + // everything. + // sp % 8 == 0 + + masm.startDataTransferM(IsStore, sp, DB, WriteBack); + // We don't have to push everything, but this is likely easier. + // Setting regs_. + for (uint32_t i = 0; i < Registers::Total; i++) + masm.transferReg(Register::FromCode(i)); + masm.finishDataTransfer(); + + ScratchRegisterScope scratch(masm); + + // Since our datastructures for stack inspection are compile-time fixed, + // if there are only 16 double registers, then we need to reserve + // space on the stack for the missing 16. + if (FloatRegisters::ActualTotalPhys() != FloatRegisters::TotalPhys) { + int missingRegs = FloatRegisters::TotalPhys - FloatRegisters::ActualTotalPhys(); + masm.ma_sub(Imm32(missingRegs * sizeof(double)), sp, scratch); + } + masm.startFloatTransferM(IsStore, sp, DB, WriteBack); + for (uint32_t i = 0; i < FloatRegisters::ActualTotalPhys(); i++) + masm.transferFloatReg(FloatRegister(i, FloatRegister::Double)); + masm.finishFloatTransfer(); + + // STEP 1b: Push both the "return address" of the function call (the address + // of the instruction after the call that we used to get here) as + // well as the callee token onto the stack. The return address is + // currently in r14. We will proceed by loading the callee token + // into a sacrificial register <= r14, then pushing both onto the + // stack. + + // Now place the frameClass onto the stack, via a register. + masm.ma_mov(Imm32(frameClass), r4); + // And onto the stack. Since the stack is full, we need to put this one past + // the end of the current stack. Sadly, the ABI says that we need to always + // point to the lowest place that has been written. The OS is free to do + // whatever it wants below sp. + masm.startDataTransferM(IsStore, sp, DB, WriteBack); + // Set frameClassId_. + masm.transferReg(r4); + // Set tableOffset_; higher registers are stored at higher locations on the + // stack. + masm.transferReg(lr); + masm.finishDataTransfer(); + + masm.ma_mov(sp, spArg); +} + +static void +GenerateBailoutThunk(JSContext* cx, MacroAssembler& masm, uint32_t frameClass) +{ + PushBailoutFrame(masm, frameClass, r0); + + // SP % 8 == 4 + // STEP 1c: Call the bailout function, giving a pointer to the + // structure we just blitted onto the stack. + const int sizeOfBailoutInfo = sizeof(void*)*2; + masm.reserveStack(sizeOfBailoutInfo); + masm.mov(sp, r1); + masm.setupAlignedABICall(); + + // Decrement sp by another 4, so we keep alignment. Not Anymore! Pushing + // both the snapshotoffset as well as the: masm.as_sub(sp, sp, Imm8(4)); + + // Set the old (4-byte aligned) value of the sp as the first argument. + masm.passABIArg(r0); + masm.passABIArg(r1); + + // Sp % 8 == 0 + masm.callWithABI(JS_FUNC_TO_DATA_PTR(void*, Bailout)); + masm.ma_ldr(DTRAddr(sp, DtrOffImm(0)), r2); + { + ScratchRegisterScope scratch(masm); + masm.ma_add(sp, Imm32(sizeOfBailoutInfo), sp, scratch); + } + + // Common size of a bailout frame. + uint32_t bailoutFrameSize = 0 + + sizeof(void*) // frameClass + + sizeof(RegisterDump); + + if (frameClass == NO_FRAME_SIZE_CLASS_ID) { + // Make sure the bailout frame size fits into the offset for a load. + masm.as_dtr(IsLoad, 32, Offset, + r4, DTRAddr(sp, DtrOffImm(4))); + // Used to be: offsetof(BailoutStack, frameSize_) + // This structure is no longer available to us :( + // We add 12 to the bailoutFrameSize because: + // sizeof(uint32_t) for the tableOffset that was pushed onto the stack + // sizeof(uintptr_t) for the snapshotOffset; + // alignment to round the uintptr_t up to a multiple of 8 bytes. + ScratchRegisterScope scratch(masm); + masm.ma_add(sp, Imm32(bailoutFrameSize+12), sp, scratch); + masm.as_add(sp, sp, O2Reg(r4)); + } else { + ScratchRegisterScope scratch(masm); + uint32_t frameSize = FrameSizeClass::FromClass(frameClass).frameSize(); + masm.ma_add(Imm32(// The frame that was added when we entered the most + // recent function. + frameSize + // The size of the "return address" that was dumped on + // the stack. + + sizeof(void*) + // Everything else that was pushed on the stack. + + bailoutFrameSize) + , sp, scratch); + } + + // Jump to shared bailout tail. The BailoutInfo pointer has to be in r2. + JitCode* bailoutTail = cx->runtime()->jitRuntime()->getBailoutTail(); + masm.branch(bailoutTail); +} + +JitCode* +JitRuntime::generateBailoutTable(JSContext* cx, uint32_t frameClass) +{ + MacroAssembler masm(cx); + + { + // Emit the table without any pools being inserted. + Label bailout; + AutoForbidPools afp(&masm, BAILOUT_TABLE_SIZE); + for (size_t i = 0; i < BAILOUT_TABLE_SIZE; i++) + masm.ma_bl(&bailout); + masm.bind(&bailout); + } + + GenerateBailoutThunk(cx, masm, frameClass); + + Linker linker(masm); + AutoFlushICache afc("BailoutTable"); + JitCode* code = linker.newCode<NoGC>(cx, OTHER_CODE); + +#ifdef JS_ION_PERF + writePerfSpewerJitCodeProfile(code, "BailoutTable"); +#endif + + return code; +} + +JitCode* +JitRuntime::generateBailoutHandler(JSContext* cx) +{ + MacroAssembler masm(cx); + GenerateBailoutThunk(cx, masm, NO_FRAME_SIZE_CLASS_ID); + + Linker linker(masm); + AutoFlushICache afc("BailoutHandler"); + JitCode* code = linker.newCode<NoGC>(cx, OTHER_CODE); + +#ifdef JS_ION_PERF + writePerfSpewerJitCodeProfile(code, "BailoutHandler"); +#endif + + return code; +} + +JitCode* +JitRuntime::generateVMWrapper(JSContext* cx, const VMFunction& f) +{ + MOZ_ASSERT(functionWrappers_); + MOZ_ASSERT(functionWrappers_->initialized()); + VMWrapperMap::AddPtr p = functionWrappers_->lookupForAdd(&f); + if (p) + return p->value(); + + // Generate a separated code for the wrapper. + MacroAssembler masm(cx); + AllocatableGeneralRegisterSet regs(Register::Codes::WrapperMask); + + // Wrapper register set is a superset of Volatile register set. + JS_STATIC_ASSERT((Register::Codes::VolatileMask & ~Register::Codes::WrapperMask) == 0); + + // The context is the first argument; r0 is the first argument register. + Register cxreg = r0; + regs.take(cxreg); + + // Stack is: + // ... frame ... + // +8 [args] + argPadding + // +0 ExitFrame + // + // We're aligned to an exit frame, so link it up. + // If it isn't a tail call, then the return address needs to be saved + if (f.expectTailCall == NonTailCall) + masm.pushReturnAddress(); + + masm.enterExitFrame(&f); + masm.loadJSContext(cxreg); + + // Save the base of the argument set stored on the stack. + Register argsBase = InvalidReg; + if (f.explicitArgs) { + argsBase = r5; + regs.take(argsBase); + ScratchRegisterScope scratch(masm); + masm.ma_add(sp, Imm32(ExitFrameLayout::SizeWithFooter()), argsBase, scratch); + } + + // Reserve space for the outparameter. + Register outReg = InvalidReg; + switch (f.outParam) { + case Type_Value: + outReg = r4; + regs.take(outReg); + masm.reserveStack(sizeof(Value)); + masm.ma_mov(sp, outReg); + break; + + case Type_Handle: + outReg = r4; + regs.take(outReg); + masm.PushEmptyRooted(f.outParamRootType); + masm.ma_mov(sp, outReg); + break; + + case Type_Int32: + case Type_Pointer: + case Type_Bool: + outReg = r4; + regs.take(outReg); + masm.reserveStack(sizeof(int32_t)); + masm.ma_mov(sp, outReg); + break; + + case Type_Double: + outReg = r4; + regs.take(outReg); + masm.reserveStack(sizeof(double)); + masm.ma_mov(sp, outReg); + break; + + default: + MOZ_ASSERT(f.outParam == Type_Void); + break; + } + + if (!generateTLEnterVM(cx, masm, f)) + return nullptr; + + masm.setupUnalignedABICall(regs.getAny()); + masm.passABIArg(cxreg); + + size_t argDisp = 0; + + // Copy any arguments. + for (uint32_t explicitArg = 0; explicitArg < f.explicitArgs; explicitArg++) { + MoveOperand from; + switch (f.argProperties(explicitArg)) { + case VMFunction::WordByValue: + masm.passABIArg(MoveOperand(argsBase, argDisp), MoveOp::GENERAL); + argDisp += sizeof(void*); + break; + case VMFunction::DoubleByValue: + // Values should be passed by reference, not by value, so we assert + // that the argument is a double-precision float. + MOZ_ASSERT(f.argPassedInFloatReg(explicitArg)); + masm.passABIArg(MoveOperand(argsBase, argDisp), MoveOp::DOUBLE); + argDisp += sizeof(double); + break; + case VMFunction::WordByRef: + masm.passABIArg(MoveOperand(argsBase, argDisp, MoveOperand::EFFECTIVE_ADDRESS), MoveOp::GENERAL); + argDisp += sizeof(void*); + break; + case VMFunction::DoubleByRef: + masm.passABIArg(MoveOperand(argsBase, argDisp, MoveOperand::EFFECTIVE_ADDRESS), MoveOp::GENERAL); + argDisp += 2 * sizeof(void*); + break; + } + } + + // Copy the implicit outparam, if any. + if (outReg != InvalidReg) + masm.passABIArg(outReg); + + masm.callWithABI(f.wrapped); + + if (!generateTLExitVM(cx, masm, f)) + return nullptr; + + // Test for failure. + switch (f.failType()) { + case Type_Object: + masm.branchTestPtr(Assembler::Zero, r0, r0, masm.failureLabel()); + break; + case Type_Bool: + masm.branchIfFalseBool(r0, masm.failureLabel()); + break; + default: + MOZ_CRASH("unknown failure kind"); + } + + // Load the outparam and free any allocated stack. + switch (f.outParam) { + case Type_Handle: + masm.popRooted(f.outParamRootType, ReturnReg, JSReturnOperand); + break; + + case Type_Value: + masm.loadValue(Address(sp, 0), JSReturnOperand); + masm.freeStack(sizeof(Value)); + break; + + case Type_Int32: + case Type_Pointer: + masm.load32(Address(sp, 0), ReturnReg); + masm.freeStack(sizeof(int32_t)); + break; + + case Type_Bool: + masm.load8ZeroExtend(Address(sp, 0), ReturnReg); + masm.freeStack(sizeof(int32_t)); + break; + + case Type_Double: + if (cx->runtime()->jitSupportsFloatingPoint) + masm.loadDouble(Address(sp, 0), ReturnDoubleReg); + else + masm.assumeUnreachable("Unable to load into float reg, with no FP support."); + masm.freeStack(sizeof(double)); + break; + + default: + MOZ_ASSERT(f.outParam == Type_Void); + break; + } + masm.leaveExitFrame(); + masm.retn(Imm32(sizeof(ExitFrameLayout) + + f.explicitStackSlots() * sizeof(void*) + + f.extraValuesToPop * sizeof(Value))); + + Linker linker(masm); + AutoFlushICache afc("VMWrapper"); + JitCode* wrapper = linker.newCode<NoGC>(cx, OTHER_CODE); + if (!wrapper) + return nullptr; + + // linker.newCode may trigger a GC and sweep functionWrappers_ so we have to + // use relookupOrAdd instead of add. + if (!functionWrappers_->relookupOrAdd(p, &f, wrapper)) + return nullptr; + +#ifdef JS_ION_PERF + writePerfSpewerJitCodeProfile(wrapper, "VMWrapper"); +#endif + + return wrapper; +} + +JitCode* +JitRuntime::generatePreBarrier(JSContext* cx, MIRType type) +{ + MacroAssembler masm(cx); + + LiveRegisterSet save; + if (cx->runtime()->jitSupportsFloatingPoint) { + save.set() = RegisterSet(GeneralRegisterSet(Registers::VolatileMask), + FloatRegisterSet(FloatRegisters::VolatileDoubleMask)); + } else { + save.set() = RegisterSet(GeneralRegisterSet(Registers::VolatileMask), + FloatRegisterSet()); + } + save.add(lr); + masm.PushRegsInMask(save); + + MOZ_ASSERT(PreBarrierReg == r1); + masm.movePtr(ImmPtr(cx->runtime()), r0); + + masm.setupUnalignedABICall(r2); + masm.passABIArg(r0); + masm.passABIArg(r1); + masm.callWithABI(IonMarkFunction(type)); + save.take(AnyRegister(lr)); + save.add(pc); + masm.PopRegsInMask(save); + + Linker linker(masm); + AutoFlushICache afc("PreBarrier"); + JitCode* code = linker.newCode<NoGC>(cx, OTHER_CODE); + +#ifdef JS_ION_PERF + writePerfSpewerJitCodeProfile(code, "PreBarrier"); +#endif + + return code; +} + +typedef bool (*HandleDebugTrapFn)(JSContext*, BaselineFrame*, uint8_t*, bool*); +static const VMFunction HandleDebugTrapInfo = + FunctionInfo<HandleDebugTrapFn>(HandleDebugTrap, "HandleDebugTrap"); + +JitCode* +JitRuntime::generateDebugTrapHandler(JSContext* cx) +{ + MacroAssembler masm; + + Register scratch1 = r0; + Register scratch2 = r1; + + // Load BaselineFrame pointer in scratch1. + masm.mov(r11, scratch1); + masm.subPtr(Imm32(BaselineFrame::Size()), scratch1); + + // Enter a stub frame and call the HandleDebugTrap VM function. Ensure the + // stub frame has a nullptr ICStub pointer, since this pointer is marked + // during GC. + masm.movePtr(ImmPtr(nullptr), ICStubReg); + EmitBaselineEnterStubFrame(masm, scratch2); + + JitCode* code = cx->runtime()->jitRuntime()->getVMWrapper(HandleDebugTrapInfo); + if (!code) + return nullptr; + + masm.push(lr); + masm.push(scratch1); + EmitBaselineCallVM(code, masm); + + EmitBaselineLeaveStubFrame(masm); + + // If the stub returns |true|, we have to perform a forced return (return + // from the JS frame). If the stub returns |false|, just return from the + // trap stub so that execution continues at the current pc. + Label forcedReturn; + masm.branchTest32(Assembler::NonZero, ReturnReg, ReturnReg, &forcedReturn); + masm.mov(lr, pc); + + masm.bind(&forcedReturn); + masm.loadValue(Address(r11, BaselineFrame::reverseOffsetOfReturnValue()), + JSReturnOperand); + masm.mov(r11, sp); + masm.pop(r11); + + // Before returning, if profiling is turned on, make sure that lastProfilingFrame + // is set to the correct caller frame. + { + Label skipProfilingInstrumentation; + AbsoluteAddress addressOfEnabled(cx->runtime()->spsProfiler.addressOfEnabled()); + masm.branch32(Assembler::Equal, addressOfEnabled, Imm32(0), &skipProfilingInstrumentation); + masm.profilerExitFrame(); + masm.bind(&skipProfilingInstrumentation); + } + + masm.ret(); + + Linker linker(masm); + AutoFlushICache afc("DebugTrapHandler"); + JitCode* codeDbg = linker.newCode<NoGC>(cx, OTHER_CODE); + +#ifdef JS_ION_PERF + writePerfSpewerJitCodeProfile(codeDbg, "DebugTrapHandler"); +#endif + + return codeDbg; +} + +JitCode* +JitRuntime::generateExceptionTailStub(JSContext* cx, void* handler) +{ + MacroAssembler masm; + + masm.handleFailureWithHandlerTail(handler); + + Linker linker(masm); + AutoFlushICache afc("ExceptionTailStub"); + JitCode* code = linker.newCode<NoGC>(cx, OTHER_CODE); + +#ifdef JS_ION_PERF + writePerfSpewerJitCodeProfile(code, "ExceptionTailStub"); +#endif + + return code; +} + +JitCode* +JitRuntime::generateBailoutTailStub(JSContext* cx) +{ + MacroAssembler masm; + + masm.generateBailoutTail(r1, r2); + + Linker linker(masm); + AutoFlushICache afc("BailoutTailStub"); + JitCode* code = linker.newCode<NoGC>(cx, OTHER_CODE); + +#ifdef JS_ION_PERF + writePerfSpewerJitCodeProfile(code, "BailoutTailStub"); +#endif + + return code; +} + +JitCode* +JitRuntime::generateProfilerExitFrameTailStub(JSContext* cx) +{ + MacroAssembler masm; + + Register scratch1 = r5; + Register scratch2 = r6; + Register scratch3 = r7; + Register scratch4 = r8; + + // + // The code generated below expects that the current stack pointer points + // to an Ion or Baseline frame, at the state it would be immediately + // before a ret(). Thus, after this stub's business is done, it executes + // a ret() and returns directly to the caller script, on behalf of the + // callee script that jumped to this code. + // + // Thus the expected stack is: + // + // StackPointer ----+ + // v + // ..., ActualArgc, CalleeToken, Descriptor, ReturnAddr + // MEM-HI MEM-LOW + // + // + // The generated jitcode is responsible for overwriting the + // jitActivation->lastProfilingFrame field with a pointer to the previous + // Ion or Baseline jit-frame that was pushed before this one. It is also + // responsible for overwriting jitActivation->lastProfilingCallSite with + // the return address into that frame. The frame could either be an + // immediate "caller" frame, or it could be a frame in a previous + // JitActivation (if the current frame was entered from C++, and the C++ + // was entered by some caller jit-frame further down the stack). + // + // So this jitcode is responsible for "walking up" the jit stack, finding + // the previous Ion or Baseline JS frame, and storing its address and the + // return address into the appropriate fields on the current jitActivation. + // + // There are a fixed number of different path types that can lead to the + // current frame, which is either a baseline or ion frame: + // + // <Baseline-Or-Ion> + // ^ + // | + // ^--- Ion + // | + // ^--- Baseline Stub <---- Baseline + // | + // ^--- Argument Rectifier + // | ^ + // | | + // | ^--- Ion + // | | + // | ^--- Baseline Stub <---- Baseline + // | + // ^--- Entry Frame (From C++) + // + Register actReg = scratch4; + AbsoluteAddress activationAddr(GetJitContext()->runtime->addressOfProfilingActivation()); + masm.loadPtr(activationAddr, actReg); + + Address lastProfilingFrame(actReg, JitActivation::offsetOfLastProfilingFrame()); + Address lastProfilingCallSite(actReg, JitActivation::offsetOfLastProfilingCallSite()); + +#ifdef DEBUG + // Ensure that frame we are exiting is current lastProfilingFrame + { + masm.loadPtr(lastProfilingFrame, scratch1); + Label checkOk; + masm.branchPtr(Assembler::Equal, scratch1, ImmWord(0), &checkOk); + masm.branchPtr(Assembler::Equal, StackPointer, scratch1, &checkOk); + masm.assumeUnreachable( + "Mismatch between stored lastProfilingFrame and current stack pointer."); + masm.bind(&checkOk); + } +#endif + + // Load the frame descriptor into |scratch1|, figure out what to do depending on its type. + masm.loadPtr(Address(StackPointer, JitFrameLayout::offsetOfDescriptor()), scratch1); + + // Going into the conditionals, we will have: + // FrameDescriptor.size in scratch1 + // FrameDescriptor.type in scratch2 + { + ScratchRegisterScope asmScratch(masm); + masm.ma_and(Imm32((1 << FRAMETYPE_BITS) - 1), scratch1, scratch2, asmScratch); + } + masm.rshiftPtr(Imm32(FRAMESIZE_SHIFT), scratch1); + + // Handling of each case is dependent on FrameDescriptor.type + Label handle_IonJS; + Label handle_BaselineStub; + Label handle_Rectifier; + Label handle_IonAccessorIC; + Label handle_Entry; + Label end; + + masm.branch32(Assembler::Equal, scratch2, Imm32(JitFrame_IonJS), &handle_IonJS); + masm.branch32(Assembler::Equal, scratch2, Imm32(JitFrame_BaselineJS), &handle_IonJS); + masm.branch32(Assembler::Equal, scratch2, Imm32(JitFrame_BaselineStub), &handle_BaselineStub); + masm.branch32(Assembler::Equal, scratch2, Imm32(JitFrame_Rectifier), &handle_Rectifier); + masm.branch32(Assembler::Equal, scratch2, Imm32(JitFrame_IonAccessorIC), &handle_IonAccessorIC); + masm.branch32(Assembler::Equal, scratch2, Imm32(JitFrame_Entry), &handle_Entry); + + masm.assumeUnreachable("Invalid caller frame type when exiting from Ion frame."); + + // + // JitFrame_IonJS + // + // Stack layout: + // ... + // Ion-Descriptor + // Prev-FP ---> Ion-ReturnAddr + // ... previous frame data ... |- Descriptor.Size + // ... arguments ... | + // ActualArgc | + // CalleeToken |- JitFrameLayout::Size() + // Descriptor | + // FP -----> ReturnAddr | + // + masm.bind(&handle_IonJS); + { + // |scratch1| contains Descriptor.size + + // returning directly to an IonJS frame. Store return addr to frame + // in lastProfilingCallSite. + masm.loadPtr(Address(StackPointer, JitFrameLayout::offsetOfReturnAddress()), scratch2); + masm.storePtr(scratch2, lastProfilingCallSite); + + // Store return frame in lastProfilingFrame. + // scratch2 := StackPointer + Descriptor.size*1 + JitFrameLayout::Size(); + masm.ma_add(StackPointer, scratch1, scratch2); + masm.as_add(scratch2, scratch2, Imm8(JitFrameLayout::Size())); + masm.storePtr(scratch2, lastProfilingFrame); + masm.ret(); + } + + // + // JitFrame_BaselineStub + // + // Look past the stub and store the frame pointer to + // the baselineJS frame prior to it. + // + // Stack layout: + // ... + // BL-Descriptor + // Prev-FP ---> BL-ReturnAddr + // +-----> BL-PrevFramePointer + // | ... BL-FrameData ... + // | BLStub-Descriptor + // | BLStub-ReturnAddr + // | BLStub-StubPointer | + // +------ BLStub-SavedFramePointer |- Descriptor.Size + // ... arguments ... | + // ActualArgc | + // CalleeToken |- JitFrameLayout::Size() + // Descriptor | + // FP -----> ReturnAddr | + // + // We take advantage of the fact that the stub frame saves the frame + // pointer pointing to the baseline frame, so a bunch of calculation can + // be avoided. + // + masm.bind(&handle_BaselineStub); + { + masm.ma_add(StackPointer, scratch1, scratch3); + Address stubFrameReturnAddr(scratch3, + JitFrameLayout::Size() + + BaselineStubFrameLayout::offsetOfReturnAddress()); + masm.loadPtr(stubFrameReturnAddr, scratch2); + masm.storePtr(scratch2, lastProfilingCallSite); + + Address stubFrameSavedFramePtr(scratch3, + JitFrameLayout::Size() - (2 * sizeof(void*))); + masm.loadPtr(stubFrameSavedFramePtr, scratch2); + masm.addPtr(Imm32(sizeof(void*)), scratch2); // Skip past BL-PrevFramePtr + masm.storePtr(scratch2, lastProfilingFrame); + masm.ret(); + } + + + // + // JitFrame_Rectifier + // + // The rectifier frame can be preceded by either an IonJS or a + // BaselineStub frame. + // + // Stack layout if caller of rectifier was Ion: + // + // Ion-Descriptor + // Ion-ReturnAddr + // ... ion frame data ... |- Rect-Descriptor.Size + // < COMMON LAYOUT > + // + // Stack layout if caller of rectifier was Baseline: + // + // BL-Descriptor + // Prev-FP ---> BL-ReturnAddr + // +-----> BL-SavedFramePointer + // | ... baseline frame data ... + // | BLStub-Descriptor + // | BLStub-ReturnAddr + // | BLStub-StubPointer | + // +------ BLStub-SavedFramePointer |- Rect-Descriptor.Size + // ... args to rectifier ... | + // < COMMON LAYOUT > + // + // Common stack layout: + // + // ActualArgc | + // CalleeToken |- IonRectitiferFrameLayout::Size() + // Rect-Descriptor | + // Rect-ReturnAddr | + // ... rectifier data & args ... |- Descriptor.Size + // ActualArgc | + // CalleeToken |- JitFrameLayout::Size() + // Descriptor | + // FP -----> ReturnAddr | + // + masm.bind(&handle_Rectifier); + { + // scratch2 := StackPointer + Descriptor.size*1 + JitFrameLayout::Size(); + masm.ma_add(StackPointer, scratch1, scratch2); + masm.add32(Imm32(JitFrameLayout::Size()), scratch2); + masm.loadPtr(Address(scratch2, RectifierFrameLayout::offsetOfDescriptor()), scratch3); + masm.ma_lsr(Imm32(FRAMESIZE_SHIFT), scratch3, scratch1); + masm.and32(Imm32((1 << FRAMETYPE_BITS) - 1), scratch3); + + // Now |scratch1| contains Rect-Descriptor.Size + // and |scratch2| points to Rectifier frame + // and |scratch3| contains Rect-Descriptor.Type + + // Check for either Ion or BaselineStub frame. + Label handle_Rectifier_BaselineStub; + masm.branch32(Assembler::NotEqual, scratch3, Imm32(JitFrame_IonJS), + &handle_Rectifier_BaselineStub); + + // Handle Rectifier <- IonJS + // scratch3 := RectFrame[ReturnAddr] + masm.loadPtr(Address(scratch2, RectifierFrameLayout::offsetOfReturnAddress()), scratch3); + masm.storePtr(scratch3, lastProfilingCallSite); + + // scratch3 := RectFrame + Rect-Descriptor.Size + RectifierFrameLayout::Size() + masm.ma_add(scratch2, scratch1, scratch3); + masm.add32(Imm32(RectifierFrameLayout::Size()), scratch3); + masm.storePtr(scratch3, lastProfilingFrame); + masm.ret(); + + // Handle Rectifier <- BaselineStub <- BaselineJS + masm.bind(&handle_Rectifier_BaselineStub); +#ifdef DEBUG + { + Label checkOk; + masm.branch32(Assembler::Equal, scratch3, Imm32(JitFrame_BaselineStub), &checkOk); + masm.assumeUnreachable("Unrecognized frame preceding baselineStub."); + masm.bind(&checkOk); + } +#endif + masm.ma_add(scratch2, scratch1, scratch3); + Address stubFrameReturnAddr(scratch3, RectifierFrameLayout::Size() + + BaselineStubFrameLayout::offsetOfReturnAddress()); + masm.loadPtr(stubFrameReturnAddr, scratch2); + masm.storePtr(scratch2, lastProfilingCallSite); + + Address stubFrameSavedFramePtr(scratch3, + RectifierFrameLayout::Size() - (2 * sizeof(void*))); + masm.loadPtr(stubFrameSavedFramePtr, scratch2); + masm.addPtr(Imm32(sizeof(void*)), scratch2); + masm.storePtr(scratch2, lastProfilingFrame); + masm.ret(); + } + + // JitFrame_IonAccessorIC + // + // The caller is always an IonJS frame. + // + // Ion-Descriptor + // Ion-ReturnAddr + // ... ion frame data ... |- AccFrame-Descriptor.Size + // StubCode | + // AccFrame-Descriptor |- IonAccessorICFrameLayout::Size() + // AccFrame-ReturnAddr | + // ... accessor frame data & args ... |- Descriptor.Size + // ActualArgc | + // CalleeToken |- JitFrameLayout::Size() + // Descriptor | + // FP -----> ReturnAddr | + masm.bind(&handle_IonAccessorIC); + { + // scratch2 := StackPointer + Descriptor.size + JitFrameLayout::Size() + masm.ma_add(StackPointer, scratch1, scratch2); + masm.addPtr(Imm32(JitFrameLayout::Size()), scratch2); + + // scratch3 := AccFrame-Descriptor.Size + masm.loadPtr(Address(scratch2, IonAccessorICFrameLayout::offsetOfDescriptor()), scratch3); +#ifdef DEBUG + // Assert previous frame is an IonJS frame. + masm.movePtr(scratch3, scratch1); + masm.and32(Imm32((1 << FRAMETYPE_BITS) - 1), scratch1); + { + Label checkOk; + masm.branch32(Assembler::Equal, scratch1, Imm32(JitFrame_IonJS), &checkOk); + masm.assumeUnreachable("IonAccessorIC frame must be preceded by IonJS frame"); + masm.bind(&checkOk); + } +#endif + masm.rshiftPtr(Imm32(FRAMESIZE_SHIFT), scratch3); + + // lastProfilingCallSite := AccFrame-ReturnAddr + masm.loadPtr(Address(scratch2, IonAccessorICFrameLayout::offsetOfReturnAddress()), scratch1); + masm.storePtr(scratch1, lastProfilingCallSite); + + // lastProfilingFrame := AccessorFrame + AccFrame-Descriptor.Size + + // IonAccessorICFrameLayout::Size() + masm.ma_add(scratch2, scratch3, scratch1); + masm.addPtr(Imm32(IonAccessorICFrameLayout::Size()), scratch1); + masm.storePtr(scratch1, lastProfilingFrame); + masm.ret(); + } + + // + // JitFrame_Entry + // + // If at an entry frame, store null into both fields. + // + masm.bind(&handle_Entry); + { + masm.movePtr(ImmPtr(nullptr), scratch1); + masm.storePtr(scratch1, lastProfilingCallSite); + masm.storePtr(scratch1, lastProfilingFrame); + masm.ret(); + } + + Linker linker(masm); + AutoFlushICache afc("ProfilerExitFrameTailStub"); + JitCode* code = linker.newCode<NoGC>(cx, OTHER_CODE); + +#ifdef JS_ION_PERF + writePerfSpewerJitCodeProfile(code, "ProfilerExitFrameStub"); +#endif + + return code; +} |