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Diffstat (limited to 'js/src/jit/arm/SharedICHelpers-arm.h')
| -rw-r--r-- | js/src/jit/arm/SharedICHelpers-arm.h | 384 |
1 files changed, 384 insertions, 0 deletions
diff --git a/js/src/jit/arm/SharedICHelpers-arm.h b/js/src/jit/arm/SharedICHelpers-arm.h new file mode 100644 index 000000000..17534adef --- /dev/null +++ b/js/src/jit/arm/SharedICHelpers-arm.h @@ -0,0 +1,384 @@ +/* -*- 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/. */ + +#ifndef jit_arm_SharedICHelpers_arm_h +#define jit_arm_SharedICHelpers_arm_h + +#include "jit/BaselineFrame.h" +#include "jit/BaselineIC.h" +#include "jit/MacroAssembler.h" +#include "jit/SharedICRegisters.h" + +namespace js { +namespace jit { + +// Distance from sp to the top Value inside an IC stub (no return address on the stack on ARM). +static const size_t ICStackValueOffset = 0; + +inline void +EmitRestoreTailCallReg(MacroAssembler& masm) +{ + // No-op on ARM because link register is always holding the return address. +} + +inline void +EmitRepushTailCallReg(MacroAssembler& masm) +{ + // No-op on ARM because link register is always holding the return address. +} + +inline void +EmitCallIC(CodeOffset* patchOffset, MacroAssembler& masm) +{ + // Move ICEntry offset into ICStubReg + CodeOffset offset = masm.movWithPatch(ImmWord(-1), ICStubReg); + *patchOffset = offset; + + // Load stub pointer into ICStubReg + masm.loadPtr(Address(ICStubReg, ICEntry::offsetOfFirstStub()), ICStubReg); + + // Load stubcode pointer from BaselineStubEntry. + // R2 won't be active when we call ICs, so we can use r0. + MOZ_ASSERT(R2 == ValueOperand(r1, r0)); + masm.loadPtr(Address(ICStubReg, ICStub::offsetOfStubCode()), r0); + + // Call the stubcode via a direct branch-and-link. + masm.ma_blx(r0); +} + +inline void +EmitEnterTypeMonitorIC(MacroAssembler& masm, + size_t monitorStubOffset = ICMonitoredStub::offsetOfFirstMonitorStub()) +{ + // This is expected to be called from within an IC, when ICStubReg is + // properly initialized to point to the stub. + masm.loadPtr(Address(ICStubReg, (uint32_t) monitorStubOffset), ICStubReg); + + // Load stubcode pointer from BaselineStubEntry. + // R2 won't be active when we call ICs, so we can use r0. + MOZ_ASSERT(R2 == ValueOperand(r1, r0)); + masm.loadPtr(Address(ICStubReg, ICStub::offsetOfStubCode()), r0); + + // Jump to the stubcode. + masm.branch(r0); +} + +inline void +EmitReturnFromIC(MacroAssembler& masm) +{ + masm.ma_mov(lr, pc); +} + +inline void +EmitChangeICReturnAddress(MacroAssembler& masm, Register reg) +{ + masm.ma_mov(reg, lr); +} + +inline void +EmitBaselineTailCallVM(JitCode* target, MacroAssembler& masm, uint32_t argSize) +{ + // We assume during this that R0 and R1 have been pushed, and that R2 is + // unused. + MOZ_ASSERT(R2 == ValueOperand(r1, r0)); + + // Compute frame size. + masm.movePtr(BaselineFrameReg, r0); + masm.as_add(r0, r0, Imm8(BaselineFrame::FramePointerOffset)); + masm.ma_sub(BaselineStackReg, r0); + + // Store frame size without VMFunction arguments for GC marking. + { + ScratchRegisterScope scratch(masm); + masm.ma_sub(r0, Imm32(argSize), r1, scratch); + } + masm.store32(r1, Address(BaselineFrameReg, BaselineFrame::reverseOffsetOfFrameSize())); + + // Push frame descriptor and perform the tail call. + // ICTailCallReg (lr) already contains the return address (as we keep + // it there through the stub calls), but the VMWrapper code being called + // expects the return address to also be pushed on the stack. + MOZ_ASSERT(ICTailCallReg == lr); + masm.makeFrameDescriptor(r0, JitFrame_BaselineJS, ExitFrameLayout::Size()); + masm.push(r0); + masm.push(lr); + masm.branch(target); +} + +inline void +EmitIonTailCallVM(JitCode* target, MacroAssembler& masm, uint32_t stackSize) +{ + // We assume during this that R0 and R1 have been pushed, and that R2 is + // unused. + MOZ_ASSERT(R2 == ValueOperand(r1, r0)); + + masm.loadPtr(Address(sp, stackSize), r0); + masm.rshiftPtr(Imm32(FRAMESIZE_SHIFT), r0); + masm.add32(Imm32(stackSize + JitStubFrameLayout::Size() - sizeof(intptr_t)), r0); + + // Push frame descriptor and perform the tail call. + // ICTailCallReg (lr) already contains the return address (as we keep + // it there through the stub calls), but the VMWrapper code being called + // expects the return address to also be pushed on the stack. + MOZ_ASSERT(ICTailCallReg == lr); + masm.makeFrameDescriptor(r0, JitFrame_IonJS, ExitFrameLayout::Size()); + masm.push(r0); + masm.push(lr); + masm.branch(target); +} + +inline void +EmitBaselineCreateStubFrameDescriptor(MacroAssembler& masm, Register reg, uint32_t headerSize) +{ + // Compute stub frame size. We have to add two pointers: the stub reg and + // previous frame pointer pushed by EmitEnterStubFrame. + masm.mov(BaselineFrameReg, reg); + masm.as_add(reg, reg, Imm8(sizeof(void*) * 2)); + masm.ma_sub(BaselineStackReg, reg); + + masm.makeFrameDescriptor(reg, JitFrame_BaselineStub, headerSize); +} + +inline void +EmitBaselineCallVM(JitCode* target, MacroAssembler& masm) +{ + EmitBaselineCreateStubFrameDescriptor(masm, r0, ExitFrameLayout::Size()); + masm.push(r0); + masm.call(target); +} + +inline void +EmitIonCallVM(JitCode* target, size_t stackSlots, MacroAssembler& masm) +{ + uint32_t descriptor = MakeFrameDescriptor(masm.framePushed(), JitFrame_IonStub, + ExitFrameLayout::Size()); + masm.Push(Imm32(descriptor)); + masm.callJit(target); + + // Remove rest of the frame left on the stack. We remove the return address + // which is implicitly popped when returning. + size_t framePop = sizeof(ExitFrameLayout) - sizeof(void*); + + // Pop arguments from framePushed. + masm.implicitPop(stackSlots * sizeof(void*) + framePop); +} + +// Size of vales pushed by EmitEnterStubFrame. +static const uint32_t STUB_FRAME_SIZE = 4 * sizeof(void*); +static const uint32_t STUB_FRAME_SAVED_STUB_OFFSET = sizeof(void*); + +inline void +EmitBaselineEnterStubFrame(MacroAssembler& masm, Register scratch) +{ + MOZ_ASSERT(scratch != ICTailCallReg); + + // Compute frame size. + masm.mov(BaselineFrameReg, scratch); + masm.as_add(scratch, scratch, Imm8(BaselineFrame::FramePointerOffset)); + masm.ma_sub(BaselineStackReg, scratch); + + masm.store32(scratch, Address(BaselineFrameReg, BaselineFrame::reverseOffsetOfFrameSize())); + + // Note: when making changes here, don't forget to update STUB_FRAME_SIZE if + // needed. + + // Push frame descriptor and return address. + masm.makeFrameDescriptor(scratch, JitFrame_BaselineJS, BaselineStubFrameLayout::Size()); + masm.Push(scratch); + masm.Push(ICTailCallReg); + + // Save old frame pointer, stack pointer and stub reg. + masm.Push(ICStubReg); + masm.Push(BaselineFrameReg); + masm.mov(BaselineStackReg, BaselineFrameReg); + + // We pushed 4 words, so the stack is still aligned to 8 bytes. + masm.checkStackAlignment(); +} + +inline void +EmitIonEnterStubFrame(MacroAssembler& masm, Register scratch) +{ + MOZ_ASSERT(ICTailCallReg == lr); + + // In arm the link register contains the return address, + // but in jit frames we expect it to be on the stack. As a result + // push the link register (which is actually part of the previous frame. + // Therefore using push instead of Push). + masm.push(ICTailCallReg); + + masm.Push(ICStubReg); +} + +inline void +EmitBaselineLeaveStubFrame(MacroAssembler& masm, bool calledIntoIon = false) +{ + ScratchRegisterScope scratch(masm); + + // Ion frames do not save and restore the frame pointer. If we called into + // Ion, we have to restore the stack pointer from the frame descriptor. If + // we performed a VM call, the descriptor has been popped already so in that + // case we use the frame pointer. + if (calledIntoIon) { + masm.Pop(scratch); + masm.rshiftPtr(Imm32(FRAMESIZE_SHIFT), scratch); + masm.add32(scratch, BaselineStackReg); + } else { + masm.mov(BaselineFrameReg, BaselineStackReg); + } + + masm.Pop(BaselineFrameReg); + masm.Pop(ICStubReg); + + // Load the return address. + masm.Pop(ICTailCallReg); + + // Discard the frame descriptor. + masm.Pop(scratch); +} + +inline void +EmitIonLeaveStubFrame(MacroAssembler& masm) +{ + masm.Pop(ICStubReg); + masm.pop(ICTailCallReg); // See EmitIonEnterStubFrame for explanation on pop/Pop. +} + +inline void +EmitStowICValues(MacroAssembler& masm, int values) +{ + MOZ_ASSERT(values >= 0 && values <= 2); + switch(values) { + case 1: + // Stow R0. + masm.Push(R0); + break; + case 2: + // Stow R0 and R1. + masm.Push(R0); + masm.Push(R1); + break; + } +} + +inline void +EmitUnstowICValues(MacroAssembler& masm, int values, bool discard = false) +{ + MOZ_ASSERT(values >= 0 && values <= 2); + switch(values) { + case 1: + // Unstow R0. + if (discard) + masm.addPtr(Imm32(sizeof(Value)), BaselineStackReg); + else + masm.popValue(R0); + break; + case 2: + // Unstow R0 and R1. + if (discard) { + masm.addPtr(Imm32(sizeof(Value) * 2), BaselineStackReg); + } else { + masm.popValue(R1); + masm.popValue(R0); + } + break; + } + masm.adjustFrame(-values * sizeof(Value)); +} + +inline void +EmitCallTypeUpdateIC(MacroAssembler& masm, JitCode* code, uint32_t objectOffset) +{ + MOZ_ASSERT(R2 == ValueOperand(r1, r0)); + + // R0 contains the value that needs to be typechecked. The object we're + // updating is a boxed Value on the stack, at offset objectOffset from esp, + // excluding the return address. + + // Save the current ICStubReg to stack, as well as the TailCallReg, + // since on ARM, the LR is live. + masm.push(ICStubReg); + masm.push(ICTailCallReg); + + // This is expected to be called from within an IC, when ICStubReg is + // properly initialized to point to the stub. + masm.loadPtr(Address(ICStubReg, ICUpdatedStub::offsetOfFirstUpdateStub()), + ICStubReg); + + // TODO: Change r0 uses below to use masm's configurable scratch register instead. + + // Load stubcode pointer from ICStubReg into ICTailCallReg. + masm.loadPtr(Address(ICStubReg, ICStub::offsetOfStubCode()), r0); + + // Call the stubcode. + masm.ma_blx(r0); + + // Restore the old stub reg and tailcall reg. + masm.pop(ICTailCallReg); + masm.pop(ICStubReg); + + // The update IC will store 0 or 1 in R1.scratchReg() reflecting if the + // value in R0 type-checked properly or not. + Label success; + masm.cmp32(R1.scratchReg(), Imm32(1)); + masm.j(Assembler::Equal, &success); + + // If the IC failed, then call the update fallback function. + EmitBaselineEnterStubFrame(masm, R1.scratchReg()); + + masm.loadValue(Address(BaselineStackReg, STUB_FRAME_SIZE + objectOffset), R1); + + masm.Push(R0); + masm.Push(R1); + masm.Push(ICStubReg); + + // Load previous frame pointer, push BaselineFrame*. + masm.loadPtr(Address(BaselineFrameReg, 0), R0.scratchReg()); + masm.pushBaselineFramePtr(R0.scratchReg(), R0.scratchReg()); + + EmitBaselineCallVM(code, masm); + EmitBaselineLeaveStubFrame(masm); + + // Success at end. + masm.bind(&success); +} + +template <typename AddrType> +inline void +EmitPreBarrier(MacroAssembler& masm, const AddrType& addr, MIRType type) +{ + // On ARM, lr is clobbered by patchableCallPreBarrier. Save it first. + masm.push(lr); + masm.patchableCallPreBarrier(addr, type); + masm.pop(lr); +} + +inline void +EmitStubGuardFailure(MacroAssembler& masm) +{ + MOZ_ASSERT(R2 == ValueOperand(r1, r0)); + + // NOTE: This routine assumes that the stub guard code left the stack in the + // same state it was in when it was entered. + + // BaselineStubEntry points to the current stub. + + // Load next stub into ICStubReg. + masm.loadPtr(Address(ICStubReg, ICStub::offsetOfNext()), ICStubReg); + + // Load stubcode pointer from BaselineStubEntry into scratch register. + masm.loadPtr(Address(ICStubReg, ICStub::offsetOfStubCode()), r0); + + // Return address is already loaded, just jump to the next stubcode. + MOZ_ASSERT(ICTailCallReg == lr); + masm.branch(r0); +} + + +} // namespace jit +} // namespace js + +#endif /* jit_arm_SharedICHelpers_arm_h */ |