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SharedICHelpers-arm64-inl.h (2626B)

      1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
      2 * vim: set ts=8 sts=2 et sw=2 tw=80:
      3 * This Source Code Form is subject to the terms of the Mozilla Public
      4 * License, v. 2.0. If a copy of the MPL was not distributed with this
      5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
      6 
      7 #ifndef jit_arm64_SharedICHelpers_arm64_inl_h
      8 #define jit_arm64_SharedICHelpers_arm64_inl_h
      9 
     10 #include "jit/BaselineFrame.h"
     11 #include "jit/SharedICHelpers.h"
     12 
     13 #include "jit/MacroAssembler-inl.h"
     14 
     15 namespace js {
     16 namespace jit {
     17 
     18 inline void EmitBaselineTailCallVM(TrampolinePtr target, MacroAssembler& masm,
     19                                   uint32_t argSize) {
     20 #ifdef DEBUG
     21  // We assume that R0 has been pushed, and R2 is unused.
     22  static_assert(R2 == ValueOperand(r0));
     23 
     24  // Store frame size without VMFunction arguments for debug assertions.
     25  masm.Sub(x0, FramePointer64, masm.GetStackPointer64());
     26  masm.Sub(w0, w0, Operand(argSize));
     27  Address frameSizeAddr(FramePointer,
     28                        BaselineFrame::reverseOffsetOfDebugFrameSize());
     29  masm.store32(w0.asUnsized(), frameSizeAddr);
     30 #endif
     31 
     32  // Push frame descriptor (minus the return address) and perform the tail call.
     33  static_assert(ICTailCallReg == lr);
     34  masm.push(FrameDescriptor(FrameType::BaselineJS));
     35 
     36  // The return address will be pushed by the VM wrapper, for compatibility
     37  // with direct calls. Refer to the top of generateVMWrapper().
     38  // ICTailCallReg (lr) already contains the return address (as we keep
     39  // it there through the stub calls).
     40 
     41  masm.jump(target);
     42 }
     43 
     44 inline void EmitBaselineCallVM(TrampolinePtr target, MacroAssembler& masm) {
     45  masm.push(FrameDescriptor(FrameType::BaselineStub));
     46  masm.call(target);
     47 }
     48 
     49 inline void EmitBaselineEnterStubFrame(MacroAssembler& masm, Register scratch) {
     50  MOZ_ASSERT(scratch != ICTailCallReg);
     51 
     52 #ifdef DEBUG
     53  // Compute frame size.
     54  masm.Sub(ARMRegister(scratch, 64), FramePointer64, masm.GetStackPointer64());
     55 
     56  Address frameSizeAddr(FramePointer,
     57                        BaselineFrame::reverseOffsetOfDebugFrameSize());
     58  masm.store32(scratch, frameSizeAddr);
     59 #endif
     60 
     61  // Push frame descriptor and return address.
     62  // Save old frame pointer, stack pointer, and stub reg.
     63  masm.Push(FrameDescriptor(FrameType::BaselineJS));
     64  masm.Push(ICTailCallReg);
     65  masm.Push(FramePointer);
     66 
     67  // Update the frame register.
     68  masm.Mov(FramePointer64, masm.GetStackPointer64());
     69 
     70  masm.Push(ICStubReg);
     71 
     72  // Stack should remain 16-byte aligned.
     73  masm.checkStackAlignment();
     74 }
     75 
     76 }  // namespace jit
     77 }  // namespace js
     78 
     79 #endif  // jit_arm64_SharedICHelpers_arm64_inl_h