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diff --git a/js/src/jit/mips-shared/SharedICHelpers-mips-shared.h b/js/src/jit/mips-shared/SharedICHelpers-mips-shared.h
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index 0000000000..e665c92dd2
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+++ b/js/src/jit/mips-shared/SharedICHelpers-mips-shared.h
@@ -0,0 +1,382 @@
+/* -*- 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_mips_shared_SharedICHelpers_mips_shared_h
+#define jit_mips_shared_SharedICHelpers_mips_shared_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 MIPS).
+static const size_t ICStackValueOffset = 0;
+
+inline void
+EmitRestoreTailCallReg(MacroAssembler& masm)
+{
+    // No-op on MIPS because ra register is always holding the return address.
+}
+
+inline void
+EmitRepushTailCallReg(MacroAssembler& masm)
+{
+    // No-op on MIPS because ra 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 it as scratch.
+    masm.loadPtr(Address(ICStubReg, ICStub::offsetOfStubCode()), R2.scratchReg());
+
+    // Call the stubcode via a direct jump-and-link
+    masm.call(R2.scratchReg());
+}
+
+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 it.
+    masm.loadPtr(Address(ICStubReg, ICStub::offsetOfStubCode()), R2.scratchReg());
+
+    // Jump to the stubcode.
+    masm.branch(R2.scratchReg());
+}
+
+inline void
+EmitReturnFromIC(MacroAssembler& masm)
+{
+    masm.branch(ra);
+}
+
+inline void
+EmitChangeICReturnAddress(MacroAssembler& masm, Register reg)
+{
+    masm.movePtr(reg, ra);
+}
+
+inline void
+EmitBaselineTailCallVM(JitCode* target, MacroAssembler& masm, uint32_t argSize)
+{
+    Register scratch = R2.scratchReg();
+
+    // Compute frame size.
+    masm.movePtr(BaselineFrameReg, scratch);
+    masm.addPtr(Imm32(BaselineFrame::FramePointerOffset), scratch);
+    masm.subPtr(BaselineStackReg, scratch);
+
+    // Store frame size without VMFunction arguments for GC marking.
+    masm.subPtr(Imm32(argSize), scratch);
+    masm.store32(scratch, Address(BaselineFrameReg, BaselineFrame::reverseOffsetOfFrameSize()));
+    masm.addPtr(Imm32(argSize), scratch);
+
+    // Push frame descriptor and perform the tail call.
+    // ICTailCallReg (ra) 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 == ra);
+    masm.makeFrameDescriptor(scratch, JitFrame_BaselineJS, ExitFrameLayout::Size());
+    masm.subPtr(Imm32(sizeof(CommonFrameLayout)), StackPointer);
+    masm.storePtr(scratch, Address(StackPointer, CommonFrameLayout::offsetOfDescriptor()));
+    masm.storePtr(ra, Address(StackPointer, CommonFrameLayout::offsetOfReturnAddress()));
+
+    masm.branch(target);
+}
+
+inline void
+EmitIonTailCallVM(JitCode* target, MacroAssembler& masm, uint32_t stackSize)
+{
+    Register scratch = R2.scratchReg();
+
+    masm.loadPtr(Address(sp, stackSize), scratch);
+    masm.rshiftPtr(Imm32(FRAMESIZE_SHIFT), scratch);
+    masm.addPtr(Imm32(stackSize + JitStubFrameLayout::Size() - sizeof(intptr_t)), scratch);
+
+    // Push frame descriptor and perform the tail call.
+    MOZ_ASSERT(ICTailCallReg == ra);
+    masm.makeFrameDescriptor(scratch, JitFrame_IonJS, ExitFrameLayout::Size());
+    masm.push(scratch);
+    masm.push(ICTailCallReg);
+    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.movePtr(BaselineFrameReg, reg);
+    masm.addPtr(Imm32(sizeof(intptr_t) * 2), reg);
+    masm.subPtr(BaselineStackReg, reg);
+
+    masm.makeFrameDescriptor(reg, JitFrame_BaselineStub, headerSize);
+}
+
+inline void
+EmitBaselineCallVM(JitCode* target, MacroAssembler& masm)
+{
+    Register scratch = R2.scratchReg();
+    EmitBaselineCreateStubFrameDescriptor(masm, scratch, ExitFrameLayout::Size());
+    masm.push(scratch);
+    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);
+}
+
+struct BaselineStubFrame {
+    uintptr_t savedFrame;
+    uintptr_t savedStub;
+    uintptr_t returnAddress;
+    uintptr_t descriptor;
+};
+
+static const uint32_t STUB_FRAME_SIZE = sizeof(BaselineStubFrame);
+static const uint32_t STUB_FRAME_SAVED_STUB_OFFSET = offsetof(BaselineStubFrame, savedStub);
+
+inline void
+EmitBaselineEnterStubFrame(MacroAssembler& masm, Register scratch)
+{
+    MOZ_ASSERT(scratch != ICTailCallReg);
+
+    // Compute frame size.
+    masm.movePtr(BaselineFrameReg, scratch);
+    masm.addPtr(Imm32(BaselineFrame::FramePointerOffset), scratch);
+    masm.subPtr(BaselineStackReg, scratch);
+
+    masm.store32(scratch, Address(BaselineFrameReg, BaselineFrame::reverseOffsetOfFrameSize()));
+
+    // Note: when making changes here, don't forget to update
+    // BaselineStubFrame if needed.
+
+    // Push frame descriptor and return address.
+    masm.makeFrameDescriptor(scratch, JitFrame_BaselineJS, BaselineStubFrameLayout::Size());
+    masm.subPtr(Imm32(STUB_FRAME_SIZE), StackPointer);
+    masm.storePtr(scratch, Address(StackPointer, offsetof(BaselineStubFrame, descriptor)));
+    masm.storePtr(ICTailCallReg, Address(StackPointer,
+                                               offsetof(BaselineStubFrame, returnAddress)));
+
+    // Save old frame pointer, stack pointer and stub reg.
+    masm.storePtr(ICStubReg, Address(StackPointer,
+                                           offsetof(BaselineStubFrame, savedStub)));
+    masm.storePtr(BaselineFrameReg, Address(StackPointer,
+                                            offsetof(BaselineStubFrame, savedFrame)));
+    masm.movePtr(BaselineStackReg, BaselineFrameReg);
+
+    // Stack should remain aligned.
+    masm.assertStackAlignment(sizeof(Value), 0);
+}
+
+inline void
+EmitIonEnterStubFrame(MacroAssembler& masm, Register scratch)
+{
+    MOZ_ASSERT(ICTailCallReg == ra);
+
+    // In MIPS the ra 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)
+{
+    // 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(ScratchRegister);
+        masm.rshiftPtr(Imm32(FRAMESIZE_SHIFT), ScratchRegister);
+        masm.addPtr(ScratchRegister, BaselineStackReg);
+    } else {
+        masm.movePtr(BaselineFrameReg, BaselineStackReg);
+    }
+
+    masm.loadPtr(Address(StackPointer, offsetof(BaselineStubFrame, savedFrame)),
+                 BaselineFrameReg);
+    masm.loadPtr(Address(StackPointer, offsetof(BaselineStubFrame, savedStub)),
+                 ICStubReg);
+
+    // Load the return address.
+    masm.loadPtr(Address(StackPointer, offsetof(BaselineStubFrame, returnAddress)),
+                 ICTailCallReg);
+
+    // Discard the frame descriptor.
+    masm.loadPtr(Address(StackPointer, offsetof(BaselineStubFrame, descriptor)), ScratchRegister);
+    masm.addPtr(Imm32(STUB_FRAME_SIZE), StackPointer);
+}
+
+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);
+    }
+}
+
+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)
+{
+    // 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 $sp, excluding the return address.
+
+    // Save the current ICStubReg to stack, as well as the TailCallReg,
+    // since on mips, the $ra is live.
+    masm.subPtr(Imm32(2 * sizeof(intptr_t)), StackPointer);
+    masm.storePtr(ICStubReg, Address(StackPointer, sizeof(intptr_t)));
+    masm.storePtr(ICTailCallReg, Address(StackPointer, 0));
+
+    // 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);
+
+    // Load stubcode pointer from ICStubReg into ICTailCallReg.
+    masm.loadPtr(Address(ICStubReg, ICStub::offsetOfStubCode()), R2.scratchReg());
+
+    // Call the stubcode.
+    masm.call(R2.scratchReg());
+
+    // Restore the old stub reg and tailcall reg.
+    masm.loadPtr(Address(StackPointer, 0), ICTailCallReg);
+    masm.loadPtr(Address(StackPointer, sizeof(intptr_t)), ICStubReg);
+    masm.addPtr(Imm32(2 * sizeof(intptr_t)), StackPointer);
+
+    // 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.ma_b(R1.scratchReg(), Imm32(1), &success, Assembler::Equal, ShortJump);
+
+    // 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 MIPS, $ra is clobbered by patchableCallPreBarrier. Save it first.
+    masm.push(ra);
+    masm.patchableCallPreBarrier(addr, type);
+    masm.pop(ra);
+}
+
+inline void
+EmitStubGuardFailure(MacroAssembler& masm)
+{
+    // 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()), R2.scratchReg());
+
+    // Return address is already loaded, just jump to the next stubcode.
+    MOZ_ASSERT(ICTailCallReg == ra);
+    masm.branch(R2.scratchReg());
+}
+
+} // namespace jit
+} // namespace js
+
+#endif /* jit_mips_shared_SharedICHelpers_mips_shared_h */