Add m-esr52 at 52.6.0

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 */