1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
|
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* 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/BaselineIC.h"
#include "jit/JitFrames.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;
struct BaselineStubFrame {
uintptr_t savedFrame;
uintptr_t savedStub;
uintptr_t returnAddress;
uintptr_t descriptor;
};
// Size of values pushed by EmitBaselineEnterStubFrame.
static const uint32_t STUB_FRAME_SIZE = sizeof(BaselineStubFrame);
static const uint32_t STUB_FRAME_SAVED_STUB_OFFSET =
offsetof(BaselineStubFrame, savedStub);
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(MacroAssembler& masm, CodeOffset* callOffset) {
// The stub pointer must already be in ICStubReg.
// Load stubcode pointer from the ICStub.
// 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());
*callOffset = CodeOffset(masm.currentOffset());
}
inline void EmitReturnFromIC(MacroAssembler& masm) { masm.branch(ra); }
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);
}
template <typename AddrType>
inline void EmitPreBarrier(MacroAssembler& masm, const AddrType& addr,
MIRType type) {
// On MIPS, $ra is clobbered by guardedCallPreBarrier. Save it first.
masm.push(ra);
masm.guardedCallPreBarrier(addr, type);
masm.pop(ra);
}
inline void EmitStubGuardFailure(MacroAssembler& masm) {
// Load next stub into ICStubReg
masm.loadPtr(Address(ICStubReg, ICCacheIRStub::offsetOfNext()), ICStubReg);
// Return address is already loaded, just jump to the next stubcode.
MOZ_ASSERT(ICTailCallReg == ra);
masm.jump(Address(ICStubReg, ICStub::offsetOfStubCode()));
}
} // namespace jit
} // namespace js
#endif /* jit_mips_shared_SharedICHelpers_mips_shared_h */
|