1 //===-- xray_mips64.cc ------------------------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file is a part of XRay, a dynamic runtime instrumentation system.
12 // Implementation of MIPS64-specific routines.
14 //===----------------------------------------------------------------------===//
15 #include "sanitizer_common/sanitizer_common.h"
16 #include "xray_defs.h"
17 #include "xray_interface_internal.h"
22 // The machine codes for some instructions used in runtime patching.
23 enum PatchOpcodes : uint32_t {
24 PO_DADDIU = 0x64000000, // daddiu rt, rs, imm
25 PO_SD = 0xFC000000, // sd rt, base(offset)
26 PO_LUI = 0x3C000000, // lui rt, imm
27 PO_ORI = 0x34000000, // ori rt, rs, imm
28 PO_DSLL = 0x00000038, // dsll rd, rt, sa
29 PO_JALR = 0x00000009, // jalr rs
30 PO_LD = 0xDC000000, // ld rt, base(offset)
31 PO_B60 = 0x1000000f, // b #60
35 enum RegNum : uint32_t {
42 inline static uint32_t encodeInstruction(uint32_t Opcode, uint32_t Rs,
44 uint32_t Imm) XRAY_NEVER_INSTRUMENT {
45 return (Opcode | Rs << 21 | Rt << 16 | Imm);
48 inline static uint32_t
49 encodeSpecialInstruction(uint32_t Opcode, uint32_t Rs, uint32_t Rt, uint32_t Rd,
50 uint32_t Imm) XRAY_NEVER_INSTRUMENT {
51 return (Rs << 21 | Rt << 16 | Rd << 11 | Imm << 6 | Opcode);
54 inline static bool patchSled(const bool Enable, const uint32_t FuncId,
55 const XRaySledEntry &Sled,
56 void (*TracingHook)()) XRAY_NEVER_INSTRUMENT {
57 // When |Enable| == true,
58 // We replace the following compile-time stub (sled):
65 // With the following runtime patch:
67 // xray_sled_n (64-bit):
68 // daddiu sp, sp, -16 ;create stack frame
70 // sd ra, 8(sp) ;save return address
71 // sd t9, 0(sp) ;save register t9
72 // lui t9, %highest(__xray_FunctionEntry/Exit)
73 // ori t9, t9, %higher(__xray_FunctionEntry/Exit)
75 // ori t9, t9, %hi(__xray_FunctionEntry/Exit)
77 // ori t9, t9, %lo(__xray_FunctionEntry/Exit)
78 // lui t0, %hi(function_id)
79 // jalr t9 ;call Tracing hook
80 // ori t0, t0, %lo(function_id) ;pass function id (delay slot)
81 // ld t9, 0(sp) ;restore register t9
82 // ld ra, 8(sp) ;restore return address
83 // daddiu sp, sp, 16 ;delete stack frame
85 // Replacement of the first 4-byte instruction should be the last and atomic
86 // operation, so that the user code which reaches the sled concurrently
87 // either jumps over the whole sled, or executes the whole sled when the
90 // When |Enable|==false, we set back the first instruction in the sled to be
94 uint32_t LoTracingHookAddr =
95 reinterpret_cast<int64_t>(TracingHook) & 0xffff;
96 uint32_t HiTracingHookAddr =
97 (reinterpret_cast<int64_t>(TracingHook) >> 16) & 0xffff;
98 uint32_t HigherTracingHookAddr =
99 (reinterpret_cast<int64_t>(TracingHook) >> 32) & 0xffff;
100 uint32_t HighestTracingHookAddr =
101 (reinterpret_cast<int64_t>(TracingHook) >> 48) & 0xffff;
102 uint32_t LoFunctionID = FuncId & 0xffff;
103 uint32_t HiFunctionID = (FuncId >> 16) & 0xffff;
104 *reinterpret_cast<uint32_t *>(Sled.Address + 8) = encodeInstruction(
105 PatchOpcodes::PO_SD, RegNum::RN_SP, RegNum::RN_RA, 0x8);
106 *reinterpret_cast<uint32_t *>(Sled.Address + 12) = encodeInstruction(
107 PatchOpcodes::PO_SD, RegNum::RN_SP, RegNum::RN_T9, 0x0);
108 *reinterpret_cast<uint32_t *>(Sled.Address + 16) = encodeInstruction(
109 PatchOpcodes::PO_LUI, 0x0, RegNum::RN_T9, HighestTracingHookAddr);
110 *reinterpret_cast<uint32_t *>(Sled.Address + 20) =
111 encodeInstruction(PatchOpcodes::PO_ORI, RegNum::RN_T9, RegNum::RN_T9,
112 HigherTracingHookAddr);
113 *reinterpret_cast<uint32_t *>(Sled.Address + 24) = encodeSpecialInstruction(
114 PatchOpcodes::PO_DSLL, 0x0, RegNum::RN_T9, RegNum::RN_T9, 0x10);
115 *reinterpret_cast<uint32_t *>(Sled.Address + 28) = encodeInstruction(
116 PatchOpcodes::PO_ORI, RegNum::RN_T9, RegNum::RN_T9, HiTracingHookAddr);
117 *reinterpret_cast<uint32_t *>(Sled.Address + 32) = encodeSpecialInstruction(
118 PatchOpcodes::PO_DSLL, 0x0, RegNum::RN_T9, RegNum::RN_T9, 0x10);
119 *reinterpret_cast<uint32_t *>(Sled.Address + 36) = encodeInstruction(
120 PatchOpcodes::PO_ORI, RegNum::RN_T9, RegNum::RN_T9, LoTracingHookAddr);
121 *reinterpret_cast<uint32_t *>(Sled.Address + 40) = encodeInstruction(
122 PatchOpcodes::PO_LUI, 0x0, RegNum::RN_T0, HiFunctionID);
123 *reinterpret_cast<uint32_t *>(Sled.Address + 44) = encodeSpecialInstruction(
124 PatchOpcodes::PO_JALR, RegNum::RN_T9, 0x0, RegNum::RN_RA, 0X0);
125 *reinterpret_cast<uint32_t *>(Sled.Address + 48) = encodeInstruction(
126 PatchOpcodes::PO_ORI, RegNum::RN_T0, RegNum::RN_T0, LoFunctionID);
127 *reinterpret_cast<uint32_t *>(Sled.Address + 52) = encodeInstruction(
128 PatchOpcodes::PO_LD, RegNum::RN_SP, RegNum::RN_T9, 0x0);
129 *reinterpret_cast<uint32_t *>(Sled.Address + 56) = encodeInstruction(
130 PatchOpcodes::PO_LD, RegNum::RN_SP, RegNum::RN_RA, 0x8);
131 *reinterpret_cast<uint32_t *>(Sled.Address + 60) = encodeInstruction(
132 PatchOpcodes::PO_DADDIU, RegNum::RN_SP, RegNum::RN_SP, 0x10);
133 uint32_t CreateStackSpace = encodeInstruction(
134 PatchOpcodes::PO_DADDIU, RegNum::RN_SP, RegNum::RN_SP, 0xfff0);
135 std::atomic_store_explicit(
136 reinterpret_cast<std::atomic<uint32_t> *>(Sled.Address),
137 CreateStackSpace, std::memory_order_release);
139 std::atomic_store_explicit(
140 reinterpret_cast<std::atomic<uint32_t> *>(Sled.Address),
141 uint32_t(PatchOpcodes::PO_B60), std::memory_order_release);
146 bool patchFunctionEntry(const bool Enable, const uint32_t FuncId,
147 const XRaySledEntry &Sled,
148 void (*Trampoline)()) XRAY_NEVER_INSTRUMENT {
149 return patchSled(Enable, FuncId, Sled, Trampoline);
152 bool patchFunctionExit(const bool Enable, const uint32_t FuncId,
153 const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT {
154 return patchSled(Enable, FuncId, Sled, __xray_FunctionExit);
157 bool patchFunctionTailExit(const bool Enable, const uint32_t FuncId,
158 const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT {
159 // FIXME: In the future we'd need to distinguish between non-tail exits and
160 // tail exits for better information preservation.
161 return patchSled(Enable, FuncId, Sled, __xray_FunctionExit);
164 bool patchCustomEvent(const bool Enable, const uint32_t FuncId,
165 const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT {
166 // FIXME: Implement in mips64?
170 bool patchTypedEvent(const bool Enable, const uint32_t FuncId,
171 const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT {
172 // FIXME: Implement in mips64?
175 } // namespace __xray
177 extern "C" void __xray_ArgLoggerEntry() XRAY_NEVER_INSTRUMENT {
178 // FIXME: this will have to be implemented in the trampoline assembly file