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Diffstat (limited to 'lib/xray/xray_mips.cc')
| -rw-r--r-- | lib/xray/xray_mips.cc | 170 |
1 files changed, 0 insertions, 170 deletions
diff --git a/lib/xray/xray_mips.cc b/lib/xray/xray_mips.cc deleted file mode 100644 index 80990ab8d639f..0000000000000 --- a/lib/xray/xray_mips.cc +++ /dev/null @@ -1,170 +0,0 @@ -//===-- xray_mips.cc --------------------------------------------*- C++ -*-===// -// -// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. -// See https://llvm.org/LICENSE.txt for license information. -// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception -// -//===----------------------------------------------------------------------===// -// -// This file is a part of XRay, a dynamic runtime instrumentation system. -// -// Implementation of MIPS-specific routines (32-bit). -// -//===----------------------------------------------------------------------===// -#include "sanitizer_common/sanitizer_common.h" -#include "xray_defs.h" -#include "xray_interface_internal.h" -#include <atomic> - -namespace __xray { - -// The machine codes for some instructions used in runtime patching. -enum PatchOpcodes : uint32_t { - PO_ADDIU = 0x24000000, // addiu rt, rs, imm - PO_SW = 0xAC000000, // sw rt, offset(sp) - PO_LUI = 0x3C000000, // lui rs, %hi(address) - PO_ORI = 0x34000000, // ori rt, rs, %lo(address) - PO_JALR = 0x0000F809, // jalr rs - PO_LW = 0x8C000000, // lw rt, offset(address) - PO_B44 = 0x1000000b, // b #44 - PO_NOP = 0x0, // nop -}; - -enum RegNum : uint32_t { - RN_T0 = 0x8, - RN_T9 = 0x19, - RN_RA = 0x1F, - RN_SP = 0x1D, -}; - -inline static uint32_t encodeInstruction(uint32_t Opcode, uint32_t Rs, - uint32_t Rt, - uint32_t Imm) XRAY_NEVER_INSTRUMENT { - return (Opcode | Rs << 21 | Rt << 16 | Imm); -} - -inline static uint32_t -encodeSpecialInstruction(uint32_t Opcode, uint32_t Rs, uint32_t Rt, uint32_t Rd, - uint32_t Imm) XRAY_NEVER_INSTRUMENT { - return (Rs << 21 | Rt << 16 | Rd << 11 | Imm << 6 | Opcode); -} - -inline static bool patchSled(const bool Enable, const uint32_t FuncId, - const XRaySledEntry &Sled, - void (*TracingHook)()) XRAY_NEVER_INSTRUMENT { - // When |Enable| == true, - // We replace the following compile-time stub (sled): - // - // xray_sled_n: - // B .tmpN - // 11 NOPs (44 bytes) - // .tmpN - // ADDIU T9, T9, 44 - // - // With the following runtime patch: - // - // xray_sled_n (32-bit): - // addiu sp, sp, -8 ;create stack frame - // nop - // sw ra, 4(sp) ;save return address - // sw t9, 0(sp) ;save register t9 - // lui t9, %hi(__xray_FunctionEntry/Exit) - // ori t9, t9, %lo(__xray_FunctionEntry/Exit) - // lui t0, %hi(function_id) - // jalr t9 ;call Tracing hook - // ori t0, t0, %lo(function_id) ;pass function id (delay slot) - // lw t9, 0(sp) ;restore register t9 - // lw ra, 4(sp) ;restore return address - // addiu sp, sp, 8 ;delete stack frame - // - // We add 44 bytes to t9 because we want to adjust the function pointer to - // the actual start of function i.e. the address just after the noop sled. - // We do this because gp displacement relocation is emitted at the start of - // of the function i.e after the nop sled and to correctly calculate the - // global offset table address, t9 must hold the address of the instruction - // containing the gp displacement relocation. - // FIXME: Is this correct for the static relocation model? - // - // Replacement of the first 4-byte instruction should be the last and atomic - // operation, so that the user code which reaches the sled concurrently - // either jumps over the whole sled, or executes the whole sled when the - // latter is ready. - // - // When |Enable|==false, we set back the first instruction in the sled to be - // B #44 - - if (Enable) { - uint32_t LoTracingHookAddr = - reinterpret_cast<int32_t>(TracingHook) & 0xffff; - uint32_t HiTracingHookAddr = - (reinterpret_cast<int32_t>(TracingHook) >> 16) & 0xffff; - uint32_t LoFunctionID = FuncId & 0xffff; - uint32_t HiFunctionID = (FuncId >> 16) & 0xffff; - *reinterpret_cast<uint32_t *>(Sled.Address + 8) = encodeInstruction( - PatchOpcodes::PO_SW, RegNum::RN_SP, RegNum::RN_RA, 0x4); - *reinterpret_cast<uint32_t *>(Sled.Address + 12) = encodeInstruction( - PatchOpcodes::PO_SW, RegNum::RN_SP, RegNum::RN_T9, 0x0); - *reinterpret_cast<uint32_t *>(Sled.Address + 16) = encodeInstruction( - PatchOpcodes::PO_LUI, 0x0, RegNum::RN_T9, HiTracingHookAddr); - *reinterpret_cast<uint32_t *>(Sled.Address + 20) = encodeInstruction( - PatchOpcodes::PO_ORI, RegNum::RN_T9, RegNum::RN_T9, LoTracingHookAddr); - *reinterpret_cast<uint32_t *>(Sled.Address + 24) = encodeInstruction( - PatchOpcodes::PO_LUI, 0x0, RegNum::RN_T0, HiFunctionID); - *reinterpret_cast<uint32_t *>(Sled.Address + 28) = encodeSpecialInstruction( - PatchOpcodes::PO_JALR, RegNum::RN_T9, 0x0, RegNum::RN_RA, 0X0); - *reinterpret_cast<uint32_t *>(Sled.Address + 32) = encodeInstruction( - PatchOpcodes::PO_ORI, RegNum::RN_T0, RegNum::RN_T0, LoFunctionID); - *reinterpret_cast<uint32_t *>(Sled.Address + 36) = encodeInstruction( - PatchOpcodes::PO_LW, RegNum::RN_SP, RegNum::RN_T9, 0x0); - *reinterpret_cast<uint32_t *>(Sled.Address + 40) = encodeInstruction( - PatchOpcodes::PO_LW, RegNum::RN_SP, RegNum::RN_RA, 0x4); - *reinterpret_cast<uint32_t *>(Sled.Address + 44) = encodeInstruction( - PatchOpcodes::PO_ADDIU, RegNum::RN_SP, RegNum::RN_SP, 0x8); - uint32_t CreateStackSpaceInstr = encodeInstruction( - PatchOpcodes::PO_ADDIU, RegNum::RN_SP, RegNum::RN_SP, 0xFFF8); - std::atomic_store_explicit( - reinterpret_cast<std::atomic<uint32_t> *>(Sled.Address), - uint32_t(CreateStackSpaceInstr), std::memory_order_release); - } else { - std::atomic_store_explicit( - reinterpret_cast<std::atomic<uint32_t> *>(Sled.Address), - uint32_t(PatchOpcodes::PO_B44), std::memory_order_release); - } - return true; -} - -bool patchFunctionEntry(const bool Enable, const uint32_t FuncId, - const XRaySledEntry &Sled, - void (*Trampoline)()) XRAY_NEVER_INSTRUMENT { - return patchSled(Enable, FuncId, Sled, Trampoline); -} - -bool patchFunctionExit(const bool Enable, const uint32_t FuncId, - const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT { - return patchSled(Enable, FuncId, Sled, __xray_FunctionExit); -} - -bool patchFunctionTailExit(const bool Enable, const uint32_t FuncId, - const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT { - // FIXME: In the future we'd need to distinguish between non-tail exits and - // tail exits for better information preservation. - return patchSled(Enable, FuncId, Sled, __xray_FunctionExit); -} - -bool patchCustomEvent(const bool Enable, const uint32_t FuncId, - const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT { - // FIXME: Implement in mips? - return false; -} - -bool patchTypedEvent(const bool Enable, const uint32_t FuncId, - const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT { - // FIXME: Implement in mips? - return false; -} - -} // namespace __xray - -extern "C" void __xray_ArgLoggerEntry() XRAY_NEVER_INSTRUMENT { - // FIXME: this will have to be implemented in the trampoline assembly file -} |