1 /* 2 * Copyright (C) 2011 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "context_mips.h" 18 19 #include "base/bit_utils.h" 20 #include "base/bit_utils_iterator.h" 21 #include "quick/quick_method_frame_info.h" 22 23 namespace art { 24 namespace mips { 25 26 static constexpr uint32_t gZero = 0; 27 28 void MipsContext::Reset() { 29 std::fill_n(gprs_, arraysize(gprs_), nullptr); 30 std::fill_n(fprs_, arraysize(fprs_), nullptr); 31 gprs_[SP] = &sp_; 32 gprs_[T9] = &t9_; 33 gprs_[A0] = &arg0_; 34 // Initialize registers with easy to spot debug values. 35 sp_ = MipsContext::kBadGprBase + SP; 36 t9_ = MipsContext::kBadGprBase + T9; 37 arg0_ = 0; 38 } 39 40 void MipsContext::FillCalleeSaves(uint8_t* frame, const QuickMethodFrameInfo& frame_info) { 41 int spill_pos = 0; 42 43 // Core registers come first, from the highest down to the lowest. 44 for (uint32_t core_reg : HighToLowBits(frame_info.CoreSpillMask())) { 45 // If the $ZERO register shows up in the list of registers to 46 // be saved this was only done to properly align the floating 47 // point register save locations to addresses which are 48 // multiples of 8. We only store the address of a register in 49 // gprs_ if the register is not the $ZERO register. The $ZERO 50 // register is read-only so there's never a reason to save it 51 // on the stack. 52 if (core_reg != 0u) { 53 gprs_[core_reg] = CalleeSaveAddress(frame, spill_pos, frame_info.FrameSizeInBytes()); 54 } 55 ++spill_pos; 56 } 57 DCHECK_EQ(spill_pos, POPCOUNT(frame_info.CoreSpillMask())); 58 59 // FP registers come second, from the highest down to the lowest. 60 for (uint32_t fp_reg : HighToLowBits(frame_info.FpSpillMask())) { 61 fprs_[fp_reg] = CalleeSaveAddress(frame, spill_pos, frame_info.FrameSizeInBytes()); 62 ++spill_pos; 63 } 64 DCHECK_EQ(spill_pos, POPCOUNT(frame_info.CoreSpillMask()) + POPCOUNT(frame_info.FpSpillMask())); 65 } 66 67 void MipsContext::SetGPR(uint32_t reg, uintptr_t value) { 68 CHECK_LT(reg, static_cast<uint32_t>(kNumberOfCoreRegisters)); 69 DCHECK(IsAccessibleGPR(reg)); 70 CHECK_NE(gprs_[reg], &gZero); // Can't overwrite this static value since they are never reset. 71 *gprs_[reg] = value; 72 } 73 74 void MipsContext::SetFPR(uint32_t reg, uintptr_t value) { 75 CHECK_LT(reg, static_cast<uint32_t>(kNumberOfFRegisters)); 76 DCHECK(IsAccessibleFPR(reg)); 77 CHECK_NE(fprs_[reg], &gZero); // Can't overwrite this static value since they are never reset. 78 *fprs_[reg] = value; 79 } 80 81 void MipsContext::SmashCallerSaves() { 82 // This needs to be 0 because we want a null/zero return value. 83 gprs_[V0] = const_cast<uint32_t*>(&gZero); 84 gprs_[V1] = const_cast<uint32_t*>(&gZero); 85 gprs_[A1] = nullptr; 86 gprs_[A2] = nullptr; 87 gprs_[A3] = nullptr; 88 gprs_[T0] = nullptr; 89 gprs_[T1] = nullptr; 90 91 fprs_[F8] = nullptr; 92 fprs_[F9] = nullptr; 93 fprs_[F10] = nullptr; 94 fprs_[F11] = nullptr; 95 fprs_[F12] = nullptr; 96 fprs_[F13] = nullptr; 97 fprs_[F14] = nullptr; 98 fprs_[F15] = nullptr; 99 fprs_[F16] = nullptr; 100 fprs_[F17] = nullptr; 101 fprs_[F18] = nullptr; 102 fprs_[F19] = nullptr; 103 } 104 105 extern "C" NO_RETURN void art_quick_do_long_jump(uint32_t*, uint32_t*); 106 107 void MipsContext::DoLongJump() { 108 uintptr_t gprs[kNumberOfCoreRegisters]; 109 // Align fprs[] so that art_quick_do_long_jump() can load FPU 110 // registers from it using the ldc1 instruction. 111 uint32_t fprs[kNumberOfFRegisters] __attribute__((aligned(8))); 112 for (size_t i = 0; i < kNumberOfCoreRegisters; ++i) { 113 gprs[i] = gprs_[i] != nullptr ? *gprs_[i] : MipsContext::kBadGprBase + i; 114 } 115 for (size_t i = 0; i < kNumberOfFRegisters; ++i) { 116 fprs[i] = fprs_[i] != nullptr ? *fprs_[i] : MipsContext::kBadFprBase + i; 117 } 118 art_quick_do_long_jump(gprs, fprs); 119 } 120 121 } // namespace mips 122 } // namespace art 123
