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_arm.h" 18 19 #include "mirror/art_method-inl.h" 20 #include "mirror/object-inl.h" 21 #include "quick/quick_method_frame_info.h" 22 #include "stack.h" 23 #include "thread.h" 24 25 namespace art { 26 namespace arm { 27 28 static constexpr uint32_t gZero = 0; 29 30 void ArmContext::Reset() { 31 for (size_t i = 0; i < kNumberOfCoreRegisters; i++) { 32 gprs_[i] = nullptr; 33 } 34 for (size_t i = 0; i < kNumberOfSRegisters; i++) { 35 fprs_[i] = nullptr; 36 } 37 gprs_[SP] = &sp_; 38 gprs_[PC] = &pc_; 39 // Initialize registers with easy to spot debug values. 40 sp_ = ArmContext::kBadGprBase + SP; 41 pc_ = ArmContext::kBadGprBase + PC; 42 } 43 44 void ArmContext::FillCalleeSaves(const StackVisitor& fr) { 45 mirror::ArtMethod* method = fr.GetMethod(); 46 const QuickMethodFrameInfo frame_info = method->GetQuickFrameInfo(); 47 size_t spill_count = POPCOUNT(frame_info.CoreSpillMask()); 48 size_t fp_spill_count = POPCOUNT(frame_info.FpSpillMask()); 49 if (spill_count > 0) { 50 // Lowest number spill is farthest away, walk registers and fill into context 51 int j = 1; 52 for (size_t i = 0; i < kNumberOfCoreRegisters; i++) { 53 if (((frame_info.CoreSpillMask() >> i) & 1) != 0) { 54 gprs_[i] = fr.CalleeSaveAddress(spill_count - j, frame_info.FrameSizeInBytes()); 55 j++; 56 } 57 } 58 } 59 if (fp_spill_count > 0) { 60 // Lowest number spill is farthest away, walk registers and fill into context 61 int j = 1; 62 for (size_t i = 0; i < kNumberOfSRegisters; i++) { 63 if (((frame_info.FpSpillMask() >> i) & 1) != 0) { 64 fprs_[i] = fr.CalleeSaveAddress(spill_count + fp_spill_count - j, 65 frame_info.FrameSizeInBytes()); 66 j++; 67 } 68 } 69 } 70 } 71 72 bool ArmContext::SetGPR(uint32_t reg, uintptr_t value) { 73 DCHECK_LT(reg, static_cast<uint32_t>(kNumberOfCoreRegisters)); 74 DCHECK_NE(gprs_[reg], &gZero); // Can't overwrite this static value since they are never reset. 75 if (gprs_[reg] != nullptr) { 76 *gprs_[reg] = value; 77 return true; 78 } else { 79 return false; 80 } 81 } 82 83 bool ArmContext::SetFPR(uint32_t reg, uintptr_t value) { 84 DCHECK_LT(reg, static_cast<uint32_t>(kNumberOfSRegisters)); 85 DCHECK_NE(fprs_[reg], &gZero); // Can't overwrite this static value since they are never reset. 86 if (fprs_[reg] != nullptr) { 87 *fprs_[reg] = value; 88 return true; 89 } else { 90 return false; 91 } 92 } 93 94 void ArmContext::SmashCallerSaves() { 95 // This needs to be 0 because we want a null/zero return value. 96 gprs_[R0] = const_cast<uint32_t*>(&gZero); 97 gprs_[R1] = const_cast<uint32_t*>(&gZero); 98 gprs_[R2] = nullptr; 99 gprs_[R3] = nullptr; 100 } 101 102 extern "C" void art_quick_do_long_jump(uint32_t*, uint32_t*); 103 104 void ArmContext::DoLongJump() { 105 uintptr_t gprs[kNumberOfCoreRegisters]; 106 uint32_t fprs[kNumberOfSRegisters]; 107 for (size_t i = 0; i < kNumberOfCoreRegisters; ++i) { 108 gprs[i] = gprs_[i] != nullptr ? *gprs_[i] : ArmContext::kBadGprBase + i; 109 } 110 for (size_t i = 0; i < kNumberOfSRegisters; ++i) { 111 fprs[i] = fprs_[i] != nullptr ? *fprs_[i] : ArmContext::kBadFprBase + i; 112 } 113 DCHECK_EQ(reinterpret_cast<uintptr_t>(Thread::Current()), gprs[TR]); 114 art_quick_do_long_jump(gprs, fprs); 115 } 116 117 } // namespace arm 118 } // namespace art 119
