context_mips.cc revision 6702243ea2332b566d8e8b871cc9db0906d835ad 
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 "object.h"
20
21namespace art {
22namespace mips {
23
24static const uint32_t gZero = 0;
25
26void MipsContext::Reset() {
27  for (size_t i = 0; i < kNumberOfCoreRegisters; i++) {
28    gprs_[i] = NULL;
29  }
30  for (size_t i = 0; i < kNumberOfFRegisters; i++) {
31    fprs_[i] = NULL;
32  }
33  gprs_[SP] = &sp_;
34  gprs_[RA] = &ra_;
35  // Initialize registers with easy to spot debug values.
36  sp_ = MipsContext::kBadGprBase + SP;
37  ra_ = MipsContext::kBadGprBase + RA;
38}
39
40void MipsContext::FillCalleeSaves(const StackVisitor& fr) {
41  AbstractMethod* method = fr.GetMethod();
42  uint32_t core_spills = method->GetCoreSpillMask();
43  uint32_t fp_core_spills = method->GetFpSpillMask();
44  size_t spill_count = __builtin_popcount(core_spills);
45  size_t fp_spill_count = __builtin_popcount(fp_core_spills);
46  size_t frame_size = method->GetFrameSizeInBytes();
47  if (spill_count > 0) {
48    // Lowest number spill is farthest away, walk registers and fill into context.
49    int j = 1;
50    for (size_t i = 0; i < kNumberOfCoreRegisters; i++) {
51      if (((core_spills >> i) & 1) != 0) {
52        gprs_[i] = fr.CalleeSaveAddress(spill_count - j, frame_size);
53        j++;
54      }
55    }
56  }
57  if (fp_spill_count > 0) {
58    // Lowest number spill is farthest away, walk registers and fill into context.
59    int j = 1;
60    for (size_t i = 0; i < kNumberOfFRegisters; i++) {
61      if (((fp_core_spills >> i) & 1) != 0) {
62        fprs_[i] = fr.CalleeSaveAddress(spill_count + fp_spill_count - j, frame_size);
63        j++;
64      }
65    }
66  }
67}
68
69void MipsContext::SetGPR(uint32_t reg, uintptr_t value) {
70  CHECK_LT(reg, kNumberOfCoreRegisters);
71  CHECK_NE(gprs_[reg], &gZero); // Can't overwrite this static value since they are never reset.
72  CHECK(gprs_[reg] != NULL);
73  *gprs_[reg] = value;
74}
75
76void MipsContext::SmashCallerSaves() {
77  // This needs to be 0 because we want a null/zero return value.
78  gprs_[V0] = const_cast<uint32_t*>(&gZero);
79  gprs_[V1] = const_cast<uint32_t*>(&gZero);
80  gprs_[A1] = NULL;
81  gprs_[A2] = NULL;
82  gprs_[A3] = NULL;
83}
84
85extern "C" void art_do_long_jump(uint32_t*, uint32_t*);
86
87void MipsContext::DoLongJump() {
88  uintptr_t gprs[kNumberOfCoreRegisters];
89  uint32_t fprs[kNumberOfFRegisters];
90  for (size_t i = 0; i < kNumberOfCoreRegisters; ++i) {
91    gprs[i] = gprs_[i] != NULL ? *gprs_[i] : MipsContext::kBadGprBase + i;
92  }
93  for (size_t i = 0; i < kNumberOfFRegisters; ++i) {
94    fprs[i] = fprs_[i] != NULL ? *fprs_[i] : MipsContext::kBadGprBase + i;
95  }
96  art_do_long_jump(gprs, fprs);
97}
98
99}  // namespace mips
100}  // namespace art
101