stack_walk_refmap_jni.cc revision 1c83cbc4a817acbd7f9abb5b29a2d418a958e6a1 
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 <stdio.h>
18#include <memory>
19
20#include "class_linker.h"
21#include "dex_file-inl.h"
22#include "gc_map.h"
23#include "mirror/art_method-inl.h"
24#include "mirror/class-inl.h"
25#include "mirror/object_array-inl.h"
26#include "mirror/object-inl.h"
27#include "scoped_thread_state_change.h"
28#include "thread.h"
29#include "jni.h"
30#include "verifier/method_verifier.h"
31
32namespace art {
33
34#define IS_IN_REF_BITMAP(ref_bitmap, reg) \
35    (((reg) < m->GetCodeItem()->registers_size_) && \
36     ((*((ref_bitmap) + (reg)/8) >> ((reg) % 8) ) & 0x01))
37
38#define CHECK_REGS_CONTAIN_REFS(...)     \
39  do {                                   \
40    int t[] = {__VA_ARGS__};             \
41    int t_size = sizeof(t) / sizeof(*t);      \
42    for (int i = 0; i < t_size; ++i)          \
43      CHECK(IS_IN_REF_BITMAP(ref_bitmap, t[i])) \
44          << "Error: Reg @ " << i << "-th argument is not in GC map"; \
45  } while (false)
46
47struct ReferenceMap2Visitor : public StackVisitor {
48  explicit ReferenceMap2Visitor(Thread* thread)
49      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
50      : StackVisitor(thread, NULL) {
51  }
52
53  bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
54    mirror::ArtMethod* m = GetMethod();
55    if (!m || m->IsNative() || m->IsRuntimeMethod() || IsShadowFrame()) {
56      return true;
57    }
58    LOG(INFO) << "At " << PrettyMethod(m, false);
59
60    NativePcOffsetToReferenceMap map(m->GetNativeGcMap());
61
62    if (m->IsCalleeSaveMethod()) {
63      LOG(WARNING) << "no PC for " << PrettyMethod(m);
64      return true;
65    }
66
67    const uint8_t* ref_bitmap = NULL;
68    std::string m_name(m->GetName());
69
70    // Given the method name and the number of times the method has been called,
71    // we know the Dex registers with live reference values. Assert that what we
72    // find is what is expected.
73    if (m_name.compare("f") == 0) {
74      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x03U)));
75      CHECK(ref_bitmap);
76      CHECK_REGS_CONTAIN_REFS(8);  // v8: this
77
78      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x06U)));
79      CHECK(ref_bitmap);
80      CHECK_REGS_CONTAIN_REFS(8, 1);  // v8: this, v1: x
81
82      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x08U)));
83      CHECK(ref_bitmap);
84      CHECK_REGS_CONTAIN_REFS(8, 3, 1);  // v8: this, v3: y, v1: x
85
86      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x0cU)));
87      CHECK(ref_bitmap);
88      CHECK_REGS_CONTAIN_REFS(8, 3, 1);  // v8: this, v3: y, v1: x
89
90      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x0eU)));
91      CHECK(ref_bitmap);
92      CHECK_REGS_CONTAIN_REFS(8, 3, 1);  // v8: this, v3: y, v1: x
93
94      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x10U)));
95      CHECK(ref_bitmap);
96      CHECK_REGS_CONTAIN_REFS(8, 3, 1);  // v8: this, v3: y, v1: x
97
98      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x13U)));
99      CHECK(ref_bitmap);
100      // v2 is added because of the instruction at DexPC 0024. Object merges with 0 is Object. See:
101      //   0024: move-object v3, v2
102      //   0025: goto 0013
103      // Detaled dex instructions for ReferenceMap.java are at the end of this function.
104      // CHECK_REGS_CONTAIN_REFS(8, 3, 2, 1);  // v8: this, v3: y, v2: y, v1: x
105      // We eliminate the non-live registers at a return, so only v3 is live:
106      CHECK_REGS_CONTAIN_REFS(3);  // v3: y
107
108      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x18U)));
109      CHECK(ref_bitmap);
110      CHECK_REGS_CONTAIN_REFS(8, 2, 1, 0);  // v8: this, v2: y, v1: x, v0: ex
111
112      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x1aU)));
113      CHECK(ref_bitmap);
114      CHECK_REGS_CONTAIN_REFS(8, 5, 2, 1, 0);  // v8: this, v5: x[1], v2: y, v1: x, v0: ex
115
116      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x1dU)));
117      CHECK(ref_bitmap);
118      CHECK_REGS_CONTAIN_REFS(8, 5, 2, 1, 0);  // v8: this, v5: x[1], v2: y, v1: x, v0: ex
119
120      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x1fU)));
121      CHECK(ref_bitmap);
122      // v5 is removed from the root set because there is a "merge" operation.
123      // See 0015: if-nez v2, 001f.
124      CHECK_REGS_CONTAIN_REFS(8, 2, 1, 0);  // v8: this, v2: y, v1: x, v0: ex
125
126      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x21U)));
127      CHECK(ref_bitmap);
128      CHECK_REGS_CONTAIN_REFS(8, 2, 1, 0);  // v8: this, v2: y, v1: x, v0: ex
129
130      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x27U)));
131      CHECK(ref_bitmap);
132      CHECK_REGS_CONTAIN_REFS(8, 4, 2, 1);  // v8: this, v4: ex, v2: y, v1: x
133
134      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x29U)));
135      CHECK(ref_bitmap);
136      CHECK_REGS_CONTAIN_REFS(8, 4, 2, 1);  // v8: this, v4: ex, v2: y, v1: x
137
138      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x2cU)));
139      CHECK(ref_bitmap);
140      CHECK_REGS_CONTAIN_REFS(8, 4, 2, 1);  // v8: this, v4: ex, v2: y, v1: x
141
142      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x2fU)));
143      CHECK(ref_bitmap);
144      CHECK_REGS_CONTAIN_REFS(8, 4, 3, 2, 1);  // v8: this, v4: ex, v3: y, v2: y, v1: x
145
146      ref_bitmap = map.FindBitMap(m->NativePcOffset(m->ToNativePc(0x32U)));
147      CHECK(ref_bitmap);
148      CHECK_REGS_CONTAIN_REFS(8, 3, 2, 1, 0);  // v8: this, v3: y, v2: y, v1: x, v0: ex
149    }
150
151    return true;
152  }
153};
154
155// Dex instructions for the function 'f' in ReferenceMap.java
156// Virtual methods   -
157//    #0              : (in LReferenceMap;)
158//      name          : 'f'
159//      type          : '()Ljava/lang/Object;'
160//      access        : 0x0000 ()
161//      code          -
162//      registers     : 9
163//      ins           : 1
164//      outs          : 2
165//      insns size    : 51 16-bit code units
166//      |[0001e8] ReferenceMap.f:()Ljava/lang/Object;
167//      |0000: const/4 v4, #int 2 // #2
168//      |0001: const/4 v7, #int 0 // #0
169//      |0002: const/4 v6, #int 1 // #1
170//
171// 0:[Unknown],1:[Unknown],2:[Unknown],3:[Unknown],4:[32-bit Constant: 2],5:[Unknown],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
172//      |0003: new-array v1, v4, [Ljava/lang/Object;  // type@0007
173//      |0005: const/4 v2, #int 0 // #0
174
175// 0:[Unknown],1:[Reference: java.lang.Object[]],2:[Zero],3:[Unknown],4:[32-bit Constant: 2],5:[Unknown],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
176//      |0006: new-instance v3, Ljava/lang/Object;  // type@0003
177
178// [Unknown],1:[Reference: java.lang.Object[]],2:[Zero],3:[Uninitialized Reference: java.lang.Object],4:[32-bit Constant: 2],5:[Unknown],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
179//      |0008: +invoke-object-init/range {}, Ljava/lang/Object;.<init>:()V // method@0005
180//      |000b: const/4 v4, #int 2 // #2
181
182// 0:[Unknown],1:[Reference: java.lang.Object[]],2:[Zero],3:[Reference: java.lang.Object],4:[32-bit Constant: 2],5:[Unknown],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
183//      |000c: aput-object v3, v1, v4
184
185// 0:[Unknown],1:[Reference: java.lang.Object[]],2:[Zero],3:[Reference: java.lang.Object],4:[32-bit Constant: 2],5:[Unknown],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
186//      |000e: aput-object v3, v1, v6
187
188// 0:[Unknown],1:[Reference: java.lang.Object[]],2:[Zero],3:[Reference: java.lang.Object],4:[32-bit Constant: 2],5:[Unknown],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
189//      |0010: +invoke-virtual-quick {v8, v7}, [000c] // vtable #000c
190
191// 0:[Conflict],1:[Conflict],2:[Conflict],3:[Reference: java.lang.Object],4:[Conflict],5:[Conflict],6:[Conflict],7:[Conflict],8:[Conflict],
192//      |0013: return-object v3
193//      |0014: move-exception v0
194
195// 0:[Reference: java.lang.Exception],1:[Reference: java.lang.Object[]],2:[Reference: java.lang.Object],3:[Conflict],4:[32-bit Constant: 2],5:[Unknown],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
196//      |0015: if-nez v2, 001f // +000a
197//      |0017: const/4 v4, #int 1 // #1
198
199// 0:[Reference: java.lang.Exception],1:[Reference: java.lang.Object[]],2:[Reference: java.lang.Object],3:[Conflict],4:[32-bit Constant: 1],5:[Unknown],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
200//      |0018: new-instance v5, Ljava/lang/Object;  // type@0003
201
202// 0:[Reference: java.lang.Exception],1:[Reference: java.lang.Object[]],2:[Reference: java.lang.Object],3:[Conflict],4:[32-bit Constant: 1],5:[Uninitialized Reference: java.lang.Object],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
203//      |001a: +invoke-object-init/range {}, Ljava/lang/Object;.<init>:()V // method@0005
204
205// 0:[Reference: java.lang.Exception],1:[Reference: java.lang.Object[]],2:[Reference: java.lang.Object],3:[Conflict],4:[32-bit Constant: 1],5:[Reference: java.lang.Object],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
206//      |001d: aput-object v5, v1, v4
207
208// 0:[Reference: java.lang.Exception],1:[Reference: java.lang.Object[]],2:[Reference: java.lang.Object],3:[Conflict],4:[32-bit Constant: 2],5:[Conflict],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
209//      |001f: aput-object v2, v1, v6
210
211// 0:[Reference: java.lang.Exception],1:[Reference: java.lang.Object[]],2:[Reference: java.lang.Object],3:[Conflict],4:[32-bit Constant: 2],5:[Conflict],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
212//      |0021: +invoke-virtual-quick {v8, v7}, [000c] // vtable #000c
213//      |0024: move-object v3, v2
214
215// 0:[Reference: java.lang.Exception],1:[Reference: java.lang.Object[]],2:[Reference: java.lang.Object],3:[Reference: java.lang.Object],4:[32-bit Constant: 2],5:[Conflict],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
216//      |0025: goto 0013 // -0012
217//      |0026: move-exception v4
218
219// 0:[Conflict],1:[Reference: java.lang.Object[]],2:[Reference: java.lang.Object],3:[Conflict],4:[Reference: java.lang.Throwable],5:[Conflict],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
220//      |0027: aput-object v2, v1, v6
221
222// 0:[Conflict],1:[Reference: java.lang.Object[]],2:[Reference: java.lang.Object],3:[Conflict],4:[Reference: java.lang.Throwable],5:[Conflict],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
223//      |0029: +invoke-virtual-quick {v8, v7}, [000c] // vtable #000c
224
225// 0:[Conflict],1:[Reference: java.lang.Object[]],2:[Reference: java.lang.Object],3:[Conflict],4:[Reference: java.lang.Throwable],5:[Conflict],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
226//      |002c: throw v4
227//      |002d: move-exception v4
228//      |002e: move-object v2, v3
229
230// 0:[Unknown],1:[Reference: java.lang.Object[]],2:[Reference: java.lang.Object],3:[Reference: java.lang.Object],4:[Reference: java.lang.Throwable],5:[Unknown],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
231//      |002f: goto 0027 // -0008
232//      |0030: move-exception v0
233//      |0031: move-object v2, v3
234
235// 0:[Reference: java.lang.Exception],1:[Reference: java.lang.Object[]],2:[Reference: java.lang.Object],3:[Reference: java.lang.Object],4:[32-bit Constant: 2],5:[Unknown],6:[32-bit Constant: 1],7:[Zero],8:[Reference: ReferenceMap],
236//      |0032: goto 0015 // -001d
237//      catches       : 3
238//        0x0006 - 0x000b
239//          Ljava/lang/Exception; -> 0x0014
240//          <any> -> 0x0026
241//        0x000c - 0x000e
242//          Ljava/lang/Exception; -> 0x0030
243//          <any> -> 0x002d
244//        0x0018 - 0x001f
245//          <any> -> 0x0026
246//      positions     :
247//        0x0003 line=8
248//        0x0005 line=9
249//        0x0006 line=11
250//        0x000b line=12
251//        0x000e line=18
252//        0x0010 line=19
253//        0x0013 line=21
254//        0x0014 line=13
255//        0x0015 line=14
256//        0x0017 line=15
257//        0x001f line=18
258//        0x0021 line=19
259//        0x0025 line=20
260//        0x0026 line=18
261//        0x0029 line=19
262//        0x002d line=18
263//        0x0030 line=13
264//      locals        :
265//        0x0006 - 0x000b reg=2 y Ljava/lang/Object;
266//        0x000b - 0x0013 reg=3 y Ljava/lang/Object;
267//        0x0014 - 0x0015 reg=2 y Ljava/lang/Object;
268//        0x0015 - 0x0026 reg=0 ex Ljava/lang/Exception;
269//        0x002d - 0x0032 reg=3 y Ljava/lang/Object;
270//        0x0005 - 0x0033 reg=1 x [Ljava/lang/Object;
271//        0x0032 - 0x0033 reg=2 y Ljava/lang/Object;
272//        0x0000 - 0x0033 reg=8 this LReferenceMap;
273
274extern "C" JNIEXPORT jint JNICALL Java_Main_refmap(JNIEnv*, jobject, jint count) {
275  // Visitor
276  ScopedObjectAccess soa(Thread::Current());
277  ReferenceMap2Visitor mapper(soa.Self());
278  mapper.WalkStack();
279
280  return count + 1;
281}
282
283}  // namespace art
284