1 //===- llvm/unittest/Bitcode/BitReaderTest.cpp - Tests for BitReader ------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "llvm/ADT/SmallString.h"
11 #include "llvm/ADT/STLExtras.h"
12 #include "llvm/AsmParser/Parser.h"
13 #include "llvm/Bitcode/BitstreamReader.h"
14 #include "llvm/Bitcode/BitstreamWriter.h"
15 #include "llvm/Bitcode/ReaderWriter.h"
16 #include "llvm/IR/Constants.h"
17 #include "llvm/IR/Instructions.h"
18 #include "llvm/IR/LLVMContext.h"
19 #include "llvm/IR/Module.h"
20 #include "llvm/IR/Verifier.h"
21 #include "llvm/Support/DataStream.h"
22 #include "llvm/Support/Debug.h"
23 #include "llvm/Support/MemoryBuffer.h"
24 #include "llvm/Support/SourceMgr.h"
25 #include "llvm/Support/StreamingMemoryObject.h"
26 #include "gtest/gtest.h"
27
28 using namespace llvm;
29
30 namespace {
31
parseAssembly(LLVMContext & Context,const char * Assembly)32 std::unique_ptr<Module> parseAssembly(LLVMContext &Context,
33 const char *Assembly) {
34 SMDiagnostic Error;
35 std::unique_ptr<Module> M = parseAssemblyString(Assembly, Error, Context);
36
37 std::string ErrMsg;
38 raw_string_ostream OS(ErrMsg);
39 Error.print("", OS);
40
41 // A failure here means that the test itself is buggy.
42 if (!M)
43 report_fatal_error(OS.str().c_str());
44
45 return M;
46 }
47
writeModuleToBuffer(std::unique_ptr<Module> Mod,SmallVectorImpl<char> & Buffer)48 static void writeModuleToBuffer(std::unique_ptr<Module> Mod,
49 SmallVectorImpl<char> &Buffer) {
50 raw_svector_ostream OS(Buffer);
51 WriteBitcodeToFile(Mod.get(), OS);
52 }
53
getLazyModuleFromAssembly(LLVMContext & Context,SmallString<1024> & Mem,const char * Assembly)54 static std::unique_ptr<Module> getLazyModuleFromAssembly(LLVMContext &Context,
55 SmallString<1024> &Mem,
56 const char *Assembly) {
57 writeModuleToBuffer(parseAssembly(Context, Assembly), Mem);
58 std::unique_ptr<MemoryBuffer> Buffer =
59 MemoryBuffer::getMemBuffer(Mem.str(), "test", false);
60 ErrorOr<std::unique_ptr<Module>> ModuleOrErr =
61 getLazyBitcodeModule(std::move(Buffer), Context);
62 return std::move(ModuleOrErr.get());
63 }
64
65 class BufferDataStreamer : public DataStreamer {
66 std::unique_ptr<MemoryBuffer> Buffer;
67 unsigned Pos = 0;
GetBytes(unsigned char * Out,size_t Len)68 size_t GetBytes(unsigned char *Out, size_t Len) override {
69 StringRef Buf = Buffer->getBuffer();
70 size_t Left = Buf.size() - Pos;
71 Len = std::min(Left, Len);
72 memcpy(Out, Buffer->getBuffer().substr(Pos).data(), Len);
73 Pos += Len;
74 return Len;
75 }
76
77 public:
BufferDataStreamer(std::unique_ptr<MemoryBuffer> Buffer)78 BufferDataStreamer(std::unique_ptr<MemoryBuffer> Buffer)
79 : Buffer(std::move(Buffer)) {}
80 };
81
82 static std::unique_ptr<Module>
getStreamedModuleFromAssembly(LLVMContext & Context,SmallString<1024> & Mem,const char * Assembly)83 getStreamedModuleFromAssembly(LLVMContext &Context, SmallString<1024> &Mem,
84 const char *Assembly) {
85 writeModuleToBuffer(parseAssembly(Context, Assembly), Mem);
86 std::unique_ptr<MemoryBuffer> Buffer =
87 MemoryBuffer::getMemBuffer(Mem.str(), "test", false);
88 auto Streamer = llvm::make_unique<BufferDataStreamer>(std::move(Buffer));
89 ErrorOr<std::unique_ptr<Module>> ModuleOrErr =
90 getStreamedBitcodeModule("test", std::move(Streamer), Context);
91 return std::move(ModuleOrErr.get());
92 }
93
94 // Checks if we correctly detect eof if we try to read N bits when there are not
95 // enough bits left on the input stream to read N bits, and we are using a data
96 // streamer. In particular, it checks if we properly set the object size when
97 // the eof is reached under such conditions.
TEST(BitReaderTest,TestForEofAfterReadFailureOnDataStreamer)98 TEST(BitReaderTest, TestForEofAfterReadFailureOnDataStreamer) {
99 // Note: Because StreamingMemoryObject does a call to method GetBytes in it's
100 // constructor, using internal constant kChunkSize, we must fill the input
101 // with more characters than that amount.
102 static size_t InputSize = StreamingMemoryObject::kChunkSize + 5;
103 char *Text = new char[InputSize];
104 std::memset(Text, 'a', InputSize);
105 Text[InputSize - 1] = '\0';
106 StringRef Input(Text);
107
108 // Build bitsteam reader using data streamer.
109 auto MemoryBuf = MemoryBuffer::getMemBuffer(Input);
110 std::unique_ptr<DataStreamer> Streamer(
111 new BufferDataStreamer(std::move(MemoryBuf)));
112 auto OwnedBytes =
113 llvm::make_unique<StreamingMemoryObject>(std::move(Streamer));
114 auto Reader = llvm::make_unique<BitstreamReader>(std::move(OwnedBytes));
115 BitstreamCursor Cursor;
116 Cursor.init(Reader.get());
117
118 // Jump to two bytes before end of stream.
119 Cursor.JumpToBit((InputSize - 4) * CHAR_BIT);
120 // Try to read 4 bytes when only 2 are present, resulting in error value 0.
121 const size_t ReadErrorValue = 0;
122 EXPECT_EQ(ReadErrorValue, Cursor.Read(32));
123 // Should be at eof now.
124 EXPECT_TRUE(Cursor.AtEndOfStream());
125
126 delete[] Text;
127 }
128
TEST(BitReaderTest,MateralizeForwardRefWithStream)129 TEST(BitReaderTest, MateralizeForwardRefWithStream) {
130 SmallString<1024> Mem;
131
132 LLVMContext Context;
133 std::unique_ptr<Module> M = getStreamedModuleFromAssembly(
134 Context, Mem, "@table = constant i8* blockaddress(@func, %bb)\n"
135 "define void @func() {\n"
136 " unreachable\n"
137 "bb:\n"
138 " unreachable\n"
139 "}\n");
140 EXPECT_FALSE(M->getFunction("func")->empty());
141 }
142
143 // Tests that lazy evaluation can parse functions out of order.
TEST(BitReaderTest,MaterializeFunctionsOutOfOrder)144 TEST(BitReaderTest, MaterializeFunctionsOutOfOrder) {
145 SmallString<1024> Mem;
146 LLVMContext Context;
147 std::unique_ptr<Module> M = getLazyModuleFromAssembly(
148 Context, Mem, "define void @f() {\n"
149 " unreachable\n"
150 "}\n"
151 "define void @g() {\n"
152 " unreachable\n"
153 "}\n"
154 "define void @h() {\n"
155 " unreachable\n"
156 "}\n"
157 "define void @j() {\n"
158 " unreachable\n"
159 "}\n");
160 EXPECT_FALSE(verifyModule(*M, &dbgs()));
161
162 Function *F = M->getFunction("f");
163 Function *G = M->getFunction("g");
164 Function *H = M->getFunction("h");
165 Function *J = M->getFunction("j");
166
167 // Initially all functions are not materialized (no basic blocks).
168 EXPECT_TRUE(F->empty());
169 EXPECT_TRUE(G->empty());
170 EXPECT_TRUE(H->empty());
171 EXPECT_TRUE(J->empty());
172 EXPECT_FALSE(verifyModule(*M, &dbgs()));
173
174 // Materialize h.
175 H->materialize();
176 EXPECT_TRUE(F->empty());
177 EXPECT_TRUE(G->empty());
178 EXPECT_FALSE(H->empty());
179 EXPECT_TRUE(J->empty());
180 EXPECT_FALSE(verifyModule(*M, &dbgs()));
181
182 // Materialize g.
183 G->materialize();
184 EXPECT_TRUE(F->empty());
185 EXPECT_FALSE(G->empty());
186 EXPECT_FALSE(H->empty());
187 EXPECT_TRUE(J->empty());
188 EXPECT_FALSE(verifyModule(*M, &dbgs()));
189
190 // Materialize j.
191 J->materialize();
192 EXPECT_TRUE(F->empty());
193 EXPECT_FALSE(G->empty());
194 EXPECT_FALSE(H->empty());
195 EXPECT_FALSE(J->empty());
196 EXPECT_FALSE(verifyModule(*M, &dbgs()));
197
198 // Materialize f.
199 F->materialize();
200 EXPECT_FALSE(F->empty());
201 EXPECT_FALSE(G->empty());
202 EXPECT_FALSE(H->empty());
203 EXPECT_FALSE(J->empty());
204 EXPECT_FALSE(verifyModule(*M, &dbgs()));
205 }
206
TEST(BitReaderTest,MaterializeFunctionsForBlockAddr)207 TEST(BitReaderTest, MaterializeFunctionsForBlockAddr) { // PR11677
208 SmallString<1024> Mem;
209
210 LLVMContext Context;
211 std::unique_ptr<Module> M = getLazyModuleFromAssembly(
212 Context, Mem, "@table = constant i8* blockaddress(@func, %bb)\n"
213 "define void @func() {\n"
214 " unreachable\n"
215 "bb:\n"
216 " unreachable\n"
217 "}\n");
218 EXPECT_FALSE(verifyModule(*M, &dbgs()));
219 }
220
TEST(BitReaderTest,MaterializeFunctionsForBlockAddrInFunctionBefore)221 TEST(BitReaderTest, MaterializeFunctionsForBlockAddrInFunctionBefore) {
222 SmallString<1024> Mem;
223
224 LLVMContext Context;
225 std::unique_ptr<Module> M = getLazyModuleFromAssembly(
226 Context, Mem, "define i8* @before() {\n"
227 " ret i8* blockaddress(@func, %bb)\n"
228 "}\n"
229 "define void @other() {\n"
230 " unreachable\n"
231 "}\n"
232 "define void @func() {\n"
233 " unreachable\n"
234 "bb:\n"
235 " unreachable\n"
236 "}\n");
237 EXPECT_TRUE(M->getFunction("before")->empty());
238 EXPECT_TRUE(M->getFunction("func")->empty());
239 EXPECT_FALSE(verifyModule(*M, &dbgs()));
240
241 // Materialize @before, pulling in @func.
242 EXPECT_FALSE(M->getFunction("before")->materialize());
243 EXPECT_FALSE(M->getFunction("func")->empty());
244 EXPECT_TRUE(M->getFunction("other")->empty());
245 EXPECT_FALSE(verifyModule(*M, &dbgs()));
246 }
247
TEST(BitReaderTest,MaterializeFunctionsForBlockAddrInFunctionAfter)248 TEST(BitReaderTest, MaterializeFunctionsForBlockAddrInFunctionAfter) {
249 SmallString<1024> Mem;
250
251 LLVMContext Context;
252 std::unique_ptr<Module> M = getLazyModuleFromAssembly(
253 Context, Mem, "define void @func() {\n"
254 " unreachable\n"
255 "bb:\n"
256 " unreachable\n"
257 "}\n"
258 "define void @other() {\n"
259 " unreachable\n"
260 "}\n"
261 "define i8* @after() {\n"
262 " ret i8* blockaddress(@func, %bb)\n"
263 "}\n");
264 EXPECT_TRUE(M->getFunction("after")->empty());
265 EXPECT_TRUE(M->getFunction("func")->empty());
266 EXPECT_FALSE(verifyModule(*M, &dbgs()));
267
268 // Materialize @after, pulling in @func.
269 EXPECT_FALSE(M->getFunction("after")->materialize());
270 EXPECT_FALSE(M->getFunction("func")->empty());
271 EXPECT_TRUE(M->getFunction("other")->empty());
272 EXPECT_FALSE(verifyModule(*M, &dbgs()));
273 }
274
275 } // end namespace
276