xref: /freebsd/contrib/llvm-project/llvm/lib/Bitcode/Reader/BitReader.cpp (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 //===-- BitReader.cpp -----------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "llvm-c/BitReader.h"
10 #include "llvm-c/Core.h"
11 #include "llvm/Bitcode/BitcodeReader.h"
12 #include "llvm/IR/LLVMContext.h"
13 #include "llvm/IR/Module.h"
14 #include "llvm/Support/MemoryBuffer.h"
15 #include "llvm/Support/raw_ostream.h"
16 #include <cstring>
17 #include <string>
18 
19 using namespace llvm;
20 
21 /* Builds a module from the bitcode in the specified memory buffer, returning a
22    reference to the module via the OutModule parameter. Returns 0 on success.
23    Optionally returns a human-readable error message via OutMessage. */
24 LLVMBool LLVMParseBitcode(LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutModule,
25                           char **OutMessage) {
26   return LLVMParseBitcodeInContext(LLVMGetGlobalContext(), MemBuf, OutModule,
27                                    OutMessage);
28 }
29 
30 LLVMBool LLVMParseBitcode2(LLVMMemoryBufferRef MemBuf,
31                            LLVMModuleRef *OutModule) {
32   return LLVMParseBitcodeInContext2(LLVMGetGlobalContext(), MemBuf, OutModule);
33 }
34 
35 LLVMBool LLVMParseBitcodeInContext(LLVMContextRef ContextRef,
36                                    LLVMMemoryBufferRef MemBuf,
37                                    LLVMModuleRef *OutModule,
38                                    char **OutMessage) {
39   MemoryBufferRef Buf = unwrap(MemBuf)->getMemBufferRef();
40   LLVMContext &Ctx = *unwrap(ContextRef);
41 
42   Expected<std::unique_ptr<Module>> ModuleOrErr = parseBitcodeFile(Buf, Ctx);
43   if (Error Err = ModuleOrErr.takeError()) {
44     std::string Message;
45     handleAllErrors(std::move(Err), [&](ErrorInfoBase &EIB) {
46       Message = EIB.message();
47     });
48     if (OutMessage)
49       *OutMessage = strdup(Message.c_str());
50     *OutModule = wrap((Module *)nullptr);
51     return 1;
52   }
53 
54   *OutModule = wrap(ModuleOrErr.get().release());
55   return 0;
56 }
57 
58 LLVMBool LLVMParseBitcodeInContext2(LLVMContextRef ContextRef,
59                                     LLVMMemoryBufferRef MemBuf,
60                                     LLVMModuleRef *OutModule) {
61   MemoryBufferRef Buf = unwrap(MemBuf)->getMemBufferRef();
62   LLVMContext &Ctx = *unwrap(ContextRef);
63 
64   ErrorOr<std::unique_ptr<Module>> ModuleOrErr =
65       expectedToErrorOrAndEmitErrors(Ctx, parseBitcodeFile(Buf, Ctx));
66   if (ModuleOrErr.getError()) {
67     *OutModule = wrap((Module *)nullptr);
68     return 1;
69   }
70 
71   *OutModule = wrap(ModuleOrErr.get().release());
72   return 0;
73 }
74 
75 /* Reads a module from the specified path, returning via the OutModule parameter
76    a module provider which performs lazy deserialization. Returns 0 on success.
77    Optionally returns a human-readable error message via OutMessage. */
78 LLVMBool LLVMGetBitcodeModuleInContext(LLVMContextRef ContextRef,
79                                        LLVMMemoryBufferRef MemBuf,
80                                        LLVMModuleRef *OutM, char **OutMessage) {
81   LLVMContext &Ctx = *unwrap(ContextRef);
82   std::unique_ptr<MemoryBuffer> Owner(unwrap(MemBuf));
83   Expected<std::unique_ptr<Module>> ModuleOrErr =
84       getOwningLazyBitcodeModule(std::move(Owner), Ctx);
85   // Release the buffer if we didn't take ownership of it since we never owned
86   // it anyway.
87   (void)Owner.release();
88 
89   if (Error Err = ModuleOrErr.takeError()) {
90     std::string Message;
91     handleAllErrors(std::move(Err), [&](ErrorInfoBase &EIB) {
92       Message = EIB.message();
93     });
94     if (OutMessage)
95       *OutMessage = strdup(Message.c_str());
96     *OutM = wrap((Module *)nullptr);
97     return 1;
98   }
99 
100   *OutM = wrap(ModuleOrErr.get().release());
101 
102   return 0;
103 }
104 
105 LLVMBool LLVMGetBitcodeModuleInContext2(LLVMContextRef ContextRef,
106                                         LLVMMemoryBufferRef MemBuf,
107                                         LLVMModuleRef *OutM) {
108   LLVMContext &Ctx = *unwrap(ContextRef);
109   std::unique_ptr<MemoryBuffer> Owner(unwrap(MemBuf));
110 
111   ErrorOr<std::unique_ptr<Module>> ModuleOrErr = expectedToErrorOrAndEmitErrors(
112       Ctx, getOwningLazyBitcodeModule(std::move(Owner), Ctx));
113   Owner.release();
114 
115   if (ModuleOrErr.getError()) {
116     *OutM = wrap((Module *)nullptr);
117     return 1;
118   }
119 
120   *OutM = wrap(ModuleOrErr.get().release());
121   return 0;
122 }
123 
124 LLVMBool LLVMGetBitcodeModule(LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutM,
125                               char **OutMessage) {
126   return LLVMGetBitcodeModuleInContext(LLVMGetGlobalContext(), MemBuf, OutM,
127                                        OutMessage);
128 }
129 
130 LLVMBool LLVMGetBitcodeModule2(LLVMMemoryBufferRef MemBuf,
131                                LLVMModuleRef *OutM) {
132   return LLVMGetBitcodeModuleInContext2(LLVMGetGlobalContext(), MemBuf, OutM);
133 }
134