1 #include "llvm/Bitcode/BitcodeReader.h"
2 #include "llvm/Bitcode/BitcodeWriter.h"
3 #include "llvm/IR/Function.h"
4 #include "llvm/IR/GlobalVariable.h"
5 #include "llvm/IR/LLVMContext.h"
6 #include "llvm/IR/Module.h"
7 #include "llvm/Support/CommandLine.h"
8 #include "llvm/Support/ManagedStatic.h"
9 #include "llvm/Support/MemoryBuffer.h"
10 #include "llvm/Support/FileSystem.h"
11 #include "llvm/Support/raw_ostream.h"
12 #include "llvm/Support/ErrorOr.h"
13 #include "llvm/Support/ToolOutputFile.h"
14 #include "llvm/Config/llvm-config.h"
15 
16 #include <system_error>
17 
18 using namespace llvm;
19 
20 static cl::opt<std::string>
21 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
22 
23 static cl::opt<std::string>
24 OutputFilename("o", cl::desc("Output filename"),
25                cl::value_desc("filename"));
26 
27 int main(int argc, char **argv) {
28   LLVMContext Context;
29   llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
30 
31   cl::ParseCommandLineOptions(argc, argv, "libclc builtin preparation tool\n");
32 
33   std::string ErrorMessage;
34   Module *M = nullptr;
35 
36   {
37     ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
38       MemoryBuffer::getFile(InputFilename);
39     if (std::error_code  ec = BufferOrErr.getError()) {
40       ErrorMessage = ec.message();
41     } else {
42       std::unique_ptr<MemoryBuffer> &BufferPtr = BufferOrErr.get();
43       ErrorOr<std::unique_ptr<Module>> ModuleOrErr =
44           expectedToErrorOrAndEmitErrors(Context,
45           parseBitcodeFile(BufferPtr.get()->getMemBufferRef(), Context));
46       if (std::error_code ec = ModuleOrErr.getError())
47         ErrorMessage = ec.message();
48 
49       M = ModuleOrErr.get().release();
50     }
51   }
52 
53   if (!M) {
54     errs() << argv[0] << ": ";
55     if (ErrorMessage.size())
56       errs() << ErrorMessage << "\n";
57     else
58       errs() << "bitcode didn't read correctly.\n";
59     return 1;
60   }
61 
62   // Strip the OpenCL version metadata. There are a lot of linked
63   // modules in the library build, each spamming the same
64   // version. This may also report a different version than the user
65   // program is using. This should probably be uniqued when linking.
66   if (NamedMDNode *OCLVersion = M->getNamedMetadata("opencl.ocl.version"))
67       M->eraseNamedMetadata(OCLVersion);
68 
69   // Set linkage of every external definition to linkonce_odr.
70   for (Module::iterator i = M->begin(), e = M->end(); i != e; ++i) {
71     if (!i->isDeclaration() && i->getLinkage() == GlobalValue::ExternalLinkage)
72       i->setLinkage(GlobalValue::LinkOnceODRLinkage);
73   }
74 
75   for (Module::global_iterator i = M->global_begin(), e = M->global_end();
76        i != e; ++i) {
77     if (!i->isDeclaration() && i->getLinkage() == GlobalValue::ExternalLinkage)
78       i->setLinkage(GlobalValue::LinkOnceODRLinkage);
79   }
80 
81   if (OutputFilename.empty()) {
82     errs() << "no output file\n";
83     return 1;
84   }
85 
86   std::error_code EC;
87   std::unique_ptr<tool_output_file> Out
88   (new tool_output_file(OutputFilename, EC, sys::fs::F_None));
89   if (EC) {
90     errs() << EC.message() << '\n';
91     exit(1);
92   }
93 
94   WriteBitcodeToFile(M, Out->os());
95 
96   // Declare success.
97   Out->keep();
98   return 0;
99 }
100 
101