1 //===--- llvm-as.cpp - The low-level LLVM assembler -----------------------===//
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 //  This utility may be invoked in the following manner:
11 //   llvm-as --help         - Output information about command line switches
12 //   llvm-as [options]      - Read LLVM asm from stdin, write bitcode to stdout
13 //   llvm-as [options] x.ll - Read LLVM asm from the x.ll file, write bitcode
14 //                            to the x.bc file.
15 //
16 //===----------------------------------------------------------------------===//
17 
18 #include "llvm/IR/LLVMContext.h"
19 #include "llvm/IR/Verifier.h"
20 #include "llvm/AsmParser/Parser.h"
21 #include "llvm/Bitcode/ReaderWriter.h"
22 #include "llvm/IR/Module.h"
23 #include "llvm/Support/CommandLine.h"
24 #include "llvm/Support/FileSystem.h"
25 #include "llvm/Support/ManagedStatic.h"
26 #include "llvm/Support/PrettyStackTrace.h"
27 #include "llvm/Support/Signals.h"
28 #include "llvm/Support/SourceMgr.h"
29 #include "llvm/Support/SystemUtils.h"
30 #include "llvm/Support/ToolOutputFile.h"
31 
32 #include "slang_bitcode_gen.h"
33 #include "slang_version.h"
34 
35 #include "StripUnkAttr/strip_unknown_attributes.h"
36 
37 #include <memory>
38 using namespace llvm;
39 
40 static cl::opt<std::string>
41 InputFilename(cl::Positional, cl::desc("<input .llvm file>"), cl::init("-"));
42 
43 static cl::opt<std::string>
44 OutputFilename("o", cl::desc("Override output filename"),
45                cl::value_desc("filename"));
46 
47 static cl::opt<bool>
48 Force("f", cl::desc("Enable binary output on terminals"));
49 
50 static cl::opt<bool>
51 DisableOutput("disable-output", cl::desc("Disable output"), cl::init(false));
52 
53 static cl::opt<uint32_t>
54 TargetAPI("target-api", cl::desc("Specify RenderScript target API version "
55                                  "(0 = development API) (default is 0)"),
56           cl::init(0));
57 
58 static cl::opt<bool>
59 DumpAsm("d", cl::desc("Print assembly as parsed"), cl::Hidden);
60 
61 static cl::opt<bool>
62 DisableVerify("disable-verify", cl::Hidden,
63               cl::desc("Do not run verifier on input LLVM (dangerous!)"));
64 
stripUnknownAttributes(llvm::Module * M)65 static void stripUnknownAttributes(llvm::Module *M) {
66   for (llvm::Function &F : *M)
67     slang::stripUnknownAttributes(F);
68 }
69 
WriteOutputFile(const Module * M,uint32_t ModuleTargetAPI)70 static void WriteOutputFile(const Module *M, uint32_t ModuleTargetAPI) {
71   // Infer the output filename if needed.
72   if (OutputFilename.empty()) {
73     if (InputFilename == "-") {
74       OutputFilename = "-";
75     } else {
76       std::string IFN = InputFilename;
77       int Len = IFN.length();
78       if (IFN[Len-3] == '.' && IFN[Len-2] == 'l' && IFN[Len-1] == 'l') {
79         // Source ends in .ll
80         OutputFilename = std::string(IFN.begin(), IFN.end()-3);
81       } else {
82         OutputFilename = IFN;   // Append a .bc to it
83       }
84       OutputFilename += ".bc";
85     }
86   }
87 
88   std::error_code EC;
89   std::unique_ptr<tool_output_file> Out
90   (new tool_output_file(OutputFilename.c_str(), EC, llvm::sys::fs::F_None));
91   if (EC) {
92     // TODO(srhines): This isn't actually very specific and needs cleanup.
93     errs() << EC.message() << '\n';
94     exit(1);
95   }
96 
97   if (Force || !CheckBitcodeOutputToConsole(Out->os(), true)) {
98     slang::writeBitcode(Out->os(), *M,
99         /* TargetAPI = */ ModuleTargetAPI,
100         /* OptimizationLevel = */ 3,
101         /* GenerateDebugInfo = */ false);
102 
103     if (!Out->os().has_error()) {
104       // Declare success.
105       Out->keep();
106     }
107   }
108 }
109 
main(int argc,char ** argv)110 int main(int argc, char **argv) {
111   // Print a stack trace if we signal out.
112   sys::PrintStackTraceOnErrorSignal(argv[0]);
113   PrettyStackTraceProgram X(argc, argv);
114   LLVMContext Context;
115   llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
116   cl::ParseCommandLineOptions(argc, argv, "llvm .ll -> .bc assembler\n");
117 
118   // Check target API.
119   uint32_t ActualTargetAPI = (TargetAPI == 0) ? RS_DEVELOPMENT_API : TargetAPI;
120 
121   if (ActualTargetAPI != RS_DEVELOPMENT_API &&
122       (ActualTargetAPI < SLANG_MINIMUM_TARGET_API ||
123        ActualTargetAPI > SLANG_MAXIMUM_TARGET_API)) {
124     errs() << "target API level '" << ActualTargetAPI << "' is out of range "
125            << "('" << SLANG_MINIMUM_TARGET_API << "' - '"
126            << SLANG_MAXIMUM_TARGET_API << "')\n";
127     return 1;
128   }
129 
130   // Parse the file now...
131   SMDiagnostic Err;
132   std::unique_ptr<Module> M(parseAssemblyFile(InputFilename, Err, Context));
133   if (M.get() == 0) {
134     Err.print(argv[0], errs());
135     return 1;
136   }
137 
138   if (!DisableVerify) {
139     std::string Err;
140     raw_string_ostream stream(Err);
141     if (verifyModule(*M.get(), &stream)) {
142       errs() << argv[0]
143              << ": assembly parsed, but does not verify as correct!\n";
144       errs() << Err;
145       return 1;
146     }
147   }
148 
149   stripUnknownAttributes(M.get());
150 
151   if (DumpAsm) errs() << "Here's the assembly:\n" << *M.get();
152 
153   if (!DisableOutput)
154     WriteOutputFile(M.get(), ActualTargetAPI);
155 
156   return 0;
157 }
158