//
// The LLVM Compiler Infrastructure
//
-// This file was developed by Devang Patel and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
-// This file implementes link time optimization library. This library is
+// This file implements the Link Time Optimization library. This library is
// intended to be used by linker to optimize code at link time.
//
//===----------------------------------------------------------------------===//
-#include "llvm/Module.h"
-#include "llvm/PassManager.h"
-#include "llvm/Linker.h"
-#include "llvm/Constants.h"
-#include "llvm/DerivedTypes.h"
-#include "llvm/SymbolTable.h"
-#include "llvm/Bytecode/Reader.h"
-#include "llvm/Bytecode/Writer.h"
-#include "llvm/Support/CommandLine.h"
-#include "llvm/Support/FileUtilities.h"
-#include "llvm/Support/SystemUtils.h"
-#include "llvm/Support/Mangler.h"
-#include "llvm/System/Program.h"
-#include "llvm/System/Signals.h"
-#include "llvm/Analysis/Passes.h"
-#include "llvm/Analysis/Verifier.h"
-#include "llvm/Target/SubtargetFeature.h"
-#include "llvm/Target/TargetData.h"
-#include "llvm/Target/TargetMachine.h"
-#include "llvm/Target/TargetMachineRegistry.h"
-#include "llvm/Transforms/IPO.h"
-#include "llvm/Transforms/Scalar.h"
-#include "llvm/Analysis/LoadValueNumbering.h"
-#include "llvm/LinkTimeOptimizer.h"
-#include <fstream>
-#include <iostream>
-
-using namespace llvm;
-
-extern "C"
-llvm::LinkTimeOptimizer *createLLVMOptimizer()
+#include "llvm-c/lto.h"
+#include "llvm-c/Core.h"
+
+#include "LTOModule.h"
+#include "LTOCodeGenerator.h"
+
+
+// holds most recent error string
+// *** not thread safe ***
+static std::string sLastErrorString;
+
+
+
+//
+// returns a printable string
+//
+extern const char* lto_get_version()
+{
+ return LTOCodeGenerator::getVersionString();
+}
+
+//
+// returns the last error string or NULL if last operation was successful
+//
+const char* lto_get_error_message()
+{
+ return sLastErrorString.c_str();
+}
+
+
+
+//
+// validates if a file is a loadable object file
+//
+bool lto_module_is_object_file(const char* path)
+{
+ return LTOModule::isBitcodeFile(path);
+}
+
+
+//
+// validates if a file is a loadable object file compilable for requested target
+//
+bool lto_module_is_object_file_for_target(const char* path,
+ const char* target_triplet_prefix)
+{
+ return LTOModule::isBitcodeFileForTarget(path, target_triplet_prefix);
+}
+
+
+//
+// validates if a buffer is a loadable object file
+//
+bool lto_module_is_object_file_in_memory(const void* mem, size_t length)
+{
+ return LTOModule::isBitcodeFile(mem, length);
+}
+
+
+//
+// validates if a buffer is a loadable object file compilable for the target
+//
+bool lto_module_is_object_file_in_memory_for_target(const void* mem,
+ size_t length, const char* target_triplet_prefix)
{
- llvm::LinkTimeOptimizer *l = new llvm::LinkTimeOptimizer();
- return l;
+ return LTOModule::isBitcodeFileForTarget(mem, length, target_triplet_prefix);
}
-/// If symbol is not used then make it internal and let optimizer takes
-/// care of it.
-void LLVMSymbol::mayBeNotUsed() {
- gv->setLinkage(GlobalValue::InternalLinkage);
+//
+// loads an object file from disk
+// returns NULL on error (check lto_get_error_message() for details)
+//
+lto_module_t lto_module_create(const char* path)
+{
+ return LTOModule::makeLTOModule(path, sLastErrorString);
}
-// Helper routine
-// FIXME : Take advantage of GlobalPrefix from AsmPrinter
-static const char *addUnderscore(const char *name) {
- size_t namelen = strlen(name);
- char *symName = (char*)malloc(namelen+2);
- symName[0] = '_';
- strcpy(&symName[1], name);
- return symName;
+
+//
+// loads an object file from memory
+// returns NULL on error (check lto_get_error_message() for details)
+//
+lto_module_t lto_module_create_from_memory(const void* mem, size_t length)
+{
+ return LTOModule::makeLTOModule(mem, length, sLastErrorString);
}
-// Map LLVM LinkageType to LTO LinakgeType
-static LTOLinkageTypes
-getLTOLinkageType(GlobalValue *v)
+
+//
+// frees all memory for a module
+// upon return the lto_module_t is no longer valid
+//
+void lto_module_dispose(lto_module_t mod)
{
- LTOLinkageTypes lt;
- if (v->hasExternalLinkage())
- lt = LTOExternalLinkage;
- else if (v->hasLinkOnceLinkage())
- lt = LTOLinkOnceLinkage;
- else if (v->hasWeakLinkage())
- lt = LTOWeakLinkage;
- else
- // Otherwise it is internal linkage for link time optimizer
- lt = LTOInternalLinkage;
- return lt;
+ delete mod;
}
-// Find exeternal symbols referenced by VALUE. This is a recursive function.
-static void
-findExternalRefs(Value *value, std::set<std::string> &references,
- Mangler &mangler) {
-
- if (GlobalValue *gv = dyn_cast<GlobalValue>(value)) {
- LTOLinkageTypes lt = getLTOLinkageType(gv);
- if (lt != LTOInternalLinkage && strncmp (gv->getName().c_str(), "llvm.", 5))
- references.insert(mangler.getValueName(gv));
- }
- else if (Constant *c = dyn_cast<Constant>(value))
- // Handle ConstantExpr, ConstantStruct, ConstantArry etc..
- for (unsigned i = 0, e = c->getNumOperands(); i != e; ++i)
- findExternalRefs(c->getOperand(i), references, mangler);
+
+//
+// returns triplet string which the object module was compiled under
+//
+const char* lto_module_get_target_triple(lto_module_t mod)
+{
+ return mod->getTargetTriple();
}
-/// InputFilename is a LLVM bytecode file. Read it using bytecode reader.
-/// Collect global functions and symbol names in symbols vector.
-/// Collect external references in references vector.
-/// Return LTO_READ_SUCCESS if there is no error.
-enum LTOStatus
-LinkTimeOptimizer::readLLVMObjectFile(const std::string &InputFilename,
- NameToSymbolMap &symbols,
- std::set<std::string> &references)
+
+//
+// returns the number of symbols in the object module
+//
+uint32_t lto_module_get_num_symbols(lto_module_t mod)
{
- Module *m = ParseBytecodeFile(InputFilename);
- if (!m)
- return LTO_READ_FAILURE;
-
- // Use mangler to add GlobalPrefix to names to match linker names.
- // FIXME : Instead of hard coding "-" use GlobalPrefix.
- Mangler mangler(*m, "_");
-
- modules.push_back(m);
-
- for (Module::iterator f = m->begin(), e = m->end(); f != e; ++f) {
-
- LTOLinkageTypes lt = getLTOLinkageType(f);
-
- if (!f->isExternal() && lt != LTOInternalLinkage
- && strncmp (f->getName().c_str(), "llvm.", 5)) {
- LLVMSymbol *newSymbol = new LLVMSymbol(lt, f, f->getName(),
- mangler.getValueName(f));
- symbols[newSymbol->getMangledName()] = newSymbol;
- allSymbols[newSymbol->getMangledName()] = newSymbol;
- }
-
- // Collect external symbols referenced by this function.
- for (Function::iterator b = f->begin(), fe = f->end(); b != fe; ++b)
- for (BasicBlock::iterator i = b->begin(), be = b->end();
- i != be; ++i)
- for (unsigned count = 0, total = i->getNumOperands();
- count != total; ++count)
- findExternalRefs(i->getOperand(count), references, mangler);
- }
-
- for (Module::global_iterator v = m->global_begin(), e = m->global_end();
- v != e; ++v) {
- LTOLinkageTypes lt = getLTOLinkageType(v);
- if (!v->isExternal() && lt != LTOInternalLinkage
- && strncmp (v->getName().c_str(), "llvm.", 5)) {
- LLVMSymbol *newSymbol = new LLVMSymbol(lt, v, v->getName(),
- mangler.getValueName(v));
- symbols[newSymbol->getMangledName()] = newSymbol;
-
- for (unsigned count = 0, total = v->getNumOperands();
- count != total; ++count)
- findExternalRefs(v->getOperand(count), references, mangler);
-
- }
- }
-
- return LTO_READ_SUCCESS;
+ return mod->getSymbolCount();
}
-/// Optimize module M using various IPO passes. Use exportList to
-/// internalize selected symbols. Target platform is selected
-/// based on information available to module M. No new target
-/// features are selected.
-static enum LTOStatus lto_optimize(Module *M, std::ostream &Out,
- std::vector<const char *> &exportList)
+//
+// returns the name of the ith symbol in the object module
+//
+const char* lto_module_get_symbol_name(lto_module_t mod, uint32_t index)
{
- // Instantiate the pass manager to organize the passes.
- PassManager Passes;
-
- // Collect Target info
- std::string Err;
- const TargetMachineRegistry::Entry* March =
- TargetMachineRegistry::getClosestStaticTargetForModule(*M, Err);
-
- if (March == 0)
- return LTO_NO_TARGET;
-
- // Create target
- std::string Features;
- std::auto_ptr<TargetMachine> target(March->CtorFn(*M, Features));
- if (!target.get())
- return LTO_NO_TARGET;
-
- TargetMachine &Target = *target.get();
-
- // Start off with a verification pass.
- Passes.add(createVerifierPass());
-
- // Add an appropriate TargetData instance for this module...
- Passes.add(new TargetData(*Target.getTargetData()));
-
- // Often if the programmer does not specify proper prototypes for the
- // functions they are calling, they end up calling a vararg version of the
- // function that does not get a body filled in (the real function has typed
- // arguments). This pass merges the two functions.
- Passes.add(createFunctionResolvingPass());
-
- // Internalize symbols if export list is nonemty
- if (!exportList.empty())
- Passes.add(createInternalizePass(exportList));
-
- // Now that we internalized some globals, see if we can hack on them!
- Passes.add(createGlobalOptimizerPass());
-
- // Linking modules together can lead to duplicated global constants, only
- // keep one copy of each constant...
- Passes.add(createConstantMergePass());
-
- // If the -s command line option was specified, strip the symbols out of the
- // resulting program to make it smaller. -s is a GLD option that we are
- // supporting.
- Passes.add(createStripSymbolsPass());
-
- // Propagate constants at call sites into the functions they call.
- Passes.add(createIPConstantPropagationPass());
-
- // Remove unused arguments from functions...
- Passes.add(createDeadArgEliminationPass());
-
- Passes.add(createFunctionInliningPass()); // Inline small functions
-
- Passes.add(createPruneEHPass()); // Remove dead EH info
-
- Passes.add(createGlobalDCEPass()); // Remove dead functions
-
- // If we didn't decide to inline a function, check to see if we can
- // transform it to pass arguments by value instead of by reference.
- Passes.add(createArgumentPromotionPass());
-
- // The IPO passes may leave cruft around. Clean up after them.
- Passes.add(createInstructionCombiningPass());
-
- Passes.add(createScalarReplAggregatesPass()); // Break up allocas
-
- // Run a few AA driven optimizations here and now, to cleanup the code.
- Passes.add(createGlobalsModRefPass()); // IP alias analysis
-
- Passes.add(createLICMPass()); // Hoist loop invariants
- Passes.add(createLoadValueNumberingPass()); // GVN for load instrs
- Passes.add(createGCSEPass()); // Remove common subexprs
- Passes.add(createDeadStoreEliminationPass()); // Nuke dead stores
-
- // Cleanup and simplify the code after the scalar optimizations.
- Passes.add(createInstructionCombiningPass());
-
- // Delete basic blocks, which optimization passes may have killed...
- Passes.add(createCFGSimplificationPass());
-
- // Now that we have optimized the program, discard unreachable functions...
- Passes.add(createGlobalDCEPass());
-
- // Make sure everything is still good.
- Passes.add(createVerifierPass());
-
- Target.addPassesToEmitFile(Passes, Out, TargetMachine::AssemblyFile, true);
-
- // Run our queue of passes all at once now, efficiently.
- Passes.run(*M);
-
- return LTO_OPT_SUCCESS;
+ return mod->getSymbolName(index);
}
-///Link all modules together and optimize them using IPO. Generate
-/// native object file using OutputFilename
-/// Return appropriate LTOStatus.
-enum LTOStatus
-LinkTimeOptimizer::optimizeModules(const std::string &OutputFilename,
- std::vector<const char *> &exportList)
+
+//
+// returns the attributes of the ith symbol in the object module
+//
+lto_symbol_attributes lto_module_get_symbol_attribute(lto_module_t mod,
+ uint32_t index)
+{
+ return mod->getSymbolAttributes(index);
+}
+
+
+
+
+
+//
+// instantiates a code generator
+// returns NULL if there is an error
+//
+lto_code_gen_t lto_codegen_create(void)
+{
+ return new LTOCodeGenerator();
+}
+
+
+
+//
+// frees all memory for a code generator
+// upon return the lto_code_gen_t is no longer valid
+//
+void lto_codegen_dispose(lto_code_gen_t cg)
+{
+ delete cg;
+}
+
+
+
+//
+// add an object module to the set of modules for which code will be generated
+// returns true on error (check lto_get_error_message() for details)
+//
+bool lto_codegen_add_module(lto_code_gen_t cg, lto_module_t mod)
+{
+ return cg->addModule(mod, sLastErrorString);
+}
+
+
+//
+// sets what if any format of debug info should be generated
+// returns true on error (check lto_get_error_message() for details)
+//
+bool lto_codegen_set_debug_model(lto_code_gen_t cg, lto_debug_model debug)
+{
+ return cg->setDebugInfo(debug, sLastErrorString);
+}
+
+
+//
+// sets what code model to generated
+// returns true on error (check lto_get_error_message() for details)
+//
+bool lto_codegen_set_pic_model(lto_code_gen_t cg, lto_codegen_model model)
+{
+ return cg->setCodePICModel(model, sLastErrorString);
+}
+
+//
+// sets the path to the assembler tool
+//
+void lto_codegen_set_assembler_path(lto_code_gen_t cg, const char* path)
+{
+ cg->setAssemblerPath(path);
+}
+
+//
+// adds to a list of all global symbols that must exist in the final
+// generated code. If a function is not listed there, it might be
+// inlined into every usage and optimized away.
+//
+void lto_codegen_add_must_preserve_symbol(lto_code_gen_t cg, const char* symbol)
+{
+ cg->addMustPreserveSymbol(symbol);
+}
+
+
+//
+// writes a new file at the specified path that contains the
+// merged contents of all modules added so far.
+// returns true on error (check lto_get_error_message() for details)
+//
+bool lto_codegen_write_merged_modules(lto_code_gen_t cg, const char* path)
+{
+ return cg->writeMergedModules(path, sLastErrorString);
+}
+
+
+//
+// Generates code for all added modules into one native object file.
+// On sucess returns a pointer to a generated mach-o/ELF buffer and
+// length set to the buffer size. The buffer is owned by the
+// lto_code_gen_t and will be freed when lto_codegen_dispose()
+// is called, or lto_codegen_compile() is called again.
+// On failure, returns NULL (check lto_get_error_message() for details).
+//
+extern const void*
+lto_codegen_compile(lto_code_gen_t cg, size_t* length)
+{
+ return cg->compile(length, sLastErrorString);
+}
+
+
+//
+// Used to pass extra options to the code generator
+//
+extern void
+lto_codegen_debug_options(lto_code_gen_t cg, const char * opt)
{
- if (modules.empty())
- return LTO_NO_WORK;
-
- std::ios::openmode io_mode =
- std::ios::out | std::ios::trunc | std::ios::binary;
- std::string *errMsg = NULL;
- Module *bigOne = modules[0];
- Linker theLinker("LinkTimeOptimizer", bigOne, false);
- for (unsigned i = 1, e = modules.size(); i != e; ++i)
- if (theLinker.LinkModules(bigOne, modules[i], errMsg))
- return LTO_MODULE_MERGE_FAILURE;
-
-#if 0
- // Enable this when -save-temps is used
- std::ofstream Out("big.bc", io_mode);
- WriteBytecodeToFile(bigOne, Out, true);
-#endif
-
- // Strip leading underscore because it was added to match names
- // seen by linker.
- for (unsigned i = 0, e = exportList.size(); i != e; ++i) {
- const char *name = exportList[i];
- if (strlen(name) > 2 && name[0] == '_')
- exportList[i] = &name[1];
- }
-
- sys::Path tmpAsmFilePath("/tmp/");
- tmpAsmFilePath.createTemporaryFileOnDisk();
- sys::RemoveFileOnSignal(tmpAsmFilePath);
-
- std::ofstream asmFile(tmpAsmFilePath.c_str(), io_mode);
- if (!asmFile.is_open() || asmFile.bad()) {
- if (tmpAsmFilePath.exists())
- tmpAsmFilePath.eraseFromDisk();
- return LTO_WRITE_FAILURE;
- }
-
- enum LTOStatus status = lto_optimize(bigOne, asmFile, exportList);
- asmFile.close();
- if (status != LTO_OPT_SUCCESS) {
- tmpAsmFilePath.eraseFromDisk();
- return status;
- }
-
- // Run GCC to assemble and link the program into native code.
- //
- // Note:
- // We can't just assemble and link the file with the system assembler
- // and linker because we don't know where to put the _start symbol.
- // GCC mysteriously knows how to do it.
- const sys::Path gcc = FindExecutable("gcc", "/");
- if (gcc.isEmpty()) {
- tmpAsmFilePath.eraseFromDisk();
- return LTO_ASM_FAILURE;
- }
-
- std::vector<const char*> args;
- args.push_back(gcc.c_str());
- args.push_back("-c");
- args.push_back("-x");
- args.push_back("assembler");
- args.push_back("-o");
- args.push_back(OutputFilename.c_str());
- args.push_back(tmpAsmFilePath.c_str());
- args.push_back(0);
-
- sys::Program::ExecuteAndWait(gcc, &args[0], 0, 0, 1);
-
- tmpAsmFilePath.eraseFromDisk();
-
- return LTO_OPT_SUCCESS;
+ cg->setCodeGenDebugOptions(opt);
}