It's not necessary to do rounding for alloca operations when the requested
alignment is equal to the stack alignment.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40004 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/lli/lli.cpp b/tools/lli/lli.cpp
new file mode 100644
index 0000000..3ce2807
--- /dev/null
+++ b/tools/lli/lli.cpp
@@ -0,0 +1,160 @@
+//===- lli.cpp - LLVM Interpreter / Dynamic compiler ----------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This utility provides a simple wrapper around the LLVM Execution Engines,
+// which allow the direct execution of LLVM programs through a Just-In-Time
+// compiler, or through an intepreter if no JIT is available for this platform.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Module.h"
+#include "llvm/ModuleProvider.h"
+#include "llvm/Type.h"
+#include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/CodeGen/LinkAllCodegenComponents.h"
+#include "llvm/ExecutionEngine/JIT.h"
+#include "llvm/ExecutionEngine/Interpreter.h"
+#include "llvm/ExecutionEngine/GenericValue.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/ManagedStatic.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/PluginLoader.h"
+#include "llvm/System/Process.h"
+#include "llvm/System/Signals.h"
+#include <iostream>
+#include <cerrno>
+using namespace llvm;
+
+namespace {
+  cl::opt<std::string>
+  InputFile(cl::desc("<input bitcode>"), cl::Positional, cl::init("-"));
+
+  cl::list<std::string>
+  InputArgv(cl::ConsumeAfter, cl::desc("<program arguments>..."));
+
+  cl::opt<bool> ForceInterpreter("force-interpreter",
+                                 cl::desc("Force interpretation: disable JIT"),
+                                 cl::init(false));
+  cl::opt<std::string>
+  TargetTriple("mtriple", cl::desc("Override target triple for module"));
+  
+  cl::opt<std::string>
+  FakeArgv0("fake-argv0",
+            cl::desc("Override the 'argv[0]' value passed into the executing"
+                     " program"), cl::value_desc("executable"));
+  
+  cl::opt<bool>
+  DisableCoreFiles("disable-core-files", cl::Hidden,
+                   cl::desc("Disable emission of core files if possible"));
+}
+
+static ExecutionEngine *EE = 0;
+
+static void do_shutdown() {
+  delete EE;
+  llvm_shutdown();
+}
+
+//===----------------------------------------------------------------------===//
+// main Driver function
+//
+int main(int argc, char **argv, char * const *envp) {
+  atexit(do_shutdown);  // Call llvm_shutdown() on exit.
+  cl::ParseCommandLineOptions(argc, argv,
+                              " llvm interpreter & dynamic compiler\n");
+  sys::PrintStackTraceOnErrorSignal();
+
+  // If the user doesn't want core files, disable them.
+  if (DisableCoreFiles)
+    sys::Process::PreventCoreFiles();
+  
+  // Load the bitcode...
+  std::string ErrorMsg;
+  ModuleProvider *MP = 0;
+  if (MemoryBuffer *Buffer = MemoryBuffer::getFileOrSTDIN(InputFile,&ErrorMsg)){
+    MP = getBitcodeModuleProvider(Buffer, &ErrorMsg);
+    if (!MP) delete Buffer;
+  }
+  
+  if (!MP) {
+    std::cerr << argv[0] << ": error loading program '" << InputFile << "': "
+              << ErrorMsg << "\n";
+    exit(1);
+  }
+
+  // Get the module as the MP could go away once EE takes over.
+  Module *Mod = MP->getModule();
+
+  // If we are supposed to override the target triple, do so now.
+  if (!TargetTriple.empty())
+    Mod->setTargetTriple(TargetTriple);
+  
+  EE = ExecutionEngine::create(MP, ForceInterpreter, &ErrorMsg);
+  if (!EE && !ErrorMsg.empty()) {
+    std::cerr << argv[0] << ":error creating EE: " << ErrorMsg << "\n";
+    exit(1);
+  }
+
+  // If the user specifically requested an argv[0] to pass into the program,
+  // do it now.
+  if (!FakeArgv0.empty()) {
+    InputFile = FakeArgv0;
+  } else {
+    // Otherwise, if there is a .bc suffix on the executable strip it off, it
+    // might confuse the program.
+    if (InputFile.rfind(".bc") == InputFile.length() - 3)
+      InputFile.erase(InputFile.length() - 3);
+  }
+
+  // Add the module's name to the start of the vector of arguments to main().
+  InputArgv.insert(InputArgv.begin(), InputFile);
+
+  // Call the main function from M as if its signature were:
+  //   int main (int argc, char **argv, const char **envp)
+  // using the contents of Args to determine argc & argv, and the contents of
+  // EnvVars to determine envp.
+  //
+  Function *Fn = Mod->getFunction("main");
+  if (!Fn) {
+    std::cerr << "'main' function not found in module.\n";
+    return -1;
+  }
+
+  // If the program doesn't explicitly call exit, we will need the Exit 
+  // function later on to make an explicit call, so get the function now. 
+  Constant *Exit = Mod->getOrInsertFunction("exit", Type::VoidTy,
+                                                        Type::Int32Ty, NULL);
+  
+  // Reset errno to zero on entry to main.
+  errno = 0;
+ 
+  // Run static constructors.
+  EE->runStaticConstructorsDestructors(false);
+  
+  // Run main.
+  int Result = EE->runFunctionAsMain(Fn, InputArgv, envp);
+
+  // Run static destructors.
+  EE->runStaticConstructorsDestructors(true);
+  
+  // If the program didn't call exit explicitly, we should call it now. 
+  // This ensures that any atexit handlers get called correctly.
+  if (Function *ExitF = dyn_cast<Function>(Exit)) {
+    std::vector<GenericValue> Args;
+    GenericValue ResultGV;
+    ResultGV.IntVal = APInt(32, Result);
+    Args.push_back(ResultGV);
+    EE->runFunction(ExitF, Args);
+    std::cerr << "ERROR: exit(" << Result << ") returned!\n";
+    abort();
+  } else {
+    std::cerr << "ERROR: exit defined with wrong prototype!\n";
+    abort();
+  }
+}