Fix FindExecutable to use sys::Path::GetMainExecutable instead of
just argv[0]. And remove the code for searching the current
working directory and for searching PATH; the point of FindExecutable
is not to find whatever version of the executable can be found by
searching around, but to find an executable that accompanies the
current executable.

Update the tools to use sys::Program::FindProgramByName when they
want PATH searching.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78240 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/llvm/Support/SystemUtils.h b/include/llvm/Support/SystemUtils.h
index 95124a0..69afd07 100644
--- a/include/llvm/Support/SystemUtils.h
+++ b/include/llvm/Support/SystemUtils.h
@@ -40,12 +40,12 @@
 );
 
 /// FindExecutable - Find a named executable, giving the argv[0] of program
-/// being executed. This allows us to find another LLVM tool if it is built into
-/// the same directory, but that directory is neither the current directory, nor
-/// in the PATH.  If the executable cannot be found, return an empty string.
+/// being executed. This allows us to find another LLVM tool if it is built in
+/// the same directory.  If the executable cannot be found, return an
+/// empty string.
 /// @brief Find a named executable.
 sys::Path FindExecutable(const std::string &ExeName,
-                         const std::string &ProgramPath);
+                         const char *Argv0, void *MainAddr);
 
 } // End llvm namespace
 
diff --git a/lib/Support/SystemUtils.cpp b/lib/Support/SystemUtils.cpp
index 49a87e4..09c0b19 100644
--- a/lib/Support/SystemUtils.cpp
+++ b/lib/Support/SystemUtils.cpp
@@ -50,24 +50,17 @@
 }
 
 /// FindExecutable - Find a named executable, giving the argv[0] of program
-/// being executed. This allows us to find another LLVM tool if it is built
-/// into the same directory, but that directory is neither the current
-/// directory, nor in the PATH.  If the executable cannot be found, return an
-/// empty string. Return the input string if given a full path to an executable.
-///
+/// being executed. This allows us to find another LLVM tool if it is built in
+/// the same directory.  If the executable cannot be found, return an
+/// empty string.
+/// @brief Find a named executable.
 #undef FindExecutable   // needed on windows :(
 sys::Path llvm::FindExecutable(const std::string &ExeName,
-                               const std::string &ProgramPath) {
-  // First check if the given name is already a valid path to an executable.
-  sys::Path Result(ExeName);
-  Result.makeAbsolute();
-  if (Result.canExecute())
-    return Result;
-
-  // Otherwise check the directory that the calling program is in.  We can do
+                               const char *Argv0, void *MainAddr) {
+  // Check the directory that the calling program is in.  We can do
   // this if ProgramPath contains at least one / character, indicating that it
   // is a relative path to the executable itself.
-  Result = ProgramPath;
+  sys::Path Result = sys::Path::GetMainExecutable(Argv0, MainAddr);
   Result.eraseComponent();
   if (!Result.isEmpty()) {
     Result.appendComponent(ExeName);
@@ -75,5 +68,5 @@
       return Result;
   }
 
-  return sys::Program::FindProgramByName(ExeName);
+  return sys::Path();
 }
diff --git a/tools/bugpoint/BugDriver.h b/tools/bugpoint/BugDriver.h
index 79c7038..5f4a130 100644
--- a/tools/bugpoint/BugDriver.h
+++ b/tools/bugpoint/BugDriver.h
@@ -44,7 +44,7 @@
 
 class BugDriver {
   LLVMContext& Context;
-  const std::string ToolName;  // Name of bugpoint
+  const char *ToolName;            // argv[0] of bugpoint
   std::string ReferenceOutputFile; // Name of `good' output file
   Module *Program;             // The raw program, linked together
   std::vector<const PassInfo*> PassesToRun;
@@ -64,7 +64,7 @@
   BugDriver(const char *toolname, bool as_child, bool find_bugs,
             unsigned timeout, unsigned memlimit, LLVMContext& ctxt);
 
-  const std::string &getToolName() const { return ToolName; }
+  const char *getToolName() const { return ToolName; }
 
   LLVMContext& getContext() { return Context; }
 
diff --git a/tools/bugpoint/ExecutionDriver.cpp b/tools/bugpoint/ExecutionDriver.cpp
index ceaf8f4..3916957 100644
--- a/tools/bugpoint/ExecutionDriver.cpp
+++ b/tools/bugpoint/ExecutionDriver.cpp
@@ -177,8 +177,7 @@
                                                  &ToolArgv, &GCCToolArgv);
     break;
   case Custom:
-    Interpreter = AbstractInterpreter::createCustom(getToolName(), Message,
-                                                    CustomExecCommand);
+    Interpreter = AbstractInterpreter::createCustom(Message, CustomExecCommand);
     break;
   default:
     Message = "Sorry, this back-end is not supported by bugpoint right now!\n";
@@ -200,7 +199,7 @@
         InterpreterSel == CBE_bug) {
       SafeInterpreterSel = RunLLC;
       SafeToolArgs.push_back("--relocation-model=pic");
-      SafeInterpreter = AbstractInterpreter::createLLC(Path, Message,
+      SafeInterpreter = AbstractInterpreter::createLLC(Path.c_str(), Message,
                                                        &SafeToolArgs,
                                                        &GCCToolArgv);
     }
@@ -210,7 +209,7 @@
         InterpreterSel == LLC_Safe) {
       SafeInterpreterSel = RunLLC;
       SafeToolArgs.push_back("--relocation-model=pic");
-      SafeInterpreter = AbstractInterpreter::createLLC(Path, Message,
+      SafeInterpreter = AbstractInterpreter::createLLC(Path.c_str(), Message,
                                                        &SafeToolArgs,
                                                        &GCCToolArgv);
     }
@@ -221,7 +220,7 @@
     if (!SafeInterpreter &&
         InterpreterSel != RunCBE) {
       SafeInterpreterSel = RunCBE;
-      SafeInterpreter = AbstractInterpreter::createCBE(Path, Message,
+      SafeInterpreter = AbstractInterpreter::createCBE(Path.c_str(), Message,
                                                        &SafeToolArgs,
                                                        &GCCToolArgv);
     }
@@ -230,7 +229,7 @@
         InterpreterSel != RunJIT) {
       SafeInterpreterSel = RunLLC;
       SafeToolArgs.push_back("--relocation-model=pic");
-      SafeInterpreter = AbstractInterpreter::createLLC(Path, Message,
+      SafeInterpreter = AbstractInterpreter::createLLC(Path.c_str(), Message,
                                                        &SafeToolArgs,
                                                        &GCCToolArgv);
     }
@@ -241,17 +240,17 @@
     break;
   case RunLLC:
     SafeToolArgs.push_back("--relocation-model=pic");
-    SafeInterpreter = AbstractInterpreter::createLLC(Path, Message,
+    SafeInterpreter = AbstractInterpreter::createLLC(Path.c_str(), Message,
                                                      &SafeToolArgs,
                                                      &GCCToolArgv);
     break;
   case RunCBE:
-    SafeInterpreter = AbstractInterpreter::createCBE(Path, Message,
+    SafeInterpreter = AbstractInterpreter::createCBE(Path.c_str(), Message,
                                                      &SafeToolArgs,
                                                      &GCCToolArgv);
     break;
   case Custom:
-    SafeInterpreter = AbstractInterpreter::createCustom(Path, Message,
+    SafeInterpreter = AbstractInterpreter::createCustom(Message,
                                                         CustomExecCommand);
     break;
   default:
@@ -261,7 +260,7 @@
   }
   if (!SafeInterpreter) { outs() << Message << "\nExiting.\n"; exit(1); }
   
-  gcc = GCC::create(getToolName(), Message, &GCCToolArgv);
+  gcc = GCC::create(Message, &GCCToolArgv);
   if (!gcc) { outs() << Message << "\nExiting.\n"; exit(1); }
 
   // If there was an error creating the selected interpreter, quit with error.
diff --git a/tools/bugpoint/OptimizerDriver.cpp b/tools/bugpoint/OptimizerDriver.cpp
index da679cf..b38d8cf 100644
--- a/tools/bugpoint/OptimizerDriver.cpp
+++ b/tools/bugpoint/OptimizerDriver.cpp
@@ -167,7 +167,7 @@
     args[n++] = "-q";
     args[n++] = tool.c_str();
   } else
-    args[n++] = ToolName.c_str();
+    args[n++] = ToolName;
 
   args[n++] = "-as-child";
   args[n++] = "-child-output";
diff --git a/tools/bugpoint/ToolRunner.cpp b/tools/bugpoint/ToolRunner.cpp
index 9180c53..bce4d52 100644
--- a/tools/bugpoint/ToolRunner.cpp
+++ b/tools/bugpoint/ToolRunner.cpp
@@ -228,10 +228,12 @@
 }
 
 // LLI create method - Try to find the LLI executable
-AbstractInterpreter *AbstractInterpreter::createLLI(const std::string &ProgPath,
+AbstractInterpreter *AbstractInterpreter::createLLI(const char *Argv0,
                                                     std::string &Message,
                                      const std::vector<std::string> *ToolArgs) {
-  std::string LLIPath = FindExecutable("lli", ProgPath).toString();
+  std::string LLIPath =
+    FindExecutable("lli", Argv0,
+                   reinterpret_cast<void *>(&createLLI)).toString();
   if (!LLIPath.empty()) {
     Message = "Found lli: " + LLIPath + "\n";
     return new LLI(LLIPath, ToolArgs);
@@ -298,7 +300,6 @@
 // Custom execution environment create method, takes the execution command
 // as arguments
 AbstractInterpreter *AbstractInterpreter::createCustom(
-                    const std::string &ProgramPath,
                     std::string &Message,
                     const std::string &ExecCommandLine) {
 
@@ -332,7 +333,7 @@
     pos = ExecCommandLine.find_first_of(delimiters, lastPos);
   }
 
-  std::string CmdPath = FindExecutable(Command, ProgramPath).toString();
+  std::string CmdPath = sys::Program::FindProgramByName(Command).toString();
   if (CmdPath.empty()) {
     Message = 
       std::string("Cannot find '") + Command + 
@@ -414,18 +415,20 @@
 
 /// createLLC - Try to find the LLC executable
 ///
-LLC *AbstractInterpreter::createLLC(const std::string &ProgramPath,
+LLC *AbstractInterpreter::createLLC(const char *Argv0,
                                     std::string &Message,
                                     const std::vector<std::string> *Args,
                                     const std::vector<std::string> *GCCArgs) {
-  std::string LLCPath = FindExecutable("llc", ProgramPath).toString();
+  std::string LLCPath =
+    FindExecutable("llc", Argv0,
+                   reinterpret_cast<void *>(&createLLC)).toString();
   if (LLCPath.empty()) {
     Message = "Cannot find `llc' in executable directory or PATH!\n";
     return 0;
   }
 
   Message = "Found llc: " + LLCPath + "\n";
-  GCC *gcc = GCC::create(ProgramPath, Message, GCCArgs);
+  GCC *gcc = GCC::create(Message, GCCArgs);
   if (!gcc) {
     errs() << Message << "\n";
     exit(1);
@@ -501,9 +504,11 @@
 
 /// createJIT - Try to find the LLI executable
 ///
-AbstractInterpreter *AbstractInterpreter::createJIT(const std::string &ProgPath,
+AbstractInterpreter *AbstractInterpreter::createJIT(const char *Argv0,
                    std::string &Message, const std::vector<std::string> *Args) {
-  std::string LLIPath = FindExecutable("lli", ProgPath).toString();
+  std::string LLIPath =
+    FindExecutable("lli", Argv0,
+                   reinterpret_cast<void *>(&createJIT)).toString();
   if (!LLIPath.empty()) {
     Message = "Found lli: " + LLIPath + "\n";
     return new JIT(LLIPath, Args);
@@ -577,11 +582,13 @@
 
 /// createCBE - Try to find the 'llc' executable
 ///
-CBE *AbstractInterpreter::createCBE(const std::string &ProgramPath,
+CBE *AbstractInterpreter::createCBE(const char *Argv0,
                                     std::string &Message,
                                     const std::vector<std::string> *Args,
                                     const std::vector<std::string> *GCCArgs) {
-  sys::Path LLCPath = FindExecutable("llc", ProgramPath);
+  sys::Path LLCPath =
+    FindExecutable("llc", Argv0,
+                   reinterpret_cast<void *>(&createCBE));
   if (LLCPath.isEmpty()) {
     Message =
       "Cannot find `llc' in executable directory or PATH!\n";
@@ -589,7 +596,7 @@
   }
 
   Message = "Found llc: " + LLCPath.toString() + "\n";
-  GCC *gcc = GCC::create(ProgramPath, Message, GCCArgs);
+  GCC *gcc = GCC::create(Message, GCCArgs);
   if (!gcc) {
     errs() << Message << "\n";
     exit(1);
@@ -827,9 +834,9 @@
 
 /// create - Try to find the `gcc' executable
 ///
-GCC *GCC::create(const std::string &ProgramPath, std::string &Message,
+GCC *GCC::create(std::string &Message,
                  const std::vector<std::string> *Args) {
-  sys::Path GCCPath = FindExecutable("gcc", ProgramPath);
+  sys::Path GCCPath = sys::Program::FindProgramByName("gcc");
   if (GCCPath.isEmpty()) {
     Message = "Cannot find `gcc' in executable directory or PATH!\n";
     return 0;
@@ -837,7 +844,7 @@
 
   sys::Path RemoteClientPath;
   if (!RemoteClient.empty())
-    RemoteClientPath = FindExecutable(RemoteClient.c_str(), ProgramPath);
+    RemoteClientPath = sys::Program::FindProgramByName(RemoteClient);
 
   Message = "Found gcc: " + GCCPath.toString() + "\n";
   return new GCC(GCCPath, RemoteClientPath, Args);
diff --git a/tools/bugpoint/ToolRunner.h b/tools/bugpoint/ToolRunner.h
index 58daef0..0082c44 100644
--- a/tools/bugpoint/ToolRunner.h
+++ b/tools/bugpoint/ToolRunner.h
@@ -57,7 +57,7 @@
 public:
   enum FileType { AsmFile, CFile };
 
-  static GCC *create(const std::string &ProgramPath, std::string &Message,
+  static GCC *create(std::string &Message,
                      const std::vector<std::string> *Args);
 
   /// ExecuteProgram - Execute the program specified by "ProgramFile" (which is
@@ -93,23 +93,20 @@
 ///
 class AbstractInterpreter {
 public:
-  static CBE *createCBE(const std::string &ProgramPath, std::string &Message,
+  static CBE *createCBE(const char *Argv0, std::string &Message,
                         const std::vector<std::string> *Args = 0,
                         const std::vector<std::string> *GCCArgs = 0);
-  static LLC *createLLC(const std::string &ProgramPath, std::string &Message,
+  static LLC *createLLC(const char *Argv0, std::string &Message,
                         const std::vector<std::string> *Args = 0,
                         const std::vector<std::string> *GCCArgs = 0);
 
-  static AbstractInterpreter* createLLI(const std::string &ProgramPath,
-                                        std::string &Message,
+  static AbstractInterpreter* createLLI(const char *Argv0, std::string &Message,
                                         const std::vector<std::string> *Args=0);
 
-  static AbstractInterpreter* createJIT(const std::string &ProgramPath,
-                                        std::string &Message,
+  static AbstractInterpreter* createJIT(const char *Argv0, std::string &Message,
                                         const std::vector<std::string> *Args=0);
 
-  static AbstractInterpreter* createCustom(const std::string &ProgramPath,
-                                           std::string &Message,
+  static AbstractInterpreter* createCustom(std::string &Message,
                                            const std::string &ExecCommandLine);
 
 
diff --git a/tools/llvm-ld/llvm-ld.cpp b/tools/llvm-ld/llvm-ld.cpp
index cc672bc..62e5f09 100644
--- a/tools/llvm-ld/llvm-ld.cpp
+++ b/tools/llvm-ld/llvm-ld.cpp
@@ -41,6 +41,11 @@
 #include <cstring>
 using namespace llvm;
 
+// Rightly this should go in a header file but it just seems such a waste.
+namespace llvm {
+extern void Optimize(Module*);
+}
+
 // Input/Output Options
 static cl::list<std::string> InputFilenames(cl::Positional, cl::OneOrMore,
   cl::desc("<input bitcode files>"));
@@ -409,7 +414,8 @@
   // support windows systems, we copy the llvm-stub.exe executable from the
   // build tree to the destination file.
   std::string ErrMsg;  
-  sys::Path llvmstub = FindExecutable("llvm-stub.exe", argv[0]);
+  sys::Path llvmstub = FindExecutable("llvm-stub.exe", argv[0],
+                                      reinterpret_cast<void *>(&Optimize));
   if (llvmstub.isEmpty())
     PrintAndExit("Could not find llvm-stub.exe executable!");
 
@@ -500,11 +506,6 @@
   }
 }
 
-// Rightly this should go in a header file but it just seems such a waste.
-namespace llvm {
-extern void Optimize(Module*);
-}
-
 int main(int argc, char **argv, char **envp) {
   // Print a stack trace if we signal out.
   sys::PrintStackTraceOnErrorSignal();
@@ -640,11 +641,12 @@
         sys::RemoveFileOnSignal(sys::Path(OutputFilename));
 
         // Determine the locations of the llc and gcc programs.
-        sys::Path llc = FindExecutable("llc", argv[0]);
+        sys::Path llc = FindExecutable("llc", argv[0],
+                                       reinterpret_cast<void *>(&Optimize));
         if (llc.isEmpty())
           PrintAndExit("Failed to find llc");
 
-        sys::Path gcc = FindExecutable("gcc", argv[0]);
+        sys::Path gcc = sys::Program::FindProgramByName("gcc");
         if (gcc.isEmpty())
           PrintAndExit("Failed to find gcc");
 
@@ -669,11 +671,12 @@
         sys::RemoveFileOnSignal(sys::Path(OutputFilename));
 
         // Determine the locations of the llc and gcc programs.
-        sys::Path llc = FindExecutable("llc", argv[0]);
+        sys::Path llc = FindExecutable("llc", argv[0],
+                                       reinterpret_cast<void *>(&Optimize));
         if (llc.isEmpty())
           PrintAndExit("Failed to find llc");
 
-        sys::Path gcc = FindExecutable("gcc", argv[0]);
+        sys::Path gcc = sys::Program::FindProgramByName("gcc");
         if (gcc.isEmpty())
           PrintAndExit("Failed to find gcc");