Fix it so llvm-objdump -arch does accept x86 and x86-64 as valid arch names.

[oota-llvm.git] / include / llvm / Support / ErrorHandling.h

diff --git a/include/llvm/Support/ErrorHandling.h b/include/llvm/Support/ErrorHandling.h
index ffcb482f75c57719008f0a3e2d873830573744b6..95b01095c1b25c89ae98ad52a22cf60b6043e15f 100644 (file)
--- a/include/llvm/Support/ErrorHandling.h
+++ b/include/llvm/Support/ErrorHandling.h
@@ -16,6 +16,7 @@
 #define LLVM_SUPPORT_ERRORHANDLING_H
 
 #include "llvm/Support/Compiler.h"
+#include "llvm/ADT/StringRef.h"
 #include <string>
 
 namespace llvm {
@@ -52,6 +53,18 @@ namespace llvm {
   /// llvm_stop_multithreaded().
   void remove_fatal_error_handler();
 
+  /// ScopedFatalErrorHandler - This is a simple helper class which just
+  /// calls install_fatal_error_handler in its constructor and
+  /// remove_fatal_error_handler in its destructor.
+  struct ScopedFatalErrorHandler {
+    explicit ScopedFatalErrorHandler(fatal_error_handler_t handler,
+                                     void *user_data = 0) {
+      install_fatal_error_handler(handler, user_data);
+    }
+
+    ~ScopedFatalErrorHandler() { remove_fatal_error_handler(); }
+  };
+
   /// Reports a serious error, calling any installed error handler. These
   /// functions are intended to be used for error conditions which are outside
   /// the control of the compiler (I/O errors, invalid user input, etc.)
@@ -60,27 +73,32 @@ namespace llvm {
   /// standard error, followed by a newline.
   /// After the error handler is called this function will call exit(1), it 
   /// does not return.
-  NORETURN void report_fatal_error(const char *reason);
-  NORETURN void report_fatal_error(const std::string &reason);
-  NORETURN void report_fatal_error(const Twine &reason);
+  LLVM_ATTRIBUTE_NORETURN void report_fatal_error(const char *reason);
+  LLVM_ATTRIBUTE_NORETURN void report_fatal_error(const std::string &reason);
+  LLVM_ATTRIBUTE_NORETURN void report_fatal_error(StringRef reason);
+  LLVM_ATTRIBUTE_NORETURN void report_fatal_error(const Twine &reason);
 
   /// This function calls abort(), and prints the optional message to stderr.
   /// Use the llvm_unreachable macro (that adds location info), instead of
   /// calling this function directly.
-  NORETURN void llvm_unreachable_internal(const char *msg=0,
-                                          const char *file=0, unsigned line=0);
+  LLVM_ATTRIBUTE_NORETURN void llvm_unreachable_internal(const char *msg=0,
+                                                         const char *file=0,
+                                                         unsigned line=0);
 }
 
-/// Prints the message and location info to stderr in !NDEBUG builds.
-/// This is intended to be used for "impossible" situations that imply
-/// a bug in the compiler.
+/// Marks that the current location is not supposed to be reachable.
+/// In !NDEBUG builds, prints the message and location info to stderr.
+/// In NDEBUG builds, becomes an optimizer hint that the current location
+/// is not supposed to be reachable.  On compilers that don't support
+/// such hints, prints a reduced message instead.
 ///
-/// In NDEBUG mode it only prints "UNREACHABLE executed".
-/// Use this instead of assert(0), so that the compiler knows this path
-/// is not reachable even for NDEBUG builds.
+/// Use this instead of assert(0).  It conveys intent more clearly and
+/// allows compilers to omit some unnecessary code.
 #ifndef NDEBUG
 #define llvm_unreachable(msg) \
   ::llvm::llvm_unreachable_internal(msg, __FILE__, __LINE__)
+#elif defined(LLVM_BUILTIN_UNREACHABLE)
+#define llvm_unreachable(msg) LLVM_BUILTIN_UNREACHABLE
 #else
 #define llvm_unreachable(msg) ::llvm::llvm_unreachable_internal()
 #endif