Add an unwind_to field to basic blocks, making them Users instead of Values.

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

diff --git a/include/llvm/Support/SlowOperationInformer.h b/include/llvm/Support/SlowOperationInformer.h
index f27a05571b4aafc5fff49e37b4c086696cc99a01..b30aa987523cf97504c2539334ce2f689a38c51d 100644 (file)
--- a/include/llvm/Support/SlowOperationInformer.h
+++ b/include/llvm/Support/SlowOperationInformer.h
@@ -1,55 +1,64 @@
-//===- SlowOperationInformer.h - Keep the user informed ---------*- C++ -*-===//
-// 
+//===- llvm/Support/SlowOperationInformer.h - Keep user informed *- C++ -*-===//
+//
 //                     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 file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
 //===----------------------------------------------------------------------===//
 //
 // This file defines a simple object which can be used to let the user know what
-// is going on when a slow operation is happening,l and gives them the ability
-// to cancel it.  Potentially slow operations can stack allocate one of these
+// is going on when a slow operation is happening, and gives them the ability to
+// cancel it.  Potentially slow operations can stack allocate one of these
 // objects, and periodically call the "progress" method to update the progress
-// bar.  If the operation takes more than 3 seconds to complete, the progress
-// bar is automatically shown and updated every second.  As such, the slow
-// operation should not print stuff to the screen, and should not be confused if
-// an extra line appears on the screen (ie, the cursor should be at the start of
-// the line).
+// bar.  If the operation takes more than 1 second to complete, the progress bar
+// is automatically shown and updated.  As such, the slow operation should not
+// print stuff to the screen, and should not be confused if an extra line
+// appears on the screen (ie, the cursor should be at the start of the line).
 //
 // If the user presses CTRL-C during the operation, the next invocation of the
-// progress method with throw an std::string object indicating that the
-// operation was cancelled.  As such, client code must be exception safe around
-// the progress method.
+// progress method return true indicating that the operation was cancelled.
 //
 // Because SlowOperationInformers fiddle around with signals, they cannot be
-// nested.  The SIGINT signal handler is restored after the
-// SlowOperationInformer is destroyed, but the SIGALRM handlers is set back to
-// the default.
+// nested, and interact poorly with threads.  The SIGALRM handler is set back to
+// SIGDFL, but the SIGINT signal handler is restored when the
+// SlowOperationInformer is destroyed.
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef SUPPORT_SLOW_OPERATION_INFORMER_H
-#define SUPPORT_SLOW_OPERATION_INFORMER_H
+#ifndef LLVM_SUPPORT_SLOW_OPERATION_INFORMER_H
+#define LLVM_SUPPORT_SLOW_OPERATION_INFORMER_H
 
 #include <string>
+#include <cassert>
+#include "llvm/Support/DataTypes.h"
 
 namespace llvm {
   class SlowOperationInformer {
     std::string OperationName;
     unsigned LastPrintAmount;
-    
+
     SlowOperationInformer(const SlowOperationInformer&);   // DO NOT IMPLEMENT
     void operator=(const SlowOperationInformer&);          // DO NOT IMPLEMENT
   public:
     SlowOperationInformer(const std::string &Name);
     ~SlowOperationInformer();
-    
-    /// progress - Clients should periodically call this method when they are in
-    /// an exception-safe state.  The Amount variable should indicate how far
+
+    /// progress - Clients should periodically call this method when they can
+    /// handle cancellation.  The Amount variable should indicate how far
     /// along the operation is, given in 1/10ths of a percent (in other words,
-    /// Amount should range from 0 to 1000).
-    void progress(unsigned Amount);
+    /// Amount should range from 0 to 1000).  If the user cancels the operation,
+    /// this returns true, false otherwise.
+    bool progress(unsigned Amount);
+
+    /// progress - Same as the method above, but this performs the division for
+    /// you, and helps you avoid overflow if you are dealing with largish
+    /// numbers.
+    bool progress(unsigned Current, unsigned Maximum) {
+      assert(Maximum != 0 &&
+             "Shouldn't be doing work if there is nothing to do!");
+      return progress(Current*uint64_t(1000UL)/Maximum);
+    }
   };
 } // end namespace llvm