From a5422e404885650e51fd14f55d5e9636bfcd47f4 Mon Sep 17 00:00:00 2001
From: Chris Lattner
Date: Mon, 8 Mar 2004 22:29:35 +0000
Subject: [PATCH] Update the profiling section
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12243 91177308-0d34-0410-b5e6-96231b3b80d8
---
docs/OpenProjects.html | 27 ++++++++++++++++++++++-----
1 file changed, 22 insertions(+), 5 deletions(-)
diff --git a/docs/OpenProjects.html b/docs/OpenProjects.html
index 1a70dc84050..d528bf3e76e 100644
--- a/docs/OpenProjects.html
+++ b/docs/OpenProjects.html
@@ -229,11 +229,11 @@ themselves. It seems natural to want to take advantage of this...
-
We are getting to the point where we really need a unified infrastructure for
-profile guided optimizations. It would be wonderful to be able to write profile
-guided transformations which can be performed either at static compile time
-(compile time or offline optimization time) or at runtime in a JIT type setup.
-The LLVM transformation itself shouldn't need to know how it is being used.
+
We now have a unified infrastructure for writing profile-guided
+transformations, which will work either at offline-compile-time or in the JIT,
+but we don't have many transformations. We would welcome new profile-guided
+transformations as well as improvements to the current profiling system.
+
Ideas for profile guided transformations:
@@ -245,6 +245,23 @@ The LLVM transformation itself shouldn't need to know how it is being used.
...
+
Improvements to the existing support:
+
+
+- The current block and edge profiling code that gets inserted is very simple
+and inefficient. Through the use of control-dependence information, many fewer
+counters could be inserted into the code. Also, if the execution count of a
+loop is known to be a compile-time or runtime constant, all of the counters in
+the loop could be avoided.
+
+- You could implement one of the "static profiling" algorithms which analyze a
+piece of code an make educated guesses about the relative execution frequencies
+of various parts of the code.
+
+- You could add path profiling support, or adapt the existing LLVM path
+profiling code to work with the generic profiling interfaces.
+
+
--
2.34.1