From: Owen Anderson <resistor@mac.com>
Date: Fri, 1 Oct 2010 20:02:55 +0000 (+0000)
Subject: Now that the profitable bits of EnableFullLoadPRE have been enabled by default, rip... 
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=7267e14327b269bd15dd9cc8083f68bef577b585;p=oota-llvm.git

Now that the profitable bits of EnableFullLoadPRE have been enabled by default, rip out the remainder.
Anyone interested in more general PRE would be better served by implementing it separately, to get real
anticipation calculation, etc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115337 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/Scalar/GVN.cpp b/lib/Transforms/Scalar/GVN.cpp
index f1272d4956d..dc75342b405 100644
--- a/lib/Transforms/Scalar/GVN.cpp
+++ b/lib/Transforms/Scalar/GVN.cpp
@@ -61,7 +61,6 @@ STATISTIC(NumPRELoad,   "Number of loads PRE'd");
 static cl::opt<bool> EnablePRE("enable-pre",
                                cl::init(true), cl::Hidden);
 static cl::opt<bool> EnableLoadPRE("enable-load-pre", cl::init(true));
-static cl::opt<bool> EnableFullLoadPRE("enable-full-load-pre", cl::init(false));
 
 //===----------------------------------------------------------------------===//
 //                         ValueTable Class
@@ -1604,14 +1603,13 @@ bool GVN::processNonLocalLoad(LoadInst *LI,
   unsigned NumUnavailablePreds = PredLoads.size();
   assert(NumUnavailablePreds != 0 &&
          "Fully available value should be eliminated above!");
-  if (!EnableFullLoadPRE) {
-    // If this load is unavailable in multiple predecessors, reject it.
-    // FIXME: If we could restructure the CFG, we could make a common pred with
-    // all the preds that don't have an available LI and insert a new load into
-    // that one block.
-    if (NumUnavailablePreds != 1)
+  
+  // If this load is unavailable in multiple predecessors, reject it.
+  // FIXME: If we could restructure the CFG, we could make a common pred with
+  // all the preds that don't have an available LI and insert a new load into
+  // that one block.
+  if (NumUnavailablePreds != 1)
       return false;
-  }
 
   // Check if the load can safely be moved to all the unavailable predecessors.
   bool CanDoPRE = true;
diff --git a/test/Transforms/GVN/2010-03-31-RedundantPHIs.ll b/test/Transforms/GVN/2010-03-31-RedundantPHIs.ll
index 066e3038b08..504004763d0 100644
--- a/test/Transforms/GVN/2010-03-31-RedundantPHIs.ll
+++ b/test/Transforms/GVN/2010-03-31-RedundantPHIs.ll
@@ -1,4 +1,4 @@
-; RUN: opt < %s -gvn -enable-full-load-pre -S | FileCheck %s
+; RUN: opt < %s -gvn -S | FileCheck %s
 
 define i8* @cat(i8* %s1, ...) nounwind {
 entry: