From: Bill Wendling <isanbard@gmail.com>
Date: Fri, 26 Aug 2011 21:18:55 +0000 (+0000)
Subject: Split the landing pad block only if it's a critical edge. Also intelligently
X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=commitdiff_plain;h=51fb91c04c920703fbd4a67ac3f85c0971b2c5a5

Split the landing pad block only if it's a critical edge. Also intelligently
split it in the other place where we're splitting critical edges.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138658 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/SjLjEHPrepare.cpp b/lib/CodeGen/SjLjEHPrepare.cpp
index ebed3d2b882..e18cbeaeb36 100644
--- a/lib/CodeGen/SjLjEHPrepare.cpp
+++ b/lib/CodeGen/SjLjEHPrepare.cpp
@@ -143,7 +143,19 @@ void SjLjEHPass::markInvokeCallSite(InvokeInst *II, int InvokeNo,
 
   // If the unwind edge has phi nodes, split the edge.
   if (isa<PHINode>(II->getUnwindDest()->begin())) {
-    SplitCriticalEdge(II, 1, this);
+    // FIXME: New EH - This if-condition will be always true in the new scheme.
+    if (II->getUnwindDest()->isLandingPad()) {
+      if (isCriticalEdge(II, 1)) {
+        SmallVector<BasicBlock*, 2> NewBBs;
+        SplitLandingPadPredecessors(II->getUnwindDest(), II->getParent(),
+                                    ".1", ".2", this, NewBBs);
+        LPadSuccMap[II] = *succ_begin(NewBBs[0]);
+      } else {
+        LPadSuccMap[II] = II->getUnwindDest();
+      }
+    } else {
+      SplitCriticalEdge(II, 1, this);
+    }
 
     // If there are any phi nodes left, they must have a single predecessor.
     while (PHINode *PN = dyn_cast<PHINode>(II->getUnwindDest()->begin())) {
@@ -194,10 +206,14 @@ splitLiveRangesAcrossInvokes(SmallVector<InvokeInst*,16> &Invokes) {
 
     // FIXME: New EH - This if-condition will be always true in the new scheme.
     if (II->getUnwindDest()->isLandingPad()) {
-      SmallVector<BasicBlock*, 2> NewBBs;
-      SplitLandingPadPredecessors(II->getUnwindDest(), II->getParent(),
-                                  ".1", ".2", this, NewBBs);
-      LPadSuccMap[II] = *succ_begin(NewBBs[0]);
+      if (isCriticalEdge(II, 1)) {
+        SmallVector<BasicBlock*, 2> NewBBs;
+        SplitLandingPadPredecessors(II->getUnwindDest(), II->getParent(),
+                                    ".1", ".2", this, NewBBs);
+        LPadSuccMap[II] = *succ_begin(NewBBs[0]);
+      } else {
+        LPadSuccMap[II] = II->getUnwindDest();
+      }
     } else {
       SplitCriticalEdge(II, 1, this);
     }