[llvm-commits] CVS: llvm/lib/CodeGen/BranchFolding.cpp

[Chris Lattner]

Changes in directory llvm/lib/CodeGen:

BranchFolding.cpp updated: 1.45 -> 1.46
---
Log message:

Fix PR1228: http://llvm.org/PR1228  and CodeGen/Generic/2007-04-30-LandingPadBranchFolding.ll


---
Diffs of the changes:  (+8 -2)

 BranchFolding.cpp |   10 ++++++++--
 1 files changed, 8 insertions(+), 2 deletions(-)


Index: llvm/lib/CodeGen/BranchFolding.cpp
diff -u llvm/lib/CodeGen/BranchFolding.cpp:1.45 llvm/lib/CodeGen/BranchFolding.cpp:1.46
--- llvm/lib/CodeGen/BranchFolding.cpp:1.45	Tue Mar 20 16:35:06 2007
+++ llvm/lib/CodeGen/BranchFolding.cpp	Mon Apr 30 18:35:00 2007
@@ -877,7 +877,7 @@
     // Now we know that there was no fall-through into this block, check to
     // see if it has a fall-through into its successor.
     bool CurFallsThru = CanFallThrough(MBB, CurUnAnalyzable, CurTBB, CurFBB, 
-                                            CurCond);
+                                       CurCond);
 
     if (!MBB->isLandingPad()) {
       // Check all the predecessors of this block.  If one of them has no fall
@@ -914,7 +914,13 @@
         MachineBasicBlock *SuccBB = *SI;
         MachineFunction::iterator SuccPrev = SuccBB; --SuccPrev;
         std::vector<MachineOperand> SuccPrevCond;
-        if (SuccBB != MBB && !CanFallThrough(SuccPrev)) {
+        
+        // If this block doesn't already fall-through to that successor, and if
+        // the succ doesn't already have a block that can fall through into it,
+        // and if the successor isn't an EH destination, we can arrange for the
+        // fallthrough to happen.
+        if (SuccBB != MBB && !CanFallThrough(SuccPrev) &&
+            !SuccBB->isLandingPad()) {
           MBB->moveBefore(SuccBB);
           MadeChange = true;
           return OptimizeBlock(MBB);