[llvm-commits] CVS: llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp

[Chris Lattner]

Changes in directory llvm/lib/Transforms/Scalar:

TailRecursionElimination.cpp updated: 1.23 -> 1.24
---
Log message:

Add a workaround for PR962: http://llvm.org/PR962 , disabling the more aggressive form of this
transformation.  This speeds up a C++ app 2.25x.


---
Diffs of the changes:  (+8 -0)

 TailRecursionElimination.cpp |    8 ++++++++
 1 files changed, 8 insertions(+)


Index: llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp
diff -u llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp:1.23 llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp:1.24
--- llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp:1.23	Sun Aug 27 17:42:52 2006
+++ llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp	Sun Oct 22 13:42:26 2006
@@ -140,6 +140,14 @@
     FunctionContainsEscapingAllocas |=
       CheckForEscapingAllocas(BB, CannotTCETailMarkedCall);
   }
+  
+  /// FIXME: The code generator produces really bad code when an 'escaping
+  /// alloca' is changed from being a static alloca to being a dynamic alloca.
+  /// Until this is resolved, disable this transformation if that would ever
+  /// happen.  This bug is PR962.
+  if (FunctionContainsEscapingAllocas)
+    return false;
+  
 
   // Second pass, change any tail calls to loops.
   for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB)