Added DEBUG message to ObjCARC when we transform objc_initWeak(p, null) => *p = null.

[oota-llvm.git] / lib / Transforms / Scalar / TailRecursionElimination.cpp

diff --git a/lib/Transforms/Scalar/TailRecursionElimination.cpp b/lib/Transforms/Scalar/TailRecursionElimination.cpp
index 539cc6f0baf50471ef854c4c723acd0521bb25e2..6572e0915e8247a061ff531fcf4d0f3e147c0fba 100644 (file)
--- a/lib/Transforms/Scalar/TailRecursionElimination.cpp
+++ b/lib/Transforms/Scalar/TailRecursionElimination.cpp
@@ -52,24 +52,25 @@
 
 #define DEBUG_TYPE "tailcallelim"
 #include "llvm/Transforms/Scalar.h"
-#include "llvm/Transforms/Utils/BasicBlockUtils.h"
-#include "llvm/Transforms/Utils/Local.h"
-#include "llvm/Constants.h"
-#include "llvm/DerivedTypes.h"
-#include "llvm/Function.h"
-#include "llvm/Instructions.h"
-#include "llvm/IntrinsicInst.h"
-#include "llvm/Pass.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/CaptureTracking.h"
 #include "llvm/Analysis/InlineCost.h"
 #include "llvm/Analysis/InstructionSimplify.h"
 #include "llvm/Analysis/Loads.h"
-#include "llvm/Support/CallSite.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Pass.h"
 #include "llvm/Support/CFG.h"
+#include "llvm/Support/CallSite.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/ADT/STLExtras.h"
+#include "llvm/Transforms/Utils/BasicBlockUtils.h"
+#include "llvm/Transforms/Utils/Local.h"
 using namespace llvm;
 
 STATISTIC(NumEliminated, "Number of tail calls removed");
@@ -171,7 +172,7 @@ bool TailCallElim::runOnFunction(Function &F) {
     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
@@ -209,10 +210,10 @@ bool TailCallElim::runOnFunction(Function &F) {
     }
   }
 
-  // Finally, if this function contains no non-escaping allocas, mark all calls
-  // in the function as eligible for tail calls (there is no stack memory for
-  // them to access).
-  if (!FunctionContainsEscapingAllocas)
+  // Finally, if this function contains no non-escaping allocas, or calls
+  // setjmp, mark all calls in the function as eligible for tail calls
+  //(there is no stack memory for them to access).
+  if (!FunctionContainsEscapingAllocas && !F.callsFunctionThatReturnsTwice())
     for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
       for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
         if (CallInst *CI = dyn_cast<CallInst>(I)) {
@@ -233,7 +234,7 @@ bool TailCallElim::CanMoveAboveCall(Instruction *I, CallInst *CI) {
   // call does not mod/ref the memory location being processed.
   if (I->mayHaveSideEffects())  // This also handles volatile loads.
     return false;
-  
+
   if (LoadInst *L = dyn_cast<LoadInst>(I)) {
     // Loads may always be moved above calls without side effects.
     if (CI->mayHaveSideEffects()) {
@@ -363,7 +364,7 @@ TailCallElim::FindTRECandidate(Instruction *TI,
 
   if (&BB->front() == TI) // Make sure there is something before the terminator.
     return 0;
-  
+
   // Scan backwards from the return, checking to see if there is a tail call in
   // this block.  If so, set CI to it.
   CallInst *CI = 0;
@@ -387,10 +388,10 @@ TailCallElim::FindTRECandidate(Instruction *TI,
   //   double fabs(double f) { return __builtin_fabs(f); } // a 'fabs' call
   // and disable this xform in this case, because the code generator will
   // lower the call to fabs into inline code.
-  if (BB == &F->getEntryBlock() && 
+  if (BB == &F->getEntryBlock() &&
       FirstNonDbg(BB->front()) == CI &&
       FirstNonDbg(llvm::next(BB->begin())) == TI &&
-      callIsSmall(F)) {
+      callIsSmall(CI)) {
     // A single-block function with just a call and a return. Check that
     // the arguments match.
     CallSite::arg_iterator I = CallSite(CI).arg_begin(),
@@ -431,7 +432,7 @@ bool TailCallElim::EliminateRecursiveTailCall(CallInst *CI, ReturnInst *Ret,
   BasicBlock::iterator BBI = CI;
   for (++BBI; &*BBI != Ret; ++BBI) {
     if (CanMoveAboveCall(BBI, CI)) continue;
-    
+
     // If we can't move the instruction above the call, it might be because it
     // is an associative and commutative operation that could be transformed
     // using accumulator recursion elimination.  Check to see if this is the