Make SimplifyCFG simply depend upon TargetTransformInfo and pass it

through as a reference rather than a pointer. There is always *some*
implementation of this available, so this simplifies code by not having
to test for whether it is available or not.

Further, it turns out there were piles of places where SimplifyCFG was
recursing and not passing down either TD or TTI. These are fixed to be
more pedantically consistent even though I don't have any particular
cases where it would matter.

llvm-svn: 171691

1 files changed, 15 insertions, 9 deletions

diff --git a/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp b/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
index 3e292e7..c243d34 100644
--- a/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
+++ b/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
@@ -48,12 +48,19 @@ namespace {
     }
 
     virtual bool runOnFunction(Function &F);
+
+    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+      AU.addRequired<TargetTransformInfo>();
+    }
   };
 }
 
 char CFGSimplifyPass::ID = 0;
-INITIALIZE_PASS(CFGSimplifyPass, "simplifycfg",
-                "Simplify the CFG", false, false)
+INITIALIZE_PASS_BEGIN(CFGSimplifyPass, "simplifycfg", "Simplify the CFG",
+                      false, false)
+INITIALIZE_AG_DEPENDENCY(TargetTransformInfo)
+INITIALIZE_PASS_END(CFGSimplifyPass, "simplifycfg", "Simplify the CFG",
+                    false, false)
 
 // Public interface to the CFGSimplification pass
 FunctionPass *llvm::createCFGSimplificationPass() {
@@ -293,8 +300,8 @@ static bool mergeEmptyReturnBlocks(Function &F) {
 
 /// iterativelySimplifyCFG - Call SimplifyCFG on all the blocks in the function,
 /// iterating until no more changes are made.
-static bool iterativelySimplifyCFG(Function &F, const DataLayout *TD,
-                                   const TargetTransformInfo *TTI) {
+static bool iterativelySimplifyCFG(Function &F, const TargetTransformInfo &TTI,
+                                   const DataLayout *TD) {
   bool Changed = false;
   bool LocalChange = true;
   while (LocalChange) {
@@ -303,7 +310,7 @@ static bool iterativelySimplifyCFG(Function &F, const DataLayout *TD,
     // Loop over all of the basic blocks and remove them if they are unneeded...
     //
     for (Function::iterator BBIt = F.begin(); BBIt != F.end(); ) {
-      if (SimplifyCFG(BBIt++, TD, TTI)) {
+      if (SimplifyCFG(BBIt++, TTI, TD)) {
         LocalChange = true;
         ++NumSimpl;
       }
@@ -317,12 +324,11 @@ static bool iterativelySimplifyCFG(Function &F, const DataLayout *TD,
 // simplify the CFG.
 //
 bool CFGSimplifyPass::runOnFunction(Function &F) {
+  const TargetTransformInfo &TTI = getAnalysis<TargetTransformInfo>();
   const DataLayout *TD = getAnalysisIfAvailable<DataLayout>();
-  const TargetTransformInfo *TTI =
-      getAnalysisIfAvailable<TargetTransformInfo>();
   bool EverChanged = removeUnreachableBlocksFromFn(F);
   EverChanged |= mergeEmptyReturnBlocks(F);
-  EverChanged |= iterativelySimplifyCFG(F, TD, TTI);
+  EverChanged |= iterativelySimplifyCFG(F, TTI, TD);
 
   // If neither pass changed anything, we're done.
   if (!EverChanged) return false;
@@ -336,7 +342,7 @@ bool CFGSimplifyPass::runOnFunction(Function &F) {
     return true;
 
   do {
-    EverChanged = iterativelySimplifyCFG(F, TD, TTI);
+    EverChanged = iterativelySimplifyCFG(F, TTI, TD);
     EverChanged |= removeUnreachableBlocksFromFn(F);
   } while (EverChanged);