[PM] Port memdep to the new pass manager.

This is a fairly straightforward port to the new pass manager with one
exception. It removes a very questionable use of releaseMemory() in
the old pass to invalidate its caches between runs on a function.
I don't think this is really guaranteed to be safe. I've just used the
more direct port to the new PM to address this by nuking the results
object each time the pass runs. While this could cause some minor malloc
traffic increase, I don't expect the compile time performance hit to be
noticable, and it makes the correctness and other aspects of the pass
much easier to reason about. In some cases, it may make things faster by
making the sets and maps smaller with better locality. Indeed, the
measurements collected by Bruno (thanks!!!) show mostly compile time
improvements.

There is sadly very limited testing at this point as there are only two
tests of memdep, and both rely on GVN. I'll be porting GVN next and that
will exercise this heavily though.

Differential Revision: http://reviews.llvm.org/D17962

llvm-svn: 263082

1 files changed, 2 insertions, 2 deletions

diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
index 72db980cf57..bb11a98622c 100644
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -66,7 +66,7 @@ void llvm::DeleteDeadBlock(BasicBlock *BB) {
 /// when all entries to the PHI nodes in a block are guaranteed equal, such as
 /// when the block has exactly one predecessor.
 void llvm::FoldSingleEntryPHINodes(BasicBlock *BB,
-                                   MemoryDependenceAnalysis *MemDep) {
+                                   MemoryDependenceResults *MemDep) {
   if (!isa<PHINode>(BB->begin())) return;
 
   while (PHINode *PN = dyn_cast<PHINode>(BB->begin())) {
@@ -107,7 +107,7 @@ bool llvm::DeleteDeadPHIs(BasicBlock *BB, const TargetLibraryInfo *TLI) {
 /// if possible.  The return value indicates success or failure.
 bool llvm::MergeBlockIntoPredecessor(BasicBlock *BB, DominatorTree *DT,
                                      LoopInfo *LI,
-                                     MemoryDependenceAnalysis *MemDep) {
+                                     MemoryDependenceResults *MemDep) {
   // Don't merge away blocks who have their address taken.
   if (BB->hasAddressTaken()) return false;