Remove the very substantial, largely unmaintained legacy PGO

infrastructure.

This was essentially work toward PGO based on a design that had several
flaws, partially dating from a time when LLVM had a different
architecture, and with an effort to modernize it abandoned without being
completed. Since then, it has bitrotted for several years further. The
result is nearly unusable, and isn't helping any of the modern PGO
efforts. Instead, it is getting in the way, adding confusion about PGO
in LLVM and distracting everyone with maintenance on essentially dead
code. Removing it paves the way for modern efforts around PGO.

Among other effects, this removes the last of the runtime libraries from
LLVM. Those are being developed in the separate 'compiler-rt' project
now, with somewhat different licensing specifically more approriate for
runtimes.

llvm-svn: 191835

2 files changed, 1 insertions, 14 deletions

diff --git a/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp b/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp
index 8f3ff96d7e7..0e7f7f78440 100644
--- a/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp
+++ b/llvm/lib/Transforms/Utils/BreakCriticalEdges.cpp
@@ -22,7 +22,6 @@
 #include "llvm/Analysis/CFG.h"
 #include "llvm/Analysis/Dominators.h"
 #include "llvm/Analysis/LoopInfo.h"
-#include "llvm/Analysis/ProfileInfo.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/Type.h"
@@ -45,7 +44,6 @@ namespace {
     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
       AU.addPreserved<DominatorTree>();
       AU.addPreserved<LoopInfo>();
-      AU.addPreserved<ProfileInfo>();
 
       // No loop canonicalization guarantees are broken by this pass.
       AU.addPreservedID(LoopSimplifyID);
@@ -213,10 +211,9 @@ BasicBlock *llvm::SplitCriticalEdge(TerminatorInst *TI, unsigned SuccNum,
 
   DominatorTree *DT = P->getAnalysisIfAvailable<DominatorTree>();
   LoopInfo *LI = P->getAnalysisIfAvailable<LoopInfo>();
-  ProfileInfo *PI = P->getAnalysisIfAvailable<ProfileInfo>();
 
   // If we have nothing to update, just return.
-  if (DT == 0 && LI == 0 && PI == 0)
+  if (DT == 0 && LI == 0)
     return NewBB;
 
   // Now update analysis information.  Since the only predecessor of NewBB is
@@ -369,9 +366,5 @@ BasicBlock *llvm::SplitCriticalEdge(TerminatorInst *TI, unsigned SuccNum,
     }
   }
 
-  // Update ProfileInfo if it is around.
-  if (PI)
-    PI->splitEdge(TIBB, DestBB, NewBB, MergeIdenticalEdges);
-
   return NewBB;
 }
diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index 56a2d92d47c..82b8da3a107 100644
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -20,7 +20,6 @@
 #include "llvm/Analysis/Dominators.h"
 #include "llvm/Analysis/InstructionSimplify.h"
 #include "llvm/Analysis/MemoryBuiltins.h"
-#include "llvm/Analysis/ProfileInfo.h"
 #include "llvm/Analysis/ValueTracking.h"
 #include "llvm/DIBuilder.h"
 #include "llvm/DebugInfo.h"
@@ -513,11 +512,6 @@ void llvm::MergeBasicBlockIntoOnlyPred(BasicBlock *DestBB, Pass *P) {
       DT->changeImmediateDominator(DestBB, PredBBIDom);
       DT->eraseNode(PredBB);
     }
-    ProfileInfo *PI = P->getAnalysisIfAvailable<ProfileInfo>();
-    if (PI) {
-      PI->replaceAllUses(PredBB, DestBB);
-      PI->removeEdge(ProfileInfo::getEdge(PredBB, DestBB));
-    }
   }
   // Nuke BB.
   PredBB->eraseFromParent();