reland [InstCombine] convert assumes to operand bundles

Instcombine will convert the nonnull and alignment assumption that use the boolean condtion
to an assumption that uses the operand bundles when knowledge retention is enabled.

Differential Revision: https://reviews.llvm.org/D82703

1 files changed, 39 insertions, 15 deletions

diff --git a/llvm/lib/Transforms/Utils/AssumeBundleBuilder.cpp b/llvm/lib/Transforms/Utils/AssumeBundleBuilder.cpp
index 3daff3b..e6e5272 100644
--- a/llvm/lib/Transforms/Utils/AssumeBundleBuilder.cpp
+++ b/llvm/lib/Transforms/Utils/AssumeBundleBuilder.cpp
@@ -6,8 +6,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#define DEBUG_TYPE "assume-builder"
-
 #include "llvm/Transforms/Utils/AssumeBundleBuilder.h"
 #include "llvm/ADT/DepthFirstIterator.h"
 #include "llvm/ADT/MapVector.h"
@@ -37,6 +35,8 @@ cl::opt<bool> EnableKnowledgeRetention(
     cl::desc(
         "enable preservation of attributes throughout code transformation"));
 
+#define DEBUG_TYPE "assume-builder"
+
 STATISTIC(NumAssumeBuilt, "Number of assume built by the assume builder");
 STATISTIC(NumBundlesInAssumes, "Total number of Bundles in the assume built");
 STATISTIC(NumAssumesMerged,
@@ -65,7 +65,7 @@ bool isUsefullToPreserve(Attribute::AttrKind Kind) {
 
 /// This function will try to transform the given knowledge into a more
 /// canonical one. the canonical knowledge maybe the given one.
-RetainedKnowledge canonicalizedKnowledge(RetainedKnowledge RK, Module *M) {
+RetainedKnowledge canonicalizedKnowledge(RetainedKnowledge RK, DataLayout DL) {
   switch (RK.AttrKind) {
   default:
     return RK;
@@ -76,8 +76,7 @@ RetainedKnowledge canonicalizedKnowledge(RetainedKnowledge RK, Module *M) {
     Value *V = RK.WasOn->stripInBoundsOffsets([&](const Value *Strip) {
       if (auto *GEP = dyn_cast<GEPOperator>(Strip))
         RK.ArgValue =
-            MinAlign(RK.ArgValue,
-                     GEP->getMaxPreservedAlignment(M->getDataLayout()).value());
+            MinAlign(RK.ArgValue, GEP->getMaxPreservedAlignment(DL).value());
     });
     RK.WasOn = V;
     return RK;
@@ -85,8 +84,8 @@ RetainedKnowledge canonicalizedKnowledge(RetainedKnowledge RK, Module *M) {
   case Attribute::Dereferenceable:
   case Attribute::DereferenceableOrNull: {
     int64_t Offset = 0;
-    Value *V = GetPointerBaseWithConstantOffset(
-        RK.WasOn, Offset, M->getDataLayout(), /*AllowNonInBounds*/ false);
+    Value *V = GetPointerBaseWithConstantOffset(RK.WasOn, Offset, DL,
+                                                /*AllowNonInBounds*/ false);
     if (Offset < 0)
       return RK;
     RK.ArgValue = RK.ArgValue + Offset;
@@ -103,16 +102,16 @@ struct AssumeBuilderState {
 
   using MapKey = std::pair<Value *, Attribute::AttrKind>;
   SmallMapVector<MapKey, unsigned, 8> AssumedKnowledgeMap;
-  Instruction *InstBeingRemoved = nullptr;
+  Instruction *InstBeingModified = nullptr;
   AssumptionCache* AC = nullptr;
   DominatorTree* DT = nullptr;
 
   AssumeBuilderState(Module *M, Instruction *I = nullptr,
                      AssumptionCache *AC = nullptr, DominatorTree *DT = nullptr)
-      : M(M), InstBeingRemoved(I), AC(AC), DT(DT) {}
+      : M(M), InstBeingModified(I), AC(AC), DT(DT) {}
 
   bool tryToPreserveWithoutAddingAssume(RetainedKnowledge RK) {
-    if (!InstBeingRemoved || !RK.WasOn)
+    if (!InstBeingModified || !RK.WasOn)
       return false;
     bool HasBeenPreserved = false;
     Use* ToUpdate = nullptr;
@@ -120,13 +119,12 @@ struct AssumeBuilderState {
         RK.WasOn, {RK.AttrKind}, AC,
         [&](RetainedKnowledge RKOther, Instruction *Assume,
             const CallInst::BundleOpInfo *Bundle) {
-          if (!isValidAssumeForContext(Assume, InstBeingRemoved, DT))
+          if (!isValidAssumeForContext(Assume, InstBeingModified, DT))
             return false;
           if (RKOther.ArgValue >= RK.ArgValue) {
             HasBeenPreserved = true;
             return true;
-          } else if (isValidAssumeForContext(InstBeingRemoved, Assume,
-                                             DT)) {
+          } else if (isValidAssumeForContext(InstBeingModified, Assume, DT)) {
             HasBeenPreserved = true;
             IntrinsicInst *Intr = cast<IntrinsicInst>(Assume);
             ToUpdate = &Intr->op_begin()[Bundle->Begin + ABA_Argument];
@@ -162,14 +160,14 @@ struct AssumeBuilderState {
         if (RK.WasOn->use_empty())
           return false;
         Use *SingleUse = RK.WasOn->getSingleUndroppableUse();
-        if (SingleUse && SingleUse->getUser() == InstBeingRemoved)
+        if (SingleUse && SingleUse->getUser() == InstBeingModified)
           return false;
       }
     return true;
   }
 
   void addKnowledge(RetainedKnowledge RK) {
-    RK = canonicalizedKnowledge(RK, M);
+    RK = canonicalizedKnowledge(RK, M->getDataLayout());
 
     if (!isKnowledgeWorthPreserving(RK))
       return;
@@ -299,6 +297,32 @@ void llvm::salvageKnowledge(Instruction *I, AssumptionCache *AC,
   }
 }
 
+IntrinsicInst *
+llvm::buildAssumeFromKnowledge(ArrayRef<RetainedKnowledge> Knowledge,
+                               Instruction *CtxI, AssumptionCache *AC,
+                               DominatorTree *DT) {
+  AssumeBuilderState Builder(CtxI->getModule(), CtxI, AC, DT);
+  for (const RetainedKnowledge &RK : Knowledge)
+    Builder.addKnowledge(RK);
+  return Builder.build();
+}
+
+RetainedKnowledge llvm::simplifyRetainedKnowledge(CallBase *Assume,
+                                                  RetainedKnowledge RK,
+                                                  AssumptionCache *AC,
+                                                  DominatorTree *DT) {
+  assert(Assume->getIntrinsicID() == Intrinsic::assume);
+  AssumeBuilderState Builder(Assume->getModule(), Assume, AC, DT);
+  RK = canonicalizedKnowledge(RK, Assume->getModule()->getDataLayout());
+
+  if (!Builder.isKnowledgeWorthPreserving(RK))
+    return RetainedKnowledge::none();
+
+  if (Builder.tryToPreserveWithoutAddingAssume(RK))
+    return RetainedKnowledge::none();
+  return RK;
+}
+
 namespace {
 
 struct AssumeSimplify {