[llvm] 701f723 - [VPlan] Use VPRecipeWithIRFlags for VPReplicateRecipe, retire poison map

[Florian Hahn via llvm-commits]

Author: Florian Hahn
Date: 2023-05-15T11:49:20+01:00
New Revision: 701f7230cdc065e180077b66ba3c839adb9092b4

URL: https://github.com/llvm/llvm-project/commit/701f7230cdc065e180077b66ba3c839adb9092b4
DIFF: https://github.com/llvm/llvm-project/commit/701f7230cdc065e180077b66ba3c839adb9092b4.diff

LOG: [VPlan] Use VPRecipeWithIRFlags for VPReplicateRecipe, retire poison map

Update VPReplicateRecipe to use VPRecipeWithIRFlags for IR flag
handling. Retire separate MayGeneratePoisonRecipes map.

Depends on D149082.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D150027

Added: 
    

Modified: 
    llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
    llvm/lib/Transforms/Vectorize/VPlan.h
    llvm/unittests/Transforms/Vectorize/VPlanTest.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index 0ca5649c8e49c..aaa6a3bef7c8e 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -1083,15 +1083,15 @@ void InnerLoopVectorizer::collectPoisonGeneratingRecipes(
 
       // This recipe contributes to the address computation of a widen
       // load/store. If the underlying instruction has poison-generating flags,
-      // either drop them directly if the recipe already models the flags or
-      // collect them in a set.
-      // TODO: Migrate all relevant recipes to hold their own flags.
-      Instruction *Instr = CurRec->getUnderlyingInstr();
-      if (Instr && Instr->hasPoisonGeneratingFlags()) {
-        if (auto *RecWithFlags = dyn_cast<VPRecipeWithIRFlags>(CurRec))
-          RecWithFlags->dropPoisonGeneratingFlags();
-        else
-          State.MayGeneratePoisonRecipes.insert(CurRec);
+      // drop them directly.
+      if (auto *RecWithFlags = dyn_cast<VPRecipeWithIRFlags>(CurRec)) {
+        RecWithFlags->dropPoisonGeneratingFlags();
+      } else {
+        Instruction *Instr = CurRec->getUnderlyingInstr();
+        (void)Instr;
+        assert((!Instr || !Instr->hasPoisonGeneratingFlags()) &&
+               "found instruction with poison generating flags not covered by "
+               "VPRecipeWithIRFlags");
       }
 
       // Add new definitions to the worklist.
@@ -2799,14 +2799,7 @@ void InnerLoopVectorizer::scalarizeInstruction(const Instruction *Instr,
   if (!IsVoidRetTy)
     Cloned->setName(Instr->getName() + ".cloned");
 
-  // If the scalarized instruction contributes to the address computation of a
-  // widen masked load/store which was in a basic block that needed predication
-  // and is not predicated after vectorization, we can't propagate
-  // poison-generating flags (nuw/nsw, exact, inbounds, etc.). The scalarized
-  // instruction could feed a poison value to the base address of the widen
-  // load/store.
-  if (State.MayGeneratePoisonRecipes.contains(RepRecipe))
-    Cloned->dropPoisonGeneratingFlags();
+  RepRecipe->setFlags(Cloned);
 
   if (Instr->getDebugLoc())
     State.setDebugLocFromInst(Instr);

diff  --git a/llvm/lib/Transforms/Vectorize/VPlan.h b/llvm/lib/Transforms/Vectorize/VPlan.h
index 38dc08b7c6a20..45a375275e80b 100644
--- a/llvm/lib/Transforms/Vectorize/VPlan.h
+++ b/llvm/lib/Transforms/Vectorize/VPlan.h
@@ -398,10 +398,6 @@ struct VPTransformState {
   /// Pointer to the VPlan code is generated for.
   VPlan *Plan;
 
-  /// Holds recipes that may generate a poison value that is used after
-  /// vectorization, even when their operands are not poison.
-  SmallPtrSet<VPRecipeBase *, 16> MayGeneratePoisonRecipes;
-
   /// The loop object for the current parent region, or nullptr.
   Loop *CurrentVectorLoop = nullptr;
 
@@ -1017,7 +1013,8 @@ class VPRecipeWithIRFlags : public VPRecipeBase {
 
   static inline bool classof(const VPRecipeBase *R) {
     return R->getVPDefID() == VPRecipeBase::VPWidenSC ||
-           R->getVPDefID() == VPRecipeBase::VPWidenGEPSC;
+           R->getVPDefID() == VPRecipeBase::VPWidenGEPSC ||
+           R->getVPDefID() == VPRecipeBase::VPReplicateSC;
   }
 
   /// Drop all poison-generating flags.
@@ -1723,7 +1720,7 @@ class VPReductionRecipe : public VPRecipeBase, public VPValue {
 /// copies of the original scalar type, one per lane, instead of producing a
 /// single copy of widened type for all lanes. If the instruction is known to be
 /// uniform only one copy, per lane zero, will be generated.
-class VPReplicateRecipe : public VPRecipeBase, public VPValue {
+class VPReplicateRecipe : public VPRecipeWithIRFlags, public VPValue {
   /// Indicator if only a single replica per lane is needed.
   bool IsUniform;
 
@@ -1734,8 +1731,8 @@ class VPReplicateRecipe : public VPRecipeBase, public VPValue {
   template <typename IterT>
   VPReplicateRecipe(Instruction *I, iterator_range<IterT> Operands,
                     bool IsUniform, VPValue *Mask = nullptr)
-      : VPRecipeBase(VPDef::VPReplicateSC, Operands), VPValue(this, I),
-        IsUniform(IsUniform), IsPredicated(Mask) {
+      : VPRecipeWithIRFlags(VPDef::VPReplicateSC, Operands, *I),
+        VPValue(this, I), IsUniform(IsUniform), IsPredicated(Mask) {
     if (Mask)
       addOperand(Mask);
   }

diff  --git a/llvm/unittests/Transforms/Vectorize/VPlanTest.cpp b/llvm/unittests/Transforms/Vectorize/VPlanTest.cpp
index e0c4ad6b42c7f..2d0a584c8bdd2 100644
--- a/llvm/unittests/Transforms/Vectorize/VPlanTest.cpp
+++ b/llvm/unittests/Transforms/Vectorize/VPlanTest.cpp
@@ -1006,10 +1006,14 @@ TEST(VPRecipeTest, CastVPReplicateRecipeToVPUser) {
   Args.push_back(&Op1);
   Args.push_back(&Op2);
 
-  VPReplicateRecipe Recipe(nullptr, make_range(Args.begin(), Args.end()), true);
+  IntegerType *Int32 = IntegerType::get(C, 32);
+  FunctionType *FTy = FunctionType::get(Int32, false);
+  auto *Call = CallInst::Create(FTy, UndefValue::get(FTy));
+  VPReplicateRecipe Recipe(Call, make_range(Args.begin(), Args.end()), true);
   EXPECT_TRUE(isa<VPUser>(&Recipe));
   VPRecipeBase *BaseR = &Recipe;
   EXPECT_TRUE(isa<VPUser>(BaseR));
+  delete Call;
 }
 
 TEST(VPRecipeTest, CastVPBranchOnMaskRecipeToVPUser) {