[llvm] f586de8 - [VPlan] Remove PredInst2Recipe, use VP operands instead. (NFC)

[Florian Hahn via llvm-commits]

Author: Florian Hahn
Date: 2021-03-16T17:40:35Z
New Revision: f586de8459ce897faf532fdd49fd4aa81747589e

URL: https://github.com/llvm/llvm-project/commit/f586de8459ce897faf532fdd49fd4aa81747589e
DIFF: https://github.com/llvm/llvm-project/commit/f586de8459ce897faf532fdd49fd4aa81747589e.diff

LOG: [VPlan] Remove PredInst2Recipe, use VP operands instead. (NFC)

Instead of maintaining a separate map from predicated instructions to
recipes, we can instead directly look at the VP operands. If the operand
comes from a predicated instruction, the operand will be a
VPPredInstPHIRecipe with a VPReplicateRecipe as its operand.

Added: 
    

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

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index c92b00078c7e..f6f51e78bb27 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -8534,7 +8534,6 @@ VPWidenRecipe *VPRecipeBuilder::tryToWiden(Instruction *I, VPlan &Plan) const {
 
 VPBasicBlock *VPRecipeBuilder::handleReplication(
     Instruction *I, VFRange &Range, VPBasicBlock *VPBB,
-    DenseMap<Instruction *, VPReplicateRecipe *> &PredInst2Recipe,
     VPlanPtr &Plan) {
   bool IsUniform = LoopVectorizationPlanner::getDecisionAndClampRange(
       [&](ElementCount VF) { return CM.isUniformAfterVectorization(I, VF); },
@@ -8552,10 +8551,16 @@ VPBasicBlock *VPRecipeBuilder::handleReplication(
   // Find if I uses a predicated instruction. If so, it will use its scalar
   // value. Avoid hoisting the insert-element which packs the scalar value into
   // a vector value, as that happens iff all users use the vector value.
-  for (auto &Op : I->operands())
-    if (auto *PredInst = dyn_cast<Instruction>(Op))
-      if (PredInst2Recipe.find(PredInst) != PredInst2Recipe.end())
-        PredInst2Recipe[PredInst]->setAlsoPack(false);
+  for (VPValue *Op : Recipe->operands()) {
+    auto *PredR = dyn_cast_or_null<VPPredInstPHIRecipe>(Op->getDef());
+    if (!PredR)
+      continue;
+    auto *RepR =
+        cast_or_null<VPReplicateRecipe>(PredR->getOperand(0)->getDef());
+    assert(RepR->isPredicated() &&
+           "expected Replicate recipe to be predicated");
+    RepR->setAlsoPack(false);
+  }
 
   // Finalize the recipe for Instr, first if it is not predicated.
   if (!IsPredicated) {
@@ -8567,7 +8572,6 @@ VPBasicBlock *VPRecipeBuilder::handleReplication(
   assert(VPBB->getSuccessors().empty() &&
          "VPBB has successors when handling predicated replication.");
   // Record predicated instructions for above packing optimizations.
-  PredInst2Recipe[I] = Recipe;
   VPBlockBase *Region = createReplicateRegion(I, Recipe, Plan);
   VPBlockUtils::insertBlockAfter(Region, VPBB);
   auto *RegSucc = new VPBasicBlock();
@@ -8695,11 +8699,6 @@ VPlanPtr LoopVectorizationPlanner::buildVPlanWithVPRecipes(
     VFRange &Range, SmallPtrSetImpl<Instruction *> &DeadInstructions,
     const DenseMap<Instruction *, Instruction *> &SinkAfter) {
 
-  // Hold a mapping from predicated instructions to their recipes, in order to
-  // fix their AlsoPack behavior if a user is determined to replicate and use a
-  // scalar instead of vector value.
-  DenseMap<Instruction *, VPReplicateRecipe *> PredInst2Recipe;
-
   SmallPtrSet<const InterleaveGroup<Instruction> *, 1> InterleaveGroups;
 
   VPRecipeBuilder RecipeBuilder(OrigLoop, TLI, Legal, CM, PSE, Builder);
@@ -8803,8 +8802,8 @@ VPlanPtr LoopVectorizationPlanner::buildVPlanWithVPRecipes(
 
       // Otherwise, if all widening options failed, Instruction is to be
       // replicated. This may create a successor for VPBB.
-      VPBasicBlock *NextVPBB = RecipeBuilder.handleReplication(
-          Instr, Range, VPBB, PredInst2Recipe, Plan);
+      VPBasicBlock *NextVPBB =
+          RecipeBuilder.handleReplication(Instr, Range, VPBB, Plan);
       if (NextVPBB != VPBB) {
         VPBB = NextVPBB;
         VPBB->setName(BB->hasName() ? BB->getName() + "." + Twine(VPBBsForBB++)

diff  --git a/llvm/lib/Transforms/Vectorize/VPRecipeBuilder.h b/llvm/lib/Transforms/Vectorize/VPRecipeBuilder.h
index 985bf8579ab4..89c7b127d3ba 100644
--- a/llvm/lib/Transforms/Vectorize/VPRecipeBuilder.h
+++ b/llvm/lib/Transforms/Vectorize/VPRecipeBuilder.h
@@ -162,7 +162,6 @@ class VPRecipeBuilder {
   /// \p Range.Start to \p Range.End.
   VPBasicBlock *handleReplication(
       Instruction *I, VFRange &Range, VPBasicBlock *VPBB,
-      DenseMap<Instruction *, VPReplicateRecipe *> &PredInst2Recipe,
       VPlanPtr &Plan);
 };
 } // end namespace llvm

diff  --git a/llvm/lib/Transforms/Vectorize/VPlan.h b/llvm/lib/Transforms/Vectorize/VPlan.h
index 5a23c6839982..9b5d5d7e77be 100644
--- a/llvm/lib/Transforms/Vectorize/VPlan.h
+++ b/llvm/lib/Transforms/Vectorize/VPlan.h
@@ -1221,6 +1221,8 @@ class VPReplicateRecipe : public VPRecipeBase, public VPValue {
   bool isUniform() const { return IsUniform; }
 
   bool isPacked() const { return AlsoPack; }
+
+  bool isPredicated() const { return IsPredicated; }
 };
 
 /// A recipe for generating conditional branches on the bits of a mask.