From 4b19cccbb5d8d77750da96cef2daefa6c28b0e37 Mon Sep 17 00:00:00 2001
From: Florian Hahn <flo@fhahn.com>
Date: Sat, 18 Jul 2020 15:59:51 +0100
Subject: [PATCH] [PredicateInfo] Fold PredicateWithCondition into
 PredicateBase (NFC).

Each concrete instance of a predicate has a condition (also noted in the
original PredicateBase comment) and to me it seems like there is no
clear benefit of having both PredicateBase and PredicateWithCondition
and they can be folded together.

Reviewers: nikic, efriedma

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D84089
---
 llvm/include/llvm/Transforms/Utils/PredicateInfo.h | 24 ++++++++--------------
 llvm/lib/Transforms/Scalar/NewGVN.cpp              |  6 +-----
 2 files changed, 10 insertions(+), 20 deletions(-)

diff --git a/llvm/include/llvm/Transforms/Utils/PredicateInfo.h b/llvm/include/llvm/Transforms/Utils/PredicateInfo.h
index 657b97c..cdac414 100644
--- a/llvm/include/llvm/Transforms/Utils/PredicateInfo.h
+++ b/llvm/include/llvm/Transforms/Utils/PredicateInfo.h
@@ -83,37 +83,31 @@ public:
   // predicates, this is different to OriginalOp which refers to the initial
   // operand.
   Value *RenamedOp;
+  // The condition associated with this predicate.
+  Value *Condition;
+
   PredicateBase(const PredicateBase &) = delete;
   PredicateBase &operator=(const PredicateBase &) = delete;
   PredicateBase() = delete;
   virtual ~PredicateBase() = default;
-
-protected:
-  PredicateBase(PredicateType PT, Value *Op) : Type(PT), OriginalOp(Op) {}
-};
-
-class PredicateWithCondition : public PredicateBase {
-public:
-  Value *Condition;
   static bool classof(const PredicateBase *PB) {
     return PB->Type == PT_Assume || PB->Type == PT_Branch ||
            PB->Type == PT_Switch;
   }
 
 protected:
-  PredicateWithCondition(PredicateType PT, Value *Op, Value *Condition)
-      : PredicateBase(PT, Op), Condition(Condition) {}
+  PredicateBase(PredicateType PT, Value *Op, Value *Condition)
+      : Type(PT), OriginalOp(Op), Condition(Condition) {}
 };
 
 // Provides predicate information for assumes.  Since assumes are always true,
 // we simply provide the assume instruction, so you can tell your relative
 // position to it.
-class PredicateAssume : public PredicateWithCondition {
+class PredicateAssume : public PredicateBase {
 public:
   IntrinsicInst *AssumeInst;
   PredicateAssume(Value *Op, IntrinsicInst *AssumeInst, Value *Condition)
-      : PredicateWithCondition(PT_Assume, Op, Condition),
-        AssumeInst(AssumeInst) {}
+      : PredicateBase(PT_Assume, Op, Condition), AssumeInst(AssumeInst) {}
   PredicateAssume() = delete;
   static bool classof(const PredicateBase *PB) {
     return PB->Type == PT_Assume;
@@ -123,7 +117,7 @@ public:
 // Mixin class for edge predicates.  The FROM block is the block where the
 // predicate originates, and the TO block is the block where the predicate is
 // valid.
-class PredicateWithEdge : public PredicateWithCondition {
+class PredicateWithEdge : public PredicateBase {
 public:
   BasicBlock *From;
   BasicBlock *To;
@@ -135,7 +129,7 @@ public:
 protected:
   PredicateWithEdge(PredicateType PType, Value *Op, BasicBlock *From,
                     BasicBlock *To, Value *Cond)
-      : PredicateWithCondition(PType, Op, Cond), From(From), To(To) {}
+      : PredicateBase(PType, Op, Cond), From(From), To(To) {}
 };
 
 // Provides predicate information for branches.
diff --git a/llvm/lib/Transforms/Scalar/NewGVN.cpp b/llvm/lib/Transforms/Scalar/NewGVN.cpp
index 0ed1773..45d01cc 100644
--- a/llvm/lib/Transforms/Scalar/NewGVN.cpp
+++ b/llvm/lib/Transforms/Scalar/NewGVN.cpp
@@ -1539,12 +1539,8 @@ NewGVN::performSymbolicPredicateInfoEvaluation(Instruction *I) const {
 
   LLVM_DEBUG(dbgs() << "Found predicate info from instruction !\n");
 
-  auto *PWC = dyn_cast<PredicateWithCondition>(PI);
-  if (!PWC)
-    return nullptr;
-
   auto *CopyOf = I->getOperand(0);
-  auto *Cond = PWC->Condition;
+  auto *Cond = PI->Condition;
 
   // If this a copy of the condition, it must be either true or false depending
   // on the predicate info type and edge.
-- 
2.7.4