From b3779ef424adbf8011c89eec030ed77075fe4a0c Mon Sep 17 00:00:00 2001
From: Sanjoy Das <sanjoy@playingwithpointers.com>
Date: Tue, 5 Mar 2019 01:15:08 +0000
Subject: [PATCH] PHI nodes are not `FPMathOperator` s

Reviewers: chandlerc, arsenm

Reviewed By: arsenm

Subscribers: wdng, arsenm, mcrosier, jlebar, bixia, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58887

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@355362 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/IR/Operator.h        | 1 +
 lib/Analysis/IVDescriptors.cpp    | 3 +--
 unittests/IR/InstructionsTest.cpp | 9 +++++++++
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/include/llvm/IR/Operator.h b/include/llvm/IR/Operator.h
index 613d4342ef5..fefb13c66d4 100644
--- a/include/llvm/IR/Operator.h
+++ b/include/llvm/IR/Operator.h
@@ -379,6 +379,7 @@ public:
     case Instruction::ExtractElement:
     case Instruction::ShuffleVector:
     case Instruction::InsertElement:
+    case Instruction::PHI:
       return false;
     default:
       return V->getType()->isFPOrFPVectorTy();
diff --git a/lib/Analysis/IVDescriptors.cpp b/lib/Analysis/IVDescriptors.cpp
index a452a52b94d..555e3c9ed45 100644
--- a/lib/Analysis/IVDescriptors.cpp
+++ b/lib/Analysis/IVDescriptors.cpp
@@ -549,9 +549,8 @@ RecurrenceDescriptor::isConditionalRdxPattern(
 RecurrenceDescriptor::InstDesc
 RecurrenceDescriptor::isRecurrenceInstr(Instruction *I, RecurrenceKind Kind,
                                         InstDesc &Prev, bool HasFunNoNaNAttr) {
-  bool FP = I->getType()->isFloatingPointTy();
   Instruction *UAI = Prev.getUnsafeAlgebraInst();
-  if (!UAI && FP && !I->isFast())
+  if (!UAI && isa<FPMathOperator>(I) && !I->isFast())
     UAI = I; // Found an unsafe (unvectorizable) algebra instruction.
 
   switch (I->getOpcode()) {
diff --git a/unittests/IR/InstructionsTest.cpp b/unittests/IR/InstructionsTest.cpp
index 94f37251e60..3b2bd6fa81b 100644
--- a/unittests/IR/InstructionsTest.cpp
+++ b/unittests/IR/InstructionsTest.cpp
@@ -993,5 +993,14 @@ TEST(InstructionsTest, SkipDebug) {
   EXPECT_EQ(nullptr, Term->getNextNonDebugInstruction());
 }
 
+TEST(InstructionsTest, PhiIsNotFPMathOperator) {
+  LLVMContext Context;
+  IRBuilder<> Builder(Context);
+  MDBuilder MDHelper(Context);
+  Instruction *I = Builder.CreatePHI(Builder.getDoubleTy(), 0);
+  EXPECT_FALSE(isa<FPMathOperator>(I));
+  I->deleteValue();
+}
+
 } // end anonymous namespace
 } // end namespace llvm
-- 
2.50.1