From: Chad Rosier <mcrosier@codeaurora.org>
Date: Thu, 10 Aug 2017 14:12:57 +0000 (+0000)
Subject: [NewGVN] Add CL option to control the generation of phi-of-ops (disable by default).
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=0db3a4f0417ad000835e08b00dca1046c050ee23;p=llvm

[NewGVN] Add CL option to control the generation of phi-of-ops (disable by default).

Differential Revision: https://reviews.llvm.org/D36478539

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310594 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/Scalar/NewGVN.cpp b/lib/Transforms/Scalar/NewGVN.cpp
index e620ae9c557..ceb53502f98 100644
--- a/lib/Transforms/Scalar/NewGVN.cpp
+++ b/lib/Transforms/Scalar/NewGVN.cpp
@@ -127,6 +127,10 @@ DEBUG_COUNTER(PHIOfOpsCounter, "newgvn-phi",
 static cl::opt<bool> EnableStoreRefinement("enable-store-refinement",
                                            cl::init(false), cl::Hidden);
 
+/// Currently, the generation "phi of ops" can result in correctness issues.
+static cl::opt<bool> EnablePhiOfOps("enable-phi-of-ops", cl::init(false),
+                                    cl::Hidden);
+
 //===----------------------------------------------------------------------===//
 //                                GVN Pass
 //===----------------------------------------------------------------------===//
@@ -2442,6 +2446,8 @@ void NewGVN::addPhiOfOps(PHINode *Op, BasicBlock *BB,
 }
 
 static bool okayForPHIOfOps(const Instruction *I) {
+  if (!EnablePhiOfOps)
+    return false;
   return isa<BinaryOperator>(I) || isa<SelectInst>(I) || isa<CmpInst>(I) ||
          isa<LoadInst>(I);
 }
diff --git a/test/Transforms/NewGVN/completeness.ll b/test/Transforms/NewGVN/completeness.ll
index 1798bfea5fe..0b5a13ec2ed 100644
--- a/test/Transforms/NewGVN/completeness.ll
+++ b/test/Transforms/NewGVN/completeness.ll
@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -basicaa -newgvn -S | FileCheck %s
+; RUN: opt < %s -basicaa -newgvn -enable-phi-of-ops=true -S | FileCheck %s
 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
 
 define i32 @test1(i32, i8**) {
diff --git a/test/Transforms/NewGVN/pr33461.ll b/test/Transforms/NewGVN/pr33461.ll
index 0a41d6834a4..90587e40ff1 100644
--- a/test/Transforms/NewGVN/pr33461.ll
+++ b/test/Transforms/NewGVN/pr33461.ll
@@ -1,6 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
 ;; Ensure the store verifier is not overzealous
-; RUN: opt -newgvn -S %s | FileCheck %s
+; RUN: opt -newgvn -enable-phi-of-ops=true -S %s | FileCheck %s
 @b = external global i16, align 2
 
 define void @patatino() {
diff --git a/test/Transforms/NewGVN/storeoverstore.ll b/test/Transforms/NewGVN/storeoverstore.ll
index 28f5eea03ce..2117d0ee060 100644
--- a/test/Transforms/NewGVN/storeoverstore.ll
+++ b/test/Transforms/NewGVN/storeoverstore.ll
@@ -1,6 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt -newgvn -S < %s | FileCheck %s
-; RUN: opt -passes=newgvn -S -o - %s | FileCheck %s
+; RUN: opt -newgvn -enable-phi-of-ops=true -S < %s | FileCheck %s
+; RUN: opt -passes=newgvn -enable-phi-of-ops=true -S -o - %s | FileCheck %s
 
 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"