From aeb0fdff351b6142eef3db5ce5033bfcb1d093e6 Mon Sep 17 00:00:00 2001
From: Arthur Eubanks <aeubanks@google.com>
Date: Fri, 13 Nov 2020 18:34:34 -0800
Subject: [PATCH] [SimplifyCFG] Respect optforfuzzing in NPM pass

Regression caused by refactoring in
cdd006eec9409923f9a56b9026ce2cb72e7b71dc.

See discussion in https://reviews.llvm.org/D89917.

Reviewed By: arsenm, morehouse

Differential Revision: https://reviews.llvm.org/D91473
---
 llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp      | 5 +++++
 llvm/test/Transforms/SimplifyCFG/opt-for-fuzzing.ll | 1 +
 2 files changed, 6 insertions(+)

diff --git a/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp b/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
index 1798e017bfad..c36619211971 100644
--- a/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
+++ b/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
@@ -245,6 +245,11 @@ PreservedAnalyses SimplifyCFGPass::run(Function &F,
                                        FunctionAnalysisManager &AM) {
   auto &TTI = AM.getResult<TargetIRAnalysis>(F);
   Options.AC = &AM.getResult<AssumptionAnalysis>(F);
+  if (F.hasFnAttribute(Attribute::OptForFuzzing)) {
+    Options.setSimplifyCondBranch(false).setFoldTwoEntryPHINode(false);
+  } else {
+    Options.setSimplifyCondBranch(true).setFoldTwoEntryPHINode(true);
+  }
   if (!simplifyFunctionCFG(F, TTI, Options))
     return PreservedAnalyses::all();
   PreservedAnalyses PA;
diff --git a/llvm/test/Transforms/SimplifyCFG/opt-for-fuzzing.ll b/llvm/test/Transforms/SimplifyCFG/opt-for-fuzzing.ll
index 429f4a3f8544..4a0d9e884615 100644
--- a/llvm/test/Transforms/SimplifyCFG/opt-for-fuzzing.ll
+++ b/llvm/test/Transforms/SimplifyCFG/opt-for-fuzzing.ll
@@ -1,4 +1,5 @@
 ; RUN: opt < %s -simplifycfg -S | FileCheck %s
+; RUN: opt < %s -passes=simplifycfg -S | FileCheck %s
 
 define i32 @foo(i32 %x) optforfuzzing {
 entry: