[llvm] 405f914 - [SimplifyCFG] Check optforfuzzing attribute during in the pass implementation

[Arthur Eubanks via llvm-commits]

Author: Arthur Eubanks
Date: 2023-06-15T13:57:51-07:00
New Revision: 405f91475b37d509e82ac712d3d2c8274af314cc

URL: https://github.com/llvm/llvm-project/commit/405f91475b37d509e82ac712d3d2c8274af314cc
DIFF: https://github.com/llvm/llvm-project/commit/405f91475b37d509e82ac712d3d2c8274af314cc.diff

LOG: [SimplifyCFG] Check optforfuzzing attribute during in the pass implementation

Instead of setting the SimplifyCFGOptions options at the beginning of the pass.

Otherwise it always gets overriden by the pass and the value in SimplifyCFGOptions is ignored.

Added: 
    

Modified: 
    llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
    llvm/lib/Transforms/Utils/SimplifyCFG.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp b/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
index 0e8b3e8573abd..8ed3dcf1e6729 100644
--- a/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
+++ b/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
@@ -358,11 +358,6 @@ PreservedAnalyses SimplifyCFGPass::run(Function &F,
   DominatorTree *DT = nullptr;
   if (RequireAndPreserveDomTree)
     DT = &AM.getResult<DominatorTreeAnalysis>(F);
-  if (F.hasFnAttribute(Attribute::OptForFuzzing)) {
-    Options.setSimplifyCondBranch(false).setFoldTwoEntryPHINode(false);
-  } else {
-    Options.setSimplifyCondBranch(true).setFoldTwoEntryPHINode(true);
-  }
   if (!simplifyFunctionCFG(F, TTI, DT, Options))
     return PreservedAnalyses::all();
   PreservedAnalyses PA;
@@ -395,13 +390,6 @@ struct CFGSimplifyPass : public FunctionPass {
     DominatorTree *DT = nullptr;
     if (RequireAndPreserveDomTree)
       DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
-    if (F.hasFnAttribute(Attribute::OptForFuzzing)) {
-      Options.setSimplifyCondBranch(false)
-             .setFoldTwoEntryPHINode(false);
-    } else {
-      Options.setSimplifyCondBranch(true)
-             .setFoldTwoEntryPHINode(true);
-    }
 
     auto &TTI = getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
     return simplifyFunctionCFG(F, TTI, DT, Options);

diff  --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
index 6b512af994d54..a18b45f178c98 100644
--- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -6984,7 +6984,8 @@ bool SimplifyCFGOpt::simplifyCondBranch(BranchInst *BI, IRBuilder<> &Builder) {
       "Tautological conditional branch should have been eliminated already.");
 
   BasicBlock *BB = BI->getParent();
-  if (!Options.SimplifyCondBranch)
+  if (!Options.SimplifyCondBranch ||
+      BI->getFunction()->hasFnAttribute(Attribute::OptForFuzzing))
     return false;
 
   // Conditional branch
@@ -7275,7 +7276,8 @@ bool SimplifyCFGOpt::simplifyOnce(BasicBlock *BB) {
 
   IRBuilder<> Builder(BB);
 
-  if (Options.FoldTwoEntryPHINode) {
+  if (Options.FoldTwoEntryPHINode &&
+      !BB->getParent()->hasFnAttribute(Attribute::OptForFuzzing)) {
     // If there is a trivial two-entry PHI node in this basic block, and we can
     // eliminate it, do so now.
     if (auto *PN = dyn_cast<PHINode>(BB->begin()))