[llvm] [CodeExtractor] Resolving the Inconsistency of Compiled Binary Files (PR #86497)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-transforms

Author: dong jianqiang (dongjianqiang2)

<details>
<summary>Changes</summary>

When the compiler enables ALSR by default, binary inconsistency occurs when the extractCodeRegion function is called. The reason is that the sequence of traversing ExitBlocks containers of the SmallPtrSet type is changed due to randomization of BasicBlock pointers. 
This fixes https://github.com/llvm/llvm-project/issues/86427

---
Full diff: https://github.com/llvm/llvm-project/pull/86497.diff


2 Files Affected:

- (modified) llvm/include/llvm/Transforms/Utils/CodeExtractor.h (+1-1) 
- (modified) llvm/lib/Transforms/Utils/CodeExtractor.cpp (+2-2) 


``````````diff
diff --git a/llvm/include/llvm/Transforms/Utils/CodeExtractor.h b/llvm/include/llvm/Transforms/Utils/CodeExtractor.h
index 27b34ef023db72..333ed6774d6c7e 100644
--- a/llvm/include/llvm/Transforms/Utils/CodeExtractor.h
+++ b/llvm/include/llvm/Transforms/Utils/CodeExtractor.h
@@ -249,7 +249,7 @@ class CodeExtractorAnalysisCache {
                        Instruction *Addr, BasicBlock *ExitBlock) const;
 
     void severSplitPHINodesOfEntry(BasicBlock *&Header);
-    void severSplitPHINodesOfExits(const SmallPtrSetImpl<BasicBlock *> &Exits);
+    void severSplitPHINodesOfExits(const SetVector<BasicBlock *> &Exits);
     void splitReturnBlocks();
 
     Function *constructFunction(const ValueSet &inputs,
diff --git a/llvm/lib/Transforms/Utils/CodeExtractor.cpp b/llvm/lib/Transforms/Utils/CodeExtractor.cpp
index 3191751d92e176..6988292ac71561 100644
--- a/llvm/lib/Transforms/Utils/CodeExtractor.cpp
+++ b/llvm/lib/Transforms/Utils/CodeExtractor.cpp
@@ -745,7 +745,7 @@ void CodeExtractor::severSplitPHINodesOfEntry(BasicBlock *&Header) {
 /// and other with remaining incoming blocks; then first PHIs are placed in
 /// outlined region.
 void CodeExtractor::severSplitPHINodesOfExits(
-    const SmallPtrSetImpl<BasicBlock *> &Exits) {
+    const SetVector<BasicBlock *> &Exits) {
   for (BasicBlock *ExitBB : Exits) {
     BasicBlock *NewBB = nullptr;
 
@@ -1751,7 +1751,7 @@ CodeExtractor::extractCodeRegion(const CodeExtractorAnalysisCache &CEAC,
   // Calculate the exit blocks for the extracted region and the total exit
   // weights for each of those blocks.
   DenseMap<BasicBlock *, BlockFrequency> ExitWeights;
-  SmallPtrSet<BasicBlock *, 1> ExitBlocks;
+  SetVector<BasicBlock *> ExitBlocks;
   for (BasicBlock *Block : Blocks) {
     for (BasicBlock *Succ : successors(Block)) {
       if (!Blocks.count(Succ)) {

``````````

</details>


https://github.com/llvm/llvm-project/pull/86497