[llvm-branch-commits] [llvm] release/20.x: [CoroSplit] Always erase lifetime intrinsics for spilled allocas (#142551) (PR #147448)

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llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-coroutines

@llvm/pr-subscribers-llvm-transforms

Author: None (llvmbot)

<details>
<summary>Changes</summary>

Backport 038dc2c63b2db744be6afeea74b18be4938149e9

Requested by: @<!-- -->ChuanqiXu9

---
Full diff: https://github.com/llvm/llvm-project/pull/147448.diff


1 Files Affected:

- (modified) llvm/lib/Transforms/Coroutines/CoroFrame.cpp (+9-12) 


``````````diff
diff --git a/llvm/lib/Transforms/Coroutines/CoroFrame.cpp b/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
index 68edabb083be3..35832b594e9a3 100644
--- a/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
+++ b/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
@@ -1213,11 +1213,17 @@ static void insertSpills(const FrameDataInfo &FrameData, coro::Shape &Shape) {
   for (const auto &A : FrameData.Allocas) {
     AllocaInst *Alloca = A.Alloca;
     UsersToUpdate.clear();
-    for (User *U : Alloca->users()) {
+    for (User *U : make_early_inc_range(Alloca->users())) {
       auto *I = cast<Instruction>(U);
-      if (DT.dominates(Shape.CoroBegin, I))
+      // It is meaningless to retain the lifetime intrinsics refer for the
+      // member of coroutine frames and the meaningless lifetime intrinsics
+      // are possible to block further optimizations.
+      if (I->isLifetimeStartOrEnd())
+        I->eraseFromParent();
+      else if (DT.dominates(Shape.CoroBegin, I))
         UsersToUpdate.push_back(I);
     }
+
     if (UsersToUpdate.empty())
       continue;
     auto *G = GetFramePointer(Alloca);
@@ -1231,17 +1237,8 @@ static void insertSpills(const FrameDataInfo &FrameData, coro::Shape &Shape) {
     for (auto *DVR : DbgVariableRecords)
       DVR->replaceVariableLocationOp(Alloca, G);
 
-    for (Instruction *I : UsersToUpdate) {
-      // It is meaningless to retain the lifetime intrinsics refer for the
-      // member of coroutine frames and the meaningless lifetime intrinsics
-      // are possible to block further optimizations.
-      if (I->isLifetimeStartOrEnd()) {
-        I->eraseFromParent();
-        continue;
-      }
-
+    for (Instruction *I : UsersToUpdate)
       I->replaceUsesOfWith(Alloca, G);
-    }
   }
   Builder.SetInsertPoint(&*Shape.getInsertPtAfterFramePtr());
   for (const auto &A : FrameData.Allocas) {

``````````

</details>


https://github.com/llvm/llvm-project/pull/147448