[llvm-branch-commits] [clang] [llvm] [mlir] [OMPIRBuilder] Add support for explicit deallocation points (PR #154752)

[Sergio Afonso via llvm-branch-commits]

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@@ -1835,20 +1835,21 @@ void CodeGenFunction::EmitOMPParallelDirective(const OMPParallelDirective &S) {
     const CapturedStmt *CS = S.getCapturedStmt(OMPD_parallel);
     const Stmt *ParallelRegionBodyStmt = CS->getCapturedStmt();
 
-    auto BodyGenCB = [&, this](InsertPointTy AllocaIP,
-                               InsertPointTy CodeGenIP) {
+    auto BodyGenCB = [&, this](InsertPointTy AllocIP, InsertPointTy CodeGenIP,
+                               ArrayRef<InsertPointTy> DeallocIPs) {
       OMPBuilderCBHelpers::EmitOMPOutlinedRegionBody(
-          *this, ParallelRegionBodyStmt, AllocaIP, CodeGenIP, "parallel");
+          *this, ParallelRegionBodyStmt, AllocIP, CodeGenIP, "parallel");
       return llvm::Error::success();
     };
 
     CGCapturedStmtInfo CGSI(*CS, CR_OpenMP);
     CodeGenFunction::CGCapturedStmtRAII CapInfoRAII(*this, &CGSI);
     llvm::OpenMPIRBuilder::InsertPointTy AllocaIP(
         AllocaInsertPt->getParent(), AllocaInsertPt->getIterator());
-    llvm::OpenMPIRBuilder::InsertPointTy AfterIP = cantFail(
-        OMPBuilder.createParallel(Builder, AllocaIP, BodyGenCB, PrivCB, FiniCB,
-                                  IfCond, NumThreads, ProcBind, S.hasCancel()));
+    llvm::OpenMPIRBuilder::InsertPointTy AfterIP =
+        cantFail(OMPBuilder.createParallel(
+            Builder, AllocaIP, /*DeallocIPs=*/{}, BodyGenCB, PrivCB, FiniCB,
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skatrak wrote:

At the moment, the only code path that uses the `DeallocIPs` is the one outlining the parallel region for a target device, so this call in Clang doesn't use it.

If at some point explicit allocations were introduced for the host at the `AllocaIP` and the list here remained empty, the default deallocation point would be the exit block of the parallel region inside of the outlined function (see the `CodeExtractor` when `DeallocationBlocks.empty()`, for reference). That could potentially be wrong, if the `AllocaIP` happened to be located outside of the outlined region.

https://github.com/llvm/llvm-project/pull/154752