[llvm] [OpenMP][OMPIRBuilder] Add support to omp target parallel (PR #67000)

[Johannes Doerfert via llvm-commits]

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@@ -1235,63 +1244,146 @@ IRBuilder<>::InsertPoint OpenMPIRBuilder::createParallel(
   }
 
   OutlineInfo OI;
-  OI.PostOutlineCB = [=](Function &OutlinedFn) {
-    // Add some known attributes.
-    OutlinedFn.addParamAttr(0, Attribute::NoAlias);
-    OutlinedFn.addParamAttr(1, Attribute::NoAlias);
-    OutlinedFn.addFnAttr(Attribute::NoUnwind);
-    OutlinedFn.addFnAttr(Attribute::NoRecurse);
-
-    assert(OutlinedFn.arg_size() >= 2 &&
-           "Expected at least tid and bounded tid as arguments");
-    unsigned NumCapturedVars =
-        OutlinedFn.arg_size() - /* tid & bounded tid */ 2;
-
-    CallInst *CI = cast<CallInst>(OutlinedFn.user_back());
-    CI->getParent()->setName("omp_parallel");
-    Builder.SetInsertPoint(CI);
-
-    // Build call __kmpc_fork_call[_if](Ident, n, microtask, var1, .., varn);
-    Value *ForkCallArgs[] = {
-        Ident, Builder.getInt32(NumCapturedVars),
-        Builder.CreateBitCast(&OutlinedFn, ParallelTaskPtr)};
-
-    SmallVector<Value *, 16> RealArgs;
-    RealArgs.append(std::begin(ForkCallArgs), std::end(ForkCallArgs));
-    if (IfCondition) {
-      Value *Cond = Builder.CreateSExtOrTrunc(IfCondition,
-                                              Type::getInt32Ty(M.getContext()));
-      RealArgs.push_back(Cond);
-    }
-    RealArgs.append(CI->arg_begin() + /* tid & bound tid */ 2, CI->arg_end());
-
-    // __kmpc_fork_call_if always expects a void ptr as the last argument
-    // If there are no arguments, pass a null pointer.
-    auto PtrTy = Type::getInt8PtrTy(M.getContext());
-    if (IfCondition && NumCapturedVars == 0) {
+  if (Config.isTargetDevice()) {
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jdoerfert wrote:

Should we try to outline at least one of those two cases? The conditional is really long now.

https://github.com/llvm/llvm-project/pull/67000