restrict constant -> instruction upgrade to kernel/a specified function

Author: agozillon

llvm/include/llvm/IR/ReplaceConstant.h

@@ -18,10 +18,12 @@ namespace llvm {
 
 template <typename T> class ArrayRef;
 class Constant;
+class Function;
 
 /// Replace constant expressions users of the given constants with
 /// instructions. Return whether anything was changed.
 bool convertUsersOfConstantsToInstructions(ArrayRef<Constant *> Consts,
+                                           Function *RestrictToFunc = nullptr,
                                            bool RemoveDeadConstants = true);
 
 } // end namespace llvm

llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp

@@ -5187,7 +5187,7 @@ static Function *createOutlinedFunction(
     // from MLIR to LLVM-IR and the MLIR lowering may still require the original
     // constants we have created rewritten versions of.
     if (auto *Const = dyn_cast<Constant>(Input))
-      convertUsersOfConstantsToInstructions({Const}, false);
+      convertUsersOfConstantsToInstructions({Const}, Func, false);
 
     // Collect all the instructions
     for (User *User : make_early_inc_range(Input->users()))

llvm/lib/IR/ReplaceConstant.cpp

@@ -50,6 +50,7 @@ static SmallVector<Instruction *, 4> expandUser(BasicBlock::iterator InsertPt,
 }
 
 bool convertUsersOfConstantsToInstructions(ArrayRef<Constant *> Consts,
+                                           Function *RestrictToFunc,
                                            bool RemoveDeadConstants) {
   // Find all expandable direct users of Consts.
   SmallVector<Constant *> Stack;
@@ -75,7 +76,8 @@ bool convertUsersOfConstantsToInstructions(ArrayRef<Constant *> Consts,
   for (Constant *C : ExpandableUsers)
     for (User *U : C->users())
       if (auto *I = dyn_cast<Instruction>(U))
-        InstructionWorklist.insert(I);
+        if (!RestrictToFunc || I->getFunction() == RestrictToFunc)
+          InstructionWorklist.insert(I);
 
   // Replace those expandable operands with instructions
   bool Changed = false;