[Scalar] Use LLVMContext::MD_mem_parallel_loop_access directly (NFC) (#69549)

This patch "constant propagates"
LLVMContext::MD_mem_parallel_loop_access into wherever
ParallelLoopAccessMDKind is used.

Author: kazutakahirata

llvm/lib/Transforms/Scalar/Scalarizer.cpp

@@ -282,12 +282,10 @@ T getWithDefaultOverride(const cl::opt<T> &ClOption,
 
 class ScalarizerVisitor : public InstVisitor<ScalarizerVisitor, bool> {
 public:
-  ScalarizerVisitor(unsigned ParallelLoopAccessMDKind, DominatorTree *DT,
-                    ScalarizerPassOptions Options)
-      : ParallelLoopAccessMDKind(ParallelLoopAccessMDKind), DT(DT),
-        ScalarizeVariableInsertExtract(
-            getWithDefaultOverride(ClScalarizeVariableInsertExtract,
-                                   Options.ScalarizeVariableInsertExtract)),
+  ScalarizerVisitor(DominatorTree *DT, ScalarizerPassOptions Options)
+      : DT(DT), ScalarizeVariableInsertExtract(getWithDefaultOverride(
+                    ClScalarizeVariableInsertExtract,
+                    Options.ScalarizeVariableInsertExtract)),
         ScalarizeLoadStore(getWithDefaultOverride(ClScalarizeLoadStore,
                                                   Options.ScalarizeLoadStore)),
         ScalarizeMinBits(getWithDefaultOverride(ClScalarizeMinBits,
@@ -337,8 +335,6 @@ class ScalarizerVisitor : public InstVisitor<ScalarizerVisitor, bool> {
 
   SmallVector<WeakTrackingVH, 32> PotentiallyDeadInstrs;
 
-  unsigned ParallelLoopAccessMDKind;
-
   DominatorTree *DT;
 
   const bool ScalarizeVariableInsertExtract;
@@ -448,8 +444,7 @@ bool ScalarizerLegacyPass::runOnFunction(Function &F) {
     return false;
 
   DominatorTree *DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
-  ScalarizerVisitor Impl(LLVMContext::MD_mem_parallel_loop_access, DT,
-                         ScalarizerPassOptions());
+  ScalarizerVisitor Impl(DT, ScalarizerPassOptions());
   return Impl.visit(F);
 }
 
@@ -556,7 +551,7 @@ bool ScalarizerVisitor::canTransferMetadata(unsigned Tag) {
           || Tag == LLVMContext::MD_invariant_load
           || Tag == LLVMContext::MD_alias_scope
           || Tag == LLVMContext::MD_noalias
-          || Tag == ParallelLoopAccessMDKind
+          || Tag == LLVMContext::MD_mem_parallel_loop_access
           || Tag == LLVMContext::MD_access_group);
 }
 
@@ -1253,7 +1248,7 @@ bool ScalarizerVisitor::finish() {
 
 PreservedAnalyses ScalarizerPass::run(Function &F, FunctionAnalysisManager &AM) {
   DominatorTree *DT = &AM.getResult<DominatorTreeAnalysis>(F);
-  ScalarizerVisitor Impl(LLVMContext::MD_mem_parallel_loop_access, DT, Options);
+  ScalarizerVisitor Impl(DT, Options);
   bool Changed = Impl.visit(F);
   PreservedAnalyses PA;
   PA.preserve<DominatorTreeAnalysis>();