[llvm] [VPlan] Extend licm to hoist replicate loads (PR #179506)

[Ramkumar Ramachandra via llvm-commits]

================
@@ -2695,7 +2723,9 @@ static void licm(VPlan &Plan) {
   for (VPBasicBlock *VPBB : VPBlockUtils::blocksOnly<VPBasicBlock>(
            vp_depth_first_shallow(LoopRegion->getEntry()))) {
     for (VPRecipeBase &R : make_early_inc_range(*VPBB)) {
-      if (cannotHoistOrSinkRecipe(R))
+      if (cannotHoistOrSinkRecipe(R, LoadGroups,
+                                  LoopRegion->getEntryBasicBlock(),
+                                  LoopRegion->getExitingBasicBlock()))
----------------
artagnon wrote:

Ah, yes -- the corresponding check is hasLoopInvariantOperands, a helper we don't have:

```cpp
      if (CurLoop->hasLoopInvariantOperands(&I) &&
          canSinkOrHoistInst(I, AA, DT, CurLoop, MSSAU, true, Flags, ORE) &&
          isSafeToExecuteUnconditionally(I, DT, TLI, CurLoop, SafetyInfo, ORE,
                                         Preheader->getTerminator(), AC,
                                         AllowSpeculation)) {
```

https://github.com/llvm/llvm-project/pull/179506