[llvm] [VPlan] Add const to VPPredicator methods. nfc (PR #184359)

[Mel Chen via llvm-commits]

https://github.com/Mel-Chen updated https://github.com/llvm/llvm-project/pull/184359

>From 6f1c1e42a91ea66439e21ba2ad34cf2f4f8e328b Mon Sep 17 00:00:00 2001
From: Mel Chen <mel.chen at sifive.com>
Date: Tue, 3 Mar 2026 06:18:14 -0800
Subject: [PATCH] [VPlan] Add const for VPlanPredicator. nfc

---
 .../Transforms/Vectorize/VPlanPredicator.cpp    | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/llvm/lib/Transforms/Vectorize/VPlanPredicator.cpp b/llvm/lib/Transforms/Vectorize/VPlanPredicator.cpp
index ad4fd69882f30..1ab29d5140661 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanPredicator.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanPredicator.cpp
@@ -32,21 +32,21 @@ class VPPredicator {
   using EdgeMaskCacheTy =
       DenseMap<std::pair<const VPBasicBlock *, const VPBasicBlock *>,
                VPValue *>;
-  using BlockMaskCacheTy = DenseMap<VPBasicBlock *, VPValue *>;
+  using BlockMaskCacheTy = DenseMap<const VPBasicBlock *, VPValue *>;
   EdgeMaskCacheTy EdgeMaskCache;
 
   BlockMaskCacheTy BlockMaskCache;
 
   /// Create an edge mask for every destination of cases and/or default.
-  void createSwitchEdgeMasks(VPInstruction *SI);
+  void createSwitchEdgeMasks(const VPInstruction *SI);
 
   /// Computes and return the predicate of the edge between \p Src and \p Dst,
   /// possibly inserting new recipes at \p Dst (using Builder's insertion point)
-  VPValue *createEdgeMask(VPBasicBlock *Src, VPBasicBlock *Dst);
+  VPValue *createEdgeMask(const VPBasicBlock *Src, const VPBasicBlock *Dst);
 
   /// Record \p Mask as the *entry* mask of \p VPBB, which is expected to not
   /// already have a mask.
-  void setBlockInMask(VPBasicBlock *VPBB, VPValue *Mask) {
+  void setBlockInMask(const VPBasicBlock *VPBB, VPValue *Mask) {
     // TODO: Include the masks as operands in the predicated VPlan directly to
     // avoid keeping the map of masks beyond the predication transform.
     assert(!getBlockInMask(VPBB) && "Mask already set");
@@ -64,7 +64,7 @@ class VPPredicator {
 
 public:
   /// Returns the *entry* mask for \p VPBB.
-  VPValue *getBlockInMask(VPBasicBlock *VPBB) const {
+  VPValue *getBlockInMask(const VPBasicBlock *VPBB) const {
     return BlockMaskCache.lookup(VPBB);
   }
 
@@ -85,7 +85,8 @@ class VPPredicator {
 };
 } // namespace
 
-VPValue *VPPredicator::createEdgeMask(VPBasicBlock *Src, VPBasicBlock *Dst) {
+VPValue *VPPredicator::createEdgeMask(const VPBasicBlock *Src,
+                                      const VPBasicBlock *Dst) {
   assert(is_contained(Dst->getPredecessors(), Src) && "Invalid edge");
 
   // Look for cached value.
@@ -175,8 +176,8 @@ void VPPredicator::createHeaderMask(VPBasicBlock *HeaderVPBB, bool FoldTail) {
   setBlockInMask(HeaderVPBB, BlockMask);
 }
 
-void VPPredicator::createSwitchEdgeMasks(VPInstruction *SI) {
-  VPBasicBlock *Src = SI->getParent();
+void VPPredicator::createSwitchEdgeMasks(const VPInstruction *SI) {
+  const VPBasicBlock *Src = SI->getParent();
 
   // Create masks where SI is a switch. We create masks for all edges from SI's
   // parent block at the same time. This is more efficient, as we can create and