[llvm] [VPlan] Add m_VScale() pattern matcher. (NFC) (PR #207394)

[Florian Hahn via llvm-commits]

https://github.com/fhahn updated https://github.com/llvm/llvm-project/pull/207394

>From 142cc55bc75450b0874ff650af6c185cfaa0dc0c Mon Sep 17 00:00:00 2001
From: Florian Hahn <flo at fhahn.com>
Date: Fri, 3 Jul 2026 09:38:06 +0100
Subject: [PATCH] [VPlan] Add m_VScale() pattern matcher. (NFC)

Add a dedicated m_VScale() matcher for VPInstruction::VScale, in line
with other VPInstruction matchers.
---
 llvm/lib/Transforms/Vectorize/VPlanPatternMatch.h |  4 ++++
 llvm/lib/Transforms/Vectorize/VPlanUtils.cpp      | 11 ++++-------
 2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/llvm/lib/Transforms/Vectorize/VPlanPatternMatch.h b/llvm/lib/Transforms/Vectorize/VPlanPatternMatch.h
index e2e08c50d06e8..48c395b1102f1 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanPatternMatch.h
+++ b/llvm/lib/Transforms/Vectorize/VPlanPatternMatch.h
@@ -1077,6 +1077,10 @@ inline auto m_WidenIntrinsic(const T &...Ops) {
   return m_Isa<VPWidenIntrinsicRecipe>(m_Intrinsic<IntrID>(Ops...));
 }
 
+inline VPInstruction_match<VPInstruction::VScale> m_VScale() {
+  return m_VPInstruction<VPInstruction::VScale>();
+}
+
 inline auto m_LiveIn() { return m_Isa<VPIRValue, VPSymbolicValue>(); }
 
 /// Match a GEP recipe (VPWidenGEPRecipe, VPInstruction, or VPReplicateRecipe)
diff --git a/llvm/lib/Transforms/Vectorize/VPlanUtils.cpp b/llvm/lib/Transforms/Vectorize/VPlanUtils.cpp
index 747a44c6e3a8d..c686fd9907795 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanUtils.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanUtils.cpp
@@ -694,8 +694,7 @@ VPInstruction *vputils::findCanonicalIVIncrement(VPlan &Plan) {
     VPSymbolicValue &UF = Plan.getUF();
     if (!UF.isMaterialized())
       return Step == &UF ||
-             match(Step, m_c_Mul(m_Specific(&Plan.getUF()),
-                                 m_VPInstruction<VPInstruction::VScale>()));
+             match(Step, m_c_Mul(m_Specific(&Plan.getUF()), m_VScale()));
 
     // Alias masking: step is number of active lanes of a dependence mask.
     if (match(Step, m_ZExtOrTruncOrSelf(
@@ -709,15 +708,13 @@ VPInstruction *vputils::findCanonicalIVIncrement(VPlan &Plan) {
 
     // Scalable VF: step involves VScale.
     if (ConcreteUF == 1)
-      return match(Step, m_VPInstruction<VPInstruction::VScale>());
-    if (match(Step, m_c_Mul(m_SpecificInt(ConcreteUF),
-                            m_VPInstruction<VPInstruction::VScale>())))
+      return match(Step, m_VScale());
+    if (match(Step, m_c_Mul(m_SpecificInt(ConcreteUF), m_VScale())))
       return true;
     // mul(VScale, ConcreteUF) may have been simplified to
     // shl(VScale, log2(ConcreteUF)) when ConcreteUF is a power of 2.
     return isPowerOf2_32(ConcreteUF) &&
-           match(Step, m_Shl(m_VPInstruction<VPInstruction::VScale>(),
-                             m_SpecificInt(Log2_32(ConcreteUF))));
+           match(Step, m_Shl(m_VScale(), m_SpecificInt(Log2_32(ConcreteUF))));
   };
 
   VPInstruction *Increment = nullptr;