[llvm] fc01c11 - [NFCI] Check for non-null before dereferencing a VPBB ptr (#190403)

[via llvm-commits]

Author: calebwat
Date: 2026-04-07T22:17:51+01:00
New Revision: fc01c111b94f43894b3099553bc0b0e42ef5de2c

URL: https://github.com/llvm/llvm-project/commit/fc01c111b94f43894b3099553bc0b0e42ef5de2c
DIFF: https://github.com/llvm/llvm-project/commit/fc01c111b94f43894b3099553bc0b0e42ef5de2c.diff

LOG: [NFCI] Check for non-null before dereferencing a VPBB ptr (#190403)

A VPBB variable is possibly null (defined via a ternary), but is
subsequently dereferenced without a check included. This patch adds a
check for it to avoid any possibly null dereference. This was found via
static analysis, there is not a known case right now where this issue is
hit.

Added: 
    

Modified: 
    llvm/lib/Transforms/Vectorize/VPlanUtils.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Vectorize/VPlanUtils.cpp b/llvm/lib/Transforms/Vectorize/VPlanUtils.cpp
index 04b6348665a05..e33a936dd9978 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanUtils.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanUtils.cpp
@@ -402,18 +402,19 @@ bool vputils::isUniformAcrossVFsAndUFs(VPValue *V) {
   VPRecipeBase *R = V->getDefiningRecipe();
   VPBasicBlock *VPBB = R ? R->getParent() : nullptr;
   VPlan *Plan = VPBB ? VPBB->getPlan() : nullptr;
-  if (VPBB &&
-      (VPBB == Plan->getVectorPreheader() || VPBB == Plan->getEntry())) {
-    if (match(V->getDefiningRecipe(),
-              m_VPInstruction<VPInstruction::CanonicalIVIncrementForPart>()))
-      return false;
-    return all_of(R->operands(), isUniformAcrossVFsAndUFs);
-  }
+  if (VPBB) {
+    if ((VPBB == Plan->getVectorPreheader() || VPBB == Plan->getEntry())) {
+      if (match(V->getDefiningRecipe(),
+                m_VPInstruction<VPInstruction::CanonicalIVIncrementForPart>()))
+        return false;
+      return all_of(R->operands(), isUniformAcrossVFsAndUFs);
+    }
 
-  if (VPRegionBlock *EnclosingRegion = VPBB->getEnclosingLoopRegion()) {
-    // Canonical IV is uniform.
-    if (V == EnclosingRegion->getCanonicalIV())
-      return true;
+    if (VPRegionBlock *EnclosingRegion = VPBB->getEnclosingLoopRegion()) {
+      // Canonical IV is uniform.
+      if (V == EnclosingRegion->getCanonicalIV())
+        return true;
+    }
   }
 
   return TypeSwitch<const VPRecipeBase *, bool>(R)