[clang] 2ac696e - [clang][bytecode] Try to avoid a `SmallVector` in `Pointer::toAPValue()` (#226143)

[via cfe-commits]

Author: Timm Baeder
Date: 2026-09-24T15:24:28+02:00
New Revision: 2ac696e23ca31d68a89060c7a935c75bc4efb846

URL: https://github.com/llvm/llvm-project/commit/2ac696e23ca31d68a89060c7a935c75bc4efb846
DIFF: https://github.com/llvm/llvm-project/commit/2ac696e23ca31d68a89060c7a935c75bc4efb846.diff

LOG: [clang][bytecode] Try to avoid a `SmallVector` in `Pointer::toAPValue()` (#226143)

Only create the local variable if we really need it.

Added: 
    

Modified: 
    clang/lib/AST/ByteCode/Pointer.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/AST/ByteCode/Pointer.cpp b/clang/lib/AST/ByteCode/Pointer.cpp
index 552cdf1bf8ec7..0f564306704a6 100644
--- a/clang/lib/AST/ByteCode/Pointer.cpp
+++ b/clang/lib/AST/ByteCode/Pointer.cpp
@@ -251,17 +251,16 @@ bool Pointer::operator==(const Pointer &P) const {
 }
 
 APValue Pointer::toAPValue(const ASTContext &ASTCtx) const {
-  llvm::SmallVector<APValue::LValuePathEntry, 5> Path;
 
   if (isZero())
-    return APValue(APValue::LValueBase(), CharUnits::Zero(), Path,
+    return APValue(APValue::LValueBase(), CharUnits::Zero(), {},
                    /*IsOnePastEnd=*/false, /*IsNullPtr=*/true);
 
   switch (StorageKind) {
   case Storage::Int:
     return APValue(static_cast<const Expr *>(nullptr),
                    CharUnits::fromQuantity(asIntPointer().Value + this->Offset),
-                   Path,
+                   {},
                    /*IsOnePastEnd=*/false, /*IsNullPtr=*/false);
   case Storage::Block:
     // See below.
@@ -281,13 +280,15 @@ APValue Pointer::toAPValue(const ASTContext &ASTCtx) const {
                    CharUnits::Zero(), {},
                    /*OnePastTheEnd=*/false, /*IsNull=*/false);
   } break;
-  case Storage::String:
+  case Storage::String: {
+    llvm::SmallVector<APValue::LValuePathEntry, 1> Path;
     if (Offset != 0 || Str.Decayed)
       Path.push_back(APValue::LValuePathEntry::ArrayIndex(Offset));
 
     return APValue(APValue::LValueBase(Str.Base),
                    CharUnits::fromQuantity(Offset * elemSize()), Path,
                    /*OnePastTheEnd=*/false, /*IsNull=*/false);
+  }
   case Storage::Opaque: {
     bool ValidBase = Opaque.hasValidBase() || this->Offset <= 1;
 
@@ -307,6 +308,7 @@ APValue Pointer::toAPValue(const ASTContext &ASTCtx) const {
     // For valid bases, assemble the LValuePath.
     APValue Result;
     if (ValidBase) {
+      llvm::SmallVector<APValue::LValuePathEntry, 5> Path;
       for (const PointerPathEntry &Entry : Opaque.path()) {
         switch (Entry.Kind) {
         case PointerPathEntry::Field:
@@ -368,6 +370,7 @@ APValue Pointer::toAPValue(const ASTContext &ASTCtx) const {
   // Build the path into the object.
   bool OnePastEnd = isOnePastEnd() && !isZeroSizeArray();
 
+  llvm::SmallVector<APValue::LValuePathEntry, 5> Path;
   PtrView Ptr = view();
   while (Ptr.isField() || Ptr.isArrayElement()) {