[llvm] [llvm] Replace `OwningArrayRef` with `std::vector` in `BTFParser` (PR #169124)

[David Stone via llvm-commits]

https://github.com/davidstone created https://github.com/llvm/llvm-project/pull/169124

`OwningArrayRef` requires that the size and the capacity are the same. This prevents reusing memory allocations unless the size happens to be exactly the same (which is rare enough we don't even try). Switch to `std::vector` instead so that we're not repeatedly calling `new[]` and `delete[]`.

>From 3a3f129553947bcbe84558c9865bf554e033caea Mon Sep 17 00:00:00 2001
From: David Stone <davidfromonline at gmail.com>
Date: Fri, 21 Nov 2025 15:43:27 -0700
Subject: [PATCH] [llvm] Replace `OwningArrayRef` with `std::vector` in
 `BTFParser`

`OwningArrayRef` requires that the size and the capacity are the same. This prevents reusing memory allocations unless the size happens to be exactly the same (which is rare enough we don't even try). Switch to `std::vector` instead so that we're not repeatedly calling `new[]` and `delete[]`.
---
 llvm/include/llvm/DebugInfo/BTF/BTFParser.h | 2 +-
 llvm/lib/DebugInfo/BTF/BTFParser.cpp        | 5 +++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/llvm/include/llvm/DebugInfo/BTF/BTFParser.h b/llvm/include/llvm/DebugInfo/BTF/BTFParser.h
index f8b5b29738b3f..32644e6700e78 100644
--- a/llvm/include/llvm/DebugInfo/BTF/BTFParser.h
+++ b/llvm/include/llvm/DebugInfo/BTF/BTFParser.h
@@ -46,7 +46,7 @@ class BTFParser {
   // A copy of types table from the object file but using native byte
   // order. Should not be too big in practice, e.g. for ~250MiB vmlinux
   // image it is ~4MiB.
-  OwningArrayRef<uint8_t> TypesBuffer;
+  std::vector<uint8_t> TypesBuffer;
 
   // Maps ELF section number to instruction line number information.
   // Each BTFLinesVector is sorted by `InsnOffset` to allow fast lookups.
diff --git a/llvm/lib/DebugInfo/BTF/BTFParser.cpp b/llvm/lib/DebugInfo/BTF/BTFParser.cpp
index 4fc31a4456031..971a0d9f01769 100644
--- a/llvm/lib/DebugInfo/BTF/BTFParser.cpp
+++ b/llvm/lib/DebugInfo/BTF/BTFParser.cpp
@@ -206,7 +206,8 @@ Error BTFParser::parseTypesInfo(ParseContext &Ctx, uint64_t TypesInfoStart,
                                 StringRef RawData) {
   using support::endian::byte_swap;
 
-  TypesBuffer = OwningArrayRef<uint8_t>(arrayRefFromStringRef(RawData));
+  auto RawDataAsBytes = arrayRefFromStringRef(RawData);
+  TypesBuffer.assign(RawDataAsBytes.begin(), RawDataAsBytes.end());
   // Switch endianness if necessary.
   endianness Endianness = Ctx.Obj.isLittleEndian() ? llvm::endianness::little
                                                    : llvm::endianness::big;
@@ -380,7 +381,7 @@ Error BTFParser::parse(const ObjectFile &Obj, const ParseOptions &Opts) {
   SectionLines.clear();
   SectionRelocs.clear();
   Types.clear();
-  TypesBuffer = OwningArrayRef<uint8_t>();
+  TypesBuffer.clear();
 
   ParseContext Ctx(Obj, Opts);
   std::optional<SectionRef> BTF;