[llvm] Hint for branch likelihood (PR #67972)

[Giulio Eulisse via llvm-commits]

https://github.com/ktf created https://github.com/llvm/llvm-project/pull/67972

None

>From 154f82bd0e35e9d8ad8f8812ba3eb1cf8d211003 Mon Sep 17 00:00:00 2001
From: Giulio Eulisse <10544+ktf at users.noreply.github.com>
Date: Mon, 2 Oct 2023 13:01:14 +0200
Subject: [PATCH] Hint for branch likelihood

---
 llvm/include/llvm/ADT/PagedVector.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/llvm/include/llvm/ADT/PagedVector.h b/llvm/include/llvm/ADT/PagedVector.h
index 667bece6d718385..f8d014c9c84dab6 100644
--- a/llvm/include/llvm/ADT/PagedVector.h
+++ b/llvm/include/llvm/ADT/PagedVector.h
@@ -84,7 +84,7 @@ template <typename T, size_t PageSize = 1024 / sizeof(T)> class PagedVector {
     assert(Index / PageSize < PageToDataPtrs.size());
     T *&PagePtr = PageToDataPtrs[Index / PageSize];
     // If the page was not yet allocated, allocate it.
-    if (!PagePtr) {
+    if (LLVM_UNLIKELY(!PagePtr)) {
       PagePtr = Allocator.getPointer()->template Allocate<T>(PageSize);
       // We need to invoke the default constructor on all the elements of the
       // page.