[libc-commits] [libc] [libc] default NUM_TABLE_ENTRIES to a fixed value of 3 (PR #221807)

[Schrodinger ZHU Yifan via libc-commits]

https://github.com/SchrodingerZhu created https://github.com/llvm/llvm-project/pull/221807

6 (192 entries) is too large for 32-bit devices and can cause shift overflow. This PR sets the limit to 3 words.

>From 0d98376720a55c28e35f6da20327d2e51030f377 Mon Sep 17 00:00:00 2001
From: Schrodinger ZHU Yifan <yifanzhu at rochester.edu>
Date: Mon, 7 Sep 2026 12:30:30 -0700
Subject: [PATCH] [libc] default NUM_TABLE_ENTRIES to a fixed value of 3

6 (192 entries) is too large for 32-bit devices and can cause shift overflow.
---
 libc/src/__support/tlsf_table.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libc/src/__support/tlsf_table.h b/libc/src/__support/tlsf_table.h
index a302fba15f11c..e75f1074ca4b3 100644
--- a/libc/src/__support/tlsf_table.h
+++ b/libc/src/__support/tlsf_table.h
@@ -32,7 +32,7 @@ struct DefaultFreeStoreConfig {
   static constexpr size_t UNIT_SIZE = BlockRef::MIN_ALIGN;
   static constexpr size_t STEP_SIZE_BITS = 3;
   static constexpr size_t NUM_STEP_BITS = 2;
-  static constexpr size_t NUM_TABLE_ENTRIES = sizeof(uintptr_t) == 8 ? 3 : 6;
+  static constexpr size_t NUM_TABLE_ENTRIES = 3;
   static constexpr bool USE_TRIE_FOR_OVERFLOW_BIN = true;
   static constexpr size_t LINEAR_SCAN_LIMIT = 16;
 };