[PATCH] LoongArch: Add LA32 pointer guard support

[魏祎晗]

From f493e834ec4affef287e0e7352426f11fec83bc9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=AD=8F=E7=A5=8E=E6=99=97?= <aqwyh@buaa.edu.cn>
Date: Sun, 23 Aug 2026 03:40:42 +0800
Subject: [PATCH] LoongArch: Add LA32 pointer guard support
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The pointer guard assembly only implemented the 64-bit path using rotri.d.  LA32 lacks rotri.w, so implement the 32-bit branch using srli.w/slli.w/or to perform the rotation.

Signed-off-by: 魏祎晗 <aqwyh@buaa.edu.cn>
---
 .../unix/sysv/linux/loongarch/pointer_guard-asm.h   | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/sysdeps/unix/sysv/linux/loongarch/pointer_guard-asm.h b/sysdeps/unix/sysv/linux/loongarch/pointer_guard-asm.h
index 24e27e4092..8fe71b5aee 100644
--- a/sysdeps/unix/sysv/linux/loongarch/pointer_guard-asm.h
+++ b/sysdeps/unix/sysv/linux/loongarch/pointer_guard-asm.h
@@ -36,12 +36,25 @@
   PTR_MANGLE_LOAD (guard); \
   PTR_DEMANGLE2 (dst, src, guard);
 /* Use PTR_MANGLE2 for efficiency if guard is already loaded.  */
+# if __loongarch_grlen == 64
 # define PTR_MANGLE2(dst, src, guard) \
   xor  dst, src, guard; \
   rotri.d  dst, dst, 47;
 # define PTR_DEMANGLE2(dst, src, guard) \
   rotri.d  src, src, 17; \
   xor  dst, src, guard;
+# else
+# define PTR_MANGLE2(dst, src, guard) \
+  xor  dst, src, guard; \
+  srli.w  t2, dst, 23; \
+  slli.w  dst, dst, 9; \
+  or  dst, dst, t2;
+# define PTR_DEMANGLE2(dst, src, guard) \
+  srli.w  t2, src, 9; \
+  slli.w  src, src, 23; \
+  or  src, src, t2; \
+  xor  dst, src, guard;
+# endif
 #endif
 
 #endif /* POINTER_GUARD_ASM_H */
-- 
2.55.0