[glibc] LoongArch: Fix intermittent nptl/tst-cancel32 failure

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=4b0c2842a85f2f3cbe4aa11bd8aea18487982ba8

commit 4b0c2842a85f2f3cbe4aa11bd8aea18487982ba8
Author: mengqinggang <[email protected]>
Date:   Wed Aug 5 16:03:34 2026 +0800

    LoongArch: Fix intermittent nptl/tst-cancel32 failure
    
    The nptl/tst-cancel32 test fails intermittently on LoongArch
    with SIGSEGV at __longjmp:
    
    0x7ffff7de7f6c <__longjmp+28>   rotri.d         $sp, $t0, 0x11
    0x7ffff7de7f70 <__longjmp+32>   xor             $sp, $sp, $t1
    
    rotri.d and xor are expanded from PTR_DEMANGLE2.
    If the thread is cancelled between the rotri.d and xor,
    an incomplete sp register causes the SIGSEGV.
    
    Change the destination register of rotri.d to avoid an incomplete sp.

Diff:
---
 sysdeps/unix/sysv/linux/loongarch/pointer_guard-asm.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sysdeps/unix/sysv/linux/loongarch/pointer_guard-asm.h b/sysdeps/unix/sysv/linux/loongarch/pointer_guard-asm.h
index 75498545cb..24e27e4092 100644
--- a/sysdeps/unix/sysv/linux/loongarch/pointer_guard-asm.h
+++ b/sysdeps/unix/sysv/linux/loongarch/pointer_guard-asm.h
@@ -40,8 +40,8 @@
   xor  dst, src, guard; \
   rotri.d  dst, dst, 47;
 # define PTR_DEMANGLE2(dst, src, guard) \
-  rotri.d  dst, src, 17; \
-  xor  dst, dst, guard;
+  rotri.d  src, src, 17; \
+  xor  dst, src, guard;
 #endif
 
 #endif /* POINTER_GUARD_ASM_H */