-mtp=cp15 generates __aeabi_read_tp in Thumb2 mode

[nathanchance]

Bugzilla Link	52329
Resolution	FIXED
Resolved on	Nov 08, 2021 08:41
Version	trunk
OS	Windows NT
Blocks	#4440 #51489
CC	@arndb,@nickdesaulniers,@smithp35,@tstellar
Fixed by commit(s)	d7e089f ed38280

Extended Description

This impacts the Linux kernel: ClangBuiltLinux/linux#1485

Reproducer: https://godbolt.org/z/aejoTqo4n

Fix: https://reviews.llvm.org/D112600

Opening this to track for LLVM 13.0.1.

[nathanchance]

assigned to @smithp35

[nathanchance]

Fixed: d7e089f

Leaving this open for LLVM 13.0.1 (as the kernel is expecting it to be picked there: https://lore.kernel.org/r/20211028083527.1057158-1-ardb@kernel.org/

[tstellar]

Hi Peter,

What is your opinion on backporting this?

https://reviews.llvm.org/rGd7e089f2d6a5cd5f283a90ab29241d20d4fc3ed1

[smithp35]

I think it should be fine to backport. The fix is straightfoward and the functionality is only enabled when the option is used so the risk is low.

[tstellar]

Merged: ed38280