[llvm] [RISC-V] Adjust trampoline code for branch control flow protection (PR #141949)

[Craig Topper via llvm-commits]

topperc wrote:

> There is a change to use software-guarded jump (t2) in the trampoline code, the new stack of the test is now
> 
> ```
>    56 $ra
>    44 $a0      f
>    36 $a1      p
>    32 00038067 jalr  t2
>    28 010e3e03 ld    t3, 16(t3)
>    24 018e3383 ld    t2, 24(t3)
>    20 00000e17 auipc t3, 0
> sp+16 00000023 lpad  0
> ```

Is gcc going to make the same change?

https://github.com/llvm/llvm-project/pull/141949