[mono][jit] Fuse SIMD extract and insert on arm64

[jandupej]

Arm64 has the ins instruction which is capable of inserting from a specific lane into another lane. This PR takes advantage of this and fuses constant extract with constant insert (or elementwise constructor). Only float and double vectors are affected, as the appropriate mono operations for int types are missing. This change affects only mini, not LLVM.

This code:

private static Vector128<float> DUT1(Vector128<float> x)
{
    return Vector128.Create(
        Vector128.GetElement(x, 1),
        Vector128.GetElement(x, 2),
        Vector128.GetElement(x, 3),
        Vector128.GetElement(x, 0)); 
}

Would compile into:

0000000000000000        stp     x29, x30, [sp, #-0x30]!
0000000000000004        mov     x29, sp
0000000000000008        stp     x0, x1, [x29, #0x20]
000000000000000c        ldr     q0, [x29, #0x20]
0000000000000010        dup.4s  v4, v0[1]
0000000000000014        dup.4s  v3, v0[2]
0000000000000018        dup.4s  v2, v0[3]
000000000000001c        dup.4s  v1, v0[0]
0000000000000020        eor.16b v0, v0, v0
0000000000000024        mov.s   v0[0], v4[0]
0000000000000028        mov.s   v0[1], v3[0]
000000000000002c        mov.s   v0[2], v2[0]
0000000000000030        mov.s   v0[3], v1[0]
0000000000000034        str     q0, [x29, #0x10]
0000000000000038        ldp     x0, x1, [x29, #0x10]
000000000000003c        mov     sp, x29
0000000000000040        ldp     x29, x30, [sp], #0x30
0000000000000044        ret

Current codegen is:

0000000000000000        stp     x29, x30, [sp, #-0x30]!
0000000000000004        mov     x29, sp
0000000000000008        stp     x0, x1, [x29, #0x20]
000000000000000c        eor.16b v0, v0, v0
0000000000000010        ldr     q1, [x29, #0x20]
0000000000000014        mov.s   v0[0], v1[1]
0000000000000018        mov.s   v0[1], v1[2]
000000000000001c        mov.s   v0[2], v1[3]
0000000000000020        mov.s   v0[3], v1[0]
0000000000000024        str     q0, [x29, #0x10]
0000000000000028        ldp     x0, x1, [x29, #0x10]
000000000000002c        mov     sp, x29
0000000000000030        ldp     x29, x30, [sp], #0x30
0000000000000034        ret

Addresses #85166.

[SamMonoRT]

/azp run

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[fanyang-mono]

LGTM!

[jandupej]

CI failures seem unrelated. Merging.