JIT: AssertProp propagates const vector back to loop body

[EgorBo]

Minimal repro from #70336 (comment)

static int Test()
{
    var cns = Vector128.Create(1, 2, 3, 4);

    int i = 0;
    do
    {
        i = (cns + Vector128.Create(i)).ToScalar();
    } 
    while (i < 100);

    return i;
}

Despite the fact I declared the constant vector outside of the loop it ends up inside leading to a memory load each iteration:

x64:

; Method C:Test():int
G_M43325_IG01:
       vzeroupper 
G_M43325_IG02:
       xor      eax, eax
       align    [11 bytes for IG03]
G_M43325_IG03:
       vmovd    xmm0, eax
       vpbroadcastd xmm0, xmm0
       vpaddd   xmm0, xmm0, xmmword ptr [reloc @RWD00]
       vmovd    eax, xmm0
       cmp      eax, 100
       jl       SHORT G_M43325_IG03
G_M43325_IG04:
       ret      
RWD00  	dq	0000000200000001h, 0000000400000003h
; Total bytes of code: 43

Arm64:

; Method C:Test():int
G_M43325_IG01:
            stp     fp, lr, [sp,#-16]!
            mov     fp, sp
G_M43325_IG02:
            mov     w0, wzr
G_M43325_IG03:
            dup     v16.4s, w0
            ldr     q17, [@RWD00]
            add     v16.4s, v17.4s, v16.4s
            smov    x0, v16.s[0]
            cmp     w0, #100
            blt     G_M43325_IG03
G_M43325_IG04:
            ldp     fp, lr, [sp],#16
            ret     lr
RWD00  	dq	0000000200000001h, 0000000400000003h
; Total bytes of code: 44

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Issue Details

---

Minimal repro from #70336 (comment)

static int Test()
{
    var cns = Vector128.Create(1, 2, 3, 4);

    int i = 0;
    do
    {
        i = (cns + Vector128.Create(i)).ToScalar();
    } 
    while (i < 100);

    return i;
}

Despite the fact I declared the constant vector outside of the loop it ends up inside leading to a memory load each iteration:

x64:

; Method C:Test():int
G_M43325_IG01:
       vzeroupper 
G_M43325_IG02:
       xor      eax, eax
       align    [11 bytes for IG03]
G_M43325_IG03:
       vmovd    xmm0, eax
       vpbroadcastd xmm0, xmm0
       vpaddd   xmm0, xmm0, xmmword ptr [reloc @RWD00]
       vmovd    eax, xmm0
       cmp      eax, 100
       jl       SHORT G_M43325_IG03
G_M43325_IG04:
       ret      
RWD00  	dq	0000000200000001h, 0000000400000003h
; Total bytes of code: 43

Arm64:

; Method C:Test():int
G_M43325_IG01:
            stp     fp, lr, [sp,#-16]!
            mov     fp, sp
G_M43325_IG02:
            mov     w0, wzr
G_M43325_IG03:
            dup     v16.4s, w0
            ldr     q17, [@RWD00]
            add     v16.4s, v17.4s, v16.4s
            smov    x0, v16.s[0]
            cmp     w0, #100
            blt     G_M43325_IG03
G_M43325_IG04:
            ldp     fp, lr, [sp],#16
            ret     lr
RWD00  	dq	0000000200000001h, 0000000400000003h
; Total bytes of code: 44

Author:	EgorBo
Assignees:	-
Labels:	area-CodeGen-coreclr
Milestone:	-