JIT: Missed optimization for integer x / y; x % y

[BoyBaykiller]

For integers this is a common pattern

a = x / y;
b = x % y;

which currently generates (https://godbolt.org/z/nn3b4q57K):

mov      eax, edi
cdq      
idiv     edx:eax, esi          ; compute quotient and remainder
mov      dword ptr [r8], eax   ; a = quotient
mov      eax, edi
cdq      
idiv     edx:eax, esi          ; compute quotient and remainder
mov      dword ptr [rcx], edx  ; b = remainder

div already gives quotient and remainder so it should only be computed once here (https://godbolt.org/z/qKb8qEqzv):

mov     eax, edi
cdq
idiv    esi
mov     dword ptr [r8], eax
mov     dword ptr [rcx], edx

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[huoyaoyuan]

Duplicate of #5213. See also #45230.

Math.DivRem or X86Base.DivRem are the suggested approach.

[BoyBaykiller]

Ah I missed these issues and DivRem. It'd still be nice if this was handled in JIT