Isolating JITDbl2Ulng helper changes

[khushal1996]

Draft PR for testing purposes. No need for review at this time.

Isolating the helper function changes to make sure that the helper function is working fine. This is w.r.t. the draft PR #84384

This PR optimize the following cases:

---

Case	Previous Code	Optimized Instruction
float -> ulong	CORINFO_HELP_DBL2ULNG Helper	vcvttss2usi

public static UInt64 FloatToULong(float val)
{
    return (UInt64)val;
}

Assembly before optimization

G_M22196_IG01:              ;; offset=0000H
       4883EC28             sub      rsp, 40
       C5F877               vzeroupper 
						;; size=7 bbWeight=1 PerfScore 1.25
G_M22196_IG02:              ;; offset=0007H
       62F17E085AC0         vcvtss2sd xmm0, xmm0
       E87E57815E           call     CORINFO_HELP_DBL2ULNG
       90                   nop      
						;; size=12 bbWeight=1 PerfScore 5.25
G_M22196_IG03:              ;; offset=0013H
       4883C428             add      rsp, 40
       C3                   ret      
						;; size=5 bbWeight=1 PerfScore 1.25

Assembly afteroptimization

G_M22196_IG01:              ;; offset=0000H
       C5F877               vzeroupper 
						;; size=3 bbWeight=1 PerfScore 1.00
G_M22196_IG02:              ;; offset=0003H
       62F1FE0878C0         vcvttss2usi rax, xmm0
						;; size=6 bbWeight=1 PerfScore 6.00
G_M22196_IG03:              ;; offset=0009H
       C3                   ret

---

Case	Previous Code	Optimized Instruction
double -> ulong	CORINFO_HELP_DBL2ULNG Helper	vcvttsd2usi

public static UInt64 DoubleToULong(double val)
{
    return (UInt64)val;
}

Assembly before optimization

G_M30068_IG01:              ;; offset=0000H
       4883EC28             sub      rsp, 40
       C5F877               vzeroupper 
						;; size=7 bbWeight=1 PerfScore 1.25
G_M30068_IG02:              ;; offset=0007H
       E874577F5E           call     CORINFO_HELP_DBL2ULNG
       90                   nop      
						;; size=6 bbWeight=1 PerfScore 1.25
G_M30068_IG03:              ;; offset=000DH
       4883C428             add      rsp, 40
       C3                   ret

Assembly afteroptimization

G_M30068_IG01:              ;; offset=0000H
       C5F877               vzeroupper 
						;; size=3 bbWeight=1 PerfScore 1.00
G_M30068_IG02:              ;; offset=0003H
       62F1FF0878C0         vcvttsd2usi rax, xmm0
						;; size=6 bbWeight=1 PerfScore 5.00
G_M30068_IG03:              ;; offset=0009H
       C3                   ret

---

Case	Previous Code	Optimized Instruction
ulong -> double	vcvtsi2sd	vcvtusi2sd

public static double UIntToDouble(UInt64 val)
{
    return (double)val;
}

Assembly before optimization

G_M33997_IG01:              ;; offset=0000H
       C5F877               vzeroupper 
						;; size=3 bbWeight=1 PerfScore 1.00
G_M33997_IG02:              ;; offset=0003H
       62F17C0857C0         vxorps   xmm0, xmm0
       62F1FF082AC1         vcvtsi2sd  xmm0, rcx
       4885C9               test     rcx, rcx
       7D0A                 jge      SHORT G_M33997_IG03
       62F1FF08580502000000 vaddsd   xmm0, qword ptr [reloc @RWD00]
						;; size=27 bbWeight=1 PerfScore 12.58
G_M33997_IG03:              ;; offset=001EH
       C3                   ret

Assembly afteroptimization

G_M33997_IG01:              ;; offset=0000H
       C5F877               vzeroupper 
						;; size=3 bbWeight=1 PerfScore 1.00
G_M33997_IG02:              ;; offset=0003H
       62F1FF087BC1         vcvtusi2sd xmm0, rcx
						;; size=6 bbWeight=1 PerfScore 4.00
G_M33997_IG03:              ;; offset=0009H
       C3                   ret

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Issue Details

---

Draft PR for testing purposes. No need for review at this time.

Author:	khushal1996
Assignees:	-
Labels:	area-CodeGen-coreclr, community-contribution
Milestone:	-