[WIP] Optimize CastHelpers method for performance

[Copilot]

Thanks for asking me to work on this. I will get started on it and keep this PR's description up to date as I form a plan and make progress.

; Assembly listing for method System.Runtime.CompilerServices.CastHelpers:StelemRef(System.Array,long,System.Object) (Tier1)
; Emitting BLENDED_CODE for X64 with AVX - Windows
; Tier1 code
; optimized code
; rsp based frame
; fully interruptible
; No PGO data
; 0 inlinees with PGO data; 2 single block inlinees; 0 inlinees without PGO data

G_M000_IG01: ;; offset=0x0000
sub rsp, 40

G_M000_IG02: ;; offset=0x0004
mov eax, dword ptr [rcx+0x08]
cmp rdx, rax
jae SHORT G_M000_IG10
lea rax, bword ptr [rcx+8*rdx+0x10]
mov rdx, qword ptr [rcx]
mov rdx, qword ptr [rdx+0x30]
test r8, r8
je SHORT G_M000_IG06

G_M000_IG03: ;; offset=0x001D
cmp rdx, qword ptr [r8]
jne SHORT G_M000_IG08

G_M000_IG04: ;; offset=0x0022
mov rcx, rax
mov rdx, r8

G_M000_IG05: ;; offset=0x0028
add rsp, 40
jmp System.Runtime.CompilerServices.CastHelpers:WriteBarrier(byref,System.Object)

G_M000_IG06: ;; offset=0x0031
xor rcx, rcx
mov gword ptr [rax], rcx

G_M000_IG07: ;; offset=0x0036
add rsp, 40
ret

G_M000_IG08: ;; offset=0x003B
mov r10, 0x7FFC7D01C4D8
cmp qword ptr [rcx], r10
je SHORT G_M000_IG04
mov rcx, rax

G_M000_IG09: ;; offset=0x004D
add rsp, 40
tail.jmp [System.Runtime.CompilerServices.CastHelpers:StelemRef_Helper(byref,ulong,System.Object)]

G_M000_IG10: ;; offset=0x0057
call CORINFO_HELP_RNGCHKFAIL
int3

; Total bytes of code 93

; Assembly listing for method System.Runtime.CompilerServices.CastHelpers:LdelemaRef(System.Array,long,ulong):byref (Tier1)
; Emitting BLENDED_CODE for X64 with AVX - Windows
; Tier1 code
; optimized code
; rsp based frame
; partially interruptible
; No PGO data
; 0 inlinees with PGO data; 1 single block inlinees; 0 inlinees without PGO data

G_M000_IG01: ;; offset=0x0000
sub rsp, 40

G_M000_IG02: ;; offset=0x0004
mov eax, dword ptr [rcx+0x08]
cmp rdx, rax
jae SHORT G_M000_IG05
lea rax, bword ptr [rcx+8*rdx+0x10]
mov rcx, qword ptr [rcx]
cmp qword ptr [rcx+0x30], r8
jne SHORT G_M000_IG04

G_M000_IG03: ;; offset=0x001A
add rsp, 40
ret

G_M000_IG04: ;; offset=0x001F
call [System.Runtime.CompilerServices.CastHelpers:ThrowArrayMismatchException():byref]
int3

G_M000_IG05: ;; offset=0x0026
call CORINFO_HELP_RNGCHKFAIL
int3

; Total bytes of code 44

; Assembly listing for method ConsoleApp1.DemoService:Main() (MinOpts)
; Emitting BLENDED_CODE for X64 with AVX - Windows
; MinOpts code
; debuggable code
; rbp based frame
; fully interruptible
; No PGO data

G_M000_IG01: ;; offset=0x0000
push rbp
push rdi
sub rsp, 40
lea rbp, [rsp+0x30]

G_M000_IG02: ;; offset=0x000B
cmp dword ptr [(reloc 0x7ffc7d16e328)], 0
je SHORT G_M000_IG04

G_M000_IG03: ;; offset=0x0014
call CORINFO_HELP_DBG_IS_JUST_MY_CODE

G_M000_IG04: ;; offset=0x0019
mov rcx, 0x150001004A0
mov rdx, 0x15000100008
call [MyInterceptorNamespace.<CallerFullNameInterceptors_g>F8A1E273C8BFA75940BE2801949B9CC6C8A69D09F0A9863E82EB3B1D02C61D464__CallerFullNameInterceptors:Intercept_ConsoleApp1_LogHelper_Log_10_19(System.String,System.String)]
nop

G_M000_IG05: ;; offset=0x0034
add rsp, 40
pop rdi
pop rbp
ret

; Total bytes of code 59

; Assembly listing for method MyInterceptorNamespace.<CallerFullNameInterceptors_g>F8A1E273C8BFA75940BE2801949B9CC6C8A69D09F0A9863E82EB3B1D02C61D464__CallerFullNameInterceptors:Intercept_ConsoleApp1_LogHelper_Log_10_19(System.String,System.String) (MinOpts)
; Emitting BLENDED_CODE for X64 with AVX - Windows
; MinOpts code
; debuggable code
; rbp based frame
; fully interruptible
; No PGO data

G_M000_IG01: ;; offset=0x0000
push rbp
push rdi
sub rsp, 40
lea rbp, [rsp+0x30]
mov gword ptr [rbp+0x10], rcx
mov gword ptr [rbp+0x18], rdx

G_M000_IG02: ;; offset=0x0013
cmp dword ptr [(reloc 0x7ffc7d16e328)], 0
je SHORT G_M000_IG04

G_M000_IG03: ;; offset=0x001C
call CORINFO_HELP_DBG_IS_JUST_MY_CODE

G_M000_IG04: ;; offset=0x0021
mov rcx, gword ptr [rbp+0x10]
mov rdx, 0x150001004D0
call [ConsoleApp1.LogHelper:Log(System.String,System.String)]
nop

G_M000_IG05: ;; offset=0x0036
add rsp, 40
pop rdi
pop rbp
ret

; Total bytes of code 61

; Assembly listing for method ConsoleApp1.LogHelper:Log(System.String,System.String) (MinOpts)
; Emitting BLENDED_CODE for X64 with AVX - Windows
; MinOpts code
; debuggable code
; rbp based frame
; fully interruptible
; No PGO data

G_M000_IG01: ;; offset=0x0000
push rbp
push rdi
sub rsp, 40
lea rbp, [rsp+0x30]
xor eax, eax
mov qword ptr [rbp-0x10], rax
mov gword ptr [rbp+0x10], rcx
mov gword ptr [rbp+0x18], rdx

G_M000_IG02: ;; offset=0x0019
cmp dword ptr [(reloc 0x7ffc7d16e328)], 0
je SHORT G_M000_IG04

G_M000_IG03: ;; offset=0x0022
call CORINFO_HELP_DBG_IS_JUST_MY_CODE

G_M000_IG04: ;; offset=0x0027
mov rcx, gword ptr [rbp+0x18]
mov r8, gword ptr [rbp+0x10]
mov rdx, 0x15000100210
call [System.String:Concat(System.String,System.String,System.String):System.String]
mov gword ptr [rbp-0x10], rax
mov rcx, gword ptr [rbp-0x10]
call [System.Console:WriteLine(System.String)]
nop

G_M000_IG05: ;; offset=0x004E
add rsp, 40
pop rdi
pop rbp
ret

; Total bytes of code 85

检查这个JIT输出, 告诉我为何它没有成功内联

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