[JitDiff X64] [Copilot] [WIP] Remove unsafe code from WebHeaderEncoding

[MihuBot]

Job completed in 2 minutes 50 seconds (remote runner delay: 0 seconds).
dotnet/runtime#125592

Main commit: dotnet/runtime@c38f37a
PR commit: dotnet/runtime@e57c812

Diffs

Found 85 files with textual diffs.

Summary of Code Size diffs:
(Lower is better)

Total bytes of base: 45392490
Total bytes of diff: 45392556
Total bytes of delta: 66 (0.00 % of base)
Total relative delta: 0.58
    diff is a regression.
    relative diff is a regression.


Top file regressions (bytes):
          66 : System.Net.HttpListener.dasm (0.06 % of base)

1 total files with Code Size differences (0 improved, 1 regressed), 259 unchanged.

Top method regressions (bytes):
          66 (58.41 % of base) : System.Net.HttpListener.dasm - System.Net.WebHeaderEncoding:GetBytes(System.String,int,int,byte[],int) (FullOpts)

Top method regressions (percentages):
          66 (58.41 % of base) : System.Net.HttpListener.dasm - System.Net.WebHeaderEncoding:GetBytes(System.String,int,int,byte[],int) (FullOpts)

1 total methods with Code Size differences (0 improved, 1 regressed), 284676 unchanged.

--------------------------------------------------------------------------------

Artifacts:

• diff-frameworks.txt (986 B)
• ShortDiffsRegressions.md (9 KB)
• jit-diffs-pr.zip (155 MB)
• jit-diffs-main.zip (155 MB)

[MihuBot]

Top method regressions

66 (58.41 % of base) - System.Net.WebHeaderEncoding:GetBytes(System.String,int,int,byte[],int)

 ; Assembly listing for method System.Net.WebHeaderEncoding:GetBytes(System.String,int,int,byte[],int) (FullOpts)
 ; Emitting BLENDED_CODE for x64 + VEX + EVEX on Unix
 ; FullOpts code
 ; optimized code
 ; rbp based frame
 ; fully interruptible
 ; No PGO data
+; 0 inlinees with PGO data; 3 single block inlinees; 2 inlinees without PGO data
 ; Final local variable assignments
 ;
-;  V00 arg0         [V00,T03] (  4,  7   )     ref  ->  rdi         class-hnd single-def <System.String>
-;  V01 arg1         [V01,T02] (  7, 15   )     int  ->  registers  
-;  V02 arg2         [V02,T08] (  3,  2.50)     int  ->  rdx         single-def
-;  V03 arg3         [V03,T05] (  6,  4   )     ref  ->  rcx         class-hnd single-def <byte[]>
-;  V04 arg4         [V04,T09] (  3,  2.50)     int  ->   r8         single-def
-;  V05 loc0         [V05,T11] (  3,  1.50)    long  ->  rcx        
-;  V06 loc1         [V06    ] (  2,  1   )     ref  ->  [rbp-0x08]  must-init pinned class-hnd <byte[]>
-;  V07 loc2         [V07,T04] (  3,  8.50)    long  ->  registers  
-;  V08 loc3         [V08,T07] (  3,  5   )     int  ->  rdx        
-;# V09 OutArgs      [V09    ] (  1,  1   )  struct ( 0) [rsp+0x00]  do-not-enreg[XS] addr-exposed "OutgoingArgSpace" <Empty>
-;  V10 tmp1         [V10,T01] (  3, 24   )    long  ->  rcx         "impSpillLclRefs"
-;  V11 tmp2         [V11,T00] (  4, 32   )     int  ->  rsi         "impSpillLclRefs"
-;  V12 tmp3         [V12,T10] (  2,  2   )    long  ->  rcx         "Cast away GC"
-;  V13 cse0         [V13,T06] (  3,  6   )     int  ->  rax         "CSE #02: aggressive"
-;  V14 cse1         [V14,T12] (  2,  1   )     int  ->   r9         "CSE #01: moderate"
+;  V00 arg0         [V00,T03] (  5,  4   )     ref  ->  rdi         class-hnd single-def <System.String>
+;  V01 arg1         [V01,T06] (  4,  3   )     int  ->  rsi         single-def
+;  V02 arg2         [V02,T07] (  4,  3   )     int  ->  rdx         single-def
+;  V03 arg3         [V03,T04] (  5,  3.50)     ref  ->  rcx         class-hnd single-def <byte[]>
+;  V04 arg4         [V04,T05] (  5,  3.50)     int  ->   r8         single-def
+;* V05 loc0         [V05    ] (  0,  0   )  struct (16) zero-ref    ld-addr-op <System.ReadOnlySpan`1[char]>
+;* V06 loc1         [V06    ] (  0,  0   )  struct (16) zero-ref    ld-addr-op <System.Span`1[byte]>
+;  V07 loc2         [V07,T00] ( 11, 16.58)     int  ->  rsi        
+;# V08 OutArgs      [V08    ] (  1,  1   )  struct ( 0) [rsp+0x00]  do-not-enreg[XS] addr-exposed "OutgoingArgSpace" <Empty>
+;* V09 tmp1         [V09    ] (  0,  0   )  struct (16) zero-ref    "Inline return value spill temp" <System.ReadOnlySpan`1[char]>
+;* V10 tmp2         [V10    ] (  0,  0   )  struct (16) zero-ref    ld-addr-op "NewObj constructor temp" <System.ReadOnlySpan`1[char]>
+;* V11 tmp3         [V11    ] (  0,  0   )  struct (16) zero-ref    ld-addr-op "Inline ldloca(s) first use temp" <System.ReadOnlySpan`1[char]>
+;* V12 tmp4         [V12    ] (  0,  0   )   byref  ->  zero-ref    "Inlining Arg"
+;* V13 tmp5         [V13    ] (  0,  0   )  struct (16) zero-ref    ld-addr-op "NewObj constructor temp" <System.Span`1[byte]>
+;  V14 tmp6         [V14,T08] (  3,  4.50)   byref  ->  rax         single-def "field V05._reference (fldOffset=0x0)" P-INDEP
+;  V15 tmp7         [V15,T02] (  8,  7   )     int  ->  rdx         "field V05._length (fldOffset=0x8)" P-INDEP
+;  V16 tmp8         [V16,T09] (  3,  4.50)   byref  ->  rcx         single-def "field V06._reference (fldOffset=0x0)" P-INDEP
+;  V17 tmp9         [V17,T12] (  3,  1.04)     int  ->  rdi         "field V06._length (fldOffset=0x8)" P-INDEP
+;* V18 tmp10        [V18    ] (  0,  0   )   byref  ->  zero-ref    single-def "field V09._reference (fldOffset=0x0)" P-INDEP
+;* V19 tmp11        [V19    ] (  0,  0   )     int  ->  zero-ref    "field V09._length (fldOffset=0x8)" P-INDEP
+;  V20 tmp12        [V20,T13] (  2,  1   )   byref  ->  rax         single-def "field V10._reference (fldOffset=0x0)" P-INDEP
+;* V21 tmp13        [V21    ] (  0,  0   )     int  ->  zero-ref    "field V10._length (fldOffset=0x8)" P-INDEP
+;* V22 tmp14        [V22    ] (  0,  0   )   byref  ->  zero-ref    "field V11._reference (fldOffset=0x0)" P-INDEP
+;* V23 tmp15        [V23    ] (  0,  0   )     int  ->  zero-ref    "field V11._length (fldOffset=0x8)" P-INDEP
+;  V24 tmp16        [V24,T10] (  3,  1.50)   byref  ->  rcx         "field V13._reference (fldOffset=0x0)" P-INDEP
+;  V25 tmp17        [V25,T11] (  3,  1.50)     int  ->  rdi         "field V13._length (fldOffset=0x8)" P-INDEP
+;  V26 cse0         [V26,T01] (  3, 11.88)    long  ->  rdi         "CSE #05: aggressive"
 ;
-; Lcl frame size = 16
+; Lcl frame size = 0
 
 G_M43641_IG01:
        push     rbp
-       sub      rsp, 16
-       lea      rbp, [rsp+0x10]
-       xor      eax, eax
-       mov      qword ptr [rbp-0x08], rax
-						;; size=16 bbWeight=1 PerfScore 3.00
+       mov      rbp, rsp
+						;; size=4 bbWeight=1 PerfScore 1.25
 G_M43641_IG02:
-       mov      eax, dword ptr [rdi+0x08]
-       test     eax, eax
-       je       SHORT G_M43641_IG08
-						;; size=7 bbWeight=1 PerfScore 3.25
+       cmp      dword ptr [rdi+0x08], 0
+       je       SHORT G_M43641_IG07
+						;; size=6 bbWeight=1 PerfScore 4.00
 G_M43641_IG03:
-       mov      gword ptr [rbp-0x08], rcx
+       mov      eax, esi
+       mov      r9d, edx
+       add      rax, r9
+       mov      r9d, dword ptr [rdi+0x08]
+       cmp      rax, r9
+       ja       SHORT G_M43641_IG09
+       mov      eax, esi
+       lea      rax, bword ptr [rdi+2*rax+0x0C]
        test     rcx, rcx
        je       SHORT G_M43641_IG04
-       mov      r9d, dword ptr [rcx+0x08]
-       test     r9d, r9d
-       je       SHORT G_M43641_IG04
-       add      rcx, 16
+       mov      edi, r8d
+       mov      esi, edx
+       add      rdi, rsi
+       mov      esi, dword ptr [rcx+0x08]
+       cmp      rdi, rsi
+       ja       SHORT G_M43641_IG10
+       mov      r8d, r8d
+       lea      rcx, bword ptr [rcx+r8+0x10]
+       mov      edi, edx
        jmp      SHORT G_M43641_IG05
-       align    [0 bytes for IG06]
-						;; size=24 bbWeight=0.50 PerfScore 3.88
+       align    [10 bytes for IG06]
+						;; size=67 bbWeight=0.50 PerfScore 7.00
 G_M43641_IG04:
-       xor      ecx, ecx
-						;; size=2 bbWeight=0.50 PerfScore 0.12
+       or       r8d, edx
+       jne      SHORT G_M43641_IG10
+       xor      rcx, rcx
+       xor      edi, edi
+						;; size=9 bbWeight=0.50 PerfScore 0.88
 G_M43641_IG05:
-       movsxd   r8, r8d
-       add      rcx, r8
-       add      edx, esi
-       cmp      esi, edx
-       jge      SHORT G_M43641_IG07
-						;; size=12 bbWeight=0.50 PerfScore 1.00
+       xor      esi, esi
+       test     edx, edx
+       je       SHORT G_M43641_IG07
+       cmp      edx, edi
+       jg       SHORT G_M43641_IG08
+						;; size=10 bbWeight=0.50 PerfScore 1.38
 G_M43641_IG06:
-       lea      r8, [rcx+0x01]
-       lea      r9d, [rsi+0x01]
-       cmp      esi, eax
-       jae      SHORT G_M43641_IG09
-       mov      esi, esi
-       movzx    rsi, byte  ptr [rdi+2*rsi+0x0C]
-       mov      byte  ptr [rcx], sil
-       cmp      r9d, edx
-       mov      rcx, r8
-       mov      esi, r9d
+       mov      edi, esi
+       movzx    r8, byte  ptr [rax+2*rdi]
+       mov      byte  ptr [rcx+rdi], r8b
+       inc      esi
+       cmp      esi, edx
        jl       SHORT G_M43641_IG06
-						;; size=34 bbWeight=4 PerfScore 29.00
+						;; size=17 bbWeight=3.96 PerfScore 18.81
 G_M43641_IG07:
-       xor      rax, rax
-       mov      gword ptr [rbp-0x08], rax
-						;; size=6 bbWeight=0.50 PerfScore 0.62
-G_M43641_IG08:
-       add      rsp, 16
        pop      rbp
        ret      
-						;; size=6 bbWeight=1 PerfScore 1.75
+						;; size=2 bbWeight=1 PerfScore 1.50
+G_M43641_IG08:
+       cmp      esi, edi
+       jae      SHORT G_M43641_IG11
+       mov      r8d, esi
+       mov      r9d, esi
+       movzx    r9, byte  ptr [rax+2*r9]
+       mov      byte  ptr [rcx+r8], r9b
+       inc      esi
+       cmp      esi, edx
+       jl       SHORT G_M43641_IG08
+       jmp      SHORT G_M43641_IG07
+						;; size=27 bbWeight=0.04 PerfScore 0.33
 G_M43641_IG09:
+       mov      edi, 33
+       mov      rax, 0xD1FFAB1E      ; code for System.ThrowHelper:ThrowArgumentOutOfRangeException(int)
+       call     [rax]System.ThrowHelper:ThrowArgumentOutOfRangeException(int)
+       int3     
+						;; size=18 bbWeight=0 PerfScore 0.00
+G_M43641_IG10:
+       mov      rax, 0xD1FFAB1E      ; code for System.ThrowHelper:ThrowArgumentOutOfRangeException()
+       call     [rax]System.ThrowHelper:ThrowArgumentOutOfRangeException()
+       int3     
+						;; size=13 bbWeight=0 PerfScore 0.00
+G_M43641_IG11:
        call     CORINFO_HELP_RNGCHKFAIL
        int3     
 						;; size=6 bbWeight=0 PerfScore 0.00
 
-; Total bytes of code 113, prolog size 16, PerfScore 42.62, instruction count 41, allocated bytes for code 113 (MethodHash=4c335586) for method System.Net.WebHeaderEncoding:GetBytes(System.String,int,int,byte[],int) (FullOpts)
+; Total bytes of code 179, prolog size 4, PerfScore 35.14, instruction count 61, allocated bytes for code 179 (MethodHash=4c335586) for method System.Net.WebHeaderEncoding:GetBytes(System.String,int,int,byte[],int) (FullOpts)
 ; ============================================================

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