[JitDiff X64] [hez2010] JIT: Constant fold SequenceEqual with the help of VN

[MihuBot]

Job completed in 15 minutes 58 seconds (remote runner delay: 1 minute 18 seconds).
dotnet/runtime#121985

Main commit: dotnet/runtime@cd5f273
PR commit: hez2010/runtime@935c2d4

Diffs

Found 85 files with textual diffs.

Summary of Code Size diffs:
(Lower is better)

Total bytes of base: 45258114
Total bytes of diff: 45258053
Total bytes of delta: -61 (-0.00 % of base)
Total relative delta: -0.11
    diff is an improvement.
    relative diff is an improvement.


Top file improvements (bytes):
         -40 : System.Reflection.Metadata.dasm (-0.01 % of base)
         -21 : System.Data.Common.dasm (-0.00 % of base)

2 total files with Code Size differences (2 improved, 0 regressed), 258 unchanged.

Top method improvements (bytes):
         -40 (-0.66 % of base) : System.Reflection.Metadata.dasm - System.Reflection.Metadata.Ecma335.MetadataBuilder:.ctor(int,int,int,int):this (FullOpts)
         -21 (-10.45 % of base) : System.Data.Common.dasm - System.Data.Common.DbConnectionStringBuilderDescriptor:SetValue(System.Object,System.Object):this (FullOpts)

Top method improvements (percentages):
         -21 (-10.45 % of base) : System.Data.Common.dasm - System.Data.Common.DbConnectionStringBuilderDescriptor:SetValue(System.Object,System.Object):this (FullOpts)
         -40 (-0.66 % of base) : System.Reflection.Metadata.dasm - System.Reflection.Metadata.Ecma335.MetadataBuilder:.ctor(int,int,int,int):this (FullOpts)

2 total methods with Code Size differences (2 improved, 0 regressed), 283301 unchanged.

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

Artifacts:

• jit-diffs-main.zip (154 MB)
• jit-diffs-pr.zip (154 MB)
• diff-frameworks.txt (1 KB)
• ShortDiffsImprovements.md (6 KB)
• LongDiffsImprovements.md (96 KB)

[MihuBot]

Top method improvements

-21 (-10.45 % of base) - System.Data.Common.DbConnectionStringBuilderDescriptor:SetValue(System.Object,System.Object):this

 ; Assembly listing for method System.Data.Common.DbConnectionStringBuilderDescriptor:SetValue(System.Object,System.Object):this (FullOpts)
 ; Emitting BLENDED_CODE for generic X64 + VEX + EVEX on Unix
 ; FullOpts code
 ; optimized code
 ; rbp based frame
 ; partially interruptible
 ; No PGO data
 ; 0 inlinees with PGO data; 6 single block inlinees; 1 inlinees without PGO data
 ; Final local variable assignments
 ;
 ;  V00 this         [V00,T01] (  5,  3.50)     ref  ->  r15         this class-hnd single-def <System.Data.Common.DbConnectionStringBuilderDescriptor>
 ;  V01 arg1         [V01,T02] (  3,  3   )     ref  ->  rsi         class-hnd single-def <System.Object>
-;  V02 arg2         [V02,T00] (  9,  5.25)     ref  ->  rbx         class-hnd <System.Object>
+;  V02 arg2         [V02,T00] (  8,  4.75)     ref  ->  rbx         class-hnd <System.Object>
 ;  V03 loc0         [V03,T03] (  5,  3.50)     ref  ->  r14         class-hnd single-def <System.Data.Common.DbConnectionStringBuilder>
 ;# V04 OutArgs      [V04    ] (  1,  1   )  struct ( 0) [rsp+0x00]  do-not-enreg[XS] addr-exposed "OutgoingArgSpace" <Empty>
 ;* V05 tmp1         [V05    ] (  0,  0   )     ref  ->  zero-ref    class-hnd exact "impAppendStmt" <System.RuntimeType>
-;  V06 tmp2         [V06,T07] (  2,  1   )   ubyte  ->  rax         "Inline return value spill temp"
+;  V06 tmp2         [V06,T06] (  2,  1   )   ubyte  ->  rdi         "Inline return value spill temp"
 ;* V07 tmp3         [V07    ] (  0,  0   )     ref  ->  zero-ref    class-hnd "spilling qmarkNull" <System.String>
 ;* V08 tmp4         [V08,T08] (  0,  0   )     ref  ->  zero-ref    class-hnd exact "Inline stloc first use temp" <System.String>
-;  V09 tmp5         [V09,T04] (  2,  2   )   byref  ->  rdi         single-def "impAppendStmt"
-;  V10 tmp6         [V10,T05] (  2,  2   )     ref  ->  rsi         single-def "argument with side effect"
-;  V11 cse0         [V11,T06] (  3,  1.50)     ref  ->  rdi         "CSE #01: moderate"
+;* V09 tmp5         [V09,T07] (  0,  0   )   byref  ->  zero-ref    single-def "impAppendStmt"
+;  V10 tmp6         [V10,T04] (  2,  2   )     ref  ->  rsi         single-def "argument with side effect"
+;  V11 cse0         [V11,T05] (  2,  1   )     ref  ->  rdi         "CSE #01: moderate"
 ;
 ; Lcl frame size = 8
 
 G_M18713_IG01:
        push     rbp
        push     r15
        push     r14
        push     rbx
        push     rax
        lea      rbp, [rsp+0x20]
        mov      r15, rdi
        mov      rbx, rdx
 						;; size=18 bbWeight=1 PerfScore 6.00
 G_M18713_IG02:
        mov      rdi, 0xD1FFAB1E      ; System.Data.Common.DbConnectionStringBuilder
        mov      rax, 0xD1FFAB1E      ; code for CORINFO_HELP_ISINSTANCEOFCLASS
        call     [rax]CORINFO_HELP_ISINSTANCEOFCLASS
        mov      r14, rax
        test     r14, r14
-       je       G_M18713_IG08
-						;; size=34 bbWeight=1 PerfScore 5.00
+       je       SHORT G_M18713_IG08
+						;; size=30 bbWeight=1 PerfScore 5.00
 G_M18713_IG03:
-       mov      rsi, 0xD1FFAB1E      ; 'System.String'
-       cmp      gword ptr [r15+0x90], rsi
+       mov      rdi, 0xD1FFAB1E      ; 'System.String'
+       cmp      gword ptr [r15+0x90], rdi
        jne      SHORT G_M18713_IG07
        mov      rdi, 0xD1FFAB1E      ; ''
        cmp      rbx, rdi
        je       SHORT G_M18713_IG06
        test     rbx, rbx
        je       SHORT G_M18713_IG07
 						;; size=39 bbWeight=0.50 PerfScore 3.50
 G_M18713_IG04:
-       mov      rsi, 0xD1FFAB1E      ; System.String
-       cmp      qword ptr [rbx], rsi
+       mov      rdi, 0xD1FFAB1E      ; System.String
+       cmp      qword ptr [rbx], rdi
        jne      SHORT G_M18713_IG07
 						;; size=15 bbWeight=0.25 PerfScore 1.06
 G_M18713_IG05:
        cmp      dword ptr [rbx+0x08], 0
        jne      SHORT G_M18713_IG07
-       add      rdi, 12
-       lea      rsi, bword ptr [rbx+0x0C]
-       xor      edx, edx
-       mov      rax, 0xD1FFAB1E      ; code for System.SpanHelpers:SequenceEqual(byref,byref,nuint):bool
-       call     [rax]System.SpanHelpers:SequenceEqual(byref,byref,nuint):bool
-       test     eax, eax
+       mov      edi, 1
+       test     edi, edi
        je       SHORT G_M18713_IG07
-						;; size=32 bbWeight=0.50 PerfScore 4.75
+						;; size=15 bbWeight=0.50 PerfScore 2.75
 G_M18713_IG06:
        xor      rbx, rbx
 						;; size=2 bbWeight=0.50 PerfScore 0.12
 G_M18713_IG07:
        mov      rdi, r15
        mov      rax, 0xD1FFAB1E      ; code for System.ComponentModel.MemberDescriptor:get_DisplayName():System.String:this
        call     [rax]System.ComponentModel.MemberDescriptor:get_DisplayName():System.String:this
        mov      rsi, rax
        mov      rdi, r14
        mov      rdx, rbx
        mov      rax, qword ptr [r14]
        mov      rax, qword ptr [rax+0x40]
        call     [rax+0x38]System.Data.Common.DbConnectionStringBuilder:set_Item(System.String,System.Object):this
        cmp      byte  ptr [r15+0x84], 0
        je       SHORT G_M18713_IG08
        xor      rax, rax
        mov      gword ptr [r14+0x18], rax
 						;; size=50 bbWeight=0.50 PerfScore 8.25
 G_M18713_IG08:
        add      rsp, 8
        pop      rbx
        pop      r14
        pop      r15
        pop      rbp
        ret      
 						;; size=11 bbWeight=1 PerfScore 3.25
 
-; Total bytes of code 201, prolog size 12, PerfScore 31.94, instruction count 54, allocated bytes for code 201 (MethodHash=a7d0b6e6) for method System.Data.Common.DbConnectionStringBuilderDescriptor:SetValue(System.Object,System.Object):this (FullOpts)
+; Total bytes of code 180, prolog size 12, PerfScore 29.94, instruction count 50, allocated bytes for code 180 (MethodHash=a7d0b6e6) for method System.Data.Common.DbConnectionStringBuilderDescriptor:SetValue(System.Object,System.Object):this (FullOpts)
 ; ============================================================

Note: some changes were skipped as they were too large to fit into a comment.

Larger list of diffs: https://gist.github.com/MihuBot/6143ba50fa84f6f0022a11d6e3334994

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