JIT: AssertProp propagates const vector back to loop body #70355

Closed
#70378
Closed
JIT: AssertProp propagates const vector back to loop body#70355
#70378
Assignees
EgorBo
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area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI
Milestone
7.0.0

Description

@EgorBo
EgorBo
opened on Jun 7, 2022

Minimal repro from #70336 (comment)

staticintTest(){varcns=Vector128.Create(1,2,3,4);inti=0;do{i=(cns+Vector128.Create(i)).ToScalar();}while(i<100);returni;}

Despite the fact I declared the constant vector outside of the loop it ends up inside leading to a memory load each iteration:

x64:

; Method C:Test():intG_M43325_IG01:vzeroupperG_M43325_IG02:xoreax,eaxalign[11 bytes for IG03]G_M43325_IG03: vmovd xmm0,eaxvpbroadcastdxmm0,xmm0vpadddxmm0,xmm0, xmmword ptr [reloc @RWD00] vmovd eax,xmm0cmpeax,100jl SHORT G_M43325_IG03G_M43325_IG04:retRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 43

Arm64:

; Method C:Test():intG_M43325_IG01: stp fp, lr,[sp,#-16]!mov fp,spG_M43325_IG02:mov w0, wzrG_M43325_IG03: dup v16.4s, w0 ldr q17,[@RWD00]add v16.4s, v17.4s, v16.4s smov x0, v16.s[0]cmp w0, #100 blt G_M43325_IG03G_M43325_IG04: ldp fp, lr,[sp],#16ret lrRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 44

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    Skip to content
    JIT: AssertProp propagates const vector back to loop body #70355
    Closed
    #70378
    Closed
    JIT: AssertProp propagates const vector back to loop body#70355
    #70378
    Assignees
    EgorBo
    Labels
    area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI
    Milestone
    7.0.0
    Description
    @EgorBo
    EgorBo
    opened on Jun 7, 2022
    Minimal repro from #70336 (comment)
    staticintTest(){varcns=Vector128.Create(1,2,3,4);inti=0;do{i=(cns+Vector128.Create(i)).ToScalar();}while(i<100);returni;}
    Despite the fact I declared the constant vector outside of the loop it ends up inside leading to a memory load each iteration:
    x64:
    ; Method C:Test():intG_M43325_IG01:vzeroupperG_M43325_IG02:xoreax,eaxalign[11 bytes for IG03]G_M43325_IG03: vmovd xmm0,eaxvpbroadcastdxmm0,xmm0vpadddxmm0,xmm0, xmmword ptr [reloc @RWD00] vmovd eax,xmm0cmpeax,100jl SHORT G_M43325_IG03G_M43325_IG04:retRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 43
    Arm64:
    ; Method C:Test():intG_M43325_IG01: stp fp, lr,[sp,#-16]!mov fp,spG_M43325_IG02:mov w0, wzrG_M43325_IG03: dup v16.4s, w0 ldr q17,[@RWD00]add v16.4s, v17.4s, v16.4s smov x0, v16.s[0]cmp w0, #100 blt G_M43325_IG03G_M43325_IG04: ldp fp, lr,[sp],#16ret lrRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 44
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var __m = "*";
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      Skip to content
      JIT: AssertProp propagates const vector back to loop body #70355
      Closed
      #70378
      Closed
      JIT: AssertProp propagates const vector back to loop body#70355
      #70378
      Assignees
      EgorBo
      Labels
      area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI
      Milestone
      7.0.0
      Description
      @EgorBo
      EgorBo
      opened on Jun 7, 2022
      Minimal repro from #70336 (comment)
      staticintTest(){varcns=Vector128.Create(1,2,3,4);inti=0;do{i=(cns+Vector128.Create(i)).ToScalar();}while(i<100);returni;}
      Despite the fact I declared the constant vector outside of the loop it ends up inside leading to a memory load each iteration:
      x64:
      ; Method C:Test():intG_M43325_IG01:vzeroupperG_M43325_IG02:xoreax,eaxalign[11 bytes for IG03]G_M43325_IG03: vmovd xmm0,eaxvpbroadcastdxmm0,xmm0vpadddxmm0,xmm0, xmmword ptr [reloc @RWD00] vmovd eax,xmm0cmpeax,100jl SHORT G_M43325_IG03G_M43325_IG04:retRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 43
      Arm64:
      ; Method C:Test():intG_M43325_IG01: stp fp, lr,[sp,#-16]!mov fp,spG_M43325_IG02:mov w0, wzrG_M43325_IG03: dup v16.4s, w0 ldr q17,[@RWD00]add v16.4s, v17.4s, v16.4s smov x0, v16.s[0]cmp w0, #100 blt G_M43325_IG03G_M43325_IG04: ldp fp, lr,[sp],#16ret lrRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 44
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(function(){
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var __m = "*";
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        Skip to content
        JIT: AssertProp propagates const vector back to loop body #70355
        Closed
        #70378
        Closed
        JIT: AssertProp propagates const vector back to loop body#70355
        #70378
        Assignees
        EgorBo
        Labels
        area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI
        Milestone
        7.0.0
        Description
        @EgorBo
        EgorBo
        opened on Jun 7, 2022
        Minimal repro from #70336 (comment)
        staticintTest(){varcns=Vector128.Create(1,2,3,4);inti=0;do{i=(cns+Vector128.Create(i)).ToScalar();}while(i<100);returni;}
        Despite the fact I declared the constant vector outside of the loop it ends up inside leading to a memory load each iteration:
        x64:
        ; Method C:Test():intG_M43325_IG01:vzeroupperG_M43325_IG02:xoreax,eaxalign[11 bytes for IG03]G_M43325_IG03: vmovd xmm0,eaxvpbroadcastdxmm0,xmm0vpadddxmm0,xmm0, xmmword ptr [reloc @RWD00] vmovd eax,xmm0cmpeax,100jl SHORT G_M43325_IG03G_M43325_IG04:retRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 43
        Arm64:
        ; Method C:Test():intG_M43325_IG01: stp fp, lr,[sp,#-16]!mov fp,spG_M43325_IG02:mov w0, wzrG_M43325_IG03: dup v16.4s, w0 ldr q17,[@RWD00]add v16.4s, v17.4s, v16.4s smov x0, v16.s[0]cmp w0, #100 blt G_M43325_IG03G_M43325_IG04: ldp fp, lr,[sp],#16ret lrRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 44
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(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

          Skip to content
          JIT: AssertProp propagates const vector back to loop body #70355
          Closed
          #70378
          Closed
          JIT: AssertProp propagates const vector back to loop body#70355
          #70378
          Assignees
          EgorBo
          Labels
          area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI
          Milestone
          7.0.0
          Description
          @EgorBo
          EgorBo
          opened on Jun 7, 2022
          Minimal repro from #70336 (comment)
          staticintTest(){varcns=Vector128.Create(1,2,3,4);inti=0;do{i=(cns+Vector128.Create(i)).ToScalar();}while(i<100);returni;}
          Despite the fact I declared the constant vector outside of the loop it ends up inside leading to a memory load each iteration:
          x64:
          ; Method C:Test():intG_M43325_IG01:vzeroupperG_M43325_IG02:xoreax,eaxalign[11 bytes for IG03]G_M43325_IG03: vmovd xmm0,eaxvpbroadcastdxmm0,xmm0vpadddxmm0,xmm0, xmmword ptr [reloc @RWD00] vmovd eax,xmm0cmpeax,100jl SHORT G_M43325_IG03G_M43325_IG04:retRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 43
          Arm64:
          ; Method C:Test():intG_M43325_IG01: stp fp, lr,[sp,#-16]!mov fp,spG_M43325_IG02:mov w0, wzrG_M43325_IG03: dup v16.4s, w0 ldr q17,[@RWD00]add v16.4s, v17.4s, v16.4s smov x0, v16.s[0]cmp w0, #100 blt G_M43325_IG03G_M43325_IG04: ldp fp, lr,[sp],#16ret lrRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 44
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try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

            Skip to content
            JIT: AssertProp propagates const vector back to loop body #70355
            Closed
            #70378
            Closed
            JIT: AssertProp propagates const vector back to loop body#70355
            #70378
            Assignees
            EgorBo
            Labels
            area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI
            Milestone
            7.0.0
            Description
            @EgorBo
            EgorBo
            opened on Jun 7, 2022
            Minimal repro from #70336 (comment)
            staticintTest(){varcns=Vector128.Create(1,2,3,4);inti=0;do{i=(cns+Vector128.Create(i)).ToScalar();}while(i<100);returni;}
            Despite the fact I declared the constant vector outside of the loop it ends up inside leading to a memory load each iteration:
            x64:
            ; Method C:Test():intG_M43325_IG01:vzeroupperG_M43325_IG02:xoreax,eaxalign[11 bytes for IG03]G_M43325_IG03: vmovd xmm0,eaxvpbroadcastdxmm0,xmm0vpadddxmm0,xmm0, xmmword ptr [reloc @RWD00] vmovd eax,xmm0cmpeax,100jl SHORT G_M43325_IG03G_M43325_IG04:retRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 43
            Arm64:
            ; Method C:Test():intG_M43325_IG01: stp fp, lr,[sp,#-16]!mov fp,spG_M43325_IG02:mov w0, wzrG_M43325_IG03: dup v16.4s, w0 ldr q17,[@RWD00]add v16.4s, v17.4s, v16.4s smov x0, v16.s[0]cmp w0, #100 blt G_M43325_IG03G_M43325_IG04: ldp fp, lr,[sp],#16ret lrRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 44
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(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

              Skip to content
              JIT: AssertProp propagates const vector back to loop body #70355
              Closed
              #70378
              Closed
              JIT: AssertProp propagates const vector back to loop body#70355
              #70378
              Assignees
              EgorBo
              Labels
              area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI
              Milestone
              7.0.0
              Description
              @EgorBo
              EgorBo
              opened on Jun 7, 2022
              Minimal repro from #70336 (comment)
              staticintTest(){varcns=Vector128.Create(1,2,3,4);inti=0;do{i=(cns+Vector128.Create(i)).ToScalar();}while(i<100);returni;}
              Despite the fact I declared the constant vector outside of the loop it ends up inside leading to a memory load each iteration:
              x64:
              ; Method C:Test():intG_M43325_IG01:vzeroupperG_M43325_IG02:xoreax,eaxalign[11 bytes for IG03]G_M43325_IG03: vmovd xmm0,eaxvpbroadcastdxmm0,xmm0vpadddxmm0,xmm0, xmmword ptr [reloc @RWD00] vmovd eax,xmm0cmpeax,100jl SHORT G_M43325_IG03G_M43325_IG04:retRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 43
              Arm64:
              ; Method C:Test():intG_M43325_IG01: stp fp, lr,[sp,#-16]!mov fp,spG_M43325_IG02:mov w0, wzrG_M43325_IG03: dup v16.4s, w0 ldr q17,[@RWD00]add v16.4s, v17.4s, v16.4s smov x0, v16.s[0]cmp w0, #100 blt G_M43325_IG03G_M43325_IG04: ldp fp, lr,[sp],#16ret lrRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 44
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                JIT: AssertProp propagates const vector back to loop body #70355
                Closed
                #70378
                Closed
                JIT: AssertProp propagates const vector back to loop body#70355
                #70378
                Assignees
                EgorBo
                Labels
                area-CodeGen-coreclrCLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI
                Milestone
                7.0.0
                Description
                @EgorBo
                EgorBo
                opened on Jun 7, 2022
                Minimal repro from #70336 (comment)
                staticintTest(){varcns=Vector128.Create(1,2,3,4);inti=0;do{i=(cns+Vector128.Create(i)).ToScalar();}while(i<100);returni;}
                Despite the fact I declared the constant vector outside of the loop it ends up inside leading to a memory load each iteration:
                x64:
                ; Method C:Test():intG_M43325_IG01:vzeroupperG_M43325_IG02:xoreax,eaxalign[11 bytes for IG03]G_M43325_IG03: vmovd xmm0,eaxvpbroadcastdxmm0,xmm0vpadddxmm0,xmm0, xmmword ptr [reloc @RWD00] vmovd eax,xmm0cmpeax,100jl SHORT G_M43325_IG03G_M43325_IG04:retRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 43
                Arm64:
                ; Method C:Test():intG_M43325_IG01: stp fp, lr,[sp,#-16]!mov fp,spG_M43325_IG02:mov w0, wzrG_M43325_IG03: dup v16.4s, w0 ldr q17,[@RWD00]add v16.4s, v17.4s, v16.4s smov x0, v16.s[0]cmp w0, #100 blt G_M43325_IG03G_M43325_IG04: ldp fp, lr,[sp],#16ret lrRWD00 dq	0000000200000001h,0000000400000003h; Total bytes of code: 44
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