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.NET is a cross-platform runtime for cloud, mobile, desktop, and IoT apps.
https://docs.microsoft.com/dotnet/core/
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ARM64: suboptimal codegen for Vector64.Create(1) #101661

Open EgorBo opened 2 weeks ago

EgorBo commented 2 weeks ago 
Vector64<int> Test() => Vector64.Create(1);

Proposed codegen diff:

; Method Prog:Test():System.Runtime.Intrinsics.Vector64`1[int]:this (FullOpts)
G_M63775_IG01:
            stp     fp, lr, [sp, #-0x10]!
            mov     fp, sp
G_M63775_IG02:
-           ldr     d0, [@RWD00]
+           movi    v0.2s, #1
G_M63775_IG03:
            ldp     fp, lr, [sp], #0x10
            ret     lr
-RWD00      dq  0000000100000001h
; Total bytes of code: 20

PS: actually, not just Vector64.Create(1), but any imm-able constant for movi

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