RyuJIT should optimize "X & mask" to "(type)X" #36952
Description
Inspired by #36920 (comment), e.g.
ulong Test(ulong x)
{
return x & 0xFFFFFFFF; // should be optimized to "(uint)x"
}Expected codegen:
mov eax, edx
retActual codegen:
mov eax, 0xffffffff
and rax, rdx
retQuick prototype: EgorBo@dcf81a5
Jit-diff:
Found 49 files with textual diffs.
Summary of Code Size diffs:
(Lower is better)
Total bytes of diff: -17090 (-0.03% of base)
diff is an improvement.
Top file improvements (bytes):
-15064 : System.Data.Common.dasm (-1.00% of base)
-411 : Microsoft.CodeAnalysis.CSharp.dasm (-0.01% of base)
-228 : System.Private.CoreLib.dasm (-0.00% of base)
-149 : Microsoft.Diagnostics.Tracing.TraceEvent.dasm (-0.00% of base)
-129 : System.Security.Cryptography.X509Certificates.dasm (-0.07% of base)
-124 : System.Security.Cryptography.Pkcs.dasm (-0.02% of base)
-121 : System.Private.Uri.dasm (-0.13% of base)
-116 : Microsoft.CodeAnalysis.dasm (-0.01% of base)
-108 : System.Runtime.Caching.dasm (-0.18% of base)
-86 : Microsoft.VisualBasic.Core.dasm (-0.02% of base)
-71 : System.Net.Primitives.dasm (-0.10% of base)
-41 : Microsoft.CodeAnalysis.VisualBasic.dasm (-0.00% of base)
-40 : System.Diagnostics.FileVersionInfo.dasm (-1.01% of base)
-34 : System.Private.Xml.dasm (-0.00% of base)
-28 : System.Net.Sockets.dasm (-0.01% of base)
-23 : System.DirectoryServices.dasm (-0.01% of base)
-23 : System.Net.NetworkInformation.dasm (-0.06% of base)
-20 : System.Net.Http.WinHttpHandler.dasm (-0.02% of base)
-18 : System.Diagnostics.EventLog.dasm (-0.02% of base)
-18 : System.Drawing.Primitives.dasm (-0.05% of base)
Full log.
Most of the jit-diff comes from System.Data.RBTree1` and PMI but still looks useful IMO.
category:cq
theme:basic-cq
skill-level:intermediate
cost:medium
impact:small