NET7 Int128, UInt128 - bugs in ToString

[c-ohle]

Description

Wrong ToString results for Int128, UInt128

Self explaining, in UInt128ToDecStr(UInt128) since CountDigits ignores the highword.
CountDigits and its variants should be rewritten as it is the most stupid and slowest implementation I ever saw.

Reproduction Steps

var x = Int128.MaxValue / Int64.MaxValue; var ss = x.ToString(); // => "2"
var y = UInt128.MaxValue / UInt64.MaxValue; var sy = y.ToString(); // => "1"

Expected behavior

var x = Int128.MaxValue / Int64.MaxValue; var ss = x.ToString(); // => "18446744073709551618"
var y = UInt128.MaxValue / UInt64.MaxValue; var sy = y.ToString(); // => "18446744073709551617"

Actual behavior

var x = Int128.MaxValue / Int64.MaxValue; var ss = x.ToString(); // => "2"
var y = UInt128.MaxValue / UInt64.MaxValue; var sy = y.ToString(); // => "1"

Regression?

No response

Known Workarounds

No response

Configuration

No response

Other information

No response

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Issue Details

---

Description

Wrong ToString results for Int128, UInt128

Self explaining, in UInt128ToDecStr(UInt128) since CountDigits ignores the highword.
CountDigits and its variants should be rewritten as it is the most stupid and slowest implementation I ever saw.

Reproduction Steps

var x = Int128.MaxValue / Int64.MaxValue; var ss = x.ToString(); // => "2"
var y = UInt128.MaxValue / UInt64.MaxValue; var sy = y.ToString(); // => "1"

Expected behavior

var x = Int128.MaxValue / Int64.MaxValue; var ss = x.ToString(); // => "18446744073709551618"
var y = UInt128.MaxValue / UInt64.MaxValue; var sy = y.ToString(); // => "18446744073709551617"

Actual behavior

var x = Int128.MaxValue / Int64.MaxValue; var ss = x.ToString(); // => "2"
var y = UInt128.MaxValue / UInt64.MaxValue; var sy = y.ToString(); // => "1"

Regression?

No response

Known Workarounds

No response

Configuration

No response

Other information

No response

Author:	c-ohle
Assignees:	-
Labels:	area-System.Numerics, untriaged
Milestone:	-

[Wraith2]

CountDigits and its variants should be rewritten as it is the most stupid and slowest implementation I ever saw.

This is inflamatory and unhelpful. Please learn to communicate more effectively with others.

[c-ohle]

@Wraith2 ok, can I help you?

[EgorBo]

I guess it's fixed with #74501