Added branchless Math.Min calculation

Turnerj · Turnerj · commit f28c3bf7a322 · 2021-11-30T23:06:23.000+10:30
diff --git a/src/Quickenshtein/Internal/AdvOperations.cs b/src/Quickenshtein/Internal/AdvOperations.cs
@@ -0,0 +1,16 @@
+﻿using System;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using System.Text;
+
+namespace Quickenshtein.Internal
+{
+	internal static class AdvOperations
+	{
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		public static int MathMin(int x, int y)
+		{
+			return y + ((x - y) & ((x - y) >> (sizeof(int) * 8 - 1)));
+		}
+	}
+}
diff --git a/src/Quickenshtein/Levenshtein.Common.cs b/src/Quickenshtein/Levenshtein.Common.cs
@@ -35,8 +35,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i
 				lastDeletionCost = previousRowPtr[0];
 				if (sourcePrevChar != targetPtr[0])
 				{
-					localCost = Math.Min(lastInsertionCost, localCost);
-					localCost = Math.Min(lastDeletionCost, localCost);
+					localCost = AdvOperations.MathMin(lastInsertionCost, localCost);
+					localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 					localCost++;
 				}
 				lastInsertionCost = localCost;
@@ -49,8 +49,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i
 				lastDeletionCost = previousRowPtr[0];
 				if (sourcePrevChar != targetPtr[0])
 				{
-					localCost = Math.Min(lastInsertionCost, localCost);
-					localCost = Math.Min(lastDeletionCost, localCost);
+					localCost = AdvOperations.MathMin(lastInsertionCost, localCost);
+					localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 					localCost++;
 				}
 				lastInsertionCost = localCost;
@@ -63,8 +63,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i
 				lastDeletionCost = previousRowPtr[0];
 				if (sourcePrevChar != targetPtr[0])
 				{
-					localCost = Math.Min(lastInsertionCost, localCost);
-					localCost = Math.Min(lastDeletionCost, localCost);
+					localCost = AdvOperations.MathMin(lastInsertionCost, localCost);
+					localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 					localCost++;
 				}
 				lastInsertionCost = localCost;
@@ -77,8 +77,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i
 				lastDeletionCost = previousRowPtr[0];
 				if (sourcePrevChar != targetPtr[0])
 				{
-					localCost = Math.Min(lastInsertionCost, localCost);
-					localCost = Math.Min(lastDeletionCost, localCost);
+					localCost = AdvOperations.MathMin(lastInsertionCost, localCost);
+					localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 					localCost++;
 				}
 				lastInsertionCost = localCost;
@@ -91,8 +91,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i
 				lastDeletionCost = previousRowPtr[0];
 				if (sourcePrevChar != targetPtr[0])
 				{
-					localCost = Math.Min(lastInsertionCost, localCost);
-					localCost = Math.Min(lastDeletionCost, localCost);
+					localCost = AdvOperations.MathMin(lastInsertionCost, localCost);
+					localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 					localCost++;
 				}
 				lastInsertionCost = localCost;
@@ -105,8 +105,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i
 				lastDeletionCost = previousRowPtr[0];
 				if (sourcePrevChar != targetPtr[0])
 				{
-					localCost = Math.Min(lastInsertionCost, localCost);
-					localCost = Math.Min(lastDeletionCost, localCost);
+					localCost = AdvOperations.MathMin(lastInsertionCost, localCost);
+					localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 					localCost++;
 				}
 				lastInsertionCost = localCost;
@@ -119,8 +119,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i
 				lastDeletionCost = previousRowPtr[0];
 				if (sourcePrevChar != targetPtr[0])
 				{
-					localCost = Math.Min(lastInsertionCost, localCost);
-					localCost = Math.Min(lastDeletionCost, localCost);
+					localCost = AdvOperations.MathMin(lastInsertionCost, localCost);
+					localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 					localCost++;
 				}
 				lastInsertionCost = localCost;
@@ -133,8 +133,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i
 				lastDeletionCost = previousRowPtr[0];
 				if (sourcePrevChar != targetPtr[0])
 				{
-					localCost = Math.Min(lastInsertionCost, localCost);
-					localCost = Math.Min(lastDeletionCost, localCost);
+					localCost = AdvOperations.MathMin(lastInsertionCost, localCost);
+					localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 					localCost++;
 				}
 				lastInsertionCost = localCost;
@@ -152,8 +152,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i
 				lastDeletionCost = previousRowPtr[0];
 				if (sourcePrevChar != targetPtr[0])
 				{
-					localCost = Math.Min(lastInsertionCost, localCost);
-					localCost = Math.Min(lastDeletionCost, localCost);
+					localCost = AdvOperations.MathMin(lastInsertionCost, localCost);
+					localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 					localCost++;
 				}
 				lastInsertionCost = localCost;
@@ -166,8 +166,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i
 				lastDeletionCost = previousRowPtr[0];
 				if (sourcePrevChar != targetPtr[0])
 				{
-					localCost = Math.Min(lastInsertionCost, localCost);
-					localCost = Math.Min(lastDeletionCost, localCost);
+					localCost = AdvOperations.MathMin(lastInsertionCost, localCost);
+					localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 					localCost++;
 				}
 				lastInsertionCost = localCost;
@@ -180,8 +180,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i
 				lastDeletionCost = previousRowPtr[0];
 				if (sourcePrevChar != targetPtr[0])
 				{
-					localCost = Math.Min(lastInsertionCost, localCost);
-					localCost = Math.Min(lastDeletionCost, localCost);
+					localCost = AdvOperations.MathMin(lastInsertionCost, localCost);
+					localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 					localCost++;
 				}
 				lastInsertionCost = localCost;
@@ -194,8 +194,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i
 				lastDeletionCost = previousRowPtr[0];
 				if (sourcePrevChar != targetPtr[0])
 				{
-					localCost = Math.Min(lastInsertionCost, localCost);
-					localCost = Math.Min(lastDeletionCost, localCost);
+					localCost = AdvOperations.MathMin(lastInsertionCost, localCost);
+					localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 					localCost++;
 				}
 				lastInsertionCost = localCost;
@@ -213,8 +213,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i
 				lastDeletionCost = previousRowPtr[0];
 				if (sourcePrevChar != targetPtr[0])
 				{
-					localCost = Math.Min(lastInsertionCost, localCost);
-					localCost = Math.Min(lastDeletionCost, localCost);
+					localCost = AdvOperations.MathMin(lastInsertionCost, localCost);
+					localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 					localCost++;
 				}
 				lastInsertionCost = localCost;
@@ -307,35 +307,35 @@ private static unsafe void CalculateColumn_4Rows(ref char* targetPtr, ref int* p
 			var localCost = row1Costs;
 			if (sourceChar1 != targetChar)
 			{
-				localCost = Math.Min(row2Costs, localCost);
-				localCost = Math.Min(lastDeletionCost, localCost);
+				localCost = AdvOperations.MathMin(row2Costs, localCost);
+				localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 				localCost++;
 			}
 			row1Costs = lastDeletionCost;
 			lastDeletionCost = localCost;
 			localCost = row2Costs;
 			if (sourceChar2 != targetChar)
 			{
-				localCost = Math.Min(row3Costs, localCost);
-				localCost = Math.Min(lastDeletionCost, localCost);
+				localCost = AdvOperations.MathMin(row3Costs, localCost);
+				localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 				localCost++;
 			}
 			row2Costs = lastDeletionCost;
 			lastDeletionCost = localCost;
 			localCost = row3Costs;
 			if (sourceChar3 != targetChar)
 			{
-				localCost = Math.Min(row4Costs, localCost);
-				localCost = Math.Min(lastDeletionCost, localCost);
+				localCost = AdvOperations.MathMin(row4Costs, localCost);
+				localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 				localCost++;
 			}
 			row3Costs = lastDeletionCost;
 			lastDeletionCost = localCost;
 			localCost = row4Costs;
 			if (sourceChar4 != targetChar)
 			{
-				localCost = Math.Min(row5Costs, localCost);
-				localCost = Math.Min(lastDeletionCost, localCost);
+				localCost = AdvOperations.MathMin(row5Costs, localCost);
+				localCost = AdvOperations.MathMin(lastDeletionCost, localCost);
 				localCost++;
 			}
 			row4Costs = lastDeletionCost;

Original file line number	Diff line number	Diff line change
`@@ -35,8 +35,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i`
`35`	`35`	`lastDeletionCost = previousRowPtr[0];`
`36`	`36`	`if (sourcePrevChar != targetPtr[0])`
`37`	`37`	`{`
`38`		`- localCost = Math.Min(lastInsertionCost, localCost);`
`39`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`38`	`+ localCost = AdvOperations.MathMin(lastInsertionCost, localCost);`
	`39`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`40`	`40`	`localCost++;`
`41`	`41`	`}`
`42`	`42`	`lastInsertionCost = localCost;`
`@@ -49,8 +49,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i`
`49`	`49`	`lastDeletionCost = previousRowPtr[0];`
`50`	`50`	`if (sourcePrevChar != targetPtr[0])`
`51`	`51`	`{`
`52`		`- localCost = Math.Min(lastInsertionCost, localCost);`
`53`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`52`	`+ localCost = AdvOperations.MathMin(lastInsertionCost, localCost);`
	`53`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`54`	`54`	`localCost++;`
`55`	`55`	`}`
`56`	`56`	`lastInsertionCost = localCost;`
`@@ -63,8 +63,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i`
`63`	`63`	`lastDeletionCost = previousRowPtr[0];`
`64`	`64`	`if (sourcePrevChar != targetPtr[0])`
`65`	`65`	`{`
`66`		`- localCost = Math.Min(lastInsertionCost, localCost);`
`67`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`66`	`+ localCost = AdvOperations.MathMin(lastInsertionCost, localCost);`
	`67`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`68`	`68`	`localCost++;`
`69`	`69`	`}`
`70`	`70`	`lastInsertionCost = localCost;`
`@@ -77,8 +77,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i`
`77`	`77`	`lastDeletionCost = previousRowPtr[0];`
`78`	`78`	`if (sourcePrevChar != targetPtr[0])`
`79`	`79`	`{`
`80`		`- localCost = Math.Min(lastInsertionCost, localCost);`
`81`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`80`	`+ localCost = AdvOperations.MathMin(lastInsertionCost, localCost);`
	`81`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`82`	`82`	`localCost++;`
`83`	`83`	`}`
`84`	`84`	`lastInsertionCost = localCost;`
`@@ -91,8 +91,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i`
`91`	`91`	`lastDeletionCost = previousRowPtr[0];`
`92`	`92`	`if (sourcePrevChar != targetPtr[0])`
`93`	`93`	`{`
`94`		`- localCost = Math.Min(lastInsertionCost, localCost);`
`95`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`94`	`+ localCost = AdvOperations.MathMin(lastInsertionCost, localCost);`
	`95`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`96`	`96`	`localCost++;`
`97`	`97`	`}`
`98`	`98`	`lastInsertionCost = localCost;`
`@@ -105,8 +105,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i`
`105`	`105`	`lastDeletionCost = previousRowPtr[0];`
`106`	`106`	`if (sourcePrevChar != targetPtr[0])`
`107`	`107`	`{`
`108`		`- localCost = Math.Min(lastInsertionCost, localCost);`
`109`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`108`	`+ localCost = AdvOperations.MathMin(lastInsertionCost, localCost);`
	`109`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`110`	`110`	`localCost++;`
`111`	`111`	`}`
`112`	`112`	`lastInsertionCost = localCost;`
`@@ -119,8 +119,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i`
`119`	`119`	`lastDeletionCost = previousRowPtr[0];`
`120`	`120`	`if (sourcePrevChar != targetPtr[0])`
`121`	`121`	`{`
`122`		`- localCost = Math.Min(lastInsertionCost, localCost);`
`123`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`122`	`+ localCost = AdvOperations.MathMin(lastInsertionCost, localCost);`
	`123`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`124`	`124`	`localCost++;`
`125`	`125`	`}`
`126`	`126`	`lastInsertionCost = localCost;`
`@@ -133,8 +133,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i`
`133`	`133`	`lastDeletionCost = previousRowPtr[0];`
`134`	`134`	`if (sourcePrevChar != targetPtr[0])`
`135`	`135`	`{`
`136`		`- localCost = Math.Min(lastInsertionCost, localCost);`
`137`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`136`	`+ localCost = AdvOperations.MathMin(lastInsertionCost, localCost);`
	`137`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`138`	`138`	`localCost++;`
`139`	`139`	`}`
`140`	`140`	`lastInsertionCost = localCost;`
`@@ -152,8 +152,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i`
`152`	`152`	`lastDeletionCost = previousRowPtr[0];`
`153`	`153`	`if (sourcePrevChar != targetPtr[0])`
`154`	`154`	`{`
`155`		`- localCost = Math.Min(lastInsertionCost, localCost);`
`156`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`155`	`+ localCost = AdvOperations.MathMin(lastInsertionCost, localCost);`
	`156`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`157`	`157`	`localCost++;`
`158`	`158`	`}`
`159`	`159`	`lastInsertionCost = localCost;`
`@@ -166,8 +166,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i`
`166`	`166`	`lastDeletionCost = previousRowPtr[0];`
`167`	`167`	`if (sourcePrevChar != targetPtr[0])`
`168`	`168`	`{`
`169`		`- localCost = Math.Min(lastInsertionCost, localCost);`
`170`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`169`	`+ localCost = AdvOperations.MathMin(lastInsertionCost, localCost);`
	`170`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`171`	`171`	`localCost++;`
`172`	`172`	`}`
`173`	`173`	`lastInsertionCost = localCost;`
`@@ -180,8 +180,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i`
`180`	`180`	`lastDeletionCost = previousRowPtr[0];`
`181`	`181`	`if (sourcePrevChar != targetPtr[0])`
`182`	`182`	`{`
`183`		`- localCost = Math.Min(lastInsertionCost, localCost);`
`184`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`183`	`+ localCost = AdvOperations.MathMin(lastInsertionCost, localCost);`
	`184`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`185`	`185`	`localCost++;`
`186`	`186`	`}`
`187`	`187`	`lastInsertionCost = localCost;`
`@@ -194,8 +194,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i`
`194`	`194`	`lastDeletionCost = previousRowPtr[0];`
`195`	`195`	`if (sourcePrevChar != targetPtr[0])`
`196`	`196`	`{`
`197`		`- localCost = Math.Min(lastInsertionCost, localCost);`
`198`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`197`	`+ localCost = AdvOperations.MathMin(lastInsertionCost, localCost);`
	`198`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`199`	`199`	`localCost++;`
`200`	`200`	`}`
`201`	`201`	`lastInsertionCost = localCost;`
`@@ -213,8 +213,8 @@ internal static unsafe void CalculateRow(int* previousRowPtr, char* targetPtr, i`
`213`	`213`	`lastDeletionCost = previousRowPtr[0];`
`214`	`214`	`if (sourcePrevChar != targetPtr[0])`
`215`	`215`	`{`
`216`		`- localCost = Math.Min(lastInsertionCost, localCost);`
`217`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`216`	`+ localCost = AdvOperations.MathMin(lastInsertionCost, localCost);`
	`217`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`218`	`218`	`localCost++;`
`219`	`219`	`}`
`220`	`220`	`lastInsertionCost = localCost;`
`@@ -307,35 +307,35 @@ private static unsafe void CalculateColumn_4Rows(ref char* targetPtr, ref int* p`
`307`	`307`	`var localCost = row1Costs;`
`308`	`308`	`if (sourceChar1 != targetChar)`
`309`	`309`	`{`
`310`		`- localCost = Math.Min(row2Costs, localCost);`
`311`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`310`	`+ localCost = AdvOperations.MathMin(row2Costs, localCost);`
	`311`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`312`	`312`	`localCost++;`
`313`	`313`	`}`
`314`	`314`	`row1Costs = lastDeletionCost;`
`315`	`315`	`lastDeletionCost = localCost;`
`316`	`316`	`localCost = row2Costs;`
`317`	`317`	`if (sourceChar2 != targetChar)`
`318`	`318`	`{`
`319`		`- localCost = Math.Min(row3Costs, localCost);`
`320`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`319`	`+ localCost = AdvOperations.MathMin(row3Costs, localCost);`
	`320`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`321`	`321`	`localCost++;`
`322`	`322`	`}`
`323`	`323`	`row2Costs = lastDeletionCost;`
`324`	`324`	`lastDeletionCost = localCost;`
`325`	`325`	`localCost = row3Costs;`
`326`	`326`	`if (sourceChar3 != targetChar)`
`327`	`327`	`{`
`328`		`- localCost = Math.Min(row4Costs, localCost);`
`329`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`328`	`+ localCost = AdvOperations.MathMin(row4Costs, localCost);`
	`329`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`330`	`330`	`localCost++;`
`331`	`331`	`}`
`332`	`332`	`row3Costs = lastDeletionCost;`
`333`	`333`	`lastDeletionCost = localCost;`
`334`	`334`	`localCost = row4Costs;`
`335`	`335`	`if (sourceChar4 != targetChar)`
`336`	`336`	`{`
`337`		`- localCost = Math.Min(row5Costs, localCost);`
`338`		`- localCost = Math.Min(lastDeletionCost, localCost);`
	`337`	`+ localCost = AdvOperations.MathMin(row5Costs, localCost);`
	`338`	`+ localCost = AdvOperations.MathMin(lastDeletionCost, localCost);`
`339`	`339`	`localCost++;`
`340`	`340`	`}`
`341`	`341`	`row4Costs = lastDeletionCost;`