improved HugeInt addition and subtraction performance, and...

- updated the benchmarks in README to reflect the improvements

Author: RandomHashTags

README.md

@@ -35,15 +35,15 @@ The tables below display the nanoseconds longer it took this library to calculat
 |:------------|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|
 |1.0.6        |DEBUG            |8237502387529357 |397653549738     |~2,800           |~2,400           |~43,000\*        |~225,000         |
 |1.0.13       |DEBUG            |8237502387529357 |397653549738     |~2,450           |~2,350           |~38,100\*        |~208,700         |
-|1.0.14       |RELEASE          |8237502387529357 |397653549738     |~200             |~210             |~4,150\*         |~15,500          |
+|1.0.14       |RELEASE          |8237502387529357 |397653549738     |~170             |~200             |~3,950\*         |~15,400          |
 #### `HugeFloat`
 |Version      |Scheme           |Precision        |Left Number      |Right Number     |Addition         |Subtraction      |Multiplication   |Division         |
 |:------------|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|:---------------:|
 |1.0.6        |DEBUG            |100              |12345.678        |54321.012        |~8,200           |~8,300           |~24,000          |~13,000,000      |
 |1.0.13       |DEBUG            |6                |12345.678        |54321.012        |~8,000           |~8,300           |~22,000          |~410,000         |
 |1.0.13       |DEBUG            |100              |12345.678        |54321.012        |-                |-                |-                |~9,306,000       |
-|1.0.14       |RELEASE          |6                |12345.678        |54321.012        |~840             |~1,120           |~3,400           |~41,000          |
-|1.0.14       |RELEASE          |100              |12345.678        |54321.012        |-                |-                |-                |~680,000         |
+|1.0.14       |RELEASE          |6                |12345.678        |54321.012        |~790             |~1,080           |~3,300           |~39,500          |
+|1.0.14       |RELEASE          |100              |12345.678        |54321.012        |-                |-                |-                |~660,000         |
 
 ## Contributing
 Adding/improving functionality is always welcome, just make a PR.

Sources/huge-numbers/HugeInt.swift

@@ -174,7 +174,7 @@ public struct HugeInt : Hashable, Comparable, Codable, CustomStringConvertible {
         let this:HugeInt = self
         var maximum:HugeInt = maximum
         let two:HugeInt = HugeInt(is_negative: false, [2]), one:HugeInt = HugeInt.one
-        let factors:Set<HugeInt> = await withTaskGroup(of: HugeInt?.self, body: { group in
+        return await withTaskGroup(of: HugeInt?.self, body: { group in
             while maximum >= two {
                 let target_number:HugeInt = maximum
                 group.addTask {
@@ -190,7 +190,6 @@ public struct HugeInt : Hashable, Comparable, Codable, CustomStringConvertible {
             }
             return array
         })
-        return factors
     }
     /// - Warning: This function assumes self is less than or equal to the given number.
     /// - Warning: Very resource intensive when using big numbers.
@@ -480,22 +479,13 @@ internal extension HugeInt {
     static func add(bigger_numbers: [Int8], smaller_numbers: [Int8]) -> [Int8] {
         let smaller_numbers_length:Int = smaller_numbers.count
         let result_count:Int = bigger_numbers.count + 1
-        var result:[Int8] = [Int8].init(repeating: 0, count: result_count)
+        var result:[Int8] = bigger_numbers
+        result.append(0)
 
-        var remainder:Int8 = 0
         for index in 0..<smaller_numbers_length {
-            var new_value:Int8 = smaller_numbers[index] + bigger_numbers[index] + remainder
-            if new_value > 9 {
-                new_value -= 10
-                remainder = 1
-            } else {
-                remainder = 0
-            }
-            result[index] = new_value
+            result[index] += smaller_numbers[index]
         }
-        result[smaller_numbers_length] = remainder
-        for i in smaller_numbers_length..<result_count-1 {
-            result[i] += bigger_numbers[i]
+        for i in 0..<result_count {
             if result[i] > 9 {
                 result[i] -= 10
                 result[i+1] += 1
@@ -539,22 +529,14 @@ internal extension HugeInt {
     static func subtract(bigger_numbers: [Int8], smaller_numbers: [Int8]) -> [Int8] {
         let smaller_numbers_length:Int = smaller_numbers.count
         let result_count:Int = bigger_numbers.count
-        var result:[Int8] = [Int8].init(repeating: 0, count: result_count)
+        var result:[Int8] = bigger_numbers
 
         for index in 0..<smaller_numbers_length {
-            result[index] += bigger_numbers[index]
-            var value:Int8 = result[index] - smaller_numbers[index]
-            if value < 0 {
-                value += 10
-                result[index+1] -= 1
-            }
-            result[index] = value
+            result[index] -= smaller_numbers[index]
         }
-        for i in smaller_numbers_length..<result_count {
-            result[i] += bigger_numbers[i]
+        for i in 0..<result_count {
             if result[i] < 0 {
-                let value:Int8 = result[i] + 10
-                result[i] = value
+                result[i] += 10
                 result[i+1] -= 1
             }
         }

Tests/huge-numbersTests/huge_numbersTests.swift

@@ -10,7 +10,7 @@ import HugeNumbers
 
 final class huge_numbersTests: XCTestCase {
     func testExample() async throws {
-        //try await test_benchmarks()
+        try await test_benchmarks()
 
         await test_int()
         test_float()
@@ -36,12 +36,12 @@ extension huge_numbersTests {
             //try await test_benchmark_integer_addition()
             //try await test_benchmark_integer_subtraction()
             //try await test_benchmark_integer_multiplication()
-            try await test_benchmark_integer_division()
+            //try await test_benchmark_integer_division()
 
             //try await test_benchmark_float_addition()
             //try await test_benchmark_float_subtraction()
             //try await test_benchmark_float_multiplication()
-            //try await test_benchmark_float_division()
+            try await test_benchmark_float_division()
         }
     }
     @available(macOS 13.0, *)
@@ -119,7 +119,7 @@ extension huge_numbersTests {
     private func test_benchmark_float_division() async throws {
         let left_native:Float = 12345.678, right_native:Float = 54321.012
         let left:HugeFloat = HugeFloat("12345.678"), right:HugeFloat = HugeFloat("54321.012")
-        let precision:HugeInt = HugeInt("100")
+        let precision:HugeInt = HugeInt.float_precision
         try await benchmark_compare_is_faster(key1: "HugeFloat.divide", {
             let _:HugeFloat = left.divide_by(right, precision: precision)
         }, key2: "Float.divide", code2: {