stdlib: Dictionary, Set: stop overallocating the bitmap

gribozavr · gribozavr · commit d74b1834f8ab · 2016-05-23T21:12:13.000-07:00
The 'sizeInWords(forSizeInBits:)' function was supposed to return the
size in words, but returned the size in bits, overallocating the bitmap
by a factor of 32 or 64, depending on the platform.
diff --git a/stdlib/public/core/UnsafeBitMap.swift b/stdlib/public/core/UnsafeBitMap.swift
@@ -35,7 +35,7 @@ struct _UnsafeBitMap {
 
   public // @testable
   static func sizeInWords(forSizeInBits bitCount: Int) -> Int {
-    return bitCount + Int._sizeInBytes - 1 / Int._sizeInBytes
+    return (bitCount + Int._sizeInBits - 1) / Int._sizeInBits
   }
 
   public // @testable
diff --git a/validation-test/stdlib/UnsafeBitMap.swift b/validation-test/stdlib/UnsafeBitMap.swift
@@ -41,8 +41,7 @@ UnsafeBitMapTests.test("wordIndex(_:), bitIndex(_:)") {
 #endif
 }
 
-UnsafeBitMapTests.test("sizeInWords(forSizeInBits:)")
-  .xfail(.always("the API is buggy")).code {
+UnsafeBitMapTests.test("sizeInWords(forSizeInBits:)") {
   expectEqual(0, _UnsafeBitMap.sizeInWords(forSizeInBits: 0))
 #if arch(i386) || arch(arm)
   for i in 1...32 {

Original file line number	Diff line number	Diff line change
`@@ -35,7 +35,7 @@ struct _UnsafeBitMap {`
`35`	`35`
`36`	`36`	`public // @testable`
`37`	`37`	`static func sizeInWords(forSizeInBits bitCount: Int) -> Int {`
`38`		`- return bitCount + Int._sizeInBytes - 1 / Int._sizeInBytes`
	`38`	`+ return (bitCount + Int._sizeInBits - 1) / Int._sizeInBits`
`39`	`39`	`}`
`40`	`40`
`41`	`41`	`public // @testable`
Original file line number	Diff line number	Diff line change
`@@ -41,8 +41,7 @@ UnsafeBitMapTests.test("wordIndex(_:), bitIndex(_:)") {`
`41`	`41`	`#endif`
`42`	`42`	`}`
`43`	`43`
`44`		`-UnsafeBitMapTests.test("sizeInWords(forSizeInBits:)")`
`45`		`- .xfail(.always("the API is buggy")).code {`
	`44`	`+UnsafeBitMapTests.test("sizeInWords(forSizeInBits:)") {`
`46`	`45`	`expectEqual(0, _UnsafeBitMap.sizeInWords(forSizeInBits: 0))`
`47`	`46`	`#if arch(i386) \|\| arch(arm)`
`48`	`47`	`for i in 1...32 {`