Make condvar_table hash function bijective

DouglasDwyer · DouglasDwyer · commit 35f4d24e12d2 · 2025-11-20T08:17:10.000-05:00
diff --git a/src/condvar_table.rs b/src/condvar_table.rs
@@ -81,7 +81,7 @@ fn entry_for_ptr(ptr: *const ()) -> u8 {
     let x_64 = ptr as u64;
     let x_32 = (x_64 >> 32) as u32 ^ x_64 as u32;
     let x_16 = (x_32 >> 16) as u16 ^ x_32 as u16;
-    (x_16 >> 8) as u8 ^ (x_16 >> 2) as u8
+    (x_16 >> 8) as u8 ^ x_16 as u8
 }
 
 /// Holds metadata that gets written while locking.

Original file line number	Diff line number	Diff line change
`@@ -81,7 +81,7 @@ fn entry_for_ptr(ptr: *const ()) -> u8 {`
`81`	`81`	`let x_64 = ptr as u64;`
`82`	`82`	`let x_32 = (x_64 >> 32) as u32 ^ x_64 as u32;`
`83`	`83`	`let x_16 = (x_32 >> 16) as u16 ^ x_32 as u16;`
`84`		`- (x_16 >> 8) as u8 ^ (x_16 >> 2) as u8`
	`84`	`+ (x_16 >> 8) as u8 ^ x_16 as u8`
`85`	`85`	`}`
`86`	`86`
`87`	`87`	`/// Holds metadata that gets written while locking.`