prevent large table stack copies in debug mode

srijs · srijs · commit e61ce6a39bbe · 2022-01-21T13:33:20.000+01:00
(see #24 for background)
diff --git a/src/table.rs b/src/table.rs
@@ -1,4 +1,7 @@
-pub const CRC32_TABLE: [[u32; 256]; 16] = [
+// NOTE: This is static instead of const to ensure that indexing into this table
+//       doesn't result in large memmoves when in debug mode, which can significantly
+//       impact performance.
+pub static CRC32_TABLE: [[u32; 256]; 16] = [
     [
         0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535,
         0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd,

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,7 @@`
`1`		`-pub const CRC32_TABLE: [[u32; 256]; 16] = [`
	`1`	`+// NOTE: This is static instead of const to ensure that indexing into this table`
	`2`	`+// doesn't result in large memmoves when in debug mode, which can significantly`
	`3`	`+// impact performance.`
	`4`	`+pub static CRC32_TABLE: [[u32; 256]; 16] = [`
`2`	`5`	`[`
`3`	`6`	`0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535,`
`4`	`7`	`0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd,`