Instead of using container/heap package, implement a simple
specialized heap algorithm for the work queue in the deadcode
pass, to avoid allocations and function pointer calls.
Linking cmd/compile,
name old time/op new time/op delta
Deadcode_GC 59.8ms ± 4% 42.2ms ± 4% -29.45% (p=0.008 n=5+5)
name old alloc/op new alloc/op delta
Deadcode_GC 3.53MB ± 0% 2.10MB ± 0% -40.57% (p=0.008 n=5+5)
name old allocs/op new allocs/op delta
Deadcode_GC 187k ± 0% 8k ± 0% -95.48% (p=0.008 n=5+5)
Change-Id: Ibb21801d5b8e4a7eaf429856702e02720cd1772f
Reviewed-on: https://go-review.googlesource.com/c/go/+/236565
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Cherry Zhang