4 Commits

Author	SHA1	Message	Date
Alan Donovan	b7f0150d16	container/intsets: popcount: use POPCNT on amd64, Hacker's Delight algorithm on 386 ... This function accounts for 2% of "godoc -analysis=pointer" and this change makes it twice as fast---and simpler. Added test and benchmark. Change-Id: I8578fa42dce34df057d81f6c522a7b4e0506d09d Reviewed-on: https://go-review.googlesource.com/15211 Run-TryBot: Robert Griesemer <gri@golang.org> Reviewed-by: Ilya Tocar <ilya.tocar@intel.com> Reviewed-by: Robert Griesemer <gri@golang.org>	2015-10-01 19:57:28 +00:00
Alan Donovan	fd72015344	go.tools/container/intsets: increase block size to 256 bits. ... This consistently yields better performance with go/pointer. Also: return int not word from ntz(). LGTM=gri R=gri CC=golang-codereviews https://golang.org/cl/97570044	2014-05-30 13:21:36 -04:00
Alan Donovan	e1b97610f0	go.tools/container/intsets: fix compile error on 32-bit platforms. ... Also, fix typo. LGTM=gri R=gri CC=golang-codereviews https://golang.org/cl/99310043	2014-05-15 14:03:05 -04:00
Alan Donovan	61c5c64029	go.tools/container/intsets: Sparse: a space-efficient representation for ordered sets of int values. ... intsets.Sparse is a sparse bit vector. It uses space proportional to the number of elements, not the maximum element (as is the case for a dense bit vector). A forthcoming CL will make use of it in go/pointer, where it reduces solve time by 78%. A similar representation is used for Andersen's analysis in gcc and LLVM. + Tests. LGTM=sameer, crawshaw, gri R=gri CC=crawshaw, golang-codereviews, sameer https://golang.org/cl/10837043	2014-05-14 17:54:14 -04:00