cmd/compile/internal: optimizing add+sll rule using ALSLV instruction on loong64
Reduce the number of go toolchain instructions on loong64 as follows:
file before after Δ %
go
1573148 1571708 -1,440 -0.0915%
gofmt 320578 320090 -488 -0.1522%
asm 555066 554406 -660 -0.1189%
cgo 481566 480926 -640 -0.1329%
compile
2475962 2473880 -2,082 -0.0841%
cover 516536 515920 -616 -0.1193%
link 702172 701404 -768 -0.1094%
preprofile 238626 238274 -352 -0.1475%
vet 792928 792100 -828 -0.1044%
Change-Id: I61e462726835959c60e1b4e5256d4020202418ab
Reviewed-on: https://go-review.googlesource.com/c/go/+/693877
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: abner chenc <chenguoqi@loongson.cn>