1// Copyright 2022 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5// Prefer SARX/SHLX/SHRX instruction because it has less register restriction on the shift input.
6(SAR(Q|L) x y) && buildcfg.GOAMD64 >= 3 => (SARX(Q|L) x y)
7(SHL(Q|L) x y) && buildcfg.GOAMD64 >= 3 => (SHLX(Q|L) x y)
8(SHR(Q|L) x y) && buildcfg.GOAMD64 >= 3 => (SHRX(Q|L) x y)
9
10// See comments in ARM64latelower.rules for why these are here.
11(MOVLQZX x) && zeroUpper32Bits(x,3) => x
12(MOVWQZX x) && zeroUpper48Bits(x,3) => x
13(MOVBQZX x) && zeroUpper56Bits(x,3) => x
View as plain text