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 14