github.com/bir3/gocompiler@v0.3.205/src/cmd/compile/internal/ssa/_gen/AMD64latelower.rules (about)

     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)