// Copyright 2019 The Go Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. // This file contains rules used by flagalloc and addressingmodes to // split a flag-generating merged load op into separate load and op. // Unlike with the other rules files, not all of these // rules will be applied to all values. // Rather, flagalloc will request for rules to be applied // to a particular problematic value. // These are often the exact inverse of rules in AMD64.rules, // only with the conditions removed. // // For addressingmodes, certain single instructions are slower than the two instruction // split generated here (which is different from the inputs to addressingmodes). // For example: // (CMPBconstload c (ADDQ x y)) -> (CMPBconstloadidx1 c x y) -> (CMPB c (MOVBloadidx1 x y)) (CMP(Q|L|W|B)load {sym} [off] ptr x mem) => (CMP(Q|L|W|B) (MOV(Q|L|W|B)load {sym} [off] ptr mem) x) (CMP(Q|L|W|B)constload {sym} [vo] ptr mem) && vo.Val() == 0 => (TEST(Q|L|W|B) x:(MOV(Q|L|W|B)load {sym} [vo.Off32()] ptr mem) x) (CMPQconstload {sym} [vo] ptr mem) && vo.Val() != 0 => (CMPQconst (MOVQload {sym} [vo.Off32()] ptr mem) [vo.Val32()]) (CMPLconstload {sym} [vo] ptr mem) && vo.Val() != 0 => (CMPLconst (MOVLload {sym} [vo.Off32()] ptr mem) [vo.Val32()]) (CMPWconstload {sym} [vo] ptr mem) && vo.Val() != 0 => (CMPWconst (MOVWload {sym} [vo.Off32()] ptr mem) [vo.Val16()]) (CMPBconstload {sym} [vo] ptr mem) && vo.Val() != 0 => (CMPBconst (MOVBload {sym} [vo.Off32()] ptr mem) [vo.Val8()]) (CMP(Q|L|W|B)loadidx1 {sym} [off] ptr idx x mem) => (CMP(Q|L|W|B) (MOV(Q|L|W|B)loadidx1 {sym} [off] ptr idx mem) x) (CMPQloadidx8 {sym} [off] ptr idx x mem) => (CMPQ (MOVQloadidx8 {sym} [off] ptr idx mem) x) (CMPLloadidx4 {sym} [off] ptr idx x mem) => (CMPL (MOVLloadidx4 {sym} [off] ptr idx mem) x) (CMPWloadidx2 {sym} [off] ptr idx x mem) => (CMPW (MOVWloadidx2 {sym} [off] ptr idx mem) x) (CMP(Q|L|W|B)constloadidx1 {sym} [vo] ptr idx mem) && vo.Val() == 0 => (TEST(Q|L|W|B) x:(MOV(Q|L|W|B)loadidx1 {sym} [vo.Off32()] ptr idx mem) x) (CMPQconstloadidx8 {sym} [vo] ptr idx mem) && vo.Val() == 0 => (TESTQ x:(MOVQloadidx8 {sym} [vo.Off32()] ptr idx mem) x) (CMPLconstloadidx4 {sym} [vo] ptr idx mem) && vo.Val() == 0 => (TESTL x:(MOVLloadidx4 {sym} [vo.Off32()] ptr idx mem) x) (CMPWconstloadidx2 {sym} [vo] ptr idx mem) && vo.Val() == 0 => (TESTW x:(MOVWloadidx2 {sym} [vo.Off32()] ptr idx mem) x) (CMPQconstloadidx1 {sym} [vo] ptr idx mem) && vo.Val() != 0 => (CMPQconst (MOVQloadidx1 {sym} [vo.Off32()] ptr idx mem) [vo.Val32()]) (CMPLconstloadidx1 {sym} [vo] ptr idx mem) && vo.Val() != 0 => (CMPLconst (MOVLloadidx1 {sym} [vo.Off32()] ptr idx mem) [vo.Val32()]) (CMPWconstloadidx1 {sym} [vo] ptr idx mem) && vo.Val() != 0 => (CMPWconst (MOVWloadidx1 {sym} [vo.Off32()] ptr idx mem) [vo.Val16()]) (CMPBconstloadidx1 {sym} [vo] ptr idx mem) && vo.Val() != 0 => (CMPBconst (MOVBloadidx1 {sym} [vo.Off32()] ptr idx mem) [vo.Val8()]) (CMPQconstloadidx8 {sym} [vo] ptr idx mem) && vo.Val() != 0 => (CMPQconst (MOVQloadidx8 {sym} [vo.Off32()] ptr idx mem) [vo.Val32()]) (CMPLconstloadidx4 {sym} [vo] ptr idx mem) && vo.Val() != 0 => (CMPLconst (MOVLloadidx4 {sym} [vo.Off32()] ptr idx mem) [vo.Val32()]) (CMPWconstloadidx2 {sym} [vo] ptr idx mem) && vo.Val() != 0 => (CMPWconst (MOVWloadidx2 {sym} [vo.Off32()] ptr idx mem) [vo.Val16()])