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[dev.cc] cmd/asm: add ppc64

Fairly straightforward. A couple of unusual addressing tricks.
Also added the ability to write R(10) to mean R10. PPC64 uses
this for a couple of large register spaces. It appears for ARM now
as well, since I saw some uses of that before, although I rewrote
them in our source. I could put it in for 386 and amd64 but it's
not worth it.

Change-Id: I3ffd7ffa62d511b95b92c3c75b9f1d621f5393b6
Reviewed-on: https://go-review.googlesource.com/5282
Reviewed-by: Russ Cox <rsc@golang.org>
This commit is contained in:
Rob Pike 2015-02-18 20:30:55 -08:00
parent 6acd5a65b2
commit e559c5cce2
6 changed files with 419 additions and 77 deletions

View File

@ -8,7 +8,8 @@ import (
"cmd/internal/obj"
"cmd/internal/obj/arm"
"cmd/internal/obj/i386" // == 386
"cmd/internal/obj/x86" // == amd64
"cmd/internal/obj/ppc64"
"cmd/internal/obj/x86" // == amd64
"fmt"
)
@ -26,7 +27,11 @@ type Arch struct {
// Map of instruction names to enumeration.
Instructions map[string]int
// Map of register names to enumeration.
Registers map[string]int16
Register map[string]int16
// Table of register prefix names. These are things like R for R(0) and SPR for SPR(268).
RegisterPrefix map[string]bool
// RegisterNumber converts R(10) into arm.REG_R10.
RegisterNumber func(string, int16) (int16, bool)
// Instructions that take one operand whose result is a destination.
UnaryDestination map[int]bool
// Instruction is a jump.
@ -37,6 +42,12 @@ type Arch struct {
Dconv func(p *obj.Prog, flag int, a *obj.Addr) string
}
// nilRegisterNumber is the register number function for architectures
// that do not accept the R(N) notation. It always returns failure.
func nilRegisterNumber(name string, n int16) (int16, bool) {
return 0, false
}
var Pseudos = map[string]int{
"DATA": obj.ADATA,
"FUNCDATA": obj.AFUNCDATA,
@ -60,6 +71,10 @@ func Set(GOARCH string) *Arch {
return a
case "arm":
return archArm()
case "ppc64":
a := archPPC64()
a.LinkArch = &ppc64.Linkppc64
return a
}
return nil
}
@ -69,16 +84,17 @@ func jump386(word string) bool {
}
func arch386() *Arch {
registers := make(map[string]int16)
register := make(map[string]int16)
// Create maps for easy lookup of instruction names etc.
// TODO: Should this be done in obj for us?
for i, s := range i386.Register {
registers[s] = int16(i + i386.REG_AL)
register[s] = int16(i + i386.REG_AL)
}
// Pseudo-registers.
registers["SB"] = RSB
registers["FP"] = RFP
registers["PC"] = RPC
register["SB"] = RSB
register["FP"] = RFP
register["PC"] = RPC
// Prefixes not used on this architecture.
instructions := make(map[string]int)
for i, s := range i386.Anames {
@ -162,7 +178,9 @@ func arch386() *Arch {
return &Arch{
LinkArch: &i386.Link386,
Instructions: instructions,
Registers: registers,
Register: register,
RegisterPrefix: nil,
RegisterNumber: nilRegisterNumber,
UnaryDestination: unaryDestination,
IsJump: jump386,
Aconv: i386.Aconv,
@ -171,16 +189,17 @@ func arch386() *Arch {
}
func archAmd64() *Arch {
registers := make(map[string]int16)
register := make(map[string]int16)
// Create maps for easy lookup of instruction names etc.
// TODO: Should this be done in obj for us?
for i, s := range x86.Register {
registers[s] = int16(i + x86.REG_AL)
register[s] = int16(i + x86.REG_AL)
}
// Pseudo-registers.
registers["SB"] = RSB
registers["FP"] = RFP
registers["PC"] = RPC
register["SB"] = RSB
register["FP"] = RFP
register["PC"] = RPC
// Register prefix not used on this architecture.
instructions := make(map[string]int)
for i, s := range x86.Anames {
@ -271,7 +290,9 @@ func archAmd64() *Arch {
return &Arch{
LinkArch: &x86.Linkamd64,
Instructions: instructions,
Registers: registers,
Register: register,
RegisterPrefix: nil,
RegisterNumber: nilRegisterNumber,
UnaryDestination: unaryDestination,
IsJump: jump386,
Aconv: x86.Aconv,
@ -280,26 +301,30 @@ func archAmd64() *Arch {
}
func archArm() *Arch {
registers := make(map[string]int16)
register := make(map[string]int16)
// Create maps for easy lookup of instruction names etc.
// TODO: Should this be done in obj for us?
// Note that there is no list of names as there is for 386 and amd64.
// TODO: Are there aliases we need to add?
for i := arm.REG_R0; i < arm.REG_SPSR; i++ {
registers[arm.Rconv(i)] = int16(i)
register[arm.Rconv(i)] = int16(i)
}
// Avoid unintentionally clobbering g using R10.
delete(registers, "R10")
registers["g"] = arm.REG_R10
delete(register, "R10")
register["g"] = arm.REG_R10
for i := 0; i < 16; i++ {
registers[fmt.Sprintf("C%d", i)] = int16(i)
register[fmt.Sprintf("C%d", i)] = int16(i)
}
// Pseudo-registers.
registers["SB"] = RSB
registers["FP"] = RFP
registers["PC"] = RPC
registers["SP"] = RSP
register["SB"] = RSB
register["FP"] = RFP
register["PC"] = RPC
register["SP"] = RSP
registerPrefix := map[string]bool{
"F": true,
"R": true,
}
instructions := make(map[string]int)
for i, s := range arm.Anames {
@ -318,10 +343,72 @@ func archArm() *Arch {
return &Arch{
LinkArch: &arm.Linkarm,
Instructions: instructions,
Registers: registers,
Register: register,
RegisterPrefix: registerPrefix,
RegisterNumber: armRegisterNumber,
UnaryDestination: unaryDestination,
IsJump: jumpArm,
Aconv: arm.Aconv,
Dconv: arm.Dconv,
}
}
func archPPC64() *Arch {
register := make(map[string]int16)
// Create maps for easy lookup of instruction names etc.
// TODO: Should this be done in obj for us?
// Note that there is no list of names as there is for 386 and amd64.
for i := ppc64.REG_R0; i <= ppc64.REG_R31; i++ {
register[ppc64.Rconv(i)] = int16(i)
}
for i := ppc64.REG_F0; i <= ppc64.REG_F31; i++ {
register[ppc64.Rconv(i)] = int16(i)
}
for i := ppc64.REG_C0; i <= ppc64.REG_C7; i++ {
// TODO: Rconv prints these as C7 but the input syntax requires CR7.
register[fmt.Sprintf("CR%d", i-ppc64.REG_C0)] = int16(i)
}
for i := ppc64.REG_MSR; i <= ppc64.REG_CR; i++ {
register[ppc64.Rconv(i)] = int16(i)
}
register["CR"] = ppc64.REG_CR
register["XER"] = ppc64.REG_XER
register["LR"] = ppc64.REG_LR
register["CTR"] = ppc64.REG_CTR
register["FPSCR"] = ppc64.REG_FPSCR
register["MSR"] = ppc64.REG_MSR
// Pseudo-registers.
register["SB"] = RSB
register["FP"] = RFP
register["PC"] = RPC
// Avoid unintentionally clobbering g using R30.
delete(register, "R30")
register["g"] = ppc64.REG_R30
registerPrefix := map[string]bool{
"CR": true,
"F": true,
"R": true,
"SPR": true,
}
instructions := make(map[string]int)
for i, s := range ppc64.Anames {
instructions[s] = i
}
// Annoying aliases.
instructions["BR"] = ppc64.ABR
instructions["BL"] = ppc64.ABL
instructions["RETURN"] = ppc64.ARETURN
return &Arch{
LinkArch: &ppc64.Linkppc64,
Instructions: instructions,
Register: register,
RegisterPrefix: registerPrefix,
RegisterNumber: ppc64RegisterNumber,
UnaryDestination: nil,
IsJump: jumpPPC64,
Aconv: ppc64.Aconv,
Dconv: ppc64.Dconv,
}
}

View File

@ -188,3 +188,16 @@ func parseARMCondition(cond string) (uint8, bool) {
}
return bits, true
}
func armRegisterNumber(name string, n int16) (int16, bool) {
if n < 0 || 15 < n {
return 0, false
}
switch name {
case "R":
return arm.REG_R0 + n, true
case "F":
return arm.REG_F0 + n, true
}
return 0, false
}

View File

@ -0,0 +1,63 @@
// Copyright 2015 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 encapsulates some of the odd characteristics of the ARM
// instruction set, to minimize its interaction with the core of the
// assembler.
package arch
import "cmd/internal/obj/ppc64"
func jumpPPC64(word string) bool {
switch word {
case "BC", "BCL", "BEQ", "BGE", "BGT", "BL", "BLE", "BLT", "BNE", "BR", "BVC", "BVS", "CALL":
return true
}
return false
}
// IsPPC64RLD reports whether the op (as defined by an ppc64.A* constant) is
// one of the RLD-like instructions that require special handling.
func IsPPC64RLD(op int) bool {
switch op {
case ppc64.ARLDC, ppc64.ARLDCCC, ppc64.ARLDCL, ppc64.ARLDCLCC,
ppc64.ARLDCR, ppc64.ARLDCRCC, ppc64.ARLDMI, ppc64.ARLDMICC,
ppc64.ARLWMI, ppc64.ARLWMICC, ppc64.ARLWNM, ppc64.ARLWNMCC:
return true
}
return false
}
// IsPPC64CMP reports whether the op (as defined by an ppc64.A* constant) is
// one of the CMP instructions that require special handling.
func IsPPC64CMP(op int) bool {
switch op {
case ppc64.ACMP, ppc64.ACMPU, ppc64.ACMPW, ppc64.ACMPWU:
return true
}
return false
}
func ppc64RegisterNumber(name string, n int16) (int16, bool) {
switch name {
case "CR":
if 0 <= n && n <= 7 {
return ppc64.REG_C0 + n, true
}
case "F":
if 0 <= n && n <= 31 {
return ppc64.REG_F0 + n, true
}
case "R":
if 0 <= n && n <= 31 {
return ppc64.REG_R0 + n, true
}
case "SPR":
if 0 <= n && n <= 1024 {
return ppc64.REG_SPR0 + n, true
}
}
return 0, false
}

View File

@ -13,6 +13,7 @@ import (
"cmd/asm/internal/lex"
"cmd/internal/obj"
"cmd/internal/obj/arm"
"cmd/internal/obj/ppc64"
)
// TODO: configure the architecture
@ -292,23 +293,37 @@ func (p *Parser) asmFuncData(word string, operands [][]lex.Token) {
// JMP 3(PC)
func (p *Parser) asmJump(op int, cond string, a []obj.Addr) {
var target *obj.Addr
switch len(a) {
case 1:
target = &a[0]
default:
p.errorf("wrong number of arguments to %s instruction", p.arch.Aconv(op))
}
prog := &obj.Prog{
Ctxt: p.linkCtxt,
Lineno: p.histLineNum,
As: int16(op),
}
switch len(a) {
case 1:
target = &a[0]
case 3:
if p.arch.Thechar == '9' {
target = &a[2]
// Special 3-operand jumps.
// First two must be constants.
prog.From = obj.Addr{
Type: obj.TYPE_CONST,
Offset: p.getConstant(prog, op, &a[0]),
}
prog.Reg = int16(ppc64.REG_R0 + p.getConstant(prog, op, &a[1]))
break
}
fallthrough
default:
p.errorf("wrong number of arguments to %s instruction", p.arch.Aconv(op))
return
}
switch {
case target.Type == obj.TYPE_BRANCH:
// JMP 4(PC)
prog.To = obj.Addr{
Type: obj.TYPE_BRANCH,
Offset: p.pc + 1 + target.Offset, // +1 because p.pc is incremented in link, below.
Offset: p.pc + 1 + target.Offset, // +1 because p.pc is incremented in append, below.
}
case target.Type == obj.TYPE_REG:
// JMP R1
@ -322,6 +337,10 @@ func (p *Parser) asmJump(op int, cond string, a []obj.Addr) {
prog.To.Type = obj.TYPE_INDIR
case target.Type == obj.TYPE_MEM && target.Reg == 0 && target.Offset == 0:
// JMP exit
if target.Sym == nil {
// Parse error left name unset.
return
}
targetProg := p.labels[target.Sym.Name]
if targetProg == nil {
p.toPatch = append(p.toPatch, Patch{prog, target.Sym.Name})
@ -329,8 +348,12 @@ func (p *Parser) asmJump(op int, cond string, a []obj.Addr) {
p.branch(prog, targetProg)
}
case target.Type == obj.TYPE_MEM && target.Name == obj.NAME_NONE:
// JMP 4(PC)
// JMP 4(R0)
prog.To = *target
// On the ppc64, 9a encodes BR (CTR) as BR CTR. We do the same.
if p.arch.Thechar == '9' && target.Offset == 0 {
prog.To.Type = obj.TYPE_REG
}
default:
p.errorf("cannot assemble jump %+v", target)
}
@ -452,6 +475,31 @@ func (p *Parser) asmInstruction(op int, cond string, a []obj.Addr) {
default:
p.errorf("expected offset or register for 3rd operand")
}
case '9':
if arch.IsPPC64CMP(op) {
// CMPW etc.; third argument is a CR register that goes into prog.Reg.
prog.From = a[0]
prog.Reg = p.getRegister(prog, op, &a[2])
prog.To = a[1]
break
}
// Arithmetic. Choices are:
// reg reg reg
// imm reg reg
// reg imm reg
// If the immediate is the middle argument, use From3.
switch a[1].Type {
case obj.TYPE_REG:
prog.From = a[0]
prog.Reg = p.getRegister(prog, op, &a[1])
prog.To = a[2]
case obj.TYPE_CONST:
prog.From = a[0]
prog.From3 = a[1]
prog.To = a[2]
default:
p.errorf("invalid addressing modes for %s instruction", p.arch.Aconv(op))
}
default:
p.errorf("TODO: implement three-operand instructions for this architecture")
}
@ -469,6 +517,14 @@ func (p *Parser) asmInstruction(op int, cond string, a []obj.Addr) {
prog.Reg = r1
break
}
if p.arch.Thechar == '9' && arch.IsPPC64RLD(op) {
// 2nd operand is always a register.
prog.From = a[0]
prog.Reg = p.getRegister(prog, op, &a[1])
prog.From3 = a[2]
prog.To = a[3]
break
}
p.errorf("can't handle %s instruction with 4 operands", p.arch.Aconv(op))
case 6:
// MCR and MRC on ARM

View File

@ -5,6 +5,7 @@
package asm
import (
"os"
"testing"
"cmd/asm/internal/arch"
@ -15,10 +16,10 @@ import (
// A simple in-out test: Do we print what we parse?
func newParser(goarch string) *Parser {
os.Setenv("GOOS", "linux") // obj can handle this OS for all architectures.
architecture := arch.Set(goarch)
ctxt := obj.Linknew(architecture.LinkArch)
parser := NewParser(ctxt, architecture, nil)
return parser
return NewParser(ctxt, architecture, nil)
}
func testOperandParser(t *testing.T, parser *Parser, tests []operandTest) {
@ -34,15 +35,15 @@ func testOperandParser(t *testing.T, parser *Parser, tests []operandTest) {
}
func testX86RegisterPair(t *testing.T, parser *Parser) {
// Special case for AX:DX, which is really two operands so isn't print correcctly
// Special case for AX:DX, which is really two operands so isn't printed correcctly
// by Aconv, but is OK by the -S output.
parser.start(lex.Tokenize("AX:BX)"))
addr := obj.Addr{}
parser.operand(&addr)
want := obj.Addr{
Type: obj.TYPE_REG,
Reg: parser.arch.Registers["AX"],
Class: int8(parser.arch.Registers["BX"]), // TODO: clean up how this is encoded in parse.go
Reg: parser.arch.Register["AX"],
Class: int8(parser.arch.Register["BX"]), // TODO: clean up how this is encoded in parse.go
}
if want != addr {
t.Errorf("AX:DX: expected %+v got %+v", want, addr)
@ -66,6 +67,11 @@ func TestARMOperandParser(t *testing.T) {
testOperandParser(t, parser, armOperandTests)
}
func TestPPC64OperandParser(t *testing.T) {
parser := newParser("ppc64")
testOperandParser(t, parser, ppc64OperandTests)
}
type operandTest struct {
input, output string
}
@ -251,12 +257,12 @@ var armOperandTests = []operandTest{
{"-12(R4)", "-12(R4)"},
{"0(PC)", "0(PC)"},
{"1024", "1024"},
{"12(R1)", "12(R1)"},
{"12(R(1))", "12(R1)"},
{"12(R13)", "12(R13)"},
{"R0", "R0"},
{"R0->(32-1)", "R0->31"},
{"R0<<R1", "R0<<R1"},
{"R0>>R1", "R0>>R1"},
{"R0>>R(1)", "R0>>R1"},
{"R0@>(32-1)", "R0@>31"},
{"R1", "R1"},
{"R11", "R11"},
@ -268,6 +274,7 @@ var armOperandTests = []operandTest{
{"R2", "R2"},
{"R3", "R3"},
{"R4", "R4"},
{"R(4)", "R4"},
{"R5", "R5"},
{"R6", "R6"},
{"R7", "R7"},
@ -275,6 +282,7 @@ var armOperandTests = []operandTest{
// TODO: Fix Dconv to handle these. MOVM print shows the registers.
{"[R0,R1,g,R15]", "$33795"},
{"[R0-R7]", "$255"},
{"[R(0)-R(7)]", "$255"},
{"[R0]", "$1"},
{"[R1-R12]", "$8190"},
{"armCAS64(SB)", "armCAS64+0(SB)"},
@ -286,3 +294,90 @@ var armOperandTests = []operandTest{
{"runtime·_sfloat2(SB)", "runtime._sfloat2+0(SB)"},
{"·AddUint32(SB)", "\"\".AddUint32+0(SB)"},
}
var ppc64OperandTests = []operandTest{
{"$((1<<63)-1)", "$0x7fffffffffffffff"},
{"$(-64*1024)", "$-65536"},
{"$(1024 * 8)", "$8192"},
{"$-1", "$-1"},
{"$-24(R4)", "$-24(R4)"},
{"$0", "$0"},
{"$0(R1)", "$0(R1)"},
{"$0.5", "$0.5"},
{"$0x7000", "$28672"},
{"$0x88888eef", "$0x88888eef"},
{"$1", "$1"},
{"$_main<>(SB)", "$_main<>+0(SB)"},
{"$argframe+0(FP)", "$argframe+0(FP)"},
{"$runtime·tlsg(SB)", "$runtime.tlsg(SB)"},
{"$~3", "$-4"},
{"(-288-3*8)(R1)", "-312(R1)"},
{"(16)(R7)", "16(R7)"},
{"(8)(g)", "8(R30)"}, // TODO: Should print 8(g)
{"(CTR)", "0(CTR)"},
{"(R0)", "0(R0)"},
{"(R3)", "0(R3)"},
{"(R4)", "0(R4)"},
{"(R5)", "0(R5)"},
{"-1(R4)", "-1(R4)"},
{"-1(R5)", "-1(R5)"},
{"6(PC)", "6(APC)"}, // TODO: Should print 6(PC).
{"CR7", "C7"}, // TODO: Should print CR7.
{"CTR", "CTR"},
{"F14", "F14"},
{"F15", "F15"},
{"F16", "F16"},
{"F17", "F17"},
{"F18", "F18"},
{"F19", "F19"},
{"F20", "F20"},
{"F21", "F21"},
{"F22", "F22"},
{"F23", "F23"},
{"F24", "F24"},
{"F25", "F25"},
{"F26", "F26"},
{"F27", "F27"},
{"F28", "F28"},
{"F29", "F29"},
{"F30", "F30"},
{"F31", "F31"},
{"LR", "LR"},
{"R0", "R0"},
{"R1", "R1"},
{"R11", "R11"},
{"R12", "R12"},
{"R13", "R13"},
{"R14", "R14"},
{"R15", "R15"},
{"R16", "R16"},
{"R17", "R17"},
{"R18", "R18"},
{"R19", "R19"},
{"R2", "R2"},
{"R20", "R20"},
{"R21", "R21"},
{"R22", "R22"},
{"R23", "R23"},
{"R24", "R24"},
{"R25", "R25"},
{"R26", "R26"},
{"R27", "R27"},
{"R28", "R28"},
{"R29", "R29"},
{"R3", "R3"},
{"R31", "R31"},
{"R4", "R4"},
{"R5", "R5"},
{"R6", "R6"},
{"R7", "R7"},
{"R8", "R8"},
{"R9", "R9"},
{"SPR(269)", "SPR(269)"},
{"a+0(FP)", "a+0(FP)"},
{"g", "R30"}, // TODO: Should print g.
{"ret+8(FP)", "ret+8(FP)"},
{"runtime·abort(SB)", "runtime.abort(SB)"},
{"·AddUint32(SB)", "\"\".AddUint32(SB)"},
{"·trunc(SB)", "\"\".trunc(SB)"},
}

View File

@ -226,6 +226,7 @@ func (p *Parser) parseScale(s string) int8 {
// operand parses a general operand and stores the result in *a.
func (p *Parser) operand(a *obj.Addr) bool {
// fmt.Printf("Operand: %v\n", p.input)
if len(p.input) == 0 {
p.errorf("empty operand: cannot happen")
return false
@ -250,9 +251,10 @@ func (p *Parser) operand(a *obj.Addr) bool {
// Symbol: sym±offset(SB)
tok := p.next()
if tok.ScanToken == scanner.Ident && !p.isRegister(tok.String()) {
name := tok.String()
if tok.ScanToken == scanner.Ident && !p.atStartOfRegister(name) {
// We have a symbol. Parse $sym±offset(symkind)
p.symbolReference(a, tok.String(), prefix)
p.symbolReference(a, name, prefix)
// fmt.Printf("SYM %s\n", p.arch.Dconv(&emptyProg, 0, a))
if p.peek() == scanner.EOF {
return true
@ -270,7 +272,7 @@ func (p *Parser) operand(a *obj.Addr) bool {
}
// Register: R1
if tok.ScanToken == scanner.Ident && p.isRegister(tok.String()) {
if tok.ScanToken == scanner.Ident && p.atStartOfRegister(name) {
if lex.IsRegisterShift(p.peek()) {
// ARM shifted register such as R1<<R2 or R1>>2.
a.Type = obj.TYPE_SHIFT
@ -280,10 +282,10 @@ func (p *Parser) operand(a *obj.Addr) bool {
p.next()
tok := p.next()
name := tok.String()
if !p.isRegister(name) {
if !p.atStartOfRegister(name) {
p.errorf("expected register; found %s", name)
}
a.Reg = p.arch.Registers[name]
a.Reg, _ = p.registerReference(name)
p.get(')')
}
} else if r1, r2, scale, ok := p.register(tok.String(), prefix); ok {
@ -312,7 +314,7 @@ func (p *Parser) operand(a *obj.Addr) bool {
// Could be parenthesized expression or (R).
rname := p.next().String()
p.back()
haveConstant = !p.isRegister(rname)
haveConstant = !p.atStartOfRegister(rname)
if !haveConstant {
p.back() // Put back the '('.
}
@ -368,18 +370,49 @@ func (p *Parser) operand(a *obj.Addr) bool {
return true
}
// isRegister reports whether the token is a register.
func (p *Parser) isRegister(name string) bool {
_, present := p.arch.Registers[name]
return present
// atStartOfRegister reports whether the parser is at the start of a register definition.
func (p *Parser) atStartOfRegister(name string) bool {
// Simple register: R10.
_, present := p.arch.Register[name]
if present {
return true
}
// Parenthesized register: R(10).
return p.arch.RegisterPrefix[name] && p.peek() == '('
}
// register parses a register reference where there is no symbol present (as in 4(R0) not sym(SB)).
// registerReference parses a register given either the name, R10, or a parenthesized form, SPR(10).
func (p *Parser) registerReference(name string) (int16, bool) {
r, present := p.arch.Register[name]
if present {
return r, true
}
if !p.arch.RegisterPrefix[name] {
p.errorf("expected register; found %s", name)
return 0, false
}
p.get('(')
tok := p.get(scanner.Int)
num, err := strconv.ParseInt(tok.String(), 10, 16)
p.get(')')
if err != nil {
p.errorf("parsing register list: %s", err)
return 0, false
}
r, ok := p.arch.RegisterNumber(name, int16(num))
if !ok {
p.errorf("illegal register %s(%d)", name, r)
return 0, false
}
return r, true
}
// register parses a full register reference where there is no symbol present (as in 4(R0) or R(10) but not sym(SB))
// including forms involving multiple registers such as R1:R2.
func (p *Parser) register(name string, prefix rune) (r1, r2 int16, scale int8, ok bool) {
// R1 or R1:R2 R1,R2 or R1*scale.
var present bool
r1, present = p.arch.Registers[name]
if !present {
// R1 or R(1) R1:R2 R1,R2 or R1*scale.
r1, ok = p.registerReference(name)
if !ok {
return
}
if prefix != 0 {
@ -392,16 +425,18 @@ func (p *Parser) register(name string, prefix rune) (r1, r2 int16, scale int8, o
case ':':
if char != '6' && char != '8' {
p.errorf("illegal register pair syntax")
return
}
case ',':
if char != '5' {
p.errorf("illegal register pair syntax")
return
}
}
name := p.next().String()
r2, present = p.arch.Registers[name]
if !present {
p.errorf("%s not a register", name)
r2, ok = p.registerReference(name)
if !ok {
return
}
}
if p.peek() == '*' {
@ -415,18 +450,18 @@ func (p *Parser) register(name string, prefix rune) (r1, r2 int16, scale int8, o
// registerShift parses an ARM shifted register reference and returns the encoded representation.
// There is known to be a register (current token) and a shift operator (peeked token).
func (p *Parser) registerShift(name string, prefix rune) int64 {
if prefix != 0 {
p.errorf("prefix %c not allowed for shifted register: $%s", prefix, name)
}
// R1 op R2 or r1 op constant.
// op is:
// "<<" == 0
// ">>" == 1
// "->" == 2
// "@>" == 3
r1, present := p.arch.Registers[name]
if !present {
p.errorf("shift of non-register %s", name)
}
if prefix != 0 {
p.errorf("prefix %c not allowed for shifted register: $%s", prefix, name)
r1, ok := p.registerReference(name)
if !ok {
return 0
}
var op int16
switch p.next().ScanToken {
@ -444,8 +479,8 @@ func (p *Parser) registerShift(name string, prefix rune) int64 {
var count int16
switch tok.ScanToken {
case scanner.Ident:
r2, present := p.arch.Registers[str]
if !present {
r2, ok := p.registerReference(str)
if !ok {
p.errorf("rhs of shift must be register or integer: %s", str)
}
count = (r2&15)<<8 | 1<<4
@ -632,26 +667,19 @@ func (p *Parser) registerList(a *obj.Addr) {
a.Offset = int64(bits)
}
// register number is ARM-specific. It returns the number of the specified register.
func (p *Parser) registerNumber(name string) uint16 {
if !p.isRegister(name) {
p.errorf("expected register; found %s", name)
}
// Register must be of the form R0 through R15.
// On ARM, g is register 10.
if p.arch.Thechar == '5' && name == "g" {
return 10
}
if name[0] != 'R' {
p.errorf("expected g or R0 through R15; found %s", name)
}
num, err := strconv.ParseUint(name[1:], 10, 8)
if err != nil {
p.errorf("parsing register list: %s", err)
r, ok := p.registerReference(name)
if !ok {
return 0
}
if num > 15 {
p.errorf("illegal register %s in register list", name)
}
return uint16(num)
return uint16(r - p.arch.Register["R0"])
}
// Note: There are two changes in the expression handling here