cmd: simplify some handling of package paths

We have obj.Link.Pkgpath, so we don't need to pass it redundantly in
places where we already have an *obj.Link.

Also, renaming the parser's "compilingRuntime" field to "allowABI", to
match the "AllowAsmABI" name used by objabi.LookupPkgSpecial.

Finally, push the handling of GOEXPERIMENT_* flags up to cmd/asm's
main entry point, by simply appending them to flags.D.

Change-Id: I6ada134522b0cbc90d35bcb145fbe045338fefb7
Reviewed-on: https://go-review.googlesource.com/c/go/+/523297
Run-TryBot: Matthew Dempsky <[email protected]>
Reviewed-by: Cherry Mui <[email protected]>
Auto-Submit: Matthew Dempsky <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>

Author: mdempsky

src/cmd/asm/internal/asm/endtoend_test.go

@@ -29,8 +29,8 @@ func testEndToEnd(t *testing.T, goarch, file string) {
 	input := filepath.Join("testdata", file+".s")
 	architecture, ctxt := setArch(goarch)
 	architecture.Init(ctxt)
-	lexer := lex.NewLexer(input, false)
-	parser := NewParser(ctxt, architecture, lexer, false)
+	lexer := lex.NewLexer(input)
+	parser := NewParser(ctxt, architecture, lexer)
 	pList := new(obj.Plist)
 	var ok bool
 	testOut = new(strings.Builder) // The assembler writes test output to this buffer.
@@ -191,7 +191,7 @@ Diff:
 		t.Errorf(format, args...)
 		ok = false
 	}
-	obj.Flushplist(ctxt, pList, nil, "")
+	obj.Flushplist(ctxt, pList, nil)
 
 	for p := top; p != nil; p = p.Link {
 		if p.As == obj.ATEXT {
@@ -278,8 +278,8 @@ func testErrors(t *testing.T, goarch, file string, flags ...string) {
 	input := filepath.Join("testdata", file+".s")
 	architecture, ctxt := setArch(goarch)
 	architecture.Init(ctxt)
-	lexer := lex.NewLexer(input, false)
-	parser := NewParser(ctxt, architecture, lexer, false)
+	lexer := lex.NewLexer(input)
+	parser := NewParser(ctxt, architecture, lexer)
 	pList := new(obj.Plist)
 	var ok bool
 	ctxt.Bso = bufio.NewWriter(os.Stdout)
@@ -305,7 +305,7 @@ func testErrors(t *testing.T, goarch, file string, flags ...string) {
 		}
 	}
 	pList.Firstpc, ok = parser.Parse()
-	obj.Flushplist(ctxt, pList, nil, "")
+	obj.Flushplist(ctxt, pList, nil)
 	if ok && !failed {
 		t.Errorf("asm: %s had no errors", file)
 	}

src/cmd/asm/internal/asm/expr_test.go

@@ -57,7 +57,7 @@ var exprTests = []exprTest{
 }
 
 func TestExpr(t *testing.T) {
-	p := NewParser(nil, nil, nil, false) // Expression evaluation uses none of these fields of the parser.
+	p := NewParser(nil, nil, nil) // Expression evaluation uses none of these fields of the parser.
 	for i, test := range exprTests {
 		p.start(lex.Tokenize(test.input))
 		result := int64(p.expr())
@@ -113,7 +113,7 @@ func TestBadExpr(t *testing.T) {
 }
 
 func runBadTest(i int, test badExprTest, t *testing.T) (err error) {
-	p := NewParser(nil, nil, nil, false) // Expression evaluation uses none of these fields of the parser.
+	p := NewParser(nil, nil, nil) // Expression evaluation uses none of these fields of the parser.
 	p.start(lex.Tokenize(test.input))
 	return tryParse(t, func() {
 		p.expr()

src/cmd/asm/internal/asm/line_test.go

@@ -39,7 +39,7 @@ func testBadInstParser(t *testing.T, goarch string, tests []badInstTest) {
 	for i, test := range tests {
 		arch, ctxt := setArch(goarch)
 		tokenizer := lex.NewTokenizer("", strings.NewReader(test.input+"\n"), nil)
-		parser := NewParser(ctxt, arch, tokenizer, false)
+		parser := NewParser(ctxt, arch, tokenizer)
 
 		err := tryParse(t, func() {
 			parser.Parse()

src/cmd/asm/internal/asm/operand_test.go

@@ -28,7 +28,7 @@ func setArch(goarch string) (*arch.Arch, *obj.Link) {
 
 func newParser(goarch string) *Parser {
 	architecture, ctxt := setArch(goarch)
-	return NewParser(ctxt, architecture, nil, false)
+	return NewParser(ctxt, architecture, nil)
 }
 
 // tryParse executes parse func in panicOnError=true context.
@@ -76,7 +76,7 @@ func testOperandParser(t *testing.T, parser *Parser, tests []operandTest) {
 		addr := obj.Addr{}
 		parser.operand(&addr)
 		var result string
-		if parser.compilingRuntime {
+		if parser.allowABI {
 			result = obj.DconvWithABIDetail(&emptyProg, &addr)
 		} else {
 			result = obj.Dconv(&emptyProg, &addr)
@@ -91,7 +91,7 @@ func TestAMD64OperandParser(t *testing.T) {
 	parser := newParser("amd64")
 	testOperandParser(t, parser, amd64OperandTests)
 	testBadOperandParser(t, parser, amd64BadOperandTests)
-	parser.compilingRuntime = true
+	parser.allowABI = true
 	testOperandParser(t, parser, amd64RuntimeOperandTests)
 	testBadOperandParser(t, parser, amd64BadOperandRuntimeTests)
 }

src/cmd/asm/internal/asm/parse.go

@@ -21,47 +21,48 @@ import (
 	"cmd/internal/obj"
 	"cmd/internal/obj/arm64"
 	"cmd/internal/obj/x86"
+	"cmd/internal/objabi"
 	"cmd/internal/src"
 	"cmd/internal/sys"
 )
 
 type Parser struct {
-	lex              lex.TokenReader
-	lineNum          int   // Line number in source file.
-	errorLine        int   // Line number of last error.
-	errorCount       int   // Number of errors.
-	sawCode          bool  // saw code in this file (as opposed to comments and blank lines)
-	pc               int64 // virtual PC; count of Progs; doesn't advance for GLOBL or DATA.
-	input            []lex.Token
-	inputPos         int
-	pendingLabels    []string // Labels to attach to next instruction.
-	labels           map[string]*obj.Prog
-	toPatch          []Patch
-	addr             []obj.Addr
-	arch             *arch.Arch
-	ctxt             *obj.Link
-	firstProg        *obj.Prog
-	lastProg         *obj.Prog
-	dataAddr         map[string]int64 // Most recent address for DATA for this symbol.
-	isJump           bool             // Instruction being assembled is a jump.
-	compilingRuntime bool
-	errorWriter      io.Writer
+	lex           lex.TokenReader
+	lineNum       int   // Line number in source file.
+	errorLine     int   // Line number of last error.
+	errorCount    int   // Number of errors.
+	sawCode       bool  // saw code in this file (as opposed to comments and blank lines)
+	pc            int64 // virtual PC; count of Progs; doesn't advance for GLOBL or DATA.
+	input         []lex.Token
+	inputPos      int
+	pendingLabels []string // Labels to attach to next instruction.
+	labels        map[string]*obj.Prog
+	toPatch       []Patch
+	addr          []obj.Addr
+	arch          *arch.Arch
+	ctxt          *obj.Link
+	firstProg     *obj.Prog
+	lastProg      *obj.Prog
+	dataAddr      map[string]int64 // Most recent address for DATA for this symbol.
+	isJump        bool             // Instruction being assembled is a jump.
+	allowABI      bool             // Whether ABI selectors are allowed.
+	errorWriter   io.Writer
 }
 
 type Patch struct {
 	addr  *obj.Addr
 	label string
 }
 
-func NewParser(ctxt *obj.Link, ar *arch.Arch, lexer lex.TokenReader, compilingRuntime bool) *Parser {
+func NewParser(ctxt *obj.Link, ar *arch.Arch, lexer lex.TokenReader) *Parser {
 	return &Parser{
-		ctxt:             ctxt,
-		arch:             ar,
-		lex:              lexer,
-		labels:           make(map[string]*obj.Prog),
-		dataAddr:         make(map[string]int64),
-		errorWriter:      os.Stderr,
-		compilingRuntime: compilingRuntime,
+		ctxt:        ctxt,
+		arch:        ar,
+		lex:         lexer,
+		labels:      make(map[string]*obj.Prog),
+		dataAddr:    make(map[string]int64),
+		errorWriter: os.Stderr,
+		allowABI:    ctxt != nil && objabi.LookupPkgSpecial(ctxt.Pkgpath).AllowAsmABI,
 	}
 }
 
@@ -864,7 +865,7 @@ func (p *Parser) symRefAttrs(name string, issueError bool) (bool, obj.ABI) {
 		isStatic = true
 	} else if tok == scanner.Ident {
 		abistr := p.get(scanner.Ident).String()
-		if !p.compilingRuntime {
+		if !p.allowABI {
 			if issueError {
 				p.errorf("ABI selector only permitted when compiling runtime, reference was to %q", name)
 			}

src/cmd/asm/internal/asm/pseudo_test.go

@@ -64,16 +64,16 @@ func TestErroneous(t *testing.T) {
 	}
 
 	testcats := []struct {
-		compilingRuntime bool
-		tests            []errtest
+		allowABI bool
+		tests    []errtest
 	}{
 		{
-			compilingRuntime: false,
-			tests:            nonRuntimeTests,
+			allowABI: false,
+			tests:    nonRuntimeTests,
 		},
 		{
-			compilingRuntime: true,
-			tests:            runtimeTests,
+			allowABI: true,
+			tests:    runtimeTests,
 		},
 	}
 
@@ -85,7 +85,7 @@ func TestErroneous(t *testing.T) {
 
 	for _, cat := range testcats {
 		for _, test := range cat.tests {
-			parser.compilingRuntime = cat.compilingRuntime
+			parser.allowABI = cat.allowABI
 			parser.errorCount = 0
 			parser.lineNum++
 			if !parser.pseudo(test.pseudo, tokenize(test.operands)) {

src/cmd/asm/internal/lex/input.go

@@ -6,7 +6,6 @@ package lex
 
 import (
 	"fmt"
-	"internal/buildcfg"
 	"os"
 	"path/filepath"
 	"strconv"
@@ -34,33 +33,18 @@ type Input struct {
 }
 
 // NewInput returns an Input from the given path.
-func NewInput(name string, compilingRuntime bool) *Input {
+func NewInput(name string) *Input {
 	return &Input{
 		// include directories: look in source dir, then -I directories.
 		includes:        append([]string{filepath.Dir(name)}, flags.I...),
 		beginningOfLine: true,
-		macros:          predefine(flags.D, compilingRuntime),
+		macros:          predefine(flags.D),
 	}
 }
 
 // predefine installs the macros set by the -D flag on the command line.
-func predefine(defines flags.MultiFlag, compilingRuntime bool) map[string]*Macro {
+func predefine(defines flags.MultiFlag) map[string]*Macro {
 	macros := make(map[string]*Macro)
-
-	// Set macros for GOEXPERIMENTs so we can easily switch
-	// runtime assembly code based on them.
-	if compilingRuntime {
-		for _, exp := range buildcfg.Experiment.Enabled() {
-			// Define macro.
-			name := "GOEXPERIMENT_" + exp
-			macros[name] = &Macro{
-				name:   name,
-				args:   nil,
-				tokens: Tokenize("1"),
-			}
-		}
-	}
-
 	for _, name := range defines {
 		value := "1"
 		i := strings.IndexRune(name, '=')

src/cmd/asm/internal/lex/lex.go

@@ -60,8 +60,8 @@ func (t ScanToken) String() string {
 }
 
 // NewLexer returns a lexer for the named file and the given link context.
-func NewLexer(name string, compilingRuntime bool) TokenReader {
-	input := NewInput(name, compilingRuntime)
+func NewLexer(name string) TokenReader {
+	input := NewInput(name)
 	fd, err := os.Open(name)
 	if err != nil {
 		log.Fatalf("%s\n", err)

src/cmd/asm/internal/lex/lex_test.go

@@ -258,7 +258,7 @@ var lexTests = []lexTest{
 
 func TestLex(t *testing.T) {
 	for _, test := range lexTests {
-		input := NewInput(test.name, false)
+		input := NewInput(test.name)
 		input.Push(NewTokenizer(test.name, strings.NewReader(test.input), nil))
 		result := drain(input)
 		if result != test.output {
@@ -328,7 +328,7 @@ var badLexTests = []badLexTest{
 
 func TestBadLex(t *testing.T) {
 	for _, test := range badLexTests {
-		input := NewInput(test.error, false)
+		input := NewInput(test.error)
 		input.Push(NewTokenizer(test.error, strings.NewReader(test.input), nil))
 		err := firstError(input)
 		if err == nil {

src/cmd/asm/main.go

@@ -35,8 +35,6 @@ func main() {
 	if architecture == nil {
 		log.Fatalf("unrecognized architecture %s", GOARCH)
 	}
-	compilingRuntime := objabi.LookupPkgSpecial(*flags.Importpath).AllowAsmABI
-
 	ctxt := obj.Linknew(architecture.LinkArch)
 	ctxt.Debugasm = flags.PrintOut
 	ctxt.Debugvlog = flags.DebugV
@@ -77,12 +75,19 @@ func main() {
 		fmt.Fprintf(buf, "!\n")
 	}
 
+	// Set macros for GOEXPERIMENTs so we can easily switch
+	// runtime assembly code based on them.
+	if objabi.LookupPkgSpecial(ctxt.Pkgpath).AllowAsmABI {
+		for _, exp := range buildcfg.Experiment.Enabled() {
+			flags.D = append(flags.D, "GOEXPERIMENT_"+exp)
+		}
+	}
+
 	var ok, diag bool
 	var failedFile string
 	for _, f := range flag.Args() {
-		lexer := lex.NewLexer(f, compilingRuntime)
-		parser := asm.NewParser(ctxt, architecture, lexer,
-			compilingRuntime)
+		lexer := lex.NewLexer(f)
+		parser := asm.NewParser(ctxt, architecture, lexer)
 		ctxt.DiagFunc = func(format string, args ...interface{}) {
 			diag = true
 			log.Printf(format, args...)
@@ -94,7 +99,7 @@ func main() {
 			pList.Firstpc, ok = parser.Parse()
 			// reports errors to parser.Errorf
 			if ok {
-				obj.Flushplist(ctxt, pList, nil, *flags.Importpath)
+				obj.Flushplist(ctxt, pList, nil)
 			}
 		}
 		if !ok {