// license that can be found in the LICENSE file.

// Parse input AST and prepare Prog structure.

package main

import (
	"fmt"
	"go/ast"
	"go/format"
	"go/parser"
	"go/scanner"
	"go/token"
	"os"
	"strings"
)

func parse(name string, src []byte, flags parser.Mode) *ast.File {
	ast1, err := parser.ParseFile(fset, name, src, flags)
	if err != nil {

	parser.allowABI = true
	testOperandParser(t, parser, amd64RuntimeOperandTests)
	testBadOperandParser(t, parser, amd64BadOperandRuntimeTests)
}

func Test386OperandParser(t *testing.T) {
	parser := newParser("386")
	testOperandParser(t, parser, x86OperandTests)
}

func TestARMOperandParser(t *testing.T) {
	parser := newParser("arm")
	testOperandParser(t, parser, armOperandTests)

decide which.

The obvious thing for cgo to do is to process the preamble, expanding
#includes and processing the corresponding C code. That would require
a full C parser and type checker that was also aware of any extensions
known to the system compiler (for example, all the GNU C extensions) as
well as the system-specific header locations and system-specific

		p.start(op)
		if name, abi, ok := p.funcAddress(); ok {
			fmt.Fprintf(w, "ref %s %s\n", name, abi)
		}
	}
}

func (p *Parser) start(operand []lex.Token) {
	p.input = operand
	p.inputPos = 0
}

// address parses the operand into a link address structure.
func (p *Parser) address(operand []lex.Token) obj.Addr {
	p.start(operand)
	addr := obj.Addr{}
	p.operand(&addr)
	return addr
}

// It then attempts to guess the specific format based on magic values.
// If the checksum fails, then FormatUnknown is returned.
func (b *block) getFormat() Format {
	// Verify checksum.
	var p parser
	value := p.parseOctal(b.toV7().chksum())
	chksum1, chksum2 := b.computeChecksum()
	if p.err != nil || (value != chksum1 && value != chksum2) {
		return FormatUnknown
	}

	// Guess the magic values.

it is a distinct program, so there are some differences.
One is in constant evaluation.
Constant expressions in the assembler are parsed using Go's operator
precedence, not the C-like precedence of the original.
Thus <code>3&amp;1&lt;&lt;2</code> is 4, not 0—it parses as <code>(3&amp;1)&lt;&lt;2</code>
not <code>3&amp;(1&lt;&lt;2)</code>.
Also, constants are always evaluated as 64-bit unsigned integers.

	"cmd/internal/objabi"
	"cmd/internal/src"
)

// Input is the main input: a stack of readers and some macro definitions.
// It also handles #include processing (by pushing onto the input stack)
// and parses and instantiates macro definitions.
type Input struct {
	Stack
	includes        []string
	beginningOfLine bool
	ifdefStack      []bool
	macros          map[string]*Macro

			// atime and ctime fields, which are often left unused.
			//
			// In order to continue reading tar files created by former, buggy
			// versions of Go, we skeptically parse the atime and ctime fields.
			// If we are unable to parse them and the prefix field looks like
			// an ASCII string, then we fallback on the pre-Go1.8 behavior
			// of treating these fields as the USTAR prefix field.
			//

func (w *Walker) parseFile(dir, file string) (*ast.File, error) {
	filename := filepath.Join(dir, file)
	if f := parsedFileCache[filename]; f != nil {
		return f, nil
	}

	f, err := parser.ParseFile(fset, filename, nil, parser.ParseComments)
	if err != nil {
		return nil, err
	}
	parsedFileCache[filename] = f

	return f, nil
}

// Disable before debugging non-obvious errors from the type-checker.

	if cond == "" {
		return true
	}
	bits, ok := parseARM64Suffix(cond)
	if !ok {
		return false
	}
	prog.Scond = bits
	return true
}

// parseARM64Suffix parses the suffix attached to an ARM64 instruction.
// The input is a single string consisting of period-separated condition
// codes, such as ".P.W". An initial period is ignored.
func parseARM64Suffix(cond string) (uint8, bool) {