// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Package dwarf generates DWARF debugging information.
// DWARF generation is split between the compiler and the linker,
// this package contains the shared code.
package dwarf

import (
	"bytes"
	"cmd/internal/src"
	"errors"
	"fmt"
	"internal/buildcfg"
	"os/exec"
	"sort"
	"strconv"
	"strings"

	}
	return binary.Write(r.f, r.order, data)
}

// machoCombineDwarf merges dwarf info generated by dsymutil into a macho executable.
//
// With internal linking, DWARF is embedded into the executable, this lets us do the
// same for external linking.
// exef is the file of the executable with no DWARF. It must have enough room in the macho
// header to add the DWARF sections. (Use ld's -headerpad option)
// exem is the macho representation of exef.

		if err != nil {
			t.Fatalf("error reading DWARF: %v", err)
		}
		switch entry.Tag {
		case dwarf.TagArrayType, dwarf.TagPointerType, dwarf.TagStructType, dwarf.TagBaseType, dwarf.TagSubroutineType, dwarf.TagTypedef:
		default:
			continue
		}
		typ, err := d.Type(entry.Offset)
		if err != nil {
			t.Fatalf("can't read type: %v", err)
		}
		if typ.Size() < 0 {

func assembleInlines(fnsym *obj.LSym, dwVars []*dwarf.Var) dwarf.InlCalls {
	var inlcalls dwarf.InlCalls

	if base.Debug.DwarfInl != 0 {
		base.Ctxt.Logf("assembling DWARF inlined routine info for %v\n", fnsym.Name)
	}

	// This maps inline index (from Ctxt.InlTree) to index in inlcalls.Calls
	imap := make(map[int]int)

	// Walk progs to build up the InlCalls data structure
	var prevpos src.XPos

					if err != nil {
						return nil
					}
					return dat
				}
			}
			break
		}
	}
	return nil
}

func (f *File) DWARF() (*dwarf.Data, error) {
	// There are many other DWARF sections, but these
	// are the ones the debug/dwarf package uses.
	// Don't bother loading others.
	var subtypes = [...]uint32{SSUBTYP_DWABREV, SSUBTYP_DWINFO, SSUBTYP_DWLINE, SSUBTYP_DWRNGES, SSUBTYP_DWSTR}

		if err != nil {
			return nil, err
		}
		dat[suffix] = b
	}

	d, err := dwarf.New(dat["abbrev"], nil, nil, dat["info"], dat["line"], nil, dat["ranges"], dat["str"])
	if err != nil {
		return nil, err
	}

	// Look for DWARF4 .debug_types sections and DWARF5 sections.
	for i, s := range f.Sections {
		suffix := dwarfSuffix(s)
		if suffix == "" {
			continue
		}

	"cmp",
	"cmd/asm",
	"cmd/asm/internal/...",
	"cmd/cgo",
	"cmd/compile",
	"cmd/compile/internal/...",
	"cmd/internal/archive",
	"cmd/internal/bio",
	"cmd/internal/codesign",
	"cmd/internal/dwarf",
	"cmd/internal/edit",
	"cmd/internal/gcprog",
	"cmd/internal/goobj",
	"cmd/internal/notsha256",
	"cmd/internal/obj/...",
	"cmd/internal/objabi",
	"cmd/internal/pgo",
	"cmd/internal/pkgpath",

	flag.Var(&flagExtld, "extld", "use `linker` when linking in external mode")
	flag.Var(&flagExtldflags, "extldflags", "pass `flags` to external linker")
	flag.Var(&flagW, "w", "disable DWARF generation")
}

// Flags used by the linker. The exported flags are used by the architecture-specific packages.
var (
	flagBuildid = flag.String("buildid", "", "record `id` as Go toolchain build id")

	REG_FT10 = REG_F30
	REG_FT11 = REG_F31

	// Names generated by the SSA compiler.
	REGSP = REG_SP
	REGG  = REG_G
)

// https://github.com/riscv-non-isa/riscv-elf-psabi-doc/blob/master/riscv-dwarf.adoc#dwarf-register-numbers
var RISCV64DWARFRegisters = map[int16]int16{
	// Integer Registers.
	REG_X0:  0,
	REG_X1:  1,
	REG_X2:  2,
	REG_X3:  3,
	REG_X4:  4,
	REG_X5:  5,
	REG_X6:  6,
	REG_X7:  7,

	// For issue 16338: ssa decompose phase split a slice into
	// a collection of scalar vars holding its fields. In such cases
	// the DWARF variable location expression should be of the
	// form "var.field" and not just "field".
	// However, the newer dwarf location list code reconstituted
	// aggregates from their fields and reverted their printing
	// back to its original form.