debug/elf: don't use reflection in File.Symbols

cpu: AMD Ryzen 9 5950X 16-Core Processor
             |   old.txt    |               new.txt                |
             |    sec/op    |    sec/op     vs base                |
Symbols64-32   18.486µ ± 2%   4.509µ ± 24%  -75.61% (p=0.000 n=10)
Symbols32-32   17.823µ ± 3%   4.798µ ±  2%  -73.08% (p=0.000 n=10)
geomean         18.15µ        4.651µ        -74.38%

             |    old.txt    |               new.txt                |
             |     B/op      |     B/op      vs base                |
Symbols64-32   10.680Ki ± 0%   8.922Ki ± 0%  -16.46% (p=0.000 n=10)
Symbols32-32    9.773Ki ± 0%   8.570Ki ± 0%  -12.31% (p=0.000 n=10)
geomean         10.22Ki        8.744Ki       -14.41%

             |   old.txt   |              new.txt               |
             |  allocs/op  | allocs/op   vs base                |
Symbols64-32   119.00 ± 0%   45.00 ± 0%  -62.18% (p=0.000 n=10)
Symbols32-32   125.00 ± 0%   50.00 ± 0%  -60.00% (p=0.000 n=10)
geomean         122.0        47.43       -61.11%

Fixes #61534

Change-Id: I13a96467108771df31f018853df754e42100e773
Reviewed-on: https://go-review.googlesource.com/c/go/+/512395
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Reviewed-by: David Chase <drchase@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>

2 files changed, 311 insertions, 14 deletions

diff --git a/src/debug/elf/file.go b/src/debug/elf/file.go
index 7485337905..9416ddaefb 100644
--- a/src/debug/elf/file.go
+++ b/src/debug/elf/file.go
@@ -639,8 +639,7 @@ func (f *File) getSymbols32(typ SectionType) ([]Symbol, []byte, error) {
 	if err != nil {
 		return nil, nil, fmt.Errorf("cannot load symbol section: %w", err)
 	}
-	symtab := bytes.NewReader(data)
-	if symtab.Len()%Sym32Size != 0 {
+	if len(data)%Sym32Size != 0 {
 		return nil, nil, errors.New("length of symbol section is not a multiple of SymSize")
 	}
 
@@ -650,15 +649,19 @@ func (f *File) getSymbols32(typ SectionType) ([]Symbol, []byte, error) {
 	}
 
 	// The first entry is all zeros.
-	var skip [Sym32Size]byte
-	symtab.Read(skip[:])
+	data = data[Sym32Size:]
 
-	symbols := make([]Symbol, symtab.Len()/Sym32Size)
+	symbols := make([]Symbol, len(data)/Sym32Size)
 
 	i := 0
 	var sym Sym32
-	for symtab.Len() > 0 {
-		binary.Read(symtab, f.ByteOrder, &sym)
+	for len(data) > 0 {
+		sym.Name = f.ByteOrder.Uint32(data[0:4])
+		sym.Value = f.ByteOrder.Uint32(data[4:8])
+		sym.Size = f.ByteOrder.Uint32(data[8:12])
+		sym.Info = data[12]
+		sym.Other = data[13]
+		sym.Shndx = f.ByteOrder.Uint16(data[14:16])
 		str, _ := getString(strdata, int(sym.Name))
 		symbols[i].Name = str
 		symbols[i].Info = sym.Info
@@ -667,6 +670,7 @@ func (f *File) getSymbols32(typ SectionType) ([]Symbol, []byte, error) {
 		symbols[i].Value = uint64(sym.Value)
 		symbols[i].Size = uint64(sym.Size)
 		i++
+		data = data[Sym32Size:]
 	}
 
 	return symbols, strdata, nil
@@ -682,8 +686,7 @@ func (f *File) getSymbols64(typ SectionType) ([]Symbol, []byte, error) {
 	if err != nil {
 		return nil, nil, fmt.Errorf("cannot load symbol section: %w", err)
 	}
-	symtab := bytes.NewReader(data)
-	if symtab.Len()%Sym64Size != 0 {
+	if len(data)%Sym64Size != 0 {
 		return nil, nil, errors.New("length of symbol section is not a multiple of Sym64Size")
 	}
 
@@ -693,15 +696,19 @@ func (f *File) getSymbols64(typ SectionType) ([]Symbol, []byte, error) {
 	}
 
 	// The first entry is all zeros.
-	var skip [Sym64Size]byte
-	symtab.Read(skip[:])
+	data = data[Sym64Size:]
 
-	symbols := make([]Symbol, symtab.Len()/Sym64Size)
+	symbols := make([]Symbol, len(data)/Sym64Size)
 
 	i := 0
 	var sym Sym64
-	for symtab.Len() > 0 {
-		binary.Read(symtab, f.ByteOrder, &sym)
+	for len(data) > 0 {
+		sym.Name = f.ByteOrder.Uint32(data[0:4])
+		sym.Info = data[4]
+		sym.Other = data[5]
+		sym.Shndx = f.ByteOrder.Uint16(data[6:8])
+		sym.Value = f.ByteOrder.Uint64(data[8:16])
+		sym.Size = f.ByteOrder.Uint64(data[16:24])
 		str, _ := getString(strdata, int(sym.Name))
 		symbols[i].Name = str
 		symbols[i].Info = sym.Info
@@ -710,6 +717,7 @@ func (f *File) getSymbols64(typ SectionType) ([]Symbol, []byte, error) {
 		symbols[i].Value = sym.Value
 		symbols[i].Size = sym.Size
 		i++
+		data = data[Sym64Size:]
 	}
 
 	return symbols, strdata, nil
diff --git a/src/debug/elf/file_test.go b/src/debug/elf/file_test.go
index 51a3634db9..f9b3ce3121 100644
--- a/src/debug/elf/file_test.go
+++ b/src/debug/elf/file_test.go
@@ -10,6 +10,7 @@ import (
 	"compress/zlib"
 	"debug/dwarf"
 	"encoding/binary"
+	"errors"
 	"fmt"
 	"io"
 	"math/rand"
@@ -18,6 +19,7 @@ import (
 	"path"
 	"reflect"
 	"runtime"
+	"slices"
 	"strings"
 	"testing"
 )
@@ -28,6 +30,7 @@ type fileTest struct {
 	sections []SectionHeader
 	progs    []ProgHeader
 	needed   []string
+	symbols  []Symbol
 }
 
 var fileTests = []fileTest{
@@ -74,6 +77,82 @@ var fileTests = []fileTest{
 			{PT_DYNAMIC, PF_R + PF_W, 0x60c, 0x804960c, 0x804960c, 0x98, 0x98, 0x4},
 		},
 		[]string{"libc.so.6"},
+		[]Symbol{
+			{"", 3, 0, 1, 134512852, 0, "", ""},
+			{"", 3, 0, 2, 134512876, 0, "", ""},
+			{"", 3, 0, 3, 134513020, 0, "", ""},
+			{"", 3, 0, 4, 134513292, 0, "", ""},
+			{"", 3, 0, 5, 134513480, 0, "", ""},
+			{"", 3, 0, 6, 134513512, 0, "", ""},
+			{"", 3, 0, 7, 134513532, 0, "", ""},
+			{"", 3, 0, 8, 134513612, 0, "", ""},
+			{"", 3, 0, 9, 134513996, 0, "", ""},
+			{"", 3, 0, 10, 134514008, 0, "", ""},
+			{"", 3, 0, 11, 134518268, 0, "", ""},
+			{"", 3, 0, 12, 134518280, 0, "", ""},
+			{"", 3, 0, 13, 134518284, 0, "", ""},
+			{"", 3, 0, 14, 134518436, 0, "", ""},
+			{"", 3, 0, 15, 134518444, 0, "", ""},
+			{"", 3, 0, 16, 134518452, 0, "", ""},
+			{"", 3, 0, 17, 134518456, 0, "", ""},
+			{"", 3, 0, 18, 134518484, 0, "", ""},
+			{"", 3, 0, 19, 0, 0, "", ""},
+			{"", 3, 0, 20, 0, 0, "", ""},
+			{"", 3, 0, 21, 0, 0, "", ""},
+			{"", 3, 0, 22, 0, 0, "", ""},
+			{"", 3, 0, 23, 0, 0, "", ""},
+			{"", 3, 0, 24, 0, 0, "", ""},
+			{"", 3, 0, 25, 0, 0, "", ""},
+			{"", 3, 0, 26, 0, 0, "", ""},
+			{"", 3, 0, 27, 0, 0, "", ""},
+			{"", 3, 0, 28, 0, 0, "", ""},
+			{"", 3, 0, 29, 0, 0, "", ""},
+			{"crt1.c", 4, 0, 65521, 0, 0, "", ""},
+			{"/usr/src/lib/csu/i386-elf/crti.S", 4, 0, 65521, 0, 0, "", ""},
+			{"<command line>", 4, 0, 65521, 0, 0, "", ""},
+			{"<built-in>", 4, 0, 65521, 0, 0, "", ""},
+			{"/usr/src/lib/csu/i386-elf/crti.S", 4, 0, 65521, 0, 0, "", ""},
+			{"crtstuff.c", 4, 0, 65521, 0, 0, "", ""},
+			{"__CTOR_LIST__", 1, 0, 14, 134518436, 0, "", ""},
+			{"__DTOR_LIST__", 1, 0, 15, 134518444, 0, "", ""},
+			{"__EH_FRAME_BEGIN__", 1, 0, 12, 134518280, 0, "", ""},
+			{"__JCR_LIST__", 1, 0, 16, 134518452, 0, "", ""},
+			{"p.0", 1, 0, 11, 134518276, 0, "", ""},
+			{"completed.1", 1, 0, 18, 134518484, 1, "", ""},
+			{"__do_global_dtors_aux", 2, 0, 8, 134513760, 0, "", ""},
+			{"object.2", 1, 0, 18, 134518488, 24, "", ""},
+			{"frame_dummy", 2, 0, 8, 134513836, 0, "", ""},
+			{"crtstuff.c", 4, 0, 65521, 0, 0, "", ""},
+			{"__CTOR_END__", 1, 0, 14, 134518440, 0, "", ""},
+			{"__DTOR_END__", 1, 0, 15, 134518448, 0, "", ""},
+			{"__FRAME_END__", 1, 0, 12, 134518280, 0, "", ""},
+			{"__JCR_END__", 1, 0, 16, 134518452, 0, "", ""},
+			{"__do_global_ctors_aux", 2, 0, 8, 134513960, 0, "", ""},
+			{"/usr/src/lib/csu/i386-elf/crtn.S", 4, 0, 65521, 0, 0, "", ""},
+			{"<command line>", 4, 0, 65521, 0, 0, "", ""},
+			{"<built-in>", 4, 0, 65521, 0, 0, "", ""},
+			{"/usr/src/lib/csu/i386-elf/crtn.S", 4, 0, 65521, 0, 0, "", ""},
+			{"hello.c", 4, 0, 65521, 0, 0, "", ""},
+			{"printf", 18, 0, 0, 0, 44, "", ""},
+			{"_DYNAMIC", 17, 0, 65521, 134518284, 0, "", ""},
+			{"__dso_handle", 17, 2, 11, 134518272, 0, "", ""},
+			{"_init", 18, 0, 6, 134513512, 0, "", ""},
+			{"environ", 17, 0, 18, 134518512, 4, "", ""},
+			{"__deregister_frame_info", 32, 0, 0, 0, 0, "", ""},
+			{"__progname", 17, 0, 11, 134518268, 4, "", ""},
+			{"_start", 18, 0, 8, 134513612, 145, "", ""},
+			{"__bss_start", 16, 0, 65521, 134518484, 0, "", ""},
+			{"main", 18, 0, 8, 134513912, 46, "", ""},
+			{"_init_tls", 18, 0, 0, 0, 5, "", ""},
+			{"_fini", 18, 0, 9, 134513996, 0, "", ""},
+			{"atexit", 18, 0, 0, 0, 43, "", ""},
+			{"_edata", 16, 0, 65521, 134518484, 0, "", ""},
+			{"_GLOBAL_OFFSET_TABLE_", 17, 0, 65521, 134518456, 0, "", ""},
+			{"_end", 16, 0, 65521, 134518516, 0, "", ""},
+			{"exit", 18, 0, 0, 0, 68, "", ""},
+			{"_Jv_RegisterClasses", 32, 0, 0, 0, 0, "", ""},
+			{"__register_frame_info", 32, 0, 0, 0, 0, "", ""},
+		},
 	},
 	{
 		"testdata/gcc-amd64-linux-exec",
@@ -128,6 +207,81 @@ var fileTests = []fileTest{
 			{PT_LOOS + 0x474E551, PF_R + PF_W, 0x0, 0x0, 0x0, 0x0, 0x0, 0x8},
 		},
 		[]string{"libc.so.6"},
+		[]Symbol{
+			{"", 3, 0, 1, 4194816, 0, "", ""},
+			{"", 3, 0, 2, 4194844, 0, "", ""},
+			{"", 3, 0, 3, 4194880, 0, "", ""},
+			{"", 3, 0, 4, 4194920, 0, "", ""},
+			{"", 3, 0, 5, 4194952, 0, "", ""},
+			{"", 3, 0, 6, 4195048, 0, "", ""},
+			{"", 3, 0, 7, 4195110, 0, "", ""},
+			{"", 3, 0, 8, 4195120, 0, "", ""},
+			{"", 3, 0, 9, 4195152, 0, "", ""},
+			{"", 3, 0, 10, 4195176, 0, "", ""},
+			{"", 3, 0, 11, 4195224, 0, "", ""},
+			{"", 3, 0, 12, 4195248, 0, "", ""},
+			{"", 3, 0, 13, 4195296, 0, "", ""},
+			{"", 3, 0, 14, 4195732, 0, "", ""},
+			{"", 3, 0, 15, 4195748, 0, "", ""},
+			{"", 3, 0, 16, 4195768, 0, "", ""},
+			{"", 3, 0, 17, 4195808, 0, "", ""},
+			{"", 3, 0, 18, 6293128, 0, "", ""},
+			{"", 3, 0, 19, 6293144, 0, "", ""},
+			{"", 3, 0, 20, 6293160, 0, "", ""},
+			{"", 3, 0, 21, 6293168, 0, "", ""},
+			{"", 3, 0, 22, 6293584, 0, "", ""},
+			{"", 3, 0, 23, 6293592, 0, "", ""},
+			{"", 3, 0, 24, 6293632, 0, "", ""},
+			{"", 3, 0, 25, 6293656, 0, "", ""},
+			{"", 3, 0, 26, 0, 0, "", ""},
+			{"", 3, 0, 27, 0, 0, "", ""},
+			{"", 3, 0, 28, 0, 0, "", ""},
+			{"", 3, 0, 29, 0, 0, "", ""},
+			{"", 3, 0, 30, 0, 0, "", ""},
+			{"", 3, 0, 31, 0, 0, "", ""},
+			{"", 3, 0, 32, 0, 0, "", ""},
+			{"", 3, 0, 33, 0, 0, "", ""},
+			{"init.c", 4, 0, 65521, 0, 0, "", ""},
+			{"initfini.c", 4, 0, 65521, 0, 0, "", ""},
+			{"call_gmon_start", 2, 0, 13, 4195340, 0, "", ""},
+			{"crtstuff.c", 4, 0, 65521, 0, 0, "", ""},
+			{"__CTOR_LIST__", 1, 0, 18, 6293128, 0, "", ""},
+			{"__DTOR_LIST__", 1, 0, 19, 6293144, 0, "", ""},
+			{"__JCR_LIST__", 1, 0, 20, 6293160, 0, "", ""},
+			{"__do_global_dtors_aux", 2, 0, 13, 4195376, 0, "", ""},
+			{"completed.6183", 1, 0, 25, 6293656, 1, "", ""},
+			{"p.6181", 1, 0, 24, 6293648, 0, "", ""},
+			{"frame_dummy", 2, 0, 13, 4195440, 0, "", ""},
+			{"crtstuff.c", 4, 0, 65521, 0, 0, "", ""},
+			{"__CTOR_END__", 1, 0, 18, 6293136, 0, "", ""},
+			{"__DTOR_END__", 1, 0, 19, 6293152, 0, "", ""},
+			{"__FRAME_END__", 1, 0, 17, 4195968, 0, "", ""},
+			{"__JCR_END__", 1, 0, 20, 6293160, 0, "", ""},
+			{"__do_global_ctors_aux", 2, 0, 13, 4195680, 0, "", ""},
+			{"initfini.c", 4, 0, 65521, 0, 0, "", ""},
+			{"hello.c", 4, 0, 65521, 0, 0, "", ""},
+			{"_GLOBAL_OFFSET_TABLE_", 1, 2, 23, 6293592, 0, "", ""},
+			{"__init_array_end", 0, 2, 18, 6293124, 0, "", ""},
+			{"__init_array_start", 0, 2, 18, 6293124, 0, "", ""},
+			{"_DYNAMIC", 1, 2, 21, 6293168, 0, "", ""},
+			{"data_start", 32, 0, 24, 6293632, 0, "", ""},
+			{"__libc_csu_fini", 18, 0, 13, 4195520, 2, "", ""},
+			{"_start", 18, 0, 13, 4195296, 0, "", ""},
+			{"__gmon_start__", 32, 0, 0, 0, 0, "", ""},
+			{"_Jv_RegisterClasses", 32, 0, 0, 0, 0, "", ""},
+			{"puts@@GLIBC_2.2.5", 18, 0, 0, 0, 396, "", ""},
+			{"_fini", 18, 0, 14, 4195732, 0, "", ""},
+			{"__libc_start_main@@GLIBC_2.2.5", 18, 0, 0, 0, 450, "", ""},
+			{"_IO_stdin_used", 17, 0, 15, 4195748, 4, "", ""},
+			{"__data_start", 16, 0, 24, 6293632, 0, "", ""},
+			{"__dso_handle", 17, 2, 24, 6293640, 0, "", ""},
+			{"__libc_csu_init", 18, 0, 13, 4195536, 137, "", ""},
+			{"__bss_start", 16, 0, 65521, 6293656, 0, "", ""},
+			{"_end", 16, 0, 65521, 6293664, 0, "", ""},
+			{"_edata", 16, 0, 65521, 6293656, 0, "", ""},
+			{"main", 18, 0, 13, 4195480, 27, "", ""},
+			{"_init", 18, 0, 11, 4195224, 0, "", ""},
+		},
 	},
 	{
 		"testdata/hello-world-core.gz",
@@ -153,6 +307,7 @@ var fileTests = []fileTest{
 			{Type: PT_LOAD, Flags: PF_X + PF_R, Off: 0x3b000, Vaddr: 0xffffffffff600000, Paddr: 0x0, Filesz: 0x1000, Memsz: 0x1000, Align: 0x1000},
 		},
 		nil,
+		nil,
 	},
 	{
 		"testdata/compressed-32.obj",
@@ -182,6 +337,23 @@ var fileTests = []fileTest{
 		},
 		[]ProgHeader{},
 		nil,
+		[]Symbol{
+			{"hello.c", 4, 0, 65521, 0, 0, "", ""},
+			{"", 3, 0, 1, 0, 0, "", ""},
+			{"", 3, 0, 3, 0, 0, "", ""},
+			{"", 3, 0, 4, 0, 0, "", ""},
+			{"", 3, 0, 5, 0, 0, "", ""},
+			{"", 3, 0, 6, 0, 0, "", ""},
+			{"", 3, 0, 8, 0, 0, "", ""},
+			{"", 3, 0, 9, 0, 0, "", ""},
+			{"", 3, 0, 11, 0, 0, "", ""},
+			{"", 3, 0, 13, 0, 0, "", ""},
+			{"", 3, 0, 15, 0, 0, "", ""},
+			{"", 3, 0, 16, 0, 0, "", ""},
+			{"", 3, 0, 14, 0, 0, "", ""},
+			{"main", 18, 0, 1, 0, 23, "", ""},
+			{"puts", 16, 0, 0, 0, 0, "", ""},
+		},
 	},
 	{
 		"testdata/compressed-64.obj",
@@ -211,6 +383,69 @@ var fileTests = []fileTest{
 		},
 		[]ProgHeader{},
 		nil,
+		[]Symbol{
+			{"hello.c", 4, 0, 65521, 0, 0, "", ""},
+			{"", 3, 0, 1, 0, 0, "", ""},
+			{"", 3, 0, 3, 0, 0, "", ""},
+			{"", 3, 0, 4, 0, 0, "", ""},
+			{"", 3, 0, 5, 0, 0, "", ""},
+			{"", 3, 0, 6, 0, 0, "", ""},
+			{"", 3, 0, 8, 0, 0, "", ""},
+			{"", 3, 0, 9, 0, 0, "", ""},
+			{"", 3, 0, 11, 0, 0, "", ""},
+			{"", 3, 0, 13, 0, 0, "", ""},
+			{"", 3, 0, 15, 0, 0, "", ""},
+			{"", 3, 0, 16, 0, 0, "", ""},
+			{"", 3, 0, 14, 0, 0, "", ""},
+			{"main", 18, 0, 1, 0, 27, "", ""},
+			{"puts", 16, 0, 0, 0, 0, "", ""},
+		},
+	},
+	{
+		"testdata/go-relocation-test-gcc620-sparc64.obj",
+		FileHeader{Class: ELFCLASS64, Data: ELFDATA2MSB, Version: EV_CURRENT, OSABI: ELFOSABI_NONE, ABIVersion: 0x0, ByteOrder: binary.BigEndian, Type: ET_REL, Machine: EM_SPARCV9, Entry: 0x0},
+		[]SectionHeader{
+			{"", SHT_NULL, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0},
+			{".text", SHT_PROGBITS, SHF_ALLOC + SHF_EXECINSTR, 0x0, 0x40, 0x2c, 0x0, 0x0, 0x4, 0x0, 0x2c},
+			{".rela.text", SHT_RELA, SHF_INFO_LINK, 0x0, 0xa58, 0x48, 0x13, 0x1, 0x8, 0x18, 0x48},
+			{".data", SHT_PROGBITS, SHF_WRITE + SHF_ALLOC, 0x0, 0x6c, 0x0, 0x0, 0x0, 0x1, 0x0, 0x0},
+			{".bss", SHT_NOBITS, SHF_WRITE + SHF_ALLOC, 0x0, 0x6c, 0x0, 0x0, 0x0, 0x1, 0x0, 0x0},
+			{".rodata", SHT_PROGBITS, SHF_ALLOC, 0x0, 0x70, 0xd, 0x0, 0x0, 0x8, 0x0, 0xd},
+			{".debug_info", SHT_PROGBITS, 0x0, 0x0, 0x7d, 0x346, 0x0, 0x0, 0x1, 0x0, 0x346},
+			{".rela.debug_info", SHT_RELA, SHF_INFO_LINK, 0x0, 0xaa0, 0x630, 0x13, 0x6, 0x8, 0x18, 0x630},
+			{".debug_abbrev", SHT_PROGBITS, 0x0, 0x0, 0x3c3, 0xf1, 0x0, 0x0, 0x1, 0x0, 0xf1},
+			{".debug_aranges", SHT_PROGBITS, 0x0, 0x0, 0x4b4, 0x30, 0x0, 0x0, 0x1, 0x0, 0x30},
+			{".rela.debug_aranges", SHT_RELA, SHF_INFO_LINK, 0x0, 0x10d0, 0x30, 0x13, 0x9, 0x8, 0x18, 0x30},
+			{".debug_line", SHT_PROGBITS, 0x0, 0x0, 0x4e4, 0xd3, 0x0, 0x0, 0x1, 0x0, 0xd3},
+			{".rela.debug_line", SHT_RELA, SHF_INFO_LINK, 0x0, 0x1100, 0x18, 0x13, 0xb, 0x8, 0x18, 0x18},
+			{".debug_str", SHT_PROGBITS, SHF_MERGE + SHF_STRINGS, 0x0, 0x5b7, 0x2a3, 0x0, 0x0, 0x1, 0x1, 0x2a3},
+			{".comment", SHT_PROGBITS, SHF_MERGE + SHF_STRINGS, 0x0, 0x85a, 0x2e, 0x0, 0x0, 0x1, 0x1, 0x2e},
+			{".note.GNU-stack", SHT_PROGBITS, 0x0, 0x0, 0x888, 0x0, 0x0, 0x0, 0x1, 0x0, 0x0},
+			{".debug_frame", SHT_PROGBITS, 0x0, 0x0, 0x888, 0x38, 0x0, 0x0, 0x8, 0x0, 0x38},
+			{".rela.debug_frame", SHT_RELA, SHF_INFO_LINK, 0x0, 0x1118, 0x30, 0x13, 0x10, 0x8, 0x18, 0x30},
+			{".shstrtab", SHT_STRTAB, 0x0, 0x0, 0x1148, 0xb3, 0x0, 0x0, 0x1, 0x0, 0xb3},
+			{".symtab", SHT_SYMTAB, 0x0, 0x0, 0x8c0, 0x180, 0x14, 0xe, 0x8, 0x18, 0x180},
+			{".strtab", SHT_STRTAB, 0x0, 0x0, 0xa40, 0x13, 0x0, 0x0, 0x1, 0x0, 0x13},
+		},
+		[]ProgHeader{},
+		nil,
+		[]Symbol{
+			{"hello.c", 4, 0, 65521, 0, 0, "", ""},
+			{"", 3, 0, 1, 0, 0, "", ""},
+			{"", 3, 0, 3, 0, 0, "", ""},
+			{"", 3, 0, 4, 0, 0, "", ""},
+			{"", 3, 0, 5, 0, 0, "", ""},
+			{"", 3, 0, 6, 0, 0, "", ""},
+			{"", 3, 0, 8, 0, 0, "", ""},
+			{"", 3, 0, 9, 0, 0, "", ""},
+			{"", 3, 0, 11, 0, 0, "", ""},
+			{"", 3, 0, 13, 0, 0, "", ""},
+			{"", 3, 0, 15, 0, 0, "", ""},
+			{"", 3, 0, 16, 0, 0, "", ""},
+			{"", 3, 0, 14, 0, 0, "", ""},
+			{"main", 18, 0, 1, 0, 44, "", ""},
+			{"puts", 16, 0, 0, 0, 0, "", ""},
+		},
 	},
 }
 
@@ -273,6 +508,22 @@ func TestOpen(t *testing.T) {
 		if !reflect.DeepEqual(tl, fl) {
 			t.Errorf("open %s: DT_NEEDED = %v, want %v", tt.file, tl, fl)
 		}
+		symbols, err := f.Symbols()
+		if tt.symbols == nil {
+			if !errors.Is(err, ErrNoSymbols) {
+				t.Errorf("open %s: Symbols() expected ErrNoSymbols, have nil", tt.file)
+			}
+			if symbols != nil {
+				t.Errorf("open %s: Symbols() expected no symbols, have %v", tt.file, symbols)
+			}
+		} else {
+			if err != nil {
+				t.Errorf("open %s: Symbols() unexpected error %v", tt.file, err)
+			}
+			if !slices.Equal(symbols, tt.symbols) {
+				t.Errorf("open %s: Symbols() = %v, want %v", tt.file, symbols, tt.symbols)
+			}
+		}
 	}
 }
 
@@ -1288,3 +1539,41 @@ func TestIssue59208(t *testing.T) {
 		t.Errorf("DWARF = %v; want %q", err, want)
 	}
 }
+
+func BenchmarkSymbols64(b *testing.B) {
+	const testdata = "testdata/gcc-amd64-linux-exec"
+	f, err := Open(testdata)
+	if err != nil {
+		b.Fatalf("could not read %s: %v", testdata, err)
+	}
+	defer f.Close()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		symbols, err := f.Symbols()
+		if err != nil {
+			b.Fatalf("Symbols(): got unexpected error %v", err)
+		}
+		if len(symbols) != 73 {
+			b.Errorf("\nhave %d symbols\nwant %d symbols\n", len(symbols), 73)
+		}
+	}
+}
+
+func BenchmarkSymbols32(b *testing.B) {
+	const testdata = "testdata/gcc-386-freebsd-exec"
+	f, err := Open(testdata)
+	if err != nil {
+		b.Fatalf("could not read %s: %v", testdata, err)
+	}
+	defer f.Close()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		symbols, err := f.Symbols()
+		if err != nil {
+			b.Fatalf("Symbols(): got unexpected error %v", err)
+		}
+		if len(symbols) != 74 {
+			b.Errorf("\nhave %d symbols\nwant %d symbols\n", len(symbols), 74)
+		}
+	}
+}