benchcomp: Add macho_symsizes mode for comparing Mach-O object symbol sizes.

llvm-svn: 237199

diff --git a/llgo/utils/benchcomp/main.go b/llgo/utils/benchcomp/main.go
index c7e91c2..433add5 100644 (file)
--- a/llgo/utils/benchcomp/main.go
+++ b/llgo/utils/benchcomp/main.go
@@ -3,8 +3,10 @@ package main
 import (
        "bufio"
        "debug/elf"
+       "debug/macho"
        "fmt"
        "os"
+       "sort"
        "strconv"
        "strings"
 )
@@ -27,6 +29,50 @@ func symsizes(path string) map[string]float64 {
        return m
 }
 
+type bySectionThenOffset []macho.Symbol
+
+func (syms bySectionThenOffset) Len() int {
+       return len(syms)
+}
+
+func (syms bySectionThenOffset) Less(i, j int) bool {
+       if syms[i].Sect < syms[j].Sect {
+               return true
+       }
+       if syms[i].Sect > syms[j].Sect {
+               return false
+       }
+       return syms[i].Value < syms[j].Value
+}
+
+func (syms bySectionThenOffset) Swap(i, j int) {
+       syms[i], syms[j] = syms[j], syms[i]
+}
+
+func macho_symsizes(path string) map[string]float64 {
+       m := make(map[string]float64)
+       f, err := macho.Open(path)
+       if err != nil {
+               panic(err.Error())
+       }
+       syms := make([]macho.Symbol, len(f.Symtab.Syms))
+       copy(syms, f.Symtab.Syms)
+       sort.Sort(bySectionThenOffset(syms))
+       for i, sym := range syms {
+               if sym.Sect == 0 {
+                       continue
+               }
+               var nextOffset uint64
+               if i == len(syms)-1 || syms[i+1].Sect != sym.Sect {
+                       nextOffset = f.Sections[sym.Sect-1].Size
+               } else {
+                       nextOffset = syms[i+1].Value
+               }
+               m[sym.Name] = float64(nextOffset - sym.Value)
+       }
+       return m
+}
+
 func benchnums(path, stat string) map[string]float64 {
        m := make(map[string]float64)
 
@@ -70,6 +116,9 @@ func main() {
        case "symsizes":
                cmp = symsizes
 
+       case "macho_symsizes":
+               cmp = macho_symsizes
+
        case "benchns":
                cmp = func(path string) map[string]float64 {
                        return benchnums(path, "ns/op")