cmd/link: run generator functions along with symbol writing

Like we do for applying relocations, for generator symbols, run
the generator function along with symbol writing. This will
probably have better locality and parallelism.

Linking cmd/compile,

Asmb          29.9ms ± 5%    19.1ms ±12%  -36.18%  (p=0.000 n=10+9)
TotalTime      351ms ± 3%     339ms ± 2%   -3.51%  (p=0.000 n=11+10)

Change-Id: I9cda6718bf70b3bcf1b7a501a845d6136234d2ee
Reviewed-on: https://go-review.googlesource.com/c/go/+/263640
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>

diff --git a/src/cmd/link/internal/ld/data.go b/src/cmd/link/internal/ld/data.go
index 84e03a4011396f4eb220d8b7d3ff71f297ff3418..00130044abbb9d3a1d9e1f65ca3fa85095f88e6e 100644 (file)
--- a/src/cmd/link/internal/ld/data.go
+++ b/src/cmd/link/internal/ld/data.go
@@ -951,6 +951,9 @@ func writeBlock(ctxt *Link, out *OutBuf, ldr *loader.Loader, syms []loader.Sym,
                }
                P := out.WriteSym(ldr, s)
                st.relocsym(s, P)
+               if f, ok := ctxt.generatorSyms[s]; ok {
+                       f(ctxt, s)
+               }
                addr += int64(len(P))
                siz := ldr.SymSize(s)
                if addr < val+siz {

diff --git a/src/cmd/link/internal/ld/main.go b/src/cmd/link/internal/ld/main.go
index 5ae57d19922183cd8cacbd25954521b7b13e33b3..5c8293810f99fba71d732c4c02e770d493ebc1f1 100644 (file)
--- a/src/cmd/link/internal/ld/main.go
+++ b/src/cmd/link/internal/ld/main.go
@@ -36,14 +36,12 @@ import (
        "cmd/internal/objabi"
        "cmd/internal/sys"
        "cmd/link/internal/benchmark"
-       "cmd/link/internal/loader"
        "flag"
        "log"
        "os"
        "runtime"
        "runtime/pprof"
        "strings"
-       "sync"
 )
 
 var (
@@ -331,16 +329,6 @@ func Main(arch *sys.Arch, theArch Arch) {
        // will be applied directly there.
        bench.Start("Asmb")
        asmb(ctxt)
-       // Generate large symbols.
-       var wg sync.WaitGroup
-       for s, f := range ctxt.generatorSyms {
-               wg.Add(1)
-               go func(f generatorFunc, s loader.Sym) {
-                       defer wg.Done()
-                       f(ctxt, s)
-               }(f, s)
-       }
-       wg.Wait()
 
        // Generate additional symbols for the native symbol table just prior
        // to code generation.