cmd/compile: refactor gclocals sym creation

It'll be used in second place in a subsequent change. No functional changes. Change-Id: I58dd12d7dde45b36995d031fc7fbb27d6eaf48d3 Reviewed-on: https://go-review.googlesource.com/c/go/+/353670 Trust: Josh Bleecher Snyder <[email protected]> Trust: David Crawshaw <[email protected]> Run-TryBot: Josh Bleecher Snyder <[email protected]> TryBot-Result: Go Bot <[email protected]> Reviewed-by: David Crawshaw <[email protected]>
cloudflare · Oct 4, 2021 · a8d78fa · a8d78fa
1 parent 752cc07
commit a8d78fa
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Showing 2 changed files with 10 additions and 12 deletions.
diff --git a/src/cmd/compile/internal/liveness/plive.go b/src/cmd/compile/internal/liveness/plive.go
@@ -15,7 +15,6 @@
 package liveness
 
 import (
- "crypto/md5"
  "crypto/sha1"
  "fmt"
  "os"
@@ -1326,19 +1325,9 @@ func (lv *liveness) emit() (argsSym, liveSym *obj.LSym) {
  loff = objw.BitVec(&liveSymTmp, loff, locals)
  }
 
- // Give these LSyms content-addressable names,
- // so that they can be de-duplicated.
- // This provides significant binary size savings.
- //
  // These symbols will be added to Ctxt.Data by addGCLocals
  // after parallel compilation is done.
- makeSym := func(tmpSym *obj.LSym) *obj.LSym {
- return base.Ctxt.LookupInit(fmt.Sprintf("gclocals·%x", md5.Sum(tmpSym.P)), func(lsym *obj.LSym) {
- lsym.P = tmpSym.P
- lsym.Set(obj.AttrContentAddressable, true)
- })
- }
- return makeSym(&argsSymTmp), makeSym(&liveSymTmp)
+ return base.Ctxt.GCLocalsSym(argsSymTmp.P), base.Ctxt.GCLocalsSym(liveSymTmp.P)
 }
 
 // Entry pointer for Compute analysis. Solves for the Compute of

diff --git a/src/cmd/internal/obj/sym.go b/src/cmd/internal/obj/sym.go
@@ -34,6 +34,7 @@ package obj
 import (
  "cmd/internal/goobj"
  "cmd/internal/objabi"
+ "crypto/md5"
  "fmt"
  "internal/buildcfg"
  "log"
@@ -172,6 +173,14 @@ func (ctxt *Link) Int64Sym(i int64) *LSym {
  })
 }
 
+// GCLocalsSym generates a content-addressable sym containing data.
+func (ctxt *Link) GCLocalsSym(data []byte) *LSym {
+ return ctxt.LookupInit(fmt.Sprintf("gclocals·%x", md5.Sum(data)), func(lsym *LSym) {
+ lsym.P = data
+ lsym.Set(AttrContentAddressable, true)
+ })
+}
+
 // Assign index to symbols.
 // asm is set to true if this is called by the assembler (i.e. not the compiler),
 // in which case all the symbols are non-package (for now).