From: Rémy Oudompheng <oudomphe@phare.normalesup.org>
Date: Sat, 14 Sep 2013 07:30:36 +0000 (+0200)
Subject: cmd/gc: don't generate algs for internal map types.
X-Git-Tag: go1.2rc2~219
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=04c40c97c3a76368f878126259fb5d33e0515aaa;p=gostls13.git

cmd/gc: don't generate algs for internal map types.

Fake types describing the internal structure of hashmaps are
generated for use by precise GC.

Generating hash and eq functions for these fake types slows down
the build and wastes space: the go tool binary size is 13MB
instead of 12MB, and the package size on amd64 is 48.7MB instead
of 45.3MB.

R=golang-dev, daniel.morsing, r, khr, rsc, iant
CC=golang-dev
https://golang.org/cl/13698043
---

diff --git a/src/cmd/gc/go.h b/src/cmd/gc/go.h
index ba73508b8f..59e241bbe3 100644
--- a/src/cmd/gc/go.h
+++ b/src/cmd/gc/go.h
@@ -141,6 +141,7 @@ struct	Type
 {
 	uchar	etype;
 	uchar	nointerface;
+	uchar	noalg;
 	uchar	chan;
 	uchar	trecur;		// to detect loops
 	uchar	printed;
diff --git a/src/cmd/gc/reflect.c b/src/cmd/gc/reflect.c
index d204301b59..ea66eb94b2 100644
--- a/src/cmd/gc/reflect.c
+++ b/src/cmd/gc/reflect.c
@@ -131,6 +131,7 @@ mapbucket(Type *t)
 		valtype = ptrto(valtype);
 
 	bucket = typ(TSTRUCT);
+	bucket->noalg = 1;
 
 	// The first field is: uint8 topbits[BUCKETSIZE].
 	// We don't need to encode it as GC doesn't care about it.
@@ -192,6 +193,7 @@ hmap(Type *t)
 
 	bucket = mapbucket(t);
 	h = typ(TSTRUCT);
+	h->noalg = 1;
 
 	offset = widthint; // count
 	offset += 4;       // flags
diff --git a/src/cmd/gc/subr.c b/src/cmd/gc/subr.c
index 3b3b576312..b529e2cc9a 100644
--- a/src/cmd/gc/subr.c
+++ b/src/cmd/gc/subr.c
@@ -547,6 +547,9 @@ algtype1(Type *t, Type **bad)
 	if(bad)
 		*bad = T;
 
+	if(t->noalg)
+		return ANOEQ;
+
 	switch(t->etype) {
 	case TANY:
 	case TFORW: