[dev.garbage] all: merge dev.cc (81884b89bd88) into dev.garbage

TBR=rlh
CC=golang-codereviews
https://codereview.appspot.com/181100044

7 files changed, 123 insertions, 16 deletions

diff --git a/src/cmd/api/goapi.go b/src/cmd/api/goapi.go
index 5a8c87603..e49ba33bb 100644
--- a/src/cmd/api/goapi.go
+++ b/src/cmd/api/goapi.go
@@ -405,6 +405,7 @@ func (w *Walker) parseFile(dir, file string) (*ast.File, error) {
 			" note struct{};" +
 			" p struct{};" +
 			" parfor struct{};" +
+			" slice struct{};" +
 			" slicetype struct{};" +
 			" stkframe struct{};" +
 			" sudog struct{};" +
diff --git a/src/cmd/gc/builtin.c b/src/cmd/gc/builtin.c
index fbca4ee5f..aeeadedca 100644
--- a/src/cmd/gc/builtin.c
+++ b/src/cmd/gc/builtin.c
@@ -24,6 +24,8 @@ char *runtimeimport =
 	"func @\"\".printslice (? any)\n"
 	"func @\"\".printnl ()\n"
 	"func @\"\".printsp ()\n"
+	"func @\"\".printlock ()\n"
+	"func @\"\".printunlock ()\n"
 	"func @\"\".concatstring2 (? string, ? string) (? string)\n"
 	"func @\"\".concatstring3 (? string, ? string, ? string) (? string)\n"
 	"func @\"\".concatstring4 (? string, ? string, ? string, ? string) (? string)\n"
@@ -86,10 +88,33 @@ char *runtimeimport =
 	"func @\"\".writebarrierstring (@\"\".dst·1 *any, @\"\".src·2 any)\n"
 	"func @\"\".writebarrierslice (@\"\".dst·1 *any, @\"\".src·2 any)\n"
 	"func @\"\".writebarrieriface (@\"\".dst·1 *any, @\"\".src·2 any)\n"
-	"func @\"\".writebarrierfat2 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
-	"func @\"\".writebarrierfat3 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
-	"func @\"\".writebarrierfat4 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat01 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat10 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat11 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat001 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat010 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat011 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat100 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat101 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat110 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat111 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat0001 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat0010 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat0011 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat0100 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat0101 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat0110 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat0111 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat1000 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat1001 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat1010 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat1011 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat1100 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat1101 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat1110 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
+	"func @\"\".writebarrierfat1111 (@\"\".dst·1 *any, _ *byte, @\"\".src·3 any)\n"
 	"func @\"\".writebarrierfat (@\"\".typ·1 *byte, @\"\".dst·2 *any, @\"\".src·3 *any)\n"
+	"func @\"\".writebarriercopy (@\"\".typ·2 *byte, @\"\".dst·3 any, @\"\".src·4 any) (? int)\n"
 	"func @\"\".selectnbsend (@\"\".chanType·2 *byte, @\"\".hchan·3 chan<- any, @\"\".elem·4 *any) (? bool)\n"
 	"func @\"\".selectnbrecv (@\"\".chanType·2 *byte, @\"\".elem·3 *any, @\"\".hchan·4 <-chan any) (? bool)\n"
 	"func @\"\".selectnbrecv2 (@\"\".chanType·2 *byte, @\"\".elem·3 *any, @\"\".received·4 *bool, @\"\".hchan·5 <-chan any) (? bool)\n"
diff --git a/src/cmd/gc/go.h b/src/cmd/gc/go.h
index 6e326961d..5236305f8 100644
--- a/src/cmd/gc/go.h
+++ b/src/cmd/gc/go.h
@@ -1473,6 +1473,7 @@ void	walk(Node *fn);
 void	walkexpr(Node **np, NodeList **init);
 void	walkexprlist(NodeList *l, NodeList **init);
 void	walkexprlistsafe(NodeList *l, NodeList **init);
+void	walkexprlistcheap(NodeList *l, NodeList **init);
 void	walkstmt(Node **np);
 void	walkstmtlist(NodeList *l);
 Node*	conv(Node*, Type*);
diff --git a/src/cmd/gc/popt.c b/src/cmd/gc/popt.c
index 993bb2482..6e6db88ef 100644
--- a/src/cmd/gc/popt.c
+++ b/src/cmd/gc/popt.c
@@ -847,6 +847,10 @@ nilopt(Prog *firstp)
 	Graph *g;
 	int ncheck, nkill;
 
+	// TODO(minux): nilopt on power64 throw away seemly random segment of code.
+	if(thechar == '9')
+		return;
+
 	g = flowstart(firstp, sizeof(NilFlow));
 	if(g == nil)
 		return;
diff --git a/src/cmd/gc/runtime.go b/src/cmd/gc/runtime.go
index 0fb15c265..c6007714c 100644
--- a/src/cmd/gc/runtime.go
+++ b/src/cmd/gc/runtime.go
@@ -36,6 +36,8 @@ func printeface(any)
 func printslice(any)
 func printnl()
 func printsp()
+func printlock()
+func printunlock()
 
 func concatstring2(string, string) string
 func concatstring3(string, string, string) string
@@ -115,10 +117,35 @@ func writebarrieriface(dst *any, src any)
 // The unused *byte argument makes sure that src is 2-pointer-aligned,
 // which is the maximum alignment on NaCl amd64p32
 // (and possibly on 32-bit systems if we start 64-bit aligning uint64s).
-func writebarrierfat2(dst *any, _ *byte, src any)
-func writebarrierfat3(dst *any, _ *byte, src any)
-func writebarrierfat4(dst *any, _ *byte, src any)
+// The bitmap in the name tells which words being copied are pointers.
+func writebarrierfat01(dst *any, _ *byte, src any)
+func writebarrierfat10(dst *any, _ *byte, src any)
+func writebarrierfat11(dst *any, _ *byte, src any)
+func writebarrierfat001(dst *any, _ *byte, src any)
+func writebarrierfat010(dst *any, _ *byte, src any)
+func writebarrierfat011(dst *any, _ *byte, src any)
+func writebarrierfat100(dst *any, _ *byte, src any)
+func writebarrierfat101(dst *any, _ *byte, src any)
+func writebarrierfat110(dst *any, _ *byte, src any)
+func writebarrierfat111(dst *any, _ *byte, src any)
+func writebarrierfat0001(dst *any, _ *byte, src any)
+func writebarrierfat0010(dst *any, _ *byte, src any)
+func writebarrierfat0011(dst *any, _ *byte, src any)
+func writebarrierfat0100(dst *any, _ *byte, src any)
+func writebarrierfat0101(dst *any, _ *byte, src any)
+func writebarrierfat0110(dst *any, _ *byte, src any)
+func writebarrierfat0111(dst *any, _ *byte, src any)
+func writebarrierfat1000(dst *any, _ *byte, src any)
+func writebarrierfat1001(dst *any, _ *byte, src any)
+func writebarrierfat1010(dst *any, _ *byte, src any)
+func writebarrierfat1011(dst *any, _ *byte, src any)
+func writebarrierfat1100(dst *any, _ *byte, src any)
+func writebarrierfat1101(dst *any, _ *byte, src any)
+func writebarrierfat1110(dst *any, _ *byte, src any)
+func writebarrierfat1111(dst *any, _ *byte, src any)
+
 func writebarrierfat(typ *byte, dst *any, src *any)
+func writebarriercopy(typ *byte, dst any, src any) int
 
 func selectnbsend(chanType *byte, hchan chan<- any, elem *any) bool
 func selectnbrecv(chanType *byte, elem *any, hchan <-chan any) bool
diff --git a/src/cmd/gc/typecheck.c b/src/cmd/gc/typecheck.c
index 714c66268..f05d8022d 100644
--- a/src/cmd/gc/typecheck.c
+++ b/src/cmd/gc/typecheck.c
@@ -2891,7 +2891,8 @@ typecheckas(Node *n)
 		case OSLICE3:
 		case OSLICESTR:
 			// For x = x[0:y], x can be updated in place, without touching pointer.
-			if(samesafeexpr(n->left, n->right->left) && (n->right->right->left == N || iszero(n->right->right->left)))
+			// TODO(rsc): Reenable once it is actually updated in place without touching the pointer.
+			if(0 && samesafeexpr(n->left, n->right->left) && (n->right->right->left == N || iszero(n->right->right->left)))
 				n->right->reslice = 1;
 			break;
 		
@@ -2899,7 +2900,8 @@ typecheckas(Node *n)
 			// For x = append(x, ...), x can be updated in place when there is capacity,
 			// without touching the pointer; otherwise the emitted code to growslice
 			// can take care of updating the pointer, and only in that case.
-			if(n->right->list != nil && samesafeexpr(n->left, n->right->list->n))
+			// TODO(rsc): Reenable once the emitted code does update the pointer.
+			if(0 && n->right->list != nil && samesafeexpr(n->left, n->right->list->n))
 				n->right->reslice = 1;
 			break;
 		}
diff --git a/src/cmd/gc/walk.c b/src/cmd/gc/walk.c
index 77f9c80f9..061089349 100644
--- a/src/cmd/gc/walk.c
+++ b/src/cmd/gc/walk.c
@@ -6,6 +6,7 @@
 #include	<libc.h>
 #include	"go.h"
 #include	"../ld/textflag.h"
+#include	"../../runtime/mgc0.h"
 
 static	Node*	walkprint(Node*, NodeList**);
 static	Node*	writebarrierfn(char*, Type*, Type*);
@@ -363,6 +364,15 @@ walkexprlistsafe(NodeList *l, NodeList **init)
 }
 
 void
+walkexprlistcheap(NodeList *l, NodeList **init)
+{
+	for(; l; l=l->next) {
+		l->n = cheapexpr(l->n, init);
+		walkexpr(&l->n, init);
+	}
+}
+
+void
 walkexpr(Node **np, NodeList **init)
 {
 	Node *r, *l, *var, *a;
@@ -1771,6 +1781,11 @@ walkprint(Node *nn, NodeList **init)
 	calls = nil;
 	notfirst = 0;
 
+	// Hoist all the argument evaluation up before the lock.
+	walkexprlistcheap(all, init);
+
+	calls = list(calls, mkcall("printlock", T, init));
+
 	for(l=all; l; l=l->next) {
 		if(notfirst) {
 			calls = list(calls, mkcall("printsp", T, init));
@@ -1851,6 +1866,9 @@ walkprint(Node *nn, NodeList **init)
 
 	if(op == OPRINTN)
 		calls = list(calls, mkcall("printnl", T, nil));
+
+	calls = list(calls, mkcall("printunlock", T, init));
+
 	typechecklist(calls, Etop);
 	walkexprlist(calls, init);
 
@@ -1987,6 +2005,9 @@ applywritebarrier(Node *n, NodeList **init)
 {
 	Node *l, *r;
 	Type *t;
+	vlong x;
+	static Bvec *bv;
+	char name[32];
 
 	if(n->left && n->right && needwritebarrier(n->left, n->right)) {
 		t = n->left->type;
@@ -2004,14 +2025,35 @@ applywritebarrier(Node *n, NodeList **init)
 		} else if(isinter(t)) {
 			n = mkcall1(writebarrierfn("writebarrieriface", t, n->right->type), T, init,
 				l, n->right);
-		} else if(t->width == 2*widthptr) {
-			n = mkcall1(writebarrierfn("writebarrierfat2", t, n->right->type), T, init,
-				l, nodnil(), n->right);
-		} else if(t->width == 3*widthptr) {
-			n = mkcall1(writebarrierfn("writebarrierfat3", t, n->right->type), T, init,
-				l, nodnil(), n->right);
-		} else if(t->width == 4*widthptr) {
-			n = mkcall1(writebarrierfn("writebarrierfat4", t, n->right->type), T, init,
+		} else if(t->width <= 4*widthptr) {
+			x = 0;
+			if(bv == nil)
+				bv = bvalloc(BitsPerPointer*4);
+			bvresetall(bv);
+			twobitwalktype1(t, &x, bv);
+			// The bvgets are looking for BitsPointer in successive slots.
+			enum {
+				PtrBit = 1,
+			};
+			if(BitsPointer != (1<<PtrBit))
+				fatal("wrong PtrBit");
+			switch(t->width/widthptr) {
+			default:
+				fatal("found writebarrierfat for %d-byte object of type %T", (int)t->width, t);
+			case 2:
+				snprint(name, sizeof name, "writebarrierfat%d%d",
+					bvget(bv, PtrBit), bvget(bv, BitsPerPointer+PtrBit));
+				break;
+			case 3:
+				snprint(name, sizeof name, "writebarrierfat%d%d%d",
+					bvget(bv, PtrBit), bvget(bv, BitsPerPointer+PtrBit), bvget(bv, 2*BitsPerPointer+PtrBit));
+				break;
+			case 4:
+				snprint(name, sizeof name, "writebarrierfat%d%d%d%d",
+					bvget(bv, PtrBit), bvget(bv, BitsPerPointer+PtrBit), bvget(bv, 2*BitsPerPointer+PtrBit), bvget(bv, 3*BitsPerPointer+PtrBit));
+				break;
+			}
+			n = mkcall1(writebarrierfn(name, t, n->right->type), T, init,
 				l, nodnil(), n->right);
 		} else {
 			r = n->right;
@@ -2873,6 +2915,11 @@ copyany(Node *n, NodeList **init, int runtimecall)
 {
 	Node *nl, *nr, *nfrm, *nto, *nif, *nlen, *nwid, *fn;
 	NodeList *l;
+	
+	if(haspointers(n->left->type->type)) {
+		fn = writebarrierfn("writebarriercopy", n->left->type, n->right->type);
+		return mkcall1(fn, n->type, init, typename(n->left->type->type), n->left, n->right);
+	}
 
 	if(runtimecall) {
 		if(n->right->type->etype == TSTRING)