runtime: simplify mallocgc flag argument

mallocgc can calculate noscan itself.  The only remaining
flag argument is needzero, so we just make that a boolean arg.

Fixes #15379

Change-Id: I839a70790b2a0c9dbcee2600052bfbd6c8148e20
Reviewed-on: https://go-review.googlesource.com/22290
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/src/runtime/string.go b/src/runtime/string.go
index 2d20e0a9c3..112ce5d588 100644
--- a/src/runtime/string.go
+++ b/src/runtime/string.go
@@ -284,7 +284,7 @@ func stringiter2(s string, k int) (int, rune) {
 // The storage is not zeroed. Callers should use
 // b to set the string contents and then drop b.
 func rawstring(size int) (s string, b []byte) {
-	p := mallocgc(uintptr(size), nil, flagNoScan|flagNoZero)
+	p := mallocgc(uintptr(size), nil, false)
 
 	stringStructOf(&s).str = p
 	stringStructOf(&s).len = size
@@ -302,7 +302,7 @@ func rawstring(size int) (s string, b []byte) {
 // rawbyteslice allocates a new byte slice. The byte slice is not zeroed.
 func rawbyteslice(size int) (b []byte) {
 	cap := roundupsize(uintptr(size))
-	p := mallocgc(cap, nil, flagNoScan|flagNoZero)
+	p := mallocgc(cap, nil, false)
 	if cap != uintptr(size) {
 		memclr(add(p, uintptr(size)), cap-uintptr(size))
 	}
@@ -317,7 +317,7 @@ func rawruneslice(size int) (b []rune) {
 		throw("out of memory")
 	}
 	mem := roundupsize(uintptr(size) * 4)
-	p := mallocgc(mem, nil, flagNoScan|flagNoZero)
+	p := mallocgc(mem, nil, false)
 	if mem != uintptr(size)*4 {
 		memclr(add(p, uintptr(size)*4), mem-uintptr(size)*4)
 	}