From: Josh Bleecher Snyder <josharian@gmail.com>
Date: Wed, 7 Jun 2017 18:35:17 +0000 (-0700)
Subject: runtime: CSE some function arguments in evacuate
X-Git-Tag: go1.10beta1~1622
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=aca92f352d6a5bc0b17cd39d3b1bbe23ae0bb5ac;p=gostls13.git

runtime: CSE some function arguments in evacuate

Shrinks evacuate's machine code a little.

Change-Id: I08874c92abdc7e621bc0737e22f2a6be31542cab
Reviewed-on: https://go-review.googlesource.com/54652
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
---

diff --git a/src/runtime/hashmap.go b/src/runtime/hashmap.go
index e8e61a7fd1..c36ff470d6 100644
--- a/src/runtime/hashmap.go
+++ b/src/runtime/hashmap.go
@@ -1166,10 +1166,12 @@ func evacuate(t *maptype, h *hmap, oldbucket uintptr) {
 			b = (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.bucketsize)))
 			// Preserve b.tophash because the evacuation
 			// state is maintained there.
+			ptr := add(unsafe.Pointer(b), dataOffset)
+			n := uintptr(t.bucketsize) - dataOffset
 			if t.bucket.kind&kindNoPointers == 0 {
-				memclrHasPointers(add(unsafe.Pointer(b), dataOffset), uintptr(t.bucketsize)-dataOffset)
+				memclrHasPointers(ptr, n)
 			} else {
-				memclrNoHeapPointers(add(unsafe.Pointer(b), dataOffset), uintptr(t.bucketsize)-dataOffset)
+				memclrNoHeapPointers(ptr, n)
 			}
 		}
 	}