[src/trunk]: src/sys/uvm Optimize out VM_PHYSMEM_PTR_SWAP on architectures th...

[martin <martin%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/8f05de5194a7
branches:  trunk
changeset: 790856:8f05de5194a7
user:      martin <martin%NetBSD.org@localhost>
date:      Fri Oct 25 14:30:21 2013 +0000

description:
Optimize out VM_PHYSMEM_PTR_SWAP on architectures that have VM_PHYSSEG_MAX = 1
(hard to address two different array entries there w/o invoking undefined
behaviour, and newer compilers complain about it).

diffstat:

 sys/uvm/uvm_page.h |  6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)

diffs (22 lines):

diff -r ae676c354f1a -r 8f05de5194a7 sys/uvm/uvm_page.h
--- a/sys/uvm/uvm_page.h        Fri Oct 25 14:28:28 2013 +0000
+++ b/sys/uvm/uvm_page.h        Fri Oct 25 14:30:21 2013 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uvm_page.h,v 1.75 2012/05/05 20:45:35 rmind Exp $      */
+/*     $NetBSD: uvm_page.h,v 1.76 2013/10/25 14:30:21 martin Exp $     */
 
 /*
  * Copyright (c) 1997 Charles D. Cranor and Washington University.
@@ -290,8 +290,12 @@
  */
 
 #define        VM_PHYSMEM_PTR(i)       (&vm_physmem[i])
+#if VM_PHYSSEG_MAX == 1
+#define VM_PHYSMEM_PTR_SWAP(i, j) /* impossible */
+#else
 #define VM_PHYSMEM_PTR_SWAP(i, j) \
        do { vm_physmem[(i)] = vm_physmem[(j)]; } while (0)
+#endif
 
 extern struct vm_physseg vm_physmem[VM_PHYSSEG_MAX];
 extern int vm_nphysseg;