gcc: merge small upstream change.

Backport from mainline:
2007-04-24  Hui-May Chang <hm.chang@apple.com>

* reload1.c (merge_assigned_reloads) : Do not merge a RELOAD_OTHER
instruction with a RELOAD_FOR_OPERAND_ADDRESS instruction.

Obtained from:	gcc 4.3 (rev. r124115: GPLv2)
MFC after:	1 week
sh: Don't check input for non-whitespace if history is disabled.

preadbuffer() maintained a flag whether there was any non-whitespace
character. This flag is only useful when history is enabled (in that case,
lines containing only whitespace are not added to history). Instead, check
using strspn() when history is enabled.

There is an approximate 2% speedup when running
  sh -c '. /etc/rc.subr; . /etc/defaults/rc.conf; source_rc_confs'
with hot cache.
Improve wording slightly.
- Fix EBADF description, in following the future POSIX tc and what FreeBSD
  actually implements.
- Improve grammar: use more preferred "can", not "could".

Submitted by:	jilles
Do not coalesce stack entry, vm_map_stack() asserts that the requested
region is claimed by a new entry.

Pass MAP_STACK_GROWS_DOWN and MAP_STACK_GROWS_UP flags to
vm_map_insert() from vm_map_stack(), to really turn off coalescing
code and call to vm_map_simplify_entry() [1].

Reported by:	avg, peter, many
Tested by:	avg, peter
Noted by:	avg [1]
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Revert r259200.  There are geoms/drivers which do not update
bio_completed, only manage bio_resid, e.g. sa(4).

Reported and tested by:	Manfred Antar <null@pozo.com>
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Fix accounting for the negative cache entries when reusing v_cache_dd.
Having ncneg diverge with the actual length of the ncneg tailq causes
NULL dereference.

Add assertion that an entry taken from ncneg queue is indeed negative.

Reported by and discussed with:	avg
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Move build_doc_ports() to the if...fi block from which it is called.

Sponsored by:	The FreeBSD Foundation
Add the scaffolding for minidumps. They're just like physical dumps,
except the chunks aren't physical memory regions but virtual memory
regions. In both cases, the core file is an ELF file and flags in
the header allow libkvm to distinguish one from the other.
Modify handling of writes to the vlapic ICR_TIMER, DCR_TIMER, ICRLO and ESR
registers.

The handler is now called after the register value is updated in the virtual
APIC page. This will make it easier to handle APIC-write VM-exits with APIC
register virtualization turned on.

We can no longer rely on the value of 'icr_timer' on the APIC page
in the callout handler. With APIC register virtualization the value of
'icr_timer' will be updated by the processor in guest-context before an
APIC-write VM-exit.

Clear the 'delivery status' bit in the ICRLO register in the write handler.
With APIC register virtualization the write happens in guest-context and
we cannot prevent a (buggy) guest from setting this bit.
Tighten default restrictions for ntpd(8) server and provide a link
to NTP access restriction documentation.

The new default restrictions would allow only time queries from a
remote system and will KoD all other requests, but still allow
localhost to do make all requests.

These restrictions are also recommended for all Internet-facing
public NTP servers.

This changeset is intended for an instant MFC to stable/10 and
releng/10.0.
Modify handling of writes to the vlapic LVT registers.

The handler is now called after the register value is updated in the virtual
APIC page. This will make it easier to handle APIC-write VM-exits with APIC
register virtualization turned on.

This also implies that we need to keep a snapshot of the last value written
to a LVT register. We can no longer rely on the LVT registers in the APIC
page to be "clean" because the guest can write anything to it before the
hypervisor has had a chance to sanitize it.
Correct the description of the V state, which indicates that the process'
parent is suspended, not the process itself.

MFC after:	3 days
Use pthread_once() to replace a static integer initted flag.

Reviewed by:	neel
Extend the ACPI power management support to wire a virtual power button up
to SIGTERM when ACPI is enabled.  Sending SIGTERM to the hypervisor when an
ACPI-aware OS is running will now trigger a soft-off allowing for a graceful
shutdown of the guest.
- Move constants for ACPI-related registers to acpi.h.
- Implement an SMI_CMD register with commands to enable and disable ACPI.
  Currently the only change when ACPI is enabled is to enable the virtual
  power button via SIGTERM.
- Implement a fixed-feature power button when ACPI is enabled by asserting
  PWRBTN_STS in PM1_EVT when SIGTERM is received.
- Add support for EVFILT_SIGNAL events to mevent.
- Implement support for the ACPI system command interrupt (SCI) and assert
  it when needed based on the values in PM1_EVT.  Mark the SCI as active-low
  and level triggered in the MADT and MP Table.
- Mark PCI interrupts in the MP Table as active-low in addition to level
  triggered.

Reviewed by:	neel
MFp4 alc_popmap
  Change the way that reservations keep track of which pages are in use.
  Instead of using the page's PG_CACHED and PG_FREE flags, maintain a bit
  vector within the reservation.  This approach has a couple benefits.
  First, it makes breaking reservations much cheaper because there are
  fewer cache misses to identify the unused pages.  Second, it is a pre-
  requisite for supporting two or more reservation sizes.
Fix the Intel 6150 support.

This chip doesn't require the temperature sensor offset, either v1 or
v2.  Doing so causes the initial calibration test to fail.

Tested:

* Intel Centrino 6150
In libiconv_modules, surround unused static _citrus_XXX_pack_state() and
_citrus_XXX_unpack_state() functions with #if 0, for now.

MFC after:	3 days
Add a virt_foreach() that does the same as what phys_foreach() does and
change virt_size(), virt_dumphdrs() and virt_dumpdata() into its callback
functions.
In virt_foreach() we iterate over all the virtual memory regions that we
want in the minidump. For now, just start with the PBVM (= kernel text
and data plus preloaded modules). The core file this produces can already
be used to work out the libkvm changes that need to be made to support it.
In parallel, we can flesh out the in-kernel bits to dump more of what we
need in a minidump without changing the core file structure.
Bump __FreeBSD_version for r259951 - Don't coalesce entries in
vm_map_stack().