Commit Graph

124 Commits

Author SHA1 Message Date
Dimitry Andric
0514e96282 Pull in r196658 from upstream clang trunk:
CodeGen: Don't emit linkage on thunks that aren't emitted because they're
  vararg.

  This can happen when we're trying to emit a thunk with available_externally
  linkage with optimization enabled but bail because it doesn't make sense for
  vararg functions.

  [LLVM] PR18098.

This should fix clang "Broken module found, compilation aborted" errors when
building the qt4-based dvbcut port.

Reported by:	se
MFC after:	3 days
2013-12-08 13:56:26 +00:00
Dimitry Andric
914afe13c2 Pull in r196590 from upstream clang trunk (by rdivacky):
Move the body of GCCInstallationDetector ctor into an init() function
  and call it from its only user. The linux toolchain. This saves quite
  a lot of directory searching on other platforms.

See http://docs.freebsd.org/cgi/mid.cgi?51E6FAF5.3080802 for the
original discussion.  With this fix, the search for gcc installations is
completely eliminated on FreeBSD.

Reported by:	Kurt Lidl <lidl@pix.net>
MFC after:	3 days
2013-12-07 00:05:45 +00:00
Ed Maste
a4849615b2 Update LLDB to upstream r196322 snapshot
Upstream revisions of note:
r196298 - Fix use of std::lower_bound
r196322 - Fix log message for new invalidation checks

Sponsored by:	DARPA, AFRL
2013-12-03 22:26:38 +00:00
Ed Maste
04c171520d lldb: Threaded inferior support for FreeBSD
This is in the process of being submitted to the upstream LLDB
repository.  The thread list functionality is modelled in part on
GDBRemoteCommunicationClient.

LLDB bug pr16696 and code review D2267

Sponsored by:	DARPA, AFRL
2013-12-03 21:29:45 +00:00
Ed Maste
b952cd584f Update LLDB to upstream r196259 snapshot
Sponsored by:	DARPA, AFRL
2013-12-03 19:23:54 +00:00
Ed Maste
9151c81ccb Workaround lldb issue with main module base address
On FreeBSD lldb sometimes reloads the the main module's (executable's)
symbols at the wrong address.  Work around this for now by explicitly
reloading at base_address=0 when it happens.

A proper fix is needed but early testers have reported this issue so
this workaround should allow them to make further progress.

http://llvm.org/bugs/show_bug.cgi?id=17880
2013-12-03 18:12:51 +00:00
Dimitry Andric
ce67429848 Pull in r195558 from upstream clang trunk:
Fix a SSE2 intrinsics typo

  Full discourse at:

   http://lists.cs.uiuc.edu/pipermail/cfe-commits/Week-of-Mon-20131104/092514.html
   http://lists.cs.uiuc.edu/pipermail/llvmdev/2013-November/068124.html

  Patch by Dimitry Andric and Alexey Dokuchaev!

Reported by:	danfe
MFC after:	3 days
2013-11-26 08:07:45 +00:00
Dimitry Andric
56510193f0 Revert r258455 for now, as it apparently causes miscompilation in some
situations.  Until this is fully resolved, the X.org workaround in ports
still needs to take place.
2013-11-22 17:54:53 +00:00
Dimitry Andric
711f10ae9f Pull in r195318 from upstream llvm trunk:
The basic problem is that some mainstream programs cannot deal with the way
  clang optimizes tail calls, as in this example:

  int foo(void);
  int bar(void) {
  return foo();
  }

  where the call is transformed to:

   calll .L0$pb
  .L0$pb:
   popl  %eax
  .Ltmp0:
   addl  $_GLOBAL_OFFSET_TABLE_+(.Ltmp0-.L0$pb), %eax
   movl  foo@GOT(%eax), %eax
   popl  %ebp
   jmpl  *%eax                   # TAILCALL

  However, the GOT references must all be resolved at dlopen() time, and so this
  approach cannot be used with lazy dynamic linking (e.g. using RTLD_LAZY), which
  usually populates the PLT with stubs that perform the actual resolving.

  This patch changes X86TargetLowering::LowerCall() to skip tail call
  optimization, if the called function is a global or external symbol.

This fixes problems with loading X.org driver modules, which could occur
when X.org was compiled on i386 with tailcall optimization on, for which
ports r312583 was committed as a workaround.  After this change, the
workaround can be removed.

MFC after:	3 days
2013-11-21 23:09:07 +00:00
Dimitry Andric
110f993aa9 Pull in r191896 from upstream llvm trunk:
CaptureTracking: Plug a loophole in the "too many uses" heuristic.

  The heuristic was added to avoid spending too much compile time in a
  specially crafted test case (PR17461, PR16474) with many uses on a
  select or bitcast instruction can still trigger the slow case. Add a
  check for that case.

  This only affects compile time, don't have a good way to test it.

This fixes the excessive compile time spent on a specific file of the
graphics/rawtherapee port.

Reported by:	mandree
MFC after:	3 days
2013-11-19 17:53:19 +00:00
Ed Maste
afda932a71 Merge upstream LLDB r194487:
Log failure to restore thread state in ThreadPlanCallFunction::DoTakedown

  In order to help track down llvm.org/pr17226.

Sponsored by:	DARPA, AFRL
2013-11-13 17:06:26 +00:00
Ed Maste
4d1da75392 lldb: Correct a standalone debug file path
For a file /bin/ls with a .gnu_debuglink entry of "ls.debug" the path
should be /usr/lib/debug/bin/ls.debug, not /usr/lib/debug/bin/ls.

ref: https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html

Upstream defect pr17903 (http://llvm.org/pr17903)

Sponsored by:	DARPA, AFRL
2013-11-13 14:46:41 +00:00
Ed Maste
3561791104 Update LLDB to upstream r194122 snapshot
ludes minor changes relative to upstream, for compatibility with
FreeBSD's in-tree LLVM 3.3:

- Reverted LLDB r191806, restoring use of previous API.
- Reverted part of LLDB r189317, restoring previous enum names.
- Work around missing LLVM r192504, using previous registerEHFrames API
  (limited functionality).
- Removed PlatformWindows header include and init/terminate calls.

Sponsored by:	DARPA, AFRL
2013-11-12 17:25:33 +00:00
Ed Maste
0adcb21d02 Merge upstream LLVM r192118:
Formally added an explicit enum for DWARF TLS support. No functionality
  change.

Reviewed by:	dim@
Sponsored by:	DARPA, AFRL
2013-11-11 19:06:12 +00:00
Ed Maste
66cbfb81eb Merge upstream LLVM r182803:
[Mips] Add Mips specific dynamic table entry tags.

This is to support an upcoming LLDB snapshot update.

Reviewed by:	dim@
Sponsored by:	DARPA, AFRL
2013-11-11 19:00:20 +00:00
Steven Hartland
3e8aed7f71 Add clang-CC and CC to list of hints allowing clang to identify its operating
mode as c++ instead of defaulting to c for the binary names CC and clang-CC.

This fixes builds that use cmake, which automatically sets CXX to
/usr/bin/CC by default.

PR:		bin/182442
Reviewed by:	dwhite, wca
MFC after:	2 days
2013-10-25 09:09:00 +00:00
Dimitry Andric
7ae3e01a31 Pull in r192064 from upstream llvm trunk:
X86: Don't fold spills into SSE operations if the stack is unaligned.

  Regalloc can emit unaligned spills nowadays, but we can't fold the
  spills into SSE ops if we can't guarantee alignment. PR12250.

This fixes unaligned SSE accesses (leading to a SIGBUS) which could
occur in the ffmpeg ports.

Approved by:	re (kib)
Reported by:	tijl
MFC after:	3 days
2013-10-06 16:12:45 +00:00
Dimitry Andric
5b3c2be312 Pull in r189644 from upstream llvm trunk:
Add ms_abi and sysv_abi attribute handling.

  Based on a patch by Benno Rice!

This will help to develop EFI support.

Approved by:	re (kib)
Verified by:	benno
MFC after:	1 week
2013-10-03 20:38:57 +00:00
Dimitry Andric
75345ac580 Pull in r186338 from upstream llvm trunk:
Remove invalid assert in DAGTypeLegalizer::RemapValue

  There is a comment at the top of DAGTypeLegalizer::PerformExpensiveChecks
  which, in part, says:

   // Note that these invariants may not hold momentarily when processing a node:
   // the node being processed may be put in a map before being marked Processed.

  Unfortunately, this assert would be valid only if the above-mentioned invariant
  held unconditionally. This was causing llc to assert when, in fact,
  everything was fine.

  Thanks to Richard Sandiford for investigating this issue!

  Fixes PR16562.

This fixes assertions which could occur in the multimedia/ffmpeg1 and
multimedia/ffmpeg2 ports.

Approved by:	re (hrs)
Reported by:	Matthias Apitz <guru@unixarea.de>
MFC after:	3 days
2013-10-03 17:50:14 +00:00
Dimitry Andric
1f27f9b50b Pull in r191711 from upstream llvm trunk:
The X86FixupLEAs pass for Intel Atom must not call
  convertToThreeAddress on ADD16rr opcodes, if src1 != src, since that
  would cause convertToThreeAddress to try to create a virtual register.
  This is not permitted after register allocation, which is when the
  X86FixupLEAs pass runs.

  This patch fixes PR16785.

Pull in r191715 from upstream llvm trunk:

  Forgot to add a break statement.

This should enable building the x11-toolskits/libXaw port with
CPUTYPE=atom.

Approved by:	re (gjb)
Reported by:	Kenta Suzumoto <kentas@hush.com>
MFC after:	3 days
2013-10-01 19:14:24 +00:00
Dimitry Andric
462fc0e072 Pull in r191165 from upstream llvm trunk:
ISelDAG: spot chain cycles involving MachineNodes

  Previously, the DAGISel function WalkChainUsers was spotting that it
  had entered already-selected territory by whether a node was a
  MachineNode (amongst other things). Since it's fairly common practice
  to insert MachineNodes during ISelLowering, this was not the correct
  check.

  Looking around, it seems that other nodes get their NodeId set to -1
  upon selection, so this makes sure the same thing happens to all
  MachineNodes and uses that characteristic to determine whether we
  should stop looking for a loop during selection.

  This should fix PR15840.

Specifically, this fixes the long-standing assertion failure when
compiling the multimedia/gstreamer port on i386.  Thanks to Tijl
Coosemans for his help in getting upstream to fix it.

Approved by:	re (marius)
2013-09-22 22:03:30 +00:00
Ed Maste
34ff737fae Disable LLDB OSX ABI plugin
Approved by:	re (blanket)
2013-09-20 01:18:50 +00:00
Ed Maste
fc8b9f8f79 Merge lldb man page from r188801 to contrib/llvm/tools/lldb/docs/
Approved by:	re (gjb)
2013-09-19 00:32:07 +00:00
David Chisnall
52b42bace1 On platforms where clang is the default compiler, don't build gcc or libstdc++.
To enable them, set WITH_GCC and WITH_GNUCXX in src.conf.
Make clang default to using libc++ on FreeBSD 10.
Bumped __FreeBSD_version for the change.

GCC is still enabled on PC98, because the PC98 bootloader requires GCC to build
(or, at least, hard-codes the use of gcc into its build).

Thanks to everyone who helped make the ports tree ready for this (and bapt
for coordinating them all).  Also to imp for reviewing this and working on the
forward-porting of the changes in our gcc so that we're getting to a much
better place with regard to external toolchains.

Sorry to all of the people who helped who I forgot to mention by name.

Reviewed by:	bapt, imp, dim, ...
2013-09-06 20:08:03 +00:00
Dimitry Andric
89a53411d4 Pull in r189672 from upstream llvm trunk:
InstCombine: Check for zero shift amounts before subtracting one
  causing integer overflow.

  PR17026. Also avoid undefined shifts and shift amounts larger than 64
  bits (those are always undef because we can't represent integer types
  that large).

This should fix assertion failures when building the emulators/xmame
port.

Reported by:	bapt
2013-08-30 18:29:25 +00:00
Ed Maste
d09607dfdb Disable lldb target support not (currently) of interest
- Remote iOS debugging
- OS X symbol provider, core files
- PECOFF object files
- Linux platform support

Sponsored by:	DARPA, AFRL
2013-08-25 12:07:34 +00:00
Ed Maste
3979636f6f Revert lldb change for Attribute::NoBuiltin
NoBuiltin was introduced after clang/llvm 3.3 and thus does not exist in
FreeBSD.  Thus special handling for the attribute is not needed in lldb.

This reverts lldb r186990 (git eebd175)

Sponsored by:	DARPA, AFRL
2013-08-24 16:09:52 +00:00
Ed Maste
265a85219f Import llvm r187614 (git 44c8e34), for lldb's use:
Author: Daniel Malea <daniel.malea@intel.com>
  Date:   Thu Aug 1 21:18:16 2013 +0000

    Fixed the Intel-syntax X86 disassembler to respect the (existing)
    option for hexadecimal immediates, to match AT&T syntax. This also
    brings a new option for C-vs-MASM-style hex.

    Patch by Richard Mitton
    Reviewed: http://llvm-reviews.chandlerc.com/D1243
2013-08-24 15:33:17 +00:00
Ed Maste
7e7299d197 Revert lldb changes due to post-3.3 clang and llvm API changes
Revisions:
svn	git
183929	99447a6
183862	15c1774
  source/Host/common/FileSpec.cpp

184954	007e7bc
184948	4dc3761
  source/Expression/ClangExpressionParser.cpp

182099	b31044e
181387	779e6ac
  include/lldb/Expression/IRExecutionUnit.h
  source/Expression/IRExecutionUnit.cpp

184177	0b2934b
182650	f2dcf35
181703	7bef4e2
  source/Plugins/Disassembler/llvm/DisassemblerLLVMC.cpp

182683	0d91b80
  source/Plugins/Instruction/ARM/EmulateInstructionARM.cpp

Sponsored by:	DARPA, AFRL
2013-08-24 10:06:51 +00:00
Ed Maste
ac7ddfbf72 Merge lldb r188801 to contrib/llvm/tools/lldb/ 2013-08-23 18:06:42 +00:00
Dimitry Andric
992b133da5 Pull in r182983 from upstream clang trunk:
Fix handling of braced-init-list as reference initializer within
  aggregate initialization. Previously we would incorrectly require an
  extra set of braces around such initializers.

Pull in r188718 from upstream clang trunk:

  Handle init lists and _Atomic fields.

  Fixes PR16931.

These fixes are needed for the atomic_flag type to work correctly in our
stdatomic.h.

Requested by:	theraven
2013-08-20 20:51:32 +00:00
Dimitry Andric
df2637d88a Pull in r188716 from upstream clang trunk:
PR16727: don't try to evaluate a potentially value-dependent
  expression when checking for missing parens in &&/|| expressions.

This fixes an assertion encountered when building the lang/sdcc port.

Reported by:	kwm
2013-08-20 20:46:29 +00:00
Dimitry Andric
12ebae77ad Pull in r186696 from upstream clang trunk:
This patch implements __get_cpuid_max() as an inline and __cpuid()
  and __cpuid_count() as macros to be compatible with GCC's cpuid.h.
  It also adds bit_<foo> constants for the various feature bits as
  described in version 039 (May 2011) of Intel's SDM Volume 2 in the
  description of the CPUID instruction.  The list of bit_<foo>
  constants is a bit exhaustive (GCC doesn't do near this many).  More
  bits could be added from a newer version of SDM if desired.

  Patch by John Baldwin!

This should fix several ports which depend on this functionality being
available.

MFC after:	1 week
2013-07-30 12:33:21 +00:00
Dimitry Andric
7a06320990 Pull in r185616 from llvm trunk:
FastISel can only append to basic blocks.

  Compute the insertion point from the end of the basic block instead of
  skipping labels from the front.

  This caused failures in landing pads when live-in copies where inserted
  before instruction selection.

I missed this change in r252720; without it, certain compilation flags
can cause exception labels to not be generated, but still referenced,
leading to link errors.

Reported by:	zeising
MFC after:	3 days
2013-07-08 17:57:11 +00:00
Dimitry Andric
6beeb09142 Pull in r185594 from llvm trunk:
Add MachineBasicBlock::addLiveIn().

  This function adds a live-in physical register to an MBB and ensures
  that it is copied to a virtual register immediately.

Pull in r185615 from llvm trunk:

  Live-in copies go *after* EH_LABELs.

  This will soon be tested by exception handling working at all.

Pull in r185617 from llvm trunk:

  Simplify landing pad lowering.

  Stop using the ISD::EXCEPTIONADDR and ISD::EHSELECTION when lowering
  landing pad arguments. These nodes were previously legalized into
  CopyFromReg nodes, but that never worked properly because the
  CopyFromReg node weren't guaranteed to be  scheduled at the top of the
  basic block.

  This meant the exception pointer and selector registers could be
  clobbered before being copied to a virtual register.

  This patch copies the two physical registers to virtual registers at
  the beginning of the basic block, and lowers the landingpad instruction
  directly to two CopyFromReg nodes reading the *virtual* registers. This
  is safe because virtual registers don't get clobbered.

  A future patch will remove the ISD::EXCEPTIONADDR and ISD::EHSELECTION
  nodes.

Together, these changes fix llvm PR 16038 ('qt4 webcore file results in
"Bad machine code: Using an undefined physical register"'), and should
make it possible again to compile the www/qt4-webkit port again on the
i386 arch, without using a CPUTYPE=i686 or higher setting.
2013-07-04 20:10:33 +00:00
Dimitry Andric
0cf157db98 Pull in r185446 from clang trunk:
Fix to PR15826 - clang hits assert in clang::ASTContext::getASTRecordLayout.

Reported by:	glebius
2013-07-03 19:08:10 +00:00
Andrew Turner
b206d4e77f Work around an ARM EABI issue where clang would sometimes incorrectly align
the stack in a leaf function that uses TLS.

The issue is, when using TLS, the function is no longer a leaf as it calls
__aeabi_read_tp. With statically linked programs this is not an issue as
it doesn't make use of the stack, however with dynamically linked
applications we enter rtld which does use the stack and makes assumptions
about it's alignment.

This is only a temporary fix until a better patch can be made and submitted
upstream.
2013-07-02 08:04:41 +00:00
Dimitry Andric
707d0cef66 Pull in r183984 from llvm trunk:
Make PrologEpilogInserter save/restore all callee saved registers in
  functions which call __builtin_unwind_init()

  __builtin_unwind_init() is an undocumented gcc intrinsic which has
  this effect, and is used in libgcc_eh.

  Goes part of the way toward fixing PR8541.

This obsoletes the ugly hack to libgcc's unwind code from r245272, and
should also work for other arches, so revert the hack too.
2013-06-20 18:25:10 +00:00
Andrew Turner
1f4f127b99 Pull in r183926 from LLVM trunk:
Allow clang to build __clear_cache on ARM.

  __clear_cache is special. It needs no signature, but is a real function in
  compiler_rt or libgcc.

  Patch by Andrew Turner.

This allows us to build the __clear_cache function in compiler-rt.
2013-06-15 12:13:22 +00:00
Ed Schouten
d23f3f67b5 Pull in r184040 from upstream clang trunk:
Emit native implementations of atomic operations on FreeBSD/armv6.

  Just like on Linux, FreeBSD/armv6 assumes the system supports
  ldrex/strex unconditionally. It is also used by the kernel. We can
  therefore enable support for it, like we do on Linux.

  While there, change one of the unit tests to explicitly test against
  armv5 instead of armv7, as it actually tests whether libcalls are
  emitted.
2013-06-15 09:42:43 +00:00
Dimitry Andric
b6fdb9ab2f Pull in r181620 from llvm trunk:
[ms-inline asm] Fix a crasher when we fail on a direct match.

  The issue was that the MatchingInlineAsm and VariantID args to the
  MatchInstructionImpl function weren't being set properly.  Specifically, when
  parsing intel syntax, the parser thought it was parsing inline assembly in the
  at&t dialect; that will never be the case.

  The crash was caused when the emitter tried to emit the instruction, but the
  operands weren't set.  When parsing inline assembly we only set the opcode, not
  the operands, which is used to lookup the instruction descriptor.
  rdar://13854391 and PR15945

  Also, this commit reverts r176036.  Now that we're correctly parsing the intel
  syntax the pushad/popad don't match properly.  I've reimplemented that fix using
  a MnemonicAlias.

Pull in r183907 from llvm trunk:

  X86: Make the cmov aliases work with intel syntax too.

These commits make a number of Intel-style inline assembly mnemonics
aliases (occurring in several ports) work properly, which could cause
assertions otherwise.

Reported by:	kwm, bapt
2013-06-14 21:14:36 +00:00
Dimitry Andric
284c197886 Upgrade our copy of llvm/clang to 3.3 release.
Release notes are still in the works, these will follow soon.

MFC after:	1 month
2013-06-12 18:48:53 +00:00
Dimitry Andric
89d5a4380e Pull in r183297 from upstream llvm trunk:
PR15662: Optimized debug info produces out of order function
  parameters

  When a function is inlined we lazily construct the variables
  representing the function's parameters. After that, we add any
  remaining unused parameters.

  If the function doesn't use all the parameters, or uses them out of
  order, then the DWARF would produce them in that order, producing a
  parameter order that doesn't match the source.

  This fix causes us to always keep the arg variables at the start of
  the variable list & in the original order from the source.

Reported by:	avg
MFC after:	1 week
2013-06-05 19:46:39 +00:00
Ed Schouten
6306ff32fd Pull in r183033 and r183036 from LLVM trunk:
Add support for optimized (non-generic) atomic libcalls.

  For integer types of sizes 1, 2, 4 and 8, libcompiler-rt (and libgcc)
  provide atomic functions that pass parameters by value and return
  results directly.

  libgcc and libcompiler-rt only provide optimized libcalls for
  __atomic_fetch_*, as generic libcalls on non-integer types would make
  little sense. This means that we can finally make __atomic_fetch_*
  work
  on architectures for which we don't provide these operations as
  builtins
  (e.g. ARM).

  This should fix the dreaded "cannot compile this atomic library call
  yet" error that would pop up once every while.

This should make it possible for me to get C11 atomics working on all of
our platforms.
2013-06-01 08:07:09 +00:00
Dimitry Andric
b3eb0ffbc9 Pull in r182656 from upstream llvm trunk:
LoopVectorize: LoopSimplify can't canonicalize loops with an
  indirectbr in it, don't assert on those cases.

  Fixes PR16139.

This should fix clang assertion failures when optimizing at -O3, similar
to:

  Assertion failed: (TheLoop->getLoopPreheader() && "No preheader!!"),
  function canVectorize, file
  contrib/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp, line 2171.

Reported by:	O. Hartmann <ohartman@zedat.fu-berlin.de>
PR:		ports/178332, ports/178977
MFC after:	3 days
2013-05-26 14:14:42 +00:00
Dimitry Andric
779aaa5564 Pull in r181286 from upstream llvm trunk:
LoopVectorize: getConsecutiveVector must respect signed arithmetic

  We were passing an i32 to ConstantInt::get where an i64 was needed and we must
  also pass the sign if we pass negatives numbers. The start index passed to
  getConsecutiveVector must also be signed.

  Should fix PR15882.

This should fix Firefox crashes some people have been reporting, when it
is compiled with -O3.
2013-05-13 07:02:15 +00:00
Dimitry Andric
5c47cd667d Pull in r180121 from upstream llvm trunk:
LoopVectorizer: Fix 15830. When scalarizing and unrolling stores make
  sure that the order in which the elements are scalarized is the same
  as the original order.
  This fixes a miscompilation in FreeBSD's regex library.

This should fix lib/libc/regex/regcomp.c at -O3 with clang 3.3 r178860
on CPUs with SSE.  Before this change, the vectorizer could incorrectly
rearrange the second loop in computejumps(), leading to possibly invalid
entries in the re_gets::charjump table.

The net result was that for example "sed s/@CC@/foo/" failed to work
correctly, leading to trouble with many configure scripts.
2013-04-23 18:58:39 +00:00
Dimitry Andric
139f7f9bf5 Upgrade our copy of llvm/clang to trunk r178860, in preparation of the
upcoming 3.3 release (branching and freezing expected in a few weeks).

Preliminary release notes can be found at the usual location:
<http://llvm.org/docs/ReleaseNotes.html>

An MFC is planned once the actual 3.3 release is finished.
2013-04-12 17:57:40 +00:00
Andrew Turner
e9a848494f Pull in r177252 from upstream clang trunk:
Make sure to use same EABI version for external assembler as for
 integrated as.

This allows us to use gcc on a world built with clang on ARM.
2013-03-20 08:34:30 +00:00
Dimitry Andric
b2a67e7b16 Pull in r175962 from upstream llvm trunk:
X86: Disable cmov-memory patterns on subtargets without cmov.

  Fixes PR15115.

For the i386 arch, this should enable cmov instructions only on
-march=pentiumpro and higher.  Since our default CPU is i486, cmov
instructions will now be disabled by default.

MFC after:	1 week
2013-02-23 22:48:12 +00:00