Move EmitTargetCodeForMemcpy, EmitTargetCodeForMemset, and
EmitTargetCodeForMemmove out of TargetLowering and into
SelectionDAGInfo to exercise this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103481 91177308-0d34-0410-b5e6-96231b3b80d8
optimization for non-leaf functions. This will be hooked up to gcc's
-momit-leaf-frame-pointer option. rdar://7886181
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101984 91177308-0d34-0410-b5e6-96231b3b80d8
FU per CPU arch to 32 per intinerary allowing precise modelling of quite
complex pipelines in the future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101754 91177308-0d34-0410-b5e6-96231b3b80d8
const_casts, and it reinforces the design of the Target classes being
immutable.
SelectionDAGISel::IsLegalToFold is now a static member function, because
PIC16 uses it in an unconventional way. There is more room for API
cleanup here.
And PIC16's AsmPrinter no longer uses TargetLowering.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101635 91177308-0d34-0410-b5e6-96231b3b80d8
When a target instruction wants to set target-specific flags, it should simply
set bits in the TSFlags bit vector defined in the Instruction TableGen class.
This works well because TableGen resolves member references late:
class I : Instruction {
AddrMode AM = AddrModeNone;
let TSFlags{3-0} = AM.Value;
}
let AM = AddrMode4 in
def ADD : I;
TSFlags gets the expected bits from AddrMode4 in this example.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100384 91177308-0d34-0410-b5e6-96231b3b80d8
which is really a property of the section being referenced.
Add a predicate to MCSection to replace it.
Yay for reduction in magic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100367 91177308-0d34-0410-b5e6-96231b3b80d8
"asm printering" happens through MCStreamer. This also
Streamerizes PIC16 debug info, which escaped my attention.
This removes a leak from LLVMTargetMachine of the 'legacy'
output stream.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100327 91177308-0d34-0410-b5e6-96231b3b80d8
Added support for address spaces and added a isVolatile field to memcpy, memmove, and memset,
e.g., llvm.memcpy.i32(i8*, i8*, i32, i32) -> llvm.memcpy.p0i8.p0i8.i32(i8*, i8*, i32, i32, i1)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100304 91177308-0d34-0410-b5e6-96231b3b80d8
Added support for address spaces and added a isVolatile field to memcpy, memmove, and memset,
e.g., llvm.memcpy.i32(i8*, i8*, i32, i32) -> llvm.memcpy.p0i8.p0i8.i32(i8*, i8*, i32, i32, i1)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100191 91177308-0d34-0410-b5e6-96231b3b80d8
- Do not try to infer GV alignment unless its type is sized. It's not possible to infer alignment if it has opaque type.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100118 91177308-0d34-0410-b5e6-96231b3b80d8
1. Makes it possible to lower with floating point loads and stores.
2. Avoid unaligned loads / stores unless it's fast.
3. Fix some memcpy lowering logic bug related to when to optimize a
load from constant string into a constant.
4. Adjust x86 memcpy lowering threshold to make it more sane.
5. Fix x86 target hook so it uses vector and floating point memory
ops more effectively.
rdar://7774704
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100090 91177308-0d34-0410-b5e6-96231b3b80d8
e.g., llvm.memcpy.i32(i8*, i8*, i32, i32) -> llvm.memcpy.p0i8.p0i8.i32(i8*, i8*, i32, i32, i1)
A update of langref will occur in a subsequent checkin.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99928 91177308-0d34-0410-b5e6-96231b3b80d8
create symbols. It is extremely error prone and a source of a lot
of the remaining integrated assembler bugs on x86-64.
This fixes rdar://7807601.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99902 91177308-0d34-0410-b5e6-96231b3b80d8
makes calls a little bit more consistent and allows easy removal of the
specializations in the future. Convert all callers to the templated functions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99838 91177308-0d34-0410-b5e6-96231b3b80d8
an MCSymbol. Make the EH_LABEL MachineInstr hold its label
with an MCSymbol instead of ID. Fix a bug in MMI.cpp which
would return labels named "Label4" instead of "label4".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98463 91177308-0d34-0410-b5e6-96231b3b80d8
instead of label ID's. This cleans up and regularizes a bunch
of code and makes way for future progress.
Unfortunately, this pointed out to me that JITDwarfEmitter.cpp
is largely copy and paste from DwarfException/MachineModuleInfo
and other places. This is very sad and disturbing. :(
One major change here is that TidyLandingPads moved from being
called in DwarfException::BeginFunction to being called in
DwarfException::EndFunction. There should not be any
functionality change from doing this, but I'm not an EH expert.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98459 91177308-0d34-0410-b5e6-96231b3b80d8
and passing off ownership to AsmPrinter. Now MachineModuleInfo
creates it and owns it by value. This allows us to use MCSymbols
more consistently throughout the rest of the code generator, and
simplifies a bit of code. This also allows MachineFunction to
keep an MCContext reference handy, and cleans up the TargetRegistry
interfaces for AsmPrinters.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98450 91177308-0d34-0410-b5e6-96231b3b80d8
LSDA into the TEXT section. We need to generate non-lazy pointers to it on
Mach-O. However, the object the NLP points to may be local to the translation
unit. If so, then the NLP needs to have the value of that object specified
instead of "0", which the linker interprets as "external".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98325 91177308-0d34-0410-b5e6-96231b3b80d8
indicates that an MCSymbol is external or not. (It's true if it's external.)
This will be used to specify the correct information to add to non-lazy
pointers. That will be explained further when this bit is used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98199 91177308-0d34-0410-b5e6-96231b3b80d8
is preparatory to having PEI's scavenged frame index value reuse logic
properly distinguish types of frame values (e.g., whether the value is
stack-pointer relative or frame-pointer relative).
No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98086 91177308-0d34-0410-b5e6-96231b3b80d8
Make it so. (This patch is in LowerCall_Darwin, which seems
to be used by SVR4 code as well; since that doesn't belong here,
I haven't worried about this case.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98077 91177308-0d34-0410-b5e6-96231b3b80d8
DoInstructionSelection. Inline "SelectRoot" into it from DAGISelHeader.
Sink some other stuff out of DAGISelHeader into SDISel.
Eliminate the various 'Indent' stuff from various targets, which dates
to when isel was recursive.
17 files changed, 114 insertions(+), 430 deletions(-)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97555 91177308-0d34-0410-b5e6-96231b3b80d8
but codegen'd differently. This really wanted to use some
sort of subreg to get the low 4 bytes of the G8RC register
or something. However, it's invalid and nothing is testing
it, so I'm just zapping the bogosity.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97345 91177308-0d34-0410-b5e6-96231b3b80d8
This is possible because F8RC is a subclass of F4RC. We keep FMRSD around so
fextend has a pattern.
Also allow folding of memory operands on FMRSD.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97275 91177308-0d34-0410-b5e6-96231b3b80d8
The PowerPC floating point registers can represent both f32 and f64 via the
two register classes F4RC and F8RC. F8RC is considered a subclass of F4RC to
allow cross-class coalescing. This coalescing only affects whether registers
are spilled as f32 or f64.
Spill slots must be accessed with load/store instructions corresponding to the
class of the spilled register. PPCInstrInfo::foldMemoryOperandImpl was looking
at the instruction opcode which is wrong.
X86 has similar floating point register classes, but doesn't try to fold
memory operands, so there is no problem there.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97262 91177308-0d34-0410-b5e6-96231b3b80d8
stack frame, the prolog/epilog code was using the same
register for the copy of CR and the address of the save slot. Oops.
This is fixed here for Darwin, sort of, by reserving R2 for this case.
A better way would be to do the store before the decrement of SP,
which is safe on Darwin due to the red zone.
SVR4 probably has the same problem, but I don't know how to fix it;
there is no red zone and R2 is already used for something else.
I'm going to leave it to someone interested in that target.
Better still would be to rewrite the CR-saving code completely;
spilling each CR subregister individually is horrible code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96015 91177308-0d34-0410-b5e6-96231b3b80d8
into TargetOpcodes.h. #include the new TargetOpcodes.h
into MachineInstr. Add new inline accessors (like isPHI())
to MachineInstr, and start using them throughout the
codebase.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95687 91177308-0d34-0410-b5e6-96231b3b80d8
the end of the instruction instead of expecting the caller to
do it. This currently causes the asm-verbose instruction
comments to be on the next line.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95178 91177308-0d34-0410-b5e6-96231b3b80d8
mccontext instead of having AsmPrinter do it. This allows other
types of MCStreamer's to be passed in.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95155 91177308-0d34-0410-b5e6-96231b3b80d8
eliminate random "code emitter" stuff in Alpha, except for
the JIT path. Next up, remove the template cruft.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95131 91177308-0d34-0410-b5e6-96231b3b80d8
runOnMachineFunction, and switch PPC to use EmitFunctionBody.
The two ppc asmprinters now don't heave to define
runOnMachineFunction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94722 91177308-0d34-0410-b5e6-96231b3b80d8
Move the X86 implementation of function body emission up to
AsmPrinter::EmitFunctionBody, which works by calling the virtual
EmitInstruction method.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94716 91177308-0d34-0410-b5e6-96231b3b80d8
Modules and ModuleProviders. Because the "ModuleProvider" simply materializes
GlobalValues now, and doesn't provide modules, it's renamed to
"GVMaterializer". Code that used to need a ModuleProvider to materialize
Functions can now materialize the Functions directly. Functions no longer use a
magic linkage to record that they're materializable; they simply ask the
GVMaterializer.
Because the C ABI must never change, we can't remove LLVMModuleProviderRef or
the functions that refer to it. Instead, because Module now exposes the same
functionality ModuleProvider used to, we store a Module* in any
LLVMModuleProviderRef and translate in the wrapper methods. The bindings to
other languages still use the ModuleProvider concept. It would probably be
worth some time to update them to follow the C++ more closely, but I don't
intend to do it.
Fixes http://llvm.org/PR5737 and http://llvm.org/PR5735.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94686 91177308-0d34-0410-b5e6-96231b3b80d8
which allows targets to override function entry label emission.
Use it to convert linux/ppc to use EmitFunctionHeader().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94667 91177308-0d34-0410-b5e6-96231b3b80d8
Target independent isel should always pass along the "tail call" property. Change
target hook LowerCall's parameter "isTailCall" into a refernce. If the target
decides it's impossible to honor the tail call request, it should set isTailCall
to false to make target independent isel happy.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94626 91177308-0d34-0410-b5e6-96231b3b80d8
Default HasSetDirective to true, since most targets have it.
The targets that claim to not have it probably do, or it is
spelled differently. These include Blackfin, Mips, Alpha, and
PIC16. All of these except pic16 are normal ELF targets, so
they almost certainly have it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94585 91177308-0d34-0410-b5e6-96231b3b80d8
AsmPrinter::SetupMachineFunction sets it. Note that systemz
and msp430 didn't. Yay for reduced inconsistency! :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94510 91177308-0d34-0410-b5e6-96231b3b80d8
It looks like linux/arm and linux/mips have the same setting, which
are probably wrong. Someone who cares about ARM and MIPS should
investigate with the testcase in PR6129.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94381 91177308-0d34-0410-b5e6-96231b3b80d8
"sext cond" instead of a select. This simplifies some instcombine
code, matches the policy for zext (cond ? 1 : 0 -> zext), and allows
us to generate better code for a testcase on ppc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94339 91177308-0d34-0410-b5e6-96231b3b80d8
missing ones are libsupport, libsystem and libvmcore. libvmcore is
currently blocked on bugpoint, which uses EH. Once it stops using
EH, we can switch it off.
This #if 0's out 3 unit tests, because gtest requires RTTI information.
Suggestions welcome on how to fix this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94164 91177308-0d34-0410-b5e6-96231b3b80d8
MachineModuleInfoMachO instead. This eliminates two sources
of nondeterministic output in the ppc backend, but function
stubs are still bad.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94029 91177308-0d34-0410-b5e6-96231b3b80d8
I really want clients of the streamer to be able to say "emit this
64-bit integer" and have it get broken down right by the streamer.
I may change this in the future, we'll see how it works out.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93934 91177308-0d34-0410-b5e6-96231b3b80d8
doing global variable classification anymore) and hookized, sink almost
all target targets global variable emission code into AsmPrinter and out
of each target.
Some notes:
1. PIC16 does completely custom and crazy stuff, so it is not changed.
2. XCore has some custom handling for extra directives. I'll look at it next.
3. This switches linux/ppc to use .globl instead of .global. If .globl is
actually wrong, let me know and I'll fix it.
4. This makes linux/ppc get a lot of random cases right which were obviously
wrong before, it is probably now a bit healthier.
5. Blackfin will probably start getting .comm and other things that it didn't
before. If this is undesirable, it should explicitly opt out of these
things by clearing the relevant fields of MCAsmInfo.
This leads to a nice diffstat:
14 files changed, 127 insertions(+), 830 deletions(-)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93858 91177308-0d34-0410-b5e6-96231b3b80d8
This makes a similar code dead in all the other targets, I'll clean it up
in a bit.
This also moves handling of lcomm up before acquisition of a section,
since lcomm never needs a section.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93851 91177308-0d34-0410-b5e6-96231b3b80d8
simplify and commonize some of the asmprinter logic for globals.
This also avoids printing the MCSection for .zerofill, which broke
the llvm-gcc build.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93843 91177308-0d34-0410-b5e6-96231b3b80d8
1. TargetLoweringObjectFileMachO should decide if something
goes in zerofill instead of having every target do it.
2. TargetLoweringObjectFileMachO should assign said symbols to
the right MCSection, the asmprinters should just emit to the
right section.
3. Since all zerofill stuff goes through mcstreamer anymore,
MAI can have a bool "haszerofill" instead of having the textual
directive to emit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93838 91177308-0d34-0410-b5e6-96231b3b80d8
remove it and change all the code that prints MCSymbols to use
<< instead, which is much simpler and cleaner.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93695 91177308-0d34-0410-b5e6-96231b3b80d8
and add an explicit ForcePrivate argument.
Switch FunctionEHFrameInfo to be MCSymbol based instead of string based.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93646 91177308-0d34-0410-b5e6-96231b3b80d8
instead of returning it in an std::string. Based on this change:
1. Change TargetLoweringObjectFileCOFF::getCOFFSection to take a StringRef
2. Change a bunch of targets to call makeNameProper with a smallstring,
making several of them *much* more efficient.
3. Rewrite Mangler::makeNameProper to not build names and then prepend
prefixes, not use temporary std::strings, and to avoid other crimes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93298 91177308-0d34-0410-b5e6-96231b3b80d8
It is enough to give the super registers CR0, CR1, ..., and specifying the
sub-registers as well causes confusion in the liveness computations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92778 91177308-0d34-0410-b5e6-96231b3b80d8
clear what information these functions are actually using.
This is also a micro-optimization, as passing a SDNode * around is
simpler than passing a { SDNode *, int } by value or reference.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92564 91177308-0d34-0410-b5e6-96231b3b80d8
return partial registers. This affected the back-end lowering code some.
Also patch up some places I missed before in the "get" functions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91880 91177308-0d34-0410-b5e6-96231b3b80d8
remove start/finishGVStub and the BufferState helper class from the
MachineCodeEmitter interface. It has the side-effect of not setting the
indirect global writable and then executable on ARM, but that shouldn't be
necessary.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91464 91177308-0d34-0410-b5e6-96231b3b80d8
for all the processors where I have tried it, and even when it might not help
performance, the cost is quite low. The opportunities for duplicating
indirect branches are limited by other factors so code size does not change
much due to tail duplicating indirect branches aggressively.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90144 91177308-0d34-0410-b5e6-96231b3b80d8
With the testcase for pr3120, the "threaded interpreter" runtime decreases
from 1788 to 1413 with this change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89877 91177308-0d34-0410-b5e6-96231b3b80d8
This violates the ABI (that area is "reserved"), and
while it is safe if all code is generated with current
compilers, there is some very old code around that uses
that slot for something else, and breaks if it is stored
into. Adjust testcases looking for current behavior.
I've verified that the stack frame size is right in all
testcases, whether it changed or not. 7311323.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89811 91177308-0d34-0410-b5e6-96231b3b80d8
way for each TargetJITInfo subclass to allocate its own stubs. This
means stubs aren't as exactly-sized anymore, but it lets us get rid of
TargetJITInfo::emitFunctionStubAtAddr(), which lets ARM and PPC
support the eager JIT, fixing http://llvm.org/PR4816.
* Rename the JITEmitter's stub creation functions to describe the kind
of stub they create. So far, all of them create lazy-compilation
stubs, but they sometimes get used when far-call stubs are needed.
Fixing http://llvm.org/PR5201 will involve fixing this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89715 91177308-0d34-0410-b5e6-96231b3b80d8
Note that "hasDotLocAndDotFile"-style debug info was already broken;
people wanting this functionality should implement it in the
AsmPrinter/DwarfWriter code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89711 91177308-0d34-0410-b5e6-96231b3b80d8
It's probably better in the long run to replace the
indirect-GlobalVariable system. That'll be done after a subsequent
patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89708 91177308-0d34-0410-b5e6-96231b3b80d8
target-specific AsmPrinters. Not all comments need DebugInfo.
Re-enable the line numbers comment test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@88697 91177308-0d34-0410-b5e6-96231b3b80d8
slots. The AsmPrinter will use this information to determine whether to
print a spill/reload comment.
Remove default argument values. It's too easy to pass a wrong argument
value when multiple arguments have default values. Make everything
explicit to trap bugs early.
Update all targets to adhere to the new interfaces..
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@87022 91177308-0d34-0410-b5e6-96231b3b80d8
generates a sequence similar to this:
__Z4funci:
LFB2:
mflr r0
LCFI0:
stmw r30,-8(r1)
LCFI1:
stw r0,8(r1)
LCFI2:
stwu r1,-80(r1)
LCFI3:
mr r30,r1
LCFI4:
where LCFI3 and LCFI4 are used by the FDE to indicate what the FP, LR, and other
things are. We generated something more like this:
Leh_func_begin1:
mflr r0
stw r31, 20(r1)
stw r0, 8(r1)
Llabel1:
stwu r1, -80(r1)
Llabel2:
mr r31, r1
Note that we are missing the "mr" instruction. This patch makes it more like the
GCC output.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86729 91177308-0d34-0410-b5e6-96231b3b80d8
was generated. This caused code like this:
## The asm code for the function
.section __TEXT,__const
.align 2
lJTI11_0:
LJTI11_0:
.long LBB11_16
.long LBB11_4
.long LBB11_5
.long LBB11_6
.long LBB11_7
.long LBB11_8
.long LBB11_9
.long LBB11_10
.long LBB11_11
.long LBB11_12
.long LBB11_13
.long LBB11_14
Leh_func_end11: ## <---now in the wrong section!
The `Leh_func_end11' would then end up in the wrong section, causing the
resulting EH frame information to be wrong:
__ZL11CheckRightsjPKcbRbRP6NSData.eh:
.set Lset500eh,Leh_frame_end11-Leh_frame_begin11
.long Lset500eh ; Length of Frame Information Entry
Leh_frame_begin11:
.long Leh_frame_begin11-Leh_frame_common
.long Leh_func_begin11-.
.set Lset501eh,Leh_func_end11-Leh_func_begin11
.long Lset501eh ; FDE address range
`Lset501eh' is now something huge instead of the real value.
The X86 back-end generates the jump table after the EH information is
emitted. Do the same here.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86588 91177308-0d34-0410-b5e6-96231b3b80d8
bunch of associated comments, because it doesn't have anything to do
with DAGs or scheduling. This is another step in decoupling MachineInstr
emitting from scheduling.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85517 91177308-0d34-0410-b5e6-96231b3b80d8
Chris claims we should never have visibility_hidden inside any .cpp file but
that's still not true even after this commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85042 91177308-0d34-0410-b5e6-96231b3b80d8
stack slots and giving them different PseudoSourceValue's did not fix the
problem of post-alloc scheduling miscompiling llvm itself.
- Apply Dan's conservative workaround by assuming any non fixed stack slots can
alias other memory locations. This means a load from spill slot #1 cannot
move above a store of spill slot #2.
- Enable post-alloc scheduling for x86 at optimization leverl Default and above.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84424 91177308-0d34-0410-b5e6-96231b3b80d8
