There were a few places where kill flags were not being set correctly, and
where 32-bit instruction variants were being used with 64-bit registers. After
r178180, this code was being triggered causing llc to assert.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178220 91177308-0d34-0410-b5e6-96231b3b80d8
form of call in preference to memory indirect on Atom.
In this case, the patch applies the optimization to the code for reloading
spilled registers.
The patch also includes changes to sibcall.ll and movgs.ll, which were
failing on the Atom buildbot after the first patch was applied.
This patch by Sriram Murali.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178193 91177308-0d34-0410-b5e6-96231b3b80d8
These functions should have the same list of load/store instructions. Now that
all load/store forms have been normalized (to single instructions or pseudos)
they can be resynchronized.
Found by inspection, although hopefully this will improve optimization. I've
also added some comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178180 91177308-0d34-0410-b5e6-96231b3b80d8
indirect through a memory address is to load the memory address into
a register and then call indirect through the register.
This patch implements this improvement by modifying SelectionDAG to
force a function address which is a memory reference to be loaded
into a virtual register.
Patch by Sriram Murali.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178171 91177308-0d34-0410-b5e6-96231b3b80d8
6 more piglit tests.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178145 91177308-0d34-0410-b5e6-96231b3b80d8
It seems that the Darwin PPC assembler requires r0 to be written as 0 when it
means 0 (at least in lwarx/stwcx.). Fixes PR15605.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178142 91177308-0d34-0410-b5e6-96231b3b80d8
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Tested-by: Michel Dänzer <michel.daenzer@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178127 91177308-0d34-0410-b5e6-96231b3b80d8
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Tested-by: Michel Dänzer <michel.daenzer@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178126 91177308-0d34-0410-b5e6-96231b3b80d8
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Tested-by: Michel Dänzer <michel.daenzer@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178125 91177308-0d34-0410-b5e6-96231b3b80d8
The R0 register can now be allocated because instructions
that cannot use R0 as a GPR have been appropriately marked.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178123 91177308-0d34-0410-b5e6-96231b3b80d8
The register parameter in these instructions becomes the base register in an
r+i ld instruction (and, thus, cannot be r0).
This is not yet testable because we don't yet allocate r0 (and even then any
test would be very fragile).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178121 91177308-0d34-0410-b5e6-96231b3b80d8
Either operand of these pseudo instructions can be transformed into the first
operand of an isel instruction (and this operand cannot be r0).
This is not yet testable because we don't yet allocate r0 (and even when we do,
any test would be very fragile).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178119 91177308-0d34-0410-b5e6-96231b3b80d8
Like the addi/addis instructions themselves, these pseudo instructions also
cannot have r0 as their register parameter (because it will be interpreted as
the value 0).
This is not yet testable because we don't yet allocate r0 (and even when we do,
any regression test would be very fragile because it would depend on the
register allocator heuristics).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178118 91177308-0d34-0410-b5e6-96231b3b80d8
Some implementation detail in the forgotten past required the link
register to be placed in the GPRC and G8RC register classes. This is
just wrong on the face of it, and causes several extra intersection
register classes to be generated. I found this was having evil
effects on instruction scheduling, by causing the wrong register class
to be consulted for register pressure decisions.
No code generation changes are expected, other than some minor changes
in instruction order. Seven tests in the test bucket required minor
tweaks to adjust to the new normal.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178114 91177308-0d34-0410-b5e6-96231b3b80d8
As Bill Schmidt pointed out to me, only on Darwin do we need to spill/restore
VRSAVE in the SjLj code. For non-Darwin, don't spill/restore VRSAVE (and I've
added some asserts to make sure that we're not).
As it turns out, we're not currently handling the Darwin case correctly (I've
added a FIXME in the test case). I've tried adding various implied register
definitions/uses to force the spill without success, so I'll need to address
this later.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178096 91177308-0d34-0410-b5e6-96231b3b80d8
All Intel CPUs since Yonah look a lot alike, at least at the granularity
of the scheduling models. We can add more accurate models for
processors that aren't Sandy Bridge if required. Haswell will probably
need its own.
The Atom processor and anything based on NetBurst is completely
different. So are the non-Intel chips.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178080 91177308-0d34-0410-b5e6-96231b3b80d8
As suggested by Bill Schmidt (in reviewing r178067), use the real register
number bit lengths (which is self-documenting, and prevents using illegal
numbers), and set only the relevant bits in HWEncoding (which defaults to 0).
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178077 91177308-0d34-0410-b5e6-96231b3b80d8
As pointed out by Jakob, we don't need to maintain a separate
register-numbering table. Instead we should let TableGen generate the table for
us from the information (already present) in PPCRegisterInfo.td.
TRI->getEncodingValue is now used to access register-encoding values.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178067 91177308-0d34-0410-b5e6-96231b3b80d8
Now that the register scavenger can support multiple spill slots, and PEI can
use virtual-register-based scavenging for multiple simultaneous registers, we
can use a virtual register for the transfer register in the CR spilling code.
This should eliminate the last place (outside of the prologue/epilogue) where
we depend on the unconditional availability of the r0 register. We will soon be
able to allocate it (in a somewhat restricted sense) as a GPR.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178060 91177308-0d34-0410-b5e6-96231b3b80d8
PPC's use of PEI's virtual-register-based scavenging functionality had
redefined the virtual registers (it was non-SSA). Now that PEI supports
dealing with instructions with multiple virtual registers, this can be
cleanup up to use multiple virtual registers and keep SSA form.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178059 91177308-0d34-0410-b5e6-96231b3b80d8
Now all x86 instructions that have itinerary classes also have SchedRW
lists. This is required before the new scheduling models can be used.
There are still unannotated instructions remaining, but they don't have
itinerary classes either.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178051 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r177968. It is causing failures in a local build bot.
"fatal error: error in backend: Expected a variant SchedClass"
Original commit message:
Move the CortexA9 resources into the CortexA9 SchedModel namespace. Define
resource mappings under the CortexA9 SchedModel. Define resources and mappings
for the SwiftModel.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178028 91177308-0d34-0410-b5e6-96231b3b80d8
Not only fold immediates, but avoid unnecessary copies as well.
Signed-off-by: Christian König <christian.koenig@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178024 91177308-0d34-0410-b5e6-96231b3b80d8
Just define the address as unknown instead of VReg_32.
Signed-off-by: Christian König <christian.koenig@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178022 91177308-0d34-0410-b5e6-96231b3b80d8
They read from constant register space anyway.
v2: fix lit tests
Signed-off-by: Christian König <christian.koenig@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178020 91177308-0d34-0410-b5e6-96231b3b80d8
Just enable WQM when we see an LDS interpolation instruction.
Signed-off-by: Christian König <christian.koenig@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178019 91177308-0d34-0410-b5e6-96231b3b80d8
Restore the EXEC mask early, otherwise a copy might end up not beeing executed.
Candidate for the mesa stable branch.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Tested-by: Michel Dänzer <michel.daenzer@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178018 91177308-0d34-0410-b5e6-96231b3b80d8
If PC or SP is the destination, the disassembler erroneously failed with the
invalid encoding, despite the manual saying that both are fine.
This patch addresses failure to decode encoding T4 of LDR (A8.8.62) which is a
postindexed load, where the offset 0xc is applied to SP after the load occurs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178017 91177308-0d34-0410-b5e6-96231b3b80d8
There remain a number of patterns that cannot (and should not)
be handled by the asm parser, in particular all the Pseudo patterns.
This commit marks those patterns as isCodeGenOnly.
No change in generated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178008 91177308-0d34-0410-b5e6-96231b3b80d8
MCTargetDesc/PPCMCCodeEmitter.cpp current has code like:
if (isSVR4ABI() && is64BitMode())
Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_toc16));
else
Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_lo16));
This is a problem for the asm parser, since it requires knowledge of
the ABI / 64-bit mode to be set up. However, more fundamentally,
at this point we shouldn't make such distinctions anyway; in an assembler
file, it always ought to be possible to e.g. generate TOC relocations even
when the main ABI is one that doesn't use TOC.
Fortunately, this is actually completely unnecessary; that code was added
to decide whether to generate TOC relocations, but that information is in
fact already encoded in the VariantKind of the underlying symbol.
This commit therefore merges those fixup types into one, and then decides
which relocation to use based on the VariantKind.
No changes in generated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178007 91177308-0d34-0410-b5e6-96231b3b80d8
As part of the the sequence generated to implement long double -> int
conversions, we need to perform an FADD in round-to-zero mode. This is
problematical since the FPSCR is not at all modeled at the SelectionDAG
level, and thus there is a risk of getting floating point instructions
generated out of sequence with the instructions to modify FPSCR.
The current code handles this by somewhat "special" patterns that in part
have dummy operands, and/or duplicate existing instructions, making them
awkward to handle in the asm parser.
This commit changes this by leaving the "FADD in round-to-zero mode"
as an atomic operation on the SelectionDAG level, and only split it up into
real instructions at the MI level (via custom inserter). Since at *this*
level the FPSCR *is* modeled (via the "RM" hard register), much of the
"special" stuff can just go away, and the resulting patterns can be used by
the asm parser.
No significant change in generated code expected.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178006 91177308-0d34-0410-b5e6-96231b3b80d8
The LDrs pattern is a duplicate of LD, except that it accepts memory
addresses where the displacement is a symbolLo64. An operand type
"memrs" is defined for just that purpose.
However, this wouldn't be necessary if the default "memrix" operand
type were to simply accept 64-bit symbolic addresses directly.
The only problem with that is that it uses "symbolLo", which is
hardcoded to 32-bit.
To fix this, this commit changes "memri" and "memrix" to use new
operand types for the memory displacement, which allow iPTR
instead of i32. This will also make address parsing easier to
implment in the asm parser.
No change in generated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178005 91177308-0d34-0410-b5e6-96231b3b80d8
The ADDI/ADDI8 patterns are currently duplicated into ADDIL/ADDI8L,
which describe the same instruction, except that they accept a
symbolLo[64] operand instead of a s16imm[64] operand.
This duplication confuses the asm parser, and it actually not really
needed, since symbolLo[64] already accepts immediate operands anyway.
So this commit removes the duplicate patterns.
No change in generated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178004 91177308-0d34-0410-b5e6-96231b3b80d8
This commit changes the ISEL patterns to use a CCBITRC operand
instead of a "pred" operand. This matches the actual instruction
text more directly, and simplifies use of ISEL with the asm parser.
In addition, this change allows some simplification of handling
the "pred" operand, as this is now only used by BCC.
No change in generated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178003 91177308-0d34-0410-b5e6-96231b3b80d8
The BLR pattern cannot be recognized by the asm parser in its current form.
This complexity is due to an apparent attempt to enable conditional BLR
variants. However, none of those can ever be generated by current code;
the pattern is only ever created using the default "pred" operand.
To simplify the pattern and allow it to be recognized by the parser,
this commit removes those attempts at conditional BLR support.
When we later come back to actually add real conditional BLR, this
should probably be done via a fully generic conditional branch pattern.
No change in generated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178002 91177308-0d34-0410-b5e6-96231b3b80d8
In PPCInstr64Bit.td, some branch patterns appear in a different sequence
than the corresponding 32-bit patterns in PPCInstrInfo.td.
To simplify future changes that affect both files, this commit moves
those patterns to rearrange them into a similar sequence.
No effect on generated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178001 91177308-0d34-0410-b5e6-96231b3b80d8
Use a MapVector on types where the iteration order matters.
Otherwise we doesn't always produce a deterministic output.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177999 91177308-0d34-0410-b5e6-96231b3b80d8
Move the CortexA9 resources into the CortexA9 SchedModel namespace. Define
resource mappings under the CortexA9 SchedModel. Define resources and mappings
for the SwiftModel.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177968 91177308-0d34-0410-b5e6-96231b3b80d8
This is very much work in progress. Please send me a note if you start to depend
on the added abstract read/write resources. They are subject to change until
further notice.
The old itinerary is still the default.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177967 91177308-0d34-0410-b5e6-96231b3b80d8
- It's still considered aligned when the specified alignment is larger
than the natural alignment;
- The new alignment for the high 128-bit vector should be min(16,
alignment) as the pointer is advanced by 16, a power-of-2 offset.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177947 91177308-0d34-0410-b5e6-96231b3b80d8
All the instructions tagged with IIC_DEFAULT had nothing in common, and
we already have a NoItineraries class to represent untagged
instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177937 91177308-0d34-0410-b5e6-96231b3b80d8
This commit updates the PowerPC back-end (PPCInstrInfo.td and
PPCInstr64Bit.td) to use types instead of register classes in
instruction patterns, along the lines of Jakob Stoklund Olesen's
changes in r177835 for Sparc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177890 91177308-0d34-0410-b5e6-96231b3b80d8
This commit updates the PowerPC back-end (PPCInstrInfo.td and
PPCInstr64Bit.td) to use types instead of register classes in
Pat patterns, along the lines of Jakob Stoklund Olesen's
changes in r177829 for Sparc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177889 91177308-0d34-0410-b5e6-96231b3b80d8
sure the base register and would-be writeback register don't conflict for
stores. This was already being done for loads.
Unfortunately, it is rather difficult to create a test case for this issue. It
was exposed in 450.soplex at LTO and requires unlucky register allocation.
<rdar://13394908>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177874 91177308-0d34-0410-b5e6-96231b3b80d8
Also update the documentation since Sparc is the nicest backend, and
used as an example in WritingAnLLVMBackend.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177835 91177308-0d34-0410-b5e6-96231b3b80d8
In order for the new ZERO register to be used with MC, etc. we need to specify
its register number (0).
Thanks to Kai for reporting the problem!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177833 91177308-0d34-0410-b5e6-96231b3b80d8
In preparation for using the new register scavenger capability for providing
more than one register simultaneously, specifically note functions that have
spilled VRSAVE (currently, this can happen only in functions that use the
setjmp intrinsic). As with CR spilling, such functions will need to provide two
emergency spill slots to the scavenger.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177832 91177308-0d34-0410-b5e6-96231b3b80d8
I recently added a BCL instruction definition as part of implementing SjLj
support. This can also be used to MCize bcl emission in the asm printer.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177830 91177308-0d34-0410-b5e6-96231b3b80d8
The SelectionDAG graph has MVT type labels, not register classes, so
this makes it clearer what is happening.
This notation is also robust against adding more types to the IntRegs
register class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177829 91177308-0d34-0410-b5e6-96231b3b80d8
These spilling functions will eventually make use of the register scavenger,
however, they'll do so by taking advantage of PEI's virtual-register-based
delayed scavenging mechanism. As a result, these function parameters will not
be used, and can be removed.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177827 91177308-0d34-0410-b5e6-96231b3b80d8
The LR register is unconditionally reserved, and its spilling and restoration
is handled by the prologue/epilogue code. As a result, it is never explicitly
spilled by the register allocator.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177823 91177308-0d34-0410-b5e6-96231b3b80d8
This patch lets the register scavenger make use of multiple spill slots in
order to guarantee that it will be able to provide multiple registers
simultaneously.
To support this, the RS's API has changed slightly: setScavengingFrameIndex /
getScavengingFrameIndex have been replaced by addScavengingFrameIndex /
isScavengingFrameIndex / getScavengingFrameIndices.
In forthcoming commits, the PowerPC backend will use this capability in order
to implement the spilling of condition registers, and some special-purpose
registers, without relying on r0 being reserved. In some cases, spilling these
registers requires two GPRs: one for addressing and one to hold the value being
transferred.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177774 91177308-0d34-0410-b5e6-96231b3b80d8
We currently have a duplicated set of call instruction patterns depending
on the ABI to be followed (Darwin vs. Linux). This is a bit odd; while the
different ABIs will result in different instruction sequences, the actual
instructions themselves ought to be independent of the ABI. And in fact it
turns out that the only nontrivial difference between the two sets of
patterns is that in the PPC64 Linux ABI, the instruction used for indirect
calls is marked to take X11 as extra input register (which is indeed used
only with that ABI to hold an incoming environment pointer for nested
functions). However, this does not need to be hard-coded at the .td
pattern level; instead, the C++ code expanding calls can simply add that
use, just like it adds uses for argument registers anyway.
No change in generated code expected.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177735 91177308-0d34-0410-b5e6-96231b3b80d8
Currently, the sub-operand of a memrr address that corresponds to what
hardware considers the base register is called "offreg", while the
sub-operand that corresponds to the offset is called "ptrreg".
To avoid confusion, this patch simply swaps the named of those two
sub-operands and updates all uses. No functional change is intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177734 91177308-0d34-0410-b5e6-96231b3b80d8
PPCTargetLowering::getPreIndexedAddressParts currently provides
the base part of a memory address in the offset result, and the
offset part in the base result. That swap is then undone again
when an MI instruction is generated (in PPCDAGToDAGISel::Select
for loads, and using .md Pat patterns for stores).
This patch reverts this double swap, to make common code and
back-end be in sync as to which part of the address is base
and which is offset.
To avoid performance regressions in certain cases, target code
now checks whether the choice of base register would be rejected
for pre-inc accesses by common code, and attempts to swap base
and offset again in such cases. (Overall, this means that now
pre-ice accesses are generated *more* frequently than before.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177733 91177308-0d34-0410-b5e6-96231b3b80d8
The iaddroff ComplexPattern is supposed to recognize displacement
expressions that have been processed by a SelectAddressRegImm,
which means it needs to accept TargetConstant and TargetGlobalAddress
nodes. Currently, it erroneously also accepts some other nodes,
in particular Constant and PPCISD::Lo.
While this problem is currently latent, it would cause wrong-code
bugs with a follow-on patch I'm about to commit, so this patch
tightens the ComplexPattern. The equivalent change is made in
PPCDAGToDAGISel::Select, where pre-inc load patterns are handled
(as opposed to store patterns, the loads are handled in C++ code
without making use of the .td ComplexPattern).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177732 91177308-0d34-0410-b5e6-96231b3b80d8
The xaddroff pattern is currently (mistakenly) used to recognize
the *base* register in pre-inc store patterns. This patch replaces
those uses by ptr_rc_nor0 (as is elsewhere done to match the base
register of an address), and removes the now unused ComplexPattern.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177731 91177308-0d34-0410-b5e6-96231b3b80d8
For mips a branch an 18-bit signed offset (the 16-bit
offset field shifted left 2 bits) is added to the
address of the instruction following the branch
(not the branch itself), in the branch delay slot,
to form a PC-relative effective target address.
Previously, the code generator did not perform the
shift of the immediate branch offset which resulted
in wrong instruction opcode. This patch fixes the issue.
Contributor: Vladimir Medic
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177687 91177308-0d34-0410-b5e6-96231b3b80d8
This patch uses the generated instruction info tables to
identify memory/load store instructions.
After successful matching and based on the operand type
and size, it generates additional instructions to the output.
Contributor: Vladimir Medic
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177685 91177308-0d34-0410-b5e6-96231b3b80d8
As Jakob pointed out in his review of r177423, having a shared ZERO
register between the 32- and 64-bit register classes causes this
odd G8RC_NOX0_and_GPRC_NOR0 class to be created. As recommended,
this adds a ZERO8 register which differentiates the 32- and 64-bit
zeros.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177683 91177308-0d34-0410-b5e6-96231b3b80d8
Thanks to Jakob for isolating the underlying problem from the
test case in r177423. The original commit had introduced
asymmetric copy operations, but these turned out to be a work-around
to the real problem (the use of == instead of hasSubClassEq in PPCCTRLoops).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177679 91177308-0d34-0410-b5e6-96231b3b80d8
The .set directive in the Mips the assembler can be
used to set the value of a symbol to an expression.
This changes the symbol's value and type to conform
to the expression's.
Syntax: .set symbol, expression
This patch implements the parsing of the above syntax
and enables the parser to use defined symbols when
parsing operands.
Contributor: Vladimir Medic
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177667 91177308-0d34-0410-b5e6-96231b3b80d8
This implements SJLJ lowering on PPC, making the Clang functions
__builtin_{setjmp/longjmp} functional on PPC platforms. The implementation
strategy is similar to that on X86, with the exception that a branch-and-link
variant is used to get the right jump address. Credit goes to Bill Schmidt for
suggesting the use of the unconditional bcl form (instead of the regular bl
instruction) to limit return-address-cache pollution.
Benchmarking the speed at -O3 of:
static jmp_buf env_sigill;
void foo() {
__builtin_longjmp(env_sigill,1);
}
main() {
...
for (int i = 0; i < c; ++i) {
if (__builtin_setjmp(env_sigill)) {
goto done;
} else {
foo();
}
done:;
}
...
}
vs. the same code using the libc setjmp/longjmp functions on a P7 shows that
this builtin implementation is ~4x faster with Altivec enabled and ~7.25x
faster with Altivec disabled. This comparison is somewhat unfair because the
libc version must also save/restore the VSX registers which we don't yet
support.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177666 91177308-0d34-0410-b5e6-96231b3b80d8
Although there is only one Altivec VRSAVE register, it is a member of
a register class, and we need the ability to spill it. Because this
register is normally callee-preserved and handled by special code this
has never before been necessary. However, this capability will be required by
a forthcoming commit adding SjLj support.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177654 91177308-0d34-0410-b5e6-96231b3b80d8
The old code used to lower FRAMEADDR tried to replicate the logic in the real
frame-lowering code that determines whether or not the frame pointer (r31) will
be used. When it seemed as through the frame pointer would not be used, the
stack pointer (r1) was used instead. Unfortunately, because the stack size is
not yet known, this does not work. Instead, this change introduces new
always-reserved pseudo-registers (FP and FP8) that are replaced during prologue
insertion with the real frame-pointer register (either r1 or r31).
It is important that this intrinsic always return a valid frame address because
it is used by Clang to store the frame address as part of code generation for
__builtin_setjmp.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177653 91177308-0d34-0410-b5e6-96231b3b80d8
NEON is not IEEE 754 compliant, so we should avoid lowering single-precision
floating point operations with NEON unless unsafe-math is turned on. The
equivalent VFP instructions are IEEE 754 compliant, but in some cores they're
much slower, so some archs/OSs might still request it to be on by default,
such as Swift and Darwin.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177651 91177308-0d34-0410-b5e6-96231b3b80d8
- After moving logic recognizing vector shift with scalar amount from
DAG combining into DAG lowering, we declare to customize all vector
shifts even vector shift on AVX is legal. As a result, the cost model
needs special tuning to identify these legal cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177586 91177308-0d34-0410-b5e6-96231b3b80d8
- Move SRA/SRL/SHL lowering support from DAG combination to DAG lowering
to support extended 256-bit integer in AVX but not AVX2.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177478 91177308-0d34-0410-b5e6-96231b3b80d8
Add a new WriteZero SchedWrite type for the common dependency-breaking
instructions that clear a register.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177442 91177308-0d34-0410-b5e6-96231b3b80d8
an X86Operand, but also performs a Sema lookup and adds the sizing directive
when appropriate. Use this when parsing a bracketed statement. This is
necessary to get the instruction matching correct as well. Test case coming
on clang side.
rdar://13455408
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177439 91177308-0d34-0410-b5e6-96231b3b80d8
All pre-increment load patterns need to set the mayLoad flag (since
they don't provide a DAG pattern).
This was missing for LHAUX8 and LWAUX, which is added by this patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177431 91177308-0d34-0410-b5e6-96231b3b80d8
As opposed to to pre-increment store patterns, the pre-increment
load patterns were already using standard memory operands, with
the sole exception of LHAU8.
As there's no real reason why LHAU8 should be different here,
this patch simply rewrites the pattern to also use a memri
operand, just like all the other patterns.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177430 91177308-0d34-0410-b5e6-96231b3b80d8
Currently, pre-increment store patterns are written to use two separate
operands to represent address base and displacement:
stwu $rS, $ptroff($ptrreg)
This causes problems when implementing the assembler parser, so this
commit changes the patterns to use standard (complex) memory operands
like in all other memory access instruction patterns:
stwu $rS, $dst
To still match those instructions against the appropriate pre_store
SelectionDAG nodes, the patch uses the new feature that allows a Pat
to match multiple DAG operands against a single (complex) instruction
operand.
Approved by Hal Finkel.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177429 91177308-0d34-0410-b5e6-96231b3b80d8
The tocentry operand class refers to 64-bit values (it is only used in 64-bit,
where iPTR is a 64-bit type), but its sole suboperand is designated as 32-bit
type. This causes a mismatch to be detected at compile-time with the TableGen
patch I'll check in shortly.
To fix this, this commit changes the suboperand to a 64-bit type as well.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177427 91177308-0d34-0410-b5e6-96231b3b80d8
def : Pat<(load (i64 (X86Wrapper tglobaltlsaddr :$dst))),
(MOV64rm tglobaltlsaddr :$dst)>;
This pattern is invalid because the MOV64rm instruction expects a
source operand of type "i64mem", which is a subclass of X86MemOperand
and thus actually consists of five MI operands, but the Pat provides
only a single MI operand ("tglobaltlsaddr" matches an SDnode of
type ISD::TargetGlobalTLSAddress and provides a single output).
Thus, if the pattern were ever matched, subsequent uses of the MOV64rm
instruction pattern would access uninitialized memory. In addition,
with the TableGen patch I'm about to check in, this would actually be
reported as a build-time error.
Fortunately, the pattern does in fact never match, for at least two
independent reasons.
First, the code generator actually never generates a pattern of the
form (load (X86Wrapper (tglobaltlsaddr))). For most combinations of
TLS and code models, (tglobaltlsaddr) represents just an offset that
needs to be added to some base register, so it is never directly
dereferenced. The only exception is the initial-exec model, where
(tglobaltlsaddr) refers to the (pc-relative) address of a GOT slot,
which *is* in fact directly dereferenced: but in that case, the
X86WrapperRIP node is used, not X86Wrapper, so the Pat doesn't match.
Second, even if some patterns along those lines *were* ever generated,
we should not need an extra Pat pattern to match it. Instead, the
original MOV64rm instruction pattern ought to match directly, since
it uses an "addr" operand, which is implemented via the SelectAddr
C++ routine; this routine is supposed to accept the full range of
input DAGs that may be implemented by a single mov instruction,
including those cases involving ISD::TargetGlobalTLSAddress (and
actually does so e.g. in the initial-exec case as above).
To avoid build breaks (due to the above-mentioned error) after the
TableGen patch is checked in, I'm removing this Pat here.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177426 91177308-0d34-0410-b5e6-96231b3b80d8
Currently the PPC r0 register is unconditionally reserved. There are two reasons
for this:
1. r0 is treated specially (as the constant 0) by certain instructions, and so
cannot be used with those instructions as a regular register.
2. r0 is used as a temporary register in the CR-register spilling process
(where, under some circumstances, we require two GPRs).
This change addresses the first reason by introducing a restricted register
class (without r0) for use by those instructions that treat r0 specially. These
register classes have a new pseudo-register, ZERO, which represents the r0-as-0
use. This has the side benefit of making the existing target code simpler (and
easier to understand), and will make it clear to the register allocator that
uses of r0 as 0 don't conflict will real uses of the r0 register.
Once the CR spilling code is improved, we'll be able to allocate r0.
Adding these extra register classes, for some reason unclear to me, causes
requests to the target to copy 32-bit registers to 64-bit registers. The
resulting code seems correct (and causes no test-suite failures), and the new
test case covers this new kind of asymmetric copy.
As r0 is still reserved, no functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177423 91177308-0d34-0410-b5e6-96231b3b80d8
Remove an accidentally-added instruction definition and add a comment in the
test case. This is in response to a post-commit review by Bill Schmidt.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177404 91177308-0d34-0410-b5e6-96231b3b80d8
The ARM backend currently has poor codegen for long sext/zext
operations, such as v8i8 -> v8i32. This patch addresses this
by performing a custom expansion in ARMISelLowering. It also
adds/changes the cost of such lowering in ARMTTI.
This partially addresses PR14867.
Patch by Pete Couperus
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177380 91177308-0d34-0410-b5e6-96231b3b80d8
PPC64 supports unaligned loads and stores of 64-bit values, but
in order to use the r+i forms, the offset must be a multiple of 4.
Unfortunately, this cannot always be determined by examining the
immediate itself because it might be available only via a TOC entry.
In order to get around this issue, we additionally predicate the
selection of the r+i form on the alignment of the load or store
(forcing it to be at least 4 in order to select the r+i form).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177338 91177308-0d34-0410-b5e6-96231b3b80d8
The default logic marks them as too expensive.
For example, before this patch we estimated:
cost of 16 for instruction: %r = uitofp <4 x i16> %v0 to <4 x float>
While this translates to:
vmovl.u16 q8, d16
vcvt.f32.u32 q8, q8
All other costs are left to the values assigned by the fallback logic. Theses
costs are mostly reasonable in the sense that they get progressively more
expensive as the instruction sequences emitted get longer.
radar://13445992
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177334 91177308-0d34-0410-b5e6-96231b3b80d8
Fix cost of some "cheap" cast instructions. Before this patch we used to
estimate for example:
cost of 16 for instruction: %r = fptoui <4 x float> %v0 to <4 x i16>
While we would emit:
vcvt.s32.f32 q8, q8
vmovn.i32 d16, q8
vuzp.8 d16, d17
All other costs are left to the values assigned by the fallback logic. Theses
costs are mostly reasonable in the sense that they get progressively more
expensive as the instruction sequences emitted get longer.
radar://13434072
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177333 91177308-0d34-0410-b5e6-96231b3b80d8
We hitch a ride with the existing OpndItins class that was used to add
instruction itinerary classes in the many multiclasses in this file.
Use the link provided by the X86FoldableSchedWrite.Folded to find the
right SchedWrite for folded loads.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177326 91177308-0d34-0410-b5e6-96231b3b80d8
This new-style scheduling information is going to replace the
instruction iteneraries.
This also serves as a test case for Andy's fix in r177317.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177323 91177308-0d34-0410-b5e6-96231b3b80d8
This commit fixes an assert that would occur on loops with large constant counts
(like looping for ((uint32_t) -1) iterations on PPC64). The existing code did
not handle counts that it computed to be negative (asserting instead), but
these can be created with valid inputs.
This bug was discovered by bugpoint while I was attempting to isolate a
completely different problem.
Also, in writing test cases for the negative-count problem, I discovered that
the ori/lsi handling was broken (there was a typo which caused the logic that
was supposed to detect these pairs and extract the iteration count to always
fail). This has now also been corrected (and is covered by one of the new test
cases).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177295 91177308-0d34-0410-b5e6-96231b3b80d8
Because the initial-value constants had not been added to the list
of instructions considered for DCE the resulting code had redundant
constant-materialization instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177294 91177308-0d34-0410-b5e6-96231b3b80d8
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Tom Stellard <thomas.stellard@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177277 91177308-0d34-0410-b5e6-96231b3b80d8
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Tom Stellard <thomas.stellard@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177276 91177308-0d34-0410-b5e6-96231b3b80d8
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Tom Stellard <thomas.stellard@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177275 91177308-0d34-0410-b5e6-96231b3b80d8
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Tom Stellard <thomas.stellard@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177274 91177308-0d34-0410-b5e6-96231b3b80d8
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Tom Stellard <thomas.stellard@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177273 91177308-0d34-0410-b5e6-96231b3b80d8
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Tom Stellard <thomas.stellard@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177272 91177308-0d34-0410-b5e6-96231b3b80d8
Unfortunately the previous fix for inserting waits for unordered
defines wasn't sufficient, cause it's possible that even ordered
defines are only partially used (or not used at all).
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Tom Stellard <thomas.stellard@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177271 91177308-0d34-0410-b5e6-96231b3b80d8
MinGW is almost completely compatible to MSVC, with the exception of the _tls_array global not being available.
Patch by David Nadlinger!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177257 91177308-0d34-0410-b5e6-96231b3b80d8
This change cleans up two issues with Altivec register spilling:
1. The spilling code was inefficient (using two instructions, and add and a
load, when just one would do)
2. The code assumed that r0 would always be available (true for now, but this
will change)
The new code handles VR spilling just like GPR spills but forced into r+r mode.
As a result, when any VR spills are present, we must now always allocate the
register-scavenger spill slot.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177231 91177308-0d34-0410-b5e6-96231b3b80d8
As a follow-up to r158719, remove PPCRegisterInfo::avoidWriteAfterWrite.
Jakob pointed out in response to r158719 that this callback is currently unused
and so this has no effect (and the speedups that I thought that I had observed
as a result of implementing this function must have been noise).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177228 91177308-0d34-0410-b5e6-96231b3b80d8
Since almost all X86 instructions can fold loads, use a multiclass to
define register/memory pairs of SchedWrites.
An X86FoldableSchedWrite represents the register version of an
instruction. It holds a reference to the SchedWrite to use when the
instruction folds a load.
This will be used inside multiclasses that define rr and rm instruction
versions together.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177210 91177308-0d34-0410-b5e6-96231b3b80d8
I was too pessimistic in r177105. Vector selects that fit into a legal register
type lower just fine. I was mislead by the code fragment that I was using. The
stores/loads that I saw in those cases came from lowering the conditional off
an address.
Changing the code fragment to:
%T0_3 = type <8 x i18>
%T1_3 = type <8 x i1>
define void @func_blend3(%T0_3* %loadaddr, %T0_3* %loadaddr2,
%T1_3* %blend, %T0_3* %storeaddr) {
%v0 = load %T0_3* %loadaddr
%v1 = load %T0_3* %loadaddr2
==> FROM:
;%c = load %T1_3* %blend
==> TO:
%c = icmp slt %T0_3 %v0, %v1
==> USE:
%r = select %T1_3 %c, %T0_3 %v0, %T0_3 %v1
store %T0_3 %r, %T0_3* %storeaddr
ret void
}
revealed this mistake.
radar://13403975
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177170 91177308-0d34-0410-b5e6-96231b3b80d8
Unaligned access is supported on PPC for non-vector types, and is generally
more efficient than manually expanding the loads and stores.
A few of the existing test cases were using expanded unaligned loads and stores
to test other features (like load/store with update), and for these test cases,
unaligned access remains disabled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177160 91177308-0d34-0410-b5e6-96231b3b80d8
In preparation for the addition of other SIMD ISA extensions (such as QPX) we
need to make sure that all Altivec patterns are properly predicated on having
Altivec support.
No functionality change intended (one test case needed to be updated b/c it
assumed that Altivec intrinsics would be supported without enabling Altivec
support).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177152 91177308-0d34-0410-b5e6-96231b3b80d8
For spills into a large stack frame, the FI-elimination code uses the register
scavenger to obtain a free GPR for use with an r+r-addressed load or store.
When there are no available GPRs, the scavenger gets one by using its spill
slot. Previously, we were not always allocating that spill slot and the RS
would assert when the spill slot was needed.
I don't currently have a small test that triggered the assert, but I've
created a small regression test that verifies that the spill slot is now
added when the stack frame is sufficiently large.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177140 91177308-0d34-0410-b5e6-96231b3b80d8
The new InstrSchedModel is easier to use than the instruction
itineraries. It will be used to model instruction latency and throughput
in modern Intel microarchitectures like Sandy Bridge.
InstrSchedModel should be able to coexist with instruction itinerary
classes, but for cleanliness we should switch the Atom processor model
to the new InstrSchedModel as well.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177122 91177308-0d34-0410-b5e6-96231b3b80d8
See the Mips16ISetLowering.cpp patch to see a use of this.
For now now the extra code in Mips16ISetLowering.cpp is a nop but is
used for test purposes. Mips32 registers are setup and then removed and
then the Mips16 registers are setup.
Normally you need to add register classes and then call
computeRegisterProperties.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177120 91177308-0d34-0410-b5e6-96231b3b80d8
This is a generic function (derived from PEI); moving it into
MachineFrameInfo eliminates a current redundancy between the ARM and AArch64
backends, and will allow it to be used by the PowerPC target code.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177111 91177308-0d34-0410-b5e6-96231b3b80d8
Add the current PEI register scavenger as a parameter to the
processFunctionBeforeFrameFinalized callback.
This change is necessary in order to allow the PowerPC target code to
set the register scavenger frame index after the save-area offset
adjustments performed by processFunctionBeforeFrameFinalized. Only
after these adjustments have been made is it possible to estimate
the size of the stack frame.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177108 91177308-0d34-0410-b5e6-96231b3b80d8
Make requiresFrameIndexScavenging return true, and create virtual registers in
the spilling code instead of using the register scavenger directly. This makes
the target-level code simpler, and importantly, delays the scavenging until
after callee-saved register processing (which will be important for later
changes).
Also cleans up trackLivenessAfterRegAlloc (makes it inline in the header with
the other related functions). This makes it clear that it always returns true.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177107 91177308-0d34-0410-b5e6-96231b3b80d8
We used to add a spill slot for the register scavenger whenever the function
has a frame pointer. This is unnecessarily conservative: We may need the spill
slot for dynamic stack allocations, and functions with dynamic stack
allocations always have a FP, but we might also have a FP for other reasons
(such as the user explicitly disabling frame-pointer elimination), and we don't
necessarily need a spill slot for those functions.
The structsinregs test needed adjustment because it disables FP elimination.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177106 91177308-0d34-0410-b5e6-96231b3b80d8
By terrible I mean we store/load from the stack.
This matters on PAQp8 in _Z5trainPsS_ii (which is inlined into Mixer::update)
where we decide to vectorize a loop with a VF of 8 resulting in a 25%
degradation on a cortex-a8.
LV: Found an estimated cost of 2 for VF 8 For instruction: icmp slt i32
LV: Found an estimated cost of 2 for VF 8 For instruction: select i1, i32, i32
The bug that tracks the CodeGen part is PR14868.
radar://13403975
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177105 91177308-0d34-0410-b5e6-96231b3b80d8
I don't think that it is otherwise clear how the overlapping offsets
are processed into distinct spill slots. Comment that this is done
in processFunctionBeforeFrameFinalized.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177094 91177308-0d34-0410-b5e6-96231b3b80d8
This doesn't reset all of the target options within the TargetOptions
object. This is because some of those are ABI-specific and must be determined if
it's okay to change those on the fly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176986 91177308-0d34-0410-b5e6-96231b3b80d8
Increase the cost of v8/v16-i8 to v8/v16-i32 casts and truncates as the backend
currently lowers those using stack accesses.
This was responsible for a significant degradation on
MultiSource/Benchmarks/Trimaran/enc-pc1/enc-pc1
where we vectorize one loop to a vector factor of 16. After this patch we select
a vector factor of 4 which will generate reasonable code.
unsigned char cle[32];
void test(short c) {
unsigned short compte;
for (compte = 0; compte <= 31; compte++) {
cle[compte] = cle[compte] ^ c;
}
}
radar://13220512
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176898 91177308-0d34-0410-b5e6-96231b3b80d8
Now that only the register-scavenger version of the CR spilling code remains,
we no longer need the Darwin R2 hack. Darwin can use R0 as a spare register in
any case where the System V ABI uses it (R0 is special architecturally, and so
is reserved under all common ABIs).
A few test cases needed to be updated to reflect the register-allocation changes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176868 91177308-0d34-0410-b5e6-96231b3b80d8
This removes the -disable-ppc[32|64]-regscavenger options; the code
that uses the register scavenger has been working well (and has been the default)
for some time, and we don't need options to enable the old (broken) CR spilling code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176865 91177308-0d34-0410-b5e6-96231b3b80d8
