Commit Graph

30791 Commits

Author SHA1 Message Date
Chandler Carruth
8470b5b812 [x86] Flip the sentinel values used in the target shuffle mask decoding
to significantly more sane sentinels. Notably, everywhere else in the
backend's representation of shuffles uses '-1' to represent undef. The
target shuffle masks really shouldn't diverge from that, especially as
in a few places they are manipulated by shared code.

This causes us to lose some undef lanes in various test masks. I want to
get these back, but technically it isn't invalid and there are a *lot*
of bugs here so I want to try to establish a saner baseline for fixing
some of the bugs by aligning the specific senitnel values used.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218561 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-27 04:42:39 +00:00
Sanjay Patel
676af35b38 Refactor reciprocal and reciprocal square root estimate into target-independent functions (part 2).
This is purely refactoring. No functional changes intended. PowerPC is the only target
that is currently using this interface.

The ultimate goal is to allow targets other than PowerPC (certainly X86 and Aarch64) to turn this:

z = y / sqrt(x)

into:

z = y * rsqrte(x)

And:

z = y / x

into:

z = y * rcpe(x)

using whatever HW magic they can use. See http://llvm.org/bugs/show_bug.cgi?id=20900 .

There is one hook in TargetLowering to get the target-specific opcode for an estimate instruction
along with the number of refinement steps needed to make the estimate usable.

Differential Revision: http://reviews.llvm.org/D5484



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218553 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 23:01:47 +00:00
Chandler Carruth
0a31a52b91 [x86] Fix a moderately terrifying bug in the new 128-bit shuffle logic
that managed to elude all of my fuzz testing historically. =/

Something changed to allow this code path to actually be exercised and
it was doing bad things. It is especially heavily exercised by the
patterns that emerge when doing AVX shuffles that end up lowered through
the 128-bit code path.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218540 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 20:41:45 +00:00
Matt Arsenault
07b7c98d61 R600/SI: Use break instead of continue
If an instruction doesn't have src1, it doesn't have src2

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218536 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 17:55:14 +00:00
Matt Arsenault
88416c337b R600/SI: Add a note about the order of the operands to div_scale
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218534 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 17:55:09 +00:00
Matt Arsenault
508b8db287 R600/SI: Move finding SGPR operand to move to separate function
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218533 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 17:55:06 +00:00
Matt Arsenault
d991d2217b R600/SI Allow same SGPR to be used for multiple operands
Instead of moving the first SGPR that is different than the first,
legalize the operand that requires the fewest moves if one
SGPR is used for multiple operands.

This saves extra moves and is also required for some instructions
which require that the same operand be used for multiple operands.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218532 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 17:55:03 +00:00
Matt Arsenault
aed12d4bad R600/SI: Partially move operand legalization to post-isel hook.
Disable the SGPR usage restriction parts of the DAG legalizeOperands.
It now should only be doing immediate folding until it can be replaced
later. The real legalization work is now done by the other
SIInstrInfo::legalizeOperands

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218531 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 17:54:59 +00:00
Matt Arsenault
29202835d8 R600/SI: Implement findCommutedOpIndices
The base implementation of commuteInstruction is used
in some cases, but it turns out this has been broken for a
long time since modifiers were inserted between the real operands.

The base implementation of commuteInstruction also fails on immediates,
which also needs to be fixed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218530 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 17:54:54 +00:00
Matt Arsenault
8a70e28114 R600/SI: Don't move operands that are required to be SGPRs
e.g. v_cndmask_b32 requires the condition operand be an SGPR.
If one of the source operands were an SGPR, that would be considered
the one SGPR use and the condition operand would be illegally moved.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218529 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 17:54:52 +00:00
Matt Arsenault
5b199b585c R600/SI: Don't assert on exotic operand types
This needs a test, but I'm not sure if it is currently possible and
I originally hit it due to a bug. Right now the only global address
operands have no reason to be VALU instructions, although it
theoretically could be a problem.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218528 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 17:54:46 +00:00
Matt Arsenault
26b2a7834e R600/SI: Fix using wrong operand indices when commuting
No test since the current SIISelLowering::legalizeOperands
effectively hides this, and the general uses seem to only fire
on SALU instructions which don't have modifiers between
the operands.

When trying to use legalizeOperands immediately after
instruction selection, it now sees a lot more patterns
it did not see before which break on this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218527 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 17:54:43 +00:00
Matt Arsenault
ea849e9adc R600/SI: Remove apparently dead code in legalizeOperands
No tests hit this, and I don't see any way a GlobalAddress
node would survive beyond lowering on SI. It it would, the
move should probably be inserted by selection.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218526 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 17:54:38 +00:00
Chandler Carruth
a7579ed23f [x86] The mnemonic is SHUFPS not SHUPFS. =[ I'm very bad at spelling
sadly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218524 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 17:27:40 +00:00
Chandler Carruth
7929a210d5 [x86] In the new vector shuffle lowering, when trying to do another
layer of tie-breaking sorting, it really helps to check that you're in
a tie first. =] Otherwise the whole thing cycles infinitely. Test case
added, another one found through fuzz testing.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218523 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 17:24:26 +00:00
Chandler Carruth
7164a4ae0a [x86] Fix a large collection of bugs that crept in as I fleshed out the
AVX support.

New test cases included. Note that none of the existing test cases
covered these buggy code paths. =/ Also, it is clear from this that
SHUFPS and SHUFPD are the most bug prone shuffle instructions in x86. =[

These were all detected by fuzz-testing. (I <3 fuzz testing.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218522 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 17:11:02 +00:00
Renato Golin
6215f78195 Elide repeated register operand in Thumb1 instructions
This patch makes the ARM backend transform 3 operand instructions such as
'adds/subs' to the 2 operand version of the same instruction if the first
two register operands are the same.

Example: 'adds r0, r0, #1' will is transformed to 'adds r0, #1'.

Currently for some instructions such as 'adds' if you try to assemble
'adds r0, r0, #8' for thumb v6m the assembler would throw an error message
because the immediate cannot be encoded using 3 bits.

The backend should be smart enough to transform the instruction to
'adds r0, #8', which allows for larger immediate constants.

Patch by Ranjeet Singh.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218521 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 16:14:29 +00:00
Andrea Di Biagio
a5ab9baf83 [X86][SchedModel] SSE reciprocal square root instruction latencies.
The SSE rsqrt instruction (a fast reciprocal square root estimate) was
grouped in the same scheduling IIC_SSE_SQRT* class as the accurate (but very
slow) SSE sqrt instruction. For code which uses rsqrt (possibly with
newton-raphson iterations) this poor scheduling was affecting performances.

This patch splits off the rsqrt instruction from the sqrt instruction scheduling
classes and creates new IIC_SSE_RSQER* classes with latency values based on
Agner's table.

Differential Revision: http://reviews.llvm.org/D5370

Patch by Simon Pilgrim.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218517 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 12:56:44 +00:00
Daniel Sanders
12aa552637 Fix unused variable warning added in r218509
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218510 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 10:45:26 +00:00
Daniel Sanders
7ecd98679e [mips] Generalize the handling of f128 return values to support f128 arguments.
Summary:
This will allow us to handle f128 arguments without duplicating code from
CCState::AnalyzeFormalArguments() or CCState::AnalyzeCallOperands().

No functional change.

Reviewers: vmedic

Reviewed By: vmedic

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5292

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218509 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 10:06:12 +00:00
Robert Khasanov
26ba182fdf [AVX512] Added load/store from BW/VL subsets to Register2Memory opcode tables.
Added lowering tests for these instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218508 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 09:48:50 +00:00
David Majnemer
ed2b7578b8 Fix build breakage on MSVC 2013
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218499 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 04:47:54 +00:00
David Majnemer
af100b0350 Target: Fix build breakage.
No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218497 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 02:57:05 +00:00
Eric Christopher
55a90ab4ef Add the first backend support for on demand subtarget creation
based on the Function. This is currently used to implement
mips16 support in the mips backend via the existing module
pass resetting the subtarget.

Things to note:

a) This involved running resetTargetOptions before creating a
new subtarget so that code generation options like soft-float
could be recognized when creating the new subtarget. This is
to deal with initialization code in isel lowering that only
paid attention to the initial value.

b) Many of the existing testcases weren't using the soft-float
feature correctly. I've corrected these based on the check
values assuming that was the desired behavior.

c) The mips port now pays attention to the target-cpu and
target-features strings when generating code for a particular
function. I've removed these from one function where the
requested cpu and features didn't match the check lines in
the testcase.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218492 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 01:44:08 +00:00
Eric Christopher
a6e0a6e729 Move resetTargetOptions from taking a MachineFunction to a Function
since we are accessing the TargetMachine that we're a member
function of.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218489 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 01:28:10 +00:00
Matt Arsenault
584886c0bb R600/SI: Fix emitting trailing whitespace after s_waitcnt
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218486 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 01:09:46 +00:00
Adam Nemet
479f2f7a14 [AVX512] Simplify use of !con()
No change in X86.td.expanded.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218485 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 00:53:12 +00:00
Adam Nemet
08f261afbf [AVX512] Pull pattern for subvector extract into the instruction definition
No functional change.

I initially thought that pulling the Pat<> into the instruction pattern was
not possible because it was doing a transform on the index in order to convert
it from a per-element (extract_subvector) index into a per-chunk (vextract*x4)
index.

Turns out this also works inside the pattern because the vextract_extract
PatFrag has an OperandTransform EXTRACT_get_vextract{128,256}_imm, so the
index in $idx goes through the same conversion.

The existing test CodeGen/X86/avx512-insert-extract.ll extended in the
previous commit provides coverage for this change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218480 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 23:48:49 +00:00
Adam Nemet
4007b30ede [AVX512] Refactor subvector extracts
No functional change.

These are now implemented as two levels of multiclasses heavily relying on the
new X86VectorVTInfo class.  The multiclass at the first level that is called
with float or int provides the 128 or 256 bit subvector extracts.  The second
level provides the register and memory variants and some more Pat<>s.

I've compared the td.expanded files before and after.  One change is that
ExeDomain for 64x4 is SSEPackedDouble now.  I think this is correct, i.e. a
bugfix.

(BTW, this is the change that was blocked on the recent tablegen fix.  The
class-instance values X86VectorVTInfo inside vextract_for_type weren't
properly evaluated.)

Part of <rdar://problem/17688758>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218478 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 23:48:45 +00:00
Adam Nemet
1973ffefcf [AVX512] Fix typo
F->I in VEXTRACTF32x4rr.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218477 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 23:48:42 +00:00
Tom Stellard
8361c84894 ARM: Remove unneeded check for MI->hasPostISelHook()
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218459 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 18:59:23 +00:00
Tom Stellard
29d48e6a49 R600/SI: Add support for global atomic add
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218457 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 18:30:26 +00:00
Robin Morisset
79826e015e Lower idempotent RMWs to fence+load
Summary:
I originally tried doing this specifically for X86 in the backend in D5091,
but it was rather brittle and generally running too late to be general.
Furthermore, other targets may want to implement similar optimizations.
So I reimplemented it at the IR-level, fitting it into AtomicExpandPass
as it interacts with that pass (which could not be cleanly done before
at the backend level).

This optimization relies on a new target hook, which is only used by X86
for now, as the correctness of the optimization on other targets remains
an open question. If it is found correct on other targets, it should be
trivial to enable for them.

Details of the optimization are discussed in D5091.

Test Plan: make check-all + a new test

Reviewers: jfb

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5422

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218455 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 17:27:43 +00:00
Sid Manning
733681d3bd Add missing attributes !cmp.[eq,gt,gtu] instructions.
These instructions do not indicate they are extendable or the
number of bits in the extendable operand.  Rename to match
architected names.  Add a testcase for the intrinsics.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218453 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 13:09:54 +00:00
Daniel Sanders
1d545d9acb Add llvm_unreachables() for [ASZ]ExtUpper to X86FastISel.cpp to appease the buildbots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218452 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 13:08:51 +00:00
Daniel Sanders
03fe69e90d [mips] Add CCValAssign::[ASZ]ExtUpper and CCPromoteToUpperBitsInType and handle struct's correctly on big-endian N32/N64 return values.
Summary:
The N32/N64 ABI's require that structs passed in registers are laid out
such that spilling the register with 'sd' places the struct at the lowest
address. For little endian this is trivial but for big-endian it requires
that structs are shifted into the upper bits of the register.

We also require that structs passed in registers have the 'inreg'
attribute for big-endian N32/N64 to work correctly. This is because the
tablegen-erated calling convention implementation only has access to the
lowered form of struct arguments (one or more integers of up to 64-bits
each) and is unable to determine the original type.

Reviewers: vmedic

Reviewed By: vmedic

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5286

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218451 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 12:15:05 +00:00
Renato Golin
6765c34b0c Add aliases for VAND imm to VBIC ~imm
On ARM NEON, VAND with immediate (16/32 bits) is an alias to VBIC ~imm with
the same type size. Adding that logic to the parser, and generating VBIC
instructions from VAND asm files.

This patch also fixes the validation routines for NEON splat immediates which
were wrong.

Fixes PR20702.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218450 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 11:31:24 +00:00
Chandler Carruth
4b667ee436 [x86] Teach the new vector shuffle lowering to use AVX2 instructions for
v4f64 and v8f32 shuffles when they are lane-crossing. We have fully
general lane-crossing permutation functions in AVX2 that make this easy.

Part of this also changes exactly when and how these vectors are split
up when we don't have AVX2. This isn't always a win but it usually is
a win, so on the balance I think its better. The primary regressions are
all things that just need to be fixed anyways such as modeling when
a blend can be completely accomplished via VINSERTF128, etc.

Also, this highlights one of the few remaining big features: we do
a really poor job of inserting elements into AVX registers efficiently.

This completes almost all of the big tricks I have in mind for AVX2. The
only things left that I plan to add:

1) element insertion smarts
2) palignr and other fairly specialized lowerings when they happen to
   apply

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218449 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 11:03:55 +00:00
Chandler Carruth
05901d80ba [x86] Teach the new vector shuffle lowering a fancier way to lower
256-bit vectors with lane-crossing.

Rather than immediately decomposing to 128-bit vectors, try flipping the
256-bit vector lanes, shuffling them and blending them together. This
reduces our worst case shuffle by a pretty significant margin across the
board.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218446 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 10:21:15 +00:00
Oliver Stannard
f220c5387b [Thumb2] BXJ should be undefined for v7M, v8A
The Thumb2 BXJ instruction (Branch and Exchange Jazelle) is not
defined for v7M or v8A. It is defined for all other Thumb2-supporting
architectures (v6T2, v7A and v7R).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218445 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 10:02:05 +00:00
Chandler Carruth
2e8d2c727c [x86] Fix an oversight in the v8i32 path of the new vector shuffle
lowering where it only used the mask of the low 128-bit lane rather than
the entire mask.

This allows the new lowering to correctly match the unpack patterns for
v8i32 vectors.

For reference, the reason that we check for the the entire mask rather
than checking the repeated mask is because the repeated masks don't
abide by all of the invariants of normal masks. As a consequence, it is
safer to use the full mask with functions like the generic equivalence
test.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218442 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 04:10:27 +00:00
Chandler Carruth
e5fb4ad142 [x86] Rearrange the code for v16i16 lowering a bit for clarity and to
reduce the amount of checking we do here.

The first realization is that only non-crossing cases between 128-bit
lanes are handled by almost the entire function. It makes more sense to
handle the crossing cases first.

THe second is that until we actually are going to generate fancy shared
lowering strategies that use the repeated semantics of the v8i16
lowering, we should waste time checking for repeated masks. It is
simplest to directly test for the entire unpck masks anyways, so we
gained nothing from this.

This also matches the structure of v32i8 more closely.

No functionality changed here.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218441 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 04:03:22 +00:00
Chandler Carruth
e3bb4bb2d5 [x86] Implement AVX2 support for v32i8 in the new vector shuffle
lowering.

This completes the basic AVX2 feature support, but there are still some
improvements I'd like to do to really get the last mile of performance
here.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218440 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 02:52:12 +00:00
Chandler Carruth
6a289bb491 [x86] Remove the defunct X86ISD::BLENDV entry -- we use vector selects
for this now.

Should prevent folks from running afoul of this and not knowing why
their code won't instruction select the way I just did...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218436 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 01:16:01 +00:00
Chandler Carruth
ef673b3c73 [x86] Fix the v16i16 blend logic I added in the prior commit and add the
missing test cases for it.

Unsurprisingly, without test cases, there were bugs here. Surprisingly,
this bug wasn't caught at compile time. Yep, there is an X86ISD::BLENDV.
It isn't wired to anything. Oops. I'll fix than next.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218434 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 01:13:38 +00:00
Akira Hatanaka
0253523c92 [X86,AVX] Add an isel pattern for X86VBroadcast.
This fixes PR21050 and rdar://problem/18434607.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218431 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 00:26:15 +00:00
Chandler Carruth
bdecfeb723 [x86] Implement v16i16 support with AVX2 in the new vector shuffle
lowering.

This also implements the fancy blend lowering for v16i16 using AVX2 and
teaches the X86 backend to print shuffle masks for 256-bit PSHUFB
and PBLENDW instructions. It also makes the mask decoding correct for
PBLENDW instructions. The yaks, they are legion.

Tests are updated accordingly. There are some missing tests for the
VBLENDVB lowering, but I'll add those in a follow-up as this commit has
accumulated enough cruft already.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218430 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 00:24:19 +00:00
Chandler Carruth
c88ae9687b [x86] Factor out the logic to generically decombose a vector shuffle
into unblended shuffles and a blend.

This is the consistent fallback for the lowering paths that have fast
blend operations available, and its getting quite repetitive.

No functionality changed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218399 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-24 18:20:09 +00:00
Moritz Roth
8c4e64af8a [Thumb] Make load/store optimizer less conservative.
If it's safe to clobber the condition flags, we can do a few extra things:
it's then possible to reset the base register writeback using a SUBS, so
we can try to merge even if the base register isn't dead after the merged
instruction.

This is effectively a (heavily bug-fixed) rewrite of r208992.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218386 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-24 16:35:50 +00:00
Oliver Stannard
43c6b6be8f [Thumb] 32-bit encodings of 'cps' are not valid for v7M
v7M only allows the 16-bit encoding of the 'cps' (Change Processor
State) instruction, and does not have the 32-bit encoding which is
valid from v6T2 onwards.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218382 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-24 14:20:01 +00:00