Commit Graph

561 Commits

Author SHA1 Message Date
James Molloy e7d97368f2 Revert "[Thumb] Teach ISel how to lower compares of AND bitmasks efficiently"
This reverts commit r285893. It caused (probably) http://lab.llvm.org:8011/builders/clang-cmake-thumbv7-a15-full-sh/builds/83 .

llvm-svn: 285912
2016-11-03 14:08:01 +00:00
James Molloy b60d8b1987 [Thumb] Teach ISel how to lower compares of AND bitmasks efficiently
This recommits r281323, which was backed out for two reasons. One, a selfhost failure, and two, it apparently caused Chromium failures. Actually, the latter was a red herring. The log has expired from the former, but I suspect that was a red herring too (actually caused by another problematic patch of mine). Therefore reapplying, and will watch the bots like a hawk.

For the common pattern (CMPZ (AND x, #bitmask), #0), we can do some more efficient instruction selection if the bitmask is one consecutive sequence of set bits (32 - clz(bm) - ctz(bm) == popcount(bm)).

1) If the bitmask touches the LSB, then we can remove all the upper bits and set the flags by doing one LSLS.
2) If the bitmask touches the MSB, then we can remove all the lower bits and set the flags with one LSRS.
3) If the bitmask has popcount == 1 (only one set bit), we can shift that bit into the sign bit with one LSLS and change the condition query from NE/EQ to MI/PL (we could also implement this by shifting into the carry bit and branching on BCC/BCS).
4) Otherwise, we can emit a sequence of LSLS+LSRS to remove the upper and lower zero bits of the mask.

1-3 require only one 16-bit instruction and can elide the CMP. 4 requires two 16-bit instructions but can elide the CMP and doesn't require materializing a complex immediate, so is also a win.

llvm-svn: 285893
2016-11-03 10:18:20 +00:00
Tim Northover a9cc385664 ARM: don't rely on push/pop reglists being in order when folding SP adjust.
It would be a very nice invariant to rely on, but unfortunately it doesn't
necessarily hold (and the causes of mis-sorted reglists appear to be quite
varied) so to be robust the frame lowering code can't assume that the first
register in the list is also the first one that actually gets pushed.

Should fix an issue where we were turning something like:

    push {r8, r4, r7, lr}
    sub sp, #24

into nonsense like:

    push {r2, r3, r4, r5, r6, r7, r8, r4, r7, lr}

llvm-svn: 285232
2016-10-26 20:01:00 +00:00
Matt Arsenault 1b9fc8ed65 Finish renaming remaining analyzeBranch functions
llvm-svn: 281535
2016-09-14 20:43:16 +00:00
Matt Arsenault e8e0f5cac6 Make analyzeBranch family of instruction names consistent
analyzeBranch was renamed to use lowercase first, rename
the related set to match.

llvm-svn: 281506
2016-09-14 17:24:15 +00:00
Matt Arsenault a2b036e88b AArch64: Use TTI branch functions in branch relaxation
The main change is to return the code size from
InsertBranch/RemoveBranch.

Patch mostly by Tim Northover

llvm-svn: 281505
2016-09-14 17:23:48 +00:00
James Molloy 9790d8f81d Revert "[Thumb] Teach ISel how to lower compares of AND bitmasks efficiently"
This reverts commit r281323. It caused chromium test failures and a selfhost failure.

llvm-svn: 281451
2016-09-14 09:45:28 +00:00
James Molloy d246c598de [Thumb] Teach ISel how to lower compares of AND bitmasks efficiently
For the common pattern (CMPZ (AND x, #bitmask), #0), we can do some more efficient instruction selection if the bitmask is one consecutive sequence of set bits (32 - clz(bm) - ctz(bm) == popcount(bm)).

1) If the bitmask touches the LSB, then we can remove all the upper bits and set the flags by doing one LSLS.
2) If the bitmask touches the MSB, then we can remove all the lower bits and set the flags with one LSRS.
3) If the bitmask has popcount == 1 (only one set bit), we can shift that bit into the sign bit with one LSLS and change the condition query from NE/EQ to MI/PL (we could also implement this by shifting into the carry bit and branching on BCC/BCS).
4) Otherwise, we can emit a sequence of LSLS+LSRS to remove the upper and lower zero bits of the mask.

1-3 require only one 16-bit instruction and can elide the CMP. 4 requires two 16-bit instructions but can elide the CMP and doesn't require materializing a complex immediate, so is also a win.

llvm-svn: 281323
2016-09-13 12:12:32 +00:00
Nico Weber 7c31d0ebc0 Revert r281215, it caused PR30358.
llvm-svn: 281263
2016-09-12 21:40:50 +00:00
James Molloy 1e1b56bd48 [Thumb] Teach ISel how to lower compares of AND bitmasks efficiently
For the common pattern (CMPZ (AND x, #bitmask), #0), we can do some more efficient instruction selection if the bitmask is one consecutive sequence of set bits (32 - clz(bm) - ctz(bm) == popcount(bm)).

1) If the bitmask touches the LSB, then we can remove all the upper bits and set the flags by doing one LSLS.
2) If the bitmask touches the MSB, then we can remove all the lower bits and set the flags with one LSRS.
3) If the bitmask has popcount == 1 (only one set bit), we can shift that bit into the sign bit with one LSLS and change the condition query from NE/EQ to MI/PL (we could also implement this by shifting into the carry bit and branching on BCC/BCS).
4) Otherwise, we can emit a sequence of LSLS+LSRS to remove the upper and lower zero bits of the mask.

1-3 require only one 16-bit instruction and can elide the CMP. 4 requires two 16-bit instructions but can elide the CMP and doesn't require materializing a complex immediate, so is also a win.

llvm-svn: 281215
2016-09-12 14:30:48 +00:00
Justin Lebar adbf09e8cf [CodeGen] Split out the notions of MI invariance and MI dereferenceability.
Summary:
An IR load can be invariant, dereferenceable, neither, or both.  But
currently, MI's notion of invariance is IR-invariant &&
IR-dereferenceable.

This patch splits up the notions of invariance and dereferenceability at
the MI level.  It's NFC, so adds some probably-unnecessary
"is-dereferenceable" checks, which we can remove later if desired.

Reviewers: chandlerc, tstellarAMD

Subscribers: jholewinski, arsenm, nemanjai, llvm-commits

Differential Revision: https://reviews.llvm.org/D23371

llvm-svn: 281151
2016-09-11 01:38:58 +00:00
James Molloy 0f41227b21 [Thumb1] Teach optimizeCompareInstr about thumb1 compares
This avoids us doing a completely unneeded "cmp r0, #0" after a flag-setting instruction if we only care about the Z or C flags.

Add LSL/LSR to the whitelist while we're here and add testing. This code could really do with a spring clean.

llvm-svn: 281027
2016-09-09 09:51:06 +00:00
Saleem Abdulrasool bfa25bd1ac ARM: workaround bundled operation predication
This is a Windows ARM specific issue.  If the code path in the if conversion
ends up using a relocation which will form a IMAGE_REL_ARM_MOV32T, we end up
with a bundle to ensure that the mov.w/mov.t pair is not split up.  This is
normally fine, however, if the branch is also predicated, then we end up trying
to predicate the bundle.

For now, report a bundle as being unpredicatable.  Although this is false, this
would trigger a failure case previously anyways, so this is no worse.  That is,
there should not be any code which would previously have been if converted and
predicated which would not be now.

Under certain circumstances, it may be possible to "predicate the bundle".  This
would require scanning all bundle instructions, and ensure that the bundle
contains only predicatable instructions, and converting the bundle into an IT
block sequence.  If the bundle is larger than the maximal IT block length (4
instructions), it would require materializing multiple IT blocks from the single
bundle.

llvm-svn: 280689
2016-09-06 04:00:12 +00:00
Oliver Stannard 8331aaee8f [ARM] Add support for embedded position-independent code
This patch adds support for some new relocation models to the ARM
backend:

* Read-only position independence (ROPI): Code and read-only data is accessed
  PC-relative. The offsets between all code and RO data sections are known at
  static link time. This does not affect read-write data.
* Read-write position independence (RWPI): Read-write data is accessed relative
  to the static base register (r9). The offsets between all writeable data
  sections are known at static link time. This does not affect read-only data.

These two modes are independent (they specify how different objects
should be addressed), so they can be used individually or together. They
are otherwise the same as the "static" relocation model, and are not
compatible with SysV-style PIC using a global offset table.

These modes are normally used by bare-metal systems or systems with
small real-time operating systems. They are designed to avoid the need
for a dynamic linker, the only initialisation required is setting r9 to
an appropriate value for RWPI code.

I have only added support to SelectionDAG, not FastISel, because
FastISel is currently disabled for bare-metal targets where these modes
would be used.

Differential Revision: https://reviews.llvm.org/D23195

llvm-svn: 278015
2016-08-08 15:28:31 +00:00
Matthias Braun 941a705b7b MachineFunction: Return reference for getFrameInfo(); NFC
getFrameInfo() never returns nullptr so we should use a reference
instead of a pointer.

llvm-svn: 277017
2016-07-28 18:40:00 +00:00
Sjoerd Meijer 89217f8835 TargetInstrInfo: rename GetInstSizeInBytes to getInstSizeInBytes. NFC
Differential Revision: https://reviews.llvm.org/D22925

llvm-svn: 276997
2016-07-28 16:32:22 +00:00
Justin Lebar 0af80cd6f0 [CodeGen] Take a MachineMemOperand::Flags in MachineFunction::getMachineMemOperand.
Summary:
Previously we took an unsigned.

Hooray for type-safety.

Reviewers: chandlerc

Subscribers: dsanders, llvm-commits

Differential Revision: http://reviews.llvm.org/D22282

llvm-svn: 275591
2016-07-15 18:26:59 +00:00
Jacques Pienaar 71c30a14b7 Rename AnalyzeBranch* to analyzeBranch*.
Summary: NFC. Rename AnalyzeBranch/AnalyzeBranchPredicate to analyzeBranch/analyzeBranchPredicate to follow LLVM coding style and be consistent with TargetInstrInfo's analyzeCompare and analyzeSelect.

Reviewers: tstellarAMD, mcrosier

Subscribers: mcrosier, jholewinski, jfb, arsenm, dschuff, jyknight, dsanders, nemanjai

Differential Revision: https://reviews.llvm.org/D22409

llvm-svn: 275564
2016-07-15 14:41:04 +00:00
Duncan P. N. Exon Smith 29c524983b ARM: Remove implicit iterator conversions, NFC
Remove remaining implicit conversions from MachineInstrBundleIterator to
MachineInstr* from the ARM backend.  In most cases, I made them less attractive
by preferring MachineInstr& or using a ranged-based for loop.

Once all the backends are fixed I'll make the operator explicit so that this
doesn't bitrot back.

llvm-svn: 274920
2016-07-08 20:21:17 +00:00
Saleem Abdulrasool eb059b0e0a ARM: support high registers in __builtin_longjmp on WoA
Windows on ARM uses a pure thumb-2 environment.  This means that it can select a
high register when doing a __builtin_longjmp.  We would use a tLDRi which would
truncate the register to a low register.  Use a t2LDRi12 to get the full
register file access.  Tweak the code to just load into PC, as that is an
interworking branch on all supported cores anyways.

llvm-svn: 274815
2016-07-08 00:48:22 +00:00
Diana Picus b772e409ba [ARM] Do not test for CPUs, use SubtargetFeatures. Also remove 2 flags.
This is a follow-up for r273544.

The end goal is to get rid of the isSwift / isCortexXY / isWhatever methods.

This commit also removes two command-line flags that weren't used in any of the
tests: widen-vmovs and swift-partial-update-clearance. The former may be easily
replaced with the mattr mechanism, but the latter may not (as it is a subtarget
property, and not a proper feature).

Differential Revision: http://reviews.llvm.org/D21797

llvm-svn: 274620
2016-07-06 11:22:11 +00:00
Duncan P. N. Exon Smith d26fdc83c9 CodeGen: Use MachineInstr& in LiveVariables API, NFC
Change all the methods in LiveVariables that expect non-null
MachineInstr* to take MachineInstr& and update the call sites.  This
clarifies the API, and designs away a class of iterator to pointer
implicit conversions.

llvm-svn: 274319
2016-07-01 01:51:32 +00:00
Duncan P. N. Exon Smith 9cfc75c214 CodeGen: Use MachineInstr& in TargetInstrInfo, NFC
This is mostly a mechanical change to make TargetInstrInfo API take
MachineInstr& (instead of MachineInstr* or MachineBasicBlock::iterator)
when the argument is expected to be a valid MachineInstr.  This is a
general API improvement.

Although it would be possible to do this one function at a time, that
would demand a quadratic amount of churn since many of these functions
call each other.  Instead I've done everything as a block and just
updated what was necessary.

This is mostly mechanical fixes: adding and removing `*` and `&`
operators.  The only non-mechanical change is to split
ARMBaseInstrInfo::getOperandLatencyImpl out from
ARMBaseInstrInfo::getOperandLatency.  Previously, the latter took a
`MachineInstr*` which it updated to the instruction bundle leader; now,
the latter calls the former either with the same `MachineInstr&` or the
bundle leader.

As a side effect, this removes a bunch of MachineInstr* to
MachineBasicBlock::iterator implicit conversions, a necessary step
toward fixing PR26753.

Note: I updated WebAssembly, Lanai, and AVR (despite being
off-by-default) since it turned out to be easy.  I couldn't run tests
for AVR since llc doesn't link with it turned on.

llvm-svn: 274189
2016-06-30 00:01:54 +00:00
Rafael Espindola 5ac8f5c379 Don't pass a Reloc::Model to GVIsIndirectSymbol.
It already has access to it.

While at it, rename it to isGVIndirectSymbol.

llvm-svn: 274023
2016-06-28 15:38:13 +00:00
Rafael Espindola 82f4631c88 Don't pass Reloc::Model to places that already have it. NFC.
llvm-svn: 274022
2016-06-28 15:18:26 +00:00
Diana Picus 92423ce194 [ARM] Do not test for CPUs, use SubtargetFeatures (Part 2). NFCI
This is a follow-up for r273544.

The end goal is to get rid of the isSwift / isCortexXY / isWhatever methods.

Since the ARM backend seems to have quite a lot of calls to these methods, I
intend to submit 5-6 subtarget features at a time, instead of one big lump.

Differential Revision: http://reviews.llvm.org/D21685

llvm-svn: 273853
2016-06-27 09:08:23 +00:00
Diana Picus c5baa43f53 [ARM] Do not test for CPUs, use SubtargetFeatures (Part 1). NFCI
This is a cleanup commit similar to r271555, but for ARM.

The end goal is to get rid of the isSwift / isCortexXY / isWhatever methods.

Since the ARM backend seems to have quite a lot of calls to these methods, I
intend to submit 5-6 subtarget features at a time, instead of one big lump.

Differential Revision: http://reviews.llvm.org/D21432

llvm-svn: 273544
2016-06-23 07:47:35 +00:00
Benjamin Kramer bdc4956bac Pass DebugLoc and SDLoc by const ref.
This used to be free, copying and moving DebugLocs became expensive
after the metadata rewrite. Passing by reference eliminates a ton of
track/untrack operations. No functionality change intended.

llvm-svn: 272512
2016-06-12 15:39:02 +00:00
Diana Picus 0781d10ac4 [ARM] Remove redundant check. NFC
isSwift is tested earlier and known to be false when we reach this code.

llvm-svn: 272127
2016-06-08 10:29:02 +00:00
Tim Northover c08db1840c ARM: fix handling of SUB immediates in peephole opt.
We were negating an immediate that was going to be used in a SUBri form
unnecessarily. Since ADD/SUB are very similar we *can* do that, but we have to
change the SUB to an ADD at the same time. This also applies to ADD, and allows
us to handle a slightly larger range of immediates for those two operations.

rdar://25992245

llvm-svn: 268276
2016-05-02 18:30:08 +00:00
Saleem Abdulrasool 1632fe1f77 ARM: follow up improvements for SVN r263118
The initial change was insufficiently complete for always getting the semantics
of __builtin_longjmp correct.  The builtin is translated into a
`tInt_eh_sjlj_longjmp` DAG node.  This node set R7 as clobbered.  However, the
code would then follow up with a clobber of R11.  I had failed to notice the
imp-def,kill on R7 in the isel.  Unfortunately, it seems that it is not possible
to conditionalise the Defs list via an !if.  Instead, construct a new parallel
WIN node and prefer that when targeting windows.  This ensures that we now both
correctly model the __builtin_longjmp as well as construct the frame in a more
ABI conformant manner.

llvm-svn: 263123
2016-03-10 16:26:37 +00:00
Duncan P. N. Exon Smith fd8cc23220 CodeGen: Change MachineInstr to use MachineInstr&, NFC
Change MachineInstr API to prefer MachineInstr& over MachineInstr*
whenever the parameter is expected to be non-null.  Slowly inching
toward being able to fix PR26753.

llvm-svn: 262149
2016-02-27 20:01:33 +00:00
Duncan P. N. Exon Smith 6307eb5518 CodeGen: TII: Take MachineInstr& in predicate API, NFC
Change TargetInstrInfo API to take `MachineInstr&` instead of
`MachineInstr*` in the functions related to predicated instructions
(I'll try to come back later and get some of the rest).  All of these
functions require non-null parameters already, so references are more
clear.  As a bonus, this happens to factor away a host of implicit
iterator => pointer conversions.

No functionality change intended.

llvm-svn: 261605
2016-02-23 02:46:52 +00:00
Duncan P. N. Exon Smith d84f600653 CodeGen: Bring back MachineBasicBlock::iterator::getInstrIterator()...
This is a little embarrassing.

When I reverted r261504 (getIterator() => getInstrIterator()) in
r261567, I did a `git grep` to see if there were new calls to
`getInstrIterator()` that I needed to migrate.  There were 10-20 hits,
and I blindly did a `sed ...` before calling `ninja check`.

However, these were `MachineInstrBundleIterator::getInstrIterator()`,
which predated r261567.  Perhaps coincidentally, these had an identical
name and return type.

This commit undoes my careless sed and restores
`MachineBasicBlock::iterator::getInstrIterator()`.

llvm-svn: 261577
2016-02-22 21:30:15 +00:00
Duncan P. N. Exon Smith c5b668deb8 Revert "CodeGen: MachineInstr::getIterator() => getInstrIterator(), NFC"
This reverts commit r261504, since it's not obvious the new name is
better:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20160222/334298.html

I'll recommit if we get consensus that it's the right direction.

llvm-svn: 261567
2016-02-22 20:49:58 +00:00
Duncan P. N. Exon Smith dc0848c029 CodeGen: MachineInstr::getIterator() => getInstrIterator(), NFC
Delete MachineInstr::getIterator(), since the term "iterator" is
overloaded when talking about MachineInstr.

- Downcast to ilist_node in iplist::getNextNode() and getPrevNode() so
  that ilist_node::getIterator() is still available.
- Add it back as MachineInstr::getInstrIterator().  This matches the
  naming in MachineBasicBlock.
- Add MachineInstr::getBundleIterator().  This is explicitly called
  "bundle" (not matching MachineBasicBlock) to disintinguish it clearly
  from ilist_node::getIterator().
- Update all calls.  Some of these I switched to `auto` to remove
  boiler-plate, since the new name is clear about the type.

There was one call I updated that looked fishy, but it wasn't clear what
the right answer was.  This was in X86FrameLowering::inlineStackProbe(),
added in r252578 in lib/Target/X86/X86FrameLowering.cpp.  I opted to
leave the behaviour unchanged, but I'll reply to the original commit on
the list in a moment.

llvm-svn: 261504
2016-02-21 22:58:35 +00:00
Matthias Braun 60d69e2865 CodeGen: Redo analyzePhysRegs() and computeRegisterLiveness()
computeRegisterLiveness() was broken in that it reported dead for a
register even if a subregister was alive. I assume this was because the
results of analayzePhysRegs() are hard to understand with respect to
subregisters.

This commit: Changes the results of analyzePhysRegs (=struct
PhysRegInfo) to be clearly understandable, also renames the fields to
avoid silent breakage of third-party code (and improve the grammar).

Fix all (two) users of computeRegisterLiveness() in llvm: By reenabling
it and removing workarounds for the bug.

This fixes http://llvm.org/PR24535 and http://llvm.org/PR25033

Differential Revision: http://reviews.llvm.org/D15320

llvm-svn: 255362
2015-12-11 19:42:09 +00:00
Peter Collingbourne 97aae40880 ARM/ELF: Better codegen for global variable addresses.
In PIC mode we were previously computing global variable addresses (or GOT
entry addresses) by adding the PC, the PC-relative GOT displacement and
the GOT-relative symbol/GOT entry displacement. Because the latter two
displacements are fixed, we ended up performing one more addition than
necessary.

This change causes us to compute addresses using a single PC-relative
displacement, resulting in a shorter code sequence. This reduces code size
by about 4% in a recent build of Chromium for Android.

As a result of this change we no longer need to compute the GOT base address
in the ARM backend, which allows us to remove the Global Base Reg pass and
SDAG lowering for the GOT.

We also now no longer use the GOT when addressing a symbol which is known
to be defined in the same linkage unit. Specifically, the symbol must have
either hidden visibility or a strong definition in the current module in
order to not use the the GOT.

This is a change from the previous behaviour where we would use the GOT to
address externally visible symbols defined in the same module. I think the
only cases where this could matter are cases involving symbol interposition,
but we don't really support that well anyway.

Differential Revision: http://reviews.llvm.org/D13650

llvm-svn: 251322
2015-10-26 18:23:16 +00:00
Benjamin Kramer 8ceb323bb4 Convert assert(false) into llvm_unreachable where it makes sense.
llvm-svn: 251266
2015-10-25 22:28:27 +00:00
Duncan P. N. Exon Smith 9f9559e807 ARM: Remove implicit ilist iterator conversions, NFC
llvm-svn: 250759
2015-10-19 23:25:57 +00:00
Scott Douglass 953f908173 [ARM] Modify codegen for memcpy intrinsic to prefer LDM/STM.
We were previously codegen'ing memcpy as regular load/store operations and
hoping that the register allocator would allocate registers in ascending order
so that we could apply an LDM/STM combine after register allocation. According
to the commit that first introduced this code (r37179), we planned to teach the
register allocator to allocate the registers in ascending order. This never got
implemented, and up to now we've been stuck with very poor codegen.

A much simpler approach for achieving better codegen is to create MEMCPY pseudo
instructions, attach scratch virtual registers to them and then, post register
allocation, expand the MEMCPYs into LDM/STM pairs using the scratch registers.
The register allocator will have picked arbitrary registers which we sort when
expanding the MEMCPY. This approach also avoids the need to repeatedly calculate
offsets which ultimately ought to be eliminated pre-RA in order to decrease
register pressure.

Fixes PR9199 and PR23768.

[This is based on Peter Collingbourne's r238473 which was reverted.]

Differential Revision: http://reviews.llvm.org/D13239

Change-Id: I727543c2e94136e0f80b8e22d5642d7b9ee5b458
Author: Peter Collingbourne <peter@pcc.me.uk>
llvm-svn: 249322
2015-10-05 14:49:54 +00:00
Andrew Kaylor 16c4da03d5 Improved the interface of methods commuting operands, improved X86-FMA3 mem-folding&coalescing.
Patch by Slava Klochkov (vyacheslav.n.klochkov@intel.com)

Differential Revision: http://reviews.llvm.org/D11370

llvm-svn: 248735
2015-09-28 20:33:22 +00:00
Cong Hou f9f9ffb98b Scaling up values in ARMBaseInstrInfo::isProfitableToIfCvt() before they are scaled by a probability to avoid precision issue.
In ARMBaseInstrInfo::isProfitableToIfCvt(), there is a simple cost model in which the number of cycles is scaled by a probability to estimate the cost. However, when the number of cycles is small (which is usually the case), there is a precision issue after the computation. To avoid this issue, this patch scales those cycles by 1024 (chosen to make the multiplication a litter faster) before they are scaled by the probability. Other variables are also scaled up for the final comparison.

Differential Revision: http://reviews.llvm.org/D12742

llvm-svn: 248018
2015-09-18 18:19:40 +00:00
Cong Hou c536bd9e73 Pass BranchProbability/BlockMass by value instead of const& as they are small. NFC.
llvm-svn: 247357
2015-09-10 23:10:42 +00:00
Cong Hou b5ef475e5c [ARM] Use BranchProbability::scale() to scale an integer with a probability in ARMBaseInstrInfo.cpp,
Previously in isProfitableToIfCvt() in ARMBaseInstrInfo.cpp, the multiplication between an integer and a branch probability is done manually in an unsafe way that may lead to overflow. This patch corrects those cases by using BranchProbability's member function scale() to avoid overflow (which stores the intermediate result in int64).

Differential Revision: http://reviews.llvm.org/D12295

llvm-svn: 246106
2015-08-26 23:17:52 +00:00
Alex Lorenz e40c8a2b26 PseudoSourceValue: Replace global manager with a manager in a machine function.
This commit removes the global manager variable which is responsible for
storing and allocating pseudo source values and instead it introduces a new
manager class named 'PseudoSourceValueManager'. Machine functions now own an
instance of the pseudo source value manager class.

This commit also modifies the 'get...' methods in the 'MachinePointerInfo'
class to construct pseudo source values using the instance of the pseudo
source value manager object from the machine function.

This commit updates calls to the 'get...' methods from the 'MachinePointerInfo'
class in a lot of different files because those calls now need to pass in a
reference to a machine function to those methods.

This change will make it easier to serialize pseudo source values as it will
enable me to transform the mips specific MipsCallEntry PseudoSourceValue
subclass into two target independent subclasses.

Reviewers: Akira Hatanaka
llvm-svn: 244693
2015-08-11 23:09:45 +00:00
Sanjay Patel 924879ad2c wrap OptSize and MinSize attributes for easier and consistent access (NFCI)
Create wrapper methods in the Function class for the OptimizeForSize and MinSize
attributes. We want to hide the logic of "or'ing" them together when optimizing
just for size (-Os).

Currently, we are not consistent about this and rely on a front-end to always set
OptimizeForSize (-Os) if MinSize (-Oz) is on. Thus, there are 18 FIXME changes here
that should be added as follow-on patches with regression tests.

This patch is NFC-intended: it just replaces existing direct accesses of the attributes
by the equivalent wrapper call.

Differential Revision: http://reviews.llvm.org/D11734

llvm-svn: 243994
2015-08-04 15:49:57 +00:00
James Molloy 6967e5e4a3 Be less conservative about forming IT blocks.
In http://reviews.llvm.org/rL215382, IT forming was made more conservative under
the belief that a flag-setting instruction was unpredictable inside an IT block on ARMv6M.

But actually, ARMv6M doesn't even support IT blocks so that's impossible. In the ARMARM for
v7M, v7AR and v8AR it states that the semantics of such an instruction changes inside an
IT block - it doesn't set the flags. So actually it is fine to use one inside an IT block
as long as the flags register is dead afterwards.

This gives significant performance improvements in a variety of MPEG based workloads.

Differential revision: http://reviews.llvm.org/D11680

llvm-svn: 243869
2015-08-03 09:24:48 +00:00
Daniel Sanders fbdab437f0 Where Triple has a suitable predicate, use it rather than the enum values. NFC.
Reviewers: mcrosier

Subscribers: llvm-commits, rengolin

Differential Revision: http://reviews.llvm.org/D10960

llvm-svn: 241469
2015-07-06 16:33:18 +00:00
Benjamin Kramer e61cbd1f3a Replace copy-pasted debug value skipping with MBB::getLastNonDebugInstr
No functional change intended.

llvm-svn: 240639
2015-06-25 13:28:24 +00:00
Alexander Kornienko f00654e31b Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)
Apparently, the style needs to be agreed upon first.

llvm-svn: 240390
2015-06-23 09:49:53 +00:00
Alexander Kornienko 70bc5f1398 Fixed/added namespace ending comments using clang-tidy. NFC
The patch is generated using this command:

tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
  -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
  llvm/lib/


Thanks to Eugene Kosov for the original patch!

llvm-svn: 240137
2015-06-19 15:57:42 +00:00
Matthias Braun 88e213159a MachineLICM: Use TargetSchedModel instead of just itineraries
This will use Itinieraries if available, but will also work if just a
MCSchedModel is available.

Differential Revision: http://reviews.llvm.org/D10428

llvm-svn: 239658
2015-06-13 03:42:11 +00:00
Ahmed Bougacha c88bf54366 [CodeGen] ArrayRef'ize cond/pred in various TII APIs. NFC.
llvm-svn: 239553
2015-06-11 19:30:37 +00:00
Tim Northover a603c4076c ARM: recommit r237590: allow jump tables to be placed as constant islands.
The original version didn't properly account for the base register
being modified before the final jump, so caused miscompilations in
Chromium and LLVM. I've fixed this and tested with an LLVM self-host
(I don't have the means to build & test Chromium).

The general idea remains the same: in pathological cases jump tables
can be too far away from the instructions referencing them (like other
constants) so they need to be movable.

Should fix PR23627.

llvm-svn: 238680
2015-05-31 19:22:07 +00:00
Michael Kuperstein db0712f986 Use std::bitset for SubtargetFeatures.
Previously, subtarget features were a bitfield with the underlying type being uint64_t. 
Since several targets (X86 and ARM, in particular) have hit or were very close to hitting this bound, switching the features to use a bitset.
No functional change.

The first several times this was committed (e.g. r229831, r233055), it caused several buildbot failures.
Apparently the reason for most failures was both clang and gcc's inability to deal with large numbers (> 10K) of bitset constructor calls in tablegen-generated initializers of instruction info tables. 
This should now be fixed.

llvm-svn: 238192
2015-05-26 10:47:10 +00:00
Peter Collingbourne 7e814d100b Revert r237590, "ARM: allow jump tables to be placed as constant islands."
Caused a miscompile of the Android port of Chromium, details
forthcoming.

llvm-svn: 237972
2015-05-21 23:20:55 +00:00
Matthias Braun 07066cca20 MachineInstr: Remove unused parameter.
llvm-svn: 237726
2015-05-19 21:22:20 +00:00
Matthias Braun fa3872e7ad MachineInstr: Change return value of getOpcode() to unsigned.
This was previously returning int. However there are no negative opcode
numbers and more importantly this was needlessly different from
MCInstrDesc::getOpcode() (which even is the value returned here) and
SDValue::getOpcode()/SDNode::getOpcode().

llvm-svn: 237611
2015-05-18 20:27:55 +00:00
Tim Northover 12c41af07c ARM: allow jump tables to be placed as constant islands.
Previously, they were forced to immediately follow the actual branch
instruction. This was usually OK (the LEAs actually accessing them got emitted
nearby, and weren't usually separated much afterwards). Unfortunately, a
sufficiently nasty phi elimination dumps many instructions right before the
basic block terminator, and this can increase the range too much.

This patch frees them up to be placed as usual by the constant islands pass,
and consequently has to slightly modify the form of TBB/TBH tables to refer to
a PC-relative label at the final jump. The other jump table formats were
already position-independent.

rdar://20813304

llvm-svn: 237590
2015-05-18 17:10:40 +00:00
Tim Northover 4998a47f73 ARM: remove custom jump table UID
We were creating and propagating two separate indices for each jump table (from
back in the mists of time). However, the generic index used by other backends
is sufficient to emit a unique symbol so this was unneeded.

llvm-svn: 237294
2015-05-13 20:28:38 +00:00
Michael Kuperstein c3434b390d Reverting r237234, "Use std::bitset for SubtargetFeatures"
The buildbots are still not satisfied.
MIPS and ARM are failing (even though at least MIPS was expected to pass).

llvm-svn: 237245
2015-05-13 10:28:46 +00:00
Michael Kuperstein aba4a34ef2 Use std::bitset for SubtargetFeatures
Previously, subtarget features were a bitfield with the underlying type being uint64_t. 
Since several targets (X86 and ARM, in particular) have hit or were very close to hitting this bound, switching the features to use a bitset.
No functional change.

The first two times this was committed (r229831, r233055), it caused several buildbot failures. 
At least some of the ARM and MIPS ones were due to gcc/binutils issues, and should now be fixed.

llvm-svn: 237234
2015-05-13 08:27:08 +00:00
Pete Cooper 2127b00cd5 [ARM] optimizeSelect should clear kill flags.
If we move an instruction from one block down to a MOVC and predicate it,
then the original instruction could be moved in to a loop.  In this case,
its invalid for any kill flags to remain on there.

Fails with -verfy-machineinstrs.

rdar://problem/20752113

llvm-svn: 236290
2015-04-30 23:57:47 +00:00
Tim Northover e18d662201 ARM: fix peephole optimisation of TST
We were trying to look through COPY instructions, but only to the next
instruction in a BB and incorrectly anyway. The cases where that would actually
be a good idea are rare enough (and not even tested!) that it's not worth
trying to get right.

rdar://20721342

llvm-svn: 236050
2015-04-28 22:03:55 +00:00
Peter Collingbourne cfee5b04bc ARM: When re-creating a branch via InsertBranch, preserve CPSR flags.
In particular, this preserves the kill flag, which allows the Thumb2 cbn?z
optimization to be applied in cases where a branch has been re-created after
the live variables analysis pass, e.g. by the machine block placement pass.

This appears to be low risk; a number of other targets seem to already be
doing something similar, e.g. AArch64, PowerPC.

Differential Revision: http://reviews.llvm.org/D9184

llvm-svn: 235639
2015-04-23 20:31:32 +00:00
Peter Collingbourne 6529523151 Thumb2: When optimizing for size, do not if-convert branches involving comparisons with zero.
This allows the constant island pass to lower these branches to cbn?z
instructions, resulting in a shorter instruction sequence.

Differential Revision: http://reviews.llvm.org/D9183

llvm-svn: 235638
2015-04-23 20:31:30 +00:00
Michael Kuperstein 29704e7fb4 Revert "Use std::bitset for SubtargetFeatures"
This reverts commit r233055.

It still causes buildbot failures (gcc running out of memory on several platforms, and a self-host failure on arm), although less than the previous time.

llvm-svn: 233068
2015-03-24 12:56:59 +00:00
Michael Kuperstein 774b441b5e Use std::bitset for SubtargetFeatures
Previously, subtarget features were a bitfield with the underlying type being uint64_t. 
Since several targets (X86 and ARM, in particular) have hit or were very close to hitting this bound, switching the features to use a bitset.
No functional change.

The first time this was committed (r229831), it caused several buildbot failures. 
At least some of the ARM ones were due to gcc/binutils issues, and should now be fixed.

Differential Revision: http://reviews.llvm.org/D8542

llvm-svn: 233055
2015-03-24 09:17:25 +00:00
Benjamin Kramer 799003bf8c Re-sort includes with sort-includes.py and insert raw_ostream.h where it's used.
llvm-svn: 232998
2015-03-23 19:32:43 +00:00
Renato Golin 1235060734 [ARM] Add support for ARMV6K subtarget (LLVM)
ARMv6K is another layer between ARMV6 and ARMV6T2. This is the LLVM
side of the changes.

ARMV6 family LLVM implementation.

+-------------------------------------+
| ARMV6                               |
+----------------+--------------------+
| ARMV6M (thumb) | ARMV6K (arm,thumb) | <- From ARMV6K and ARMV6M processors
+----------------+--------------------+    have support for hint instructions
| ARMV6T2 (arm,thumb,thumb2)          |    (SEV/WFE/WFI/NOP/YIELD). They can
+-------------------------------------+    be either real or default to NOP.
| ARMV7 (arm,thumb,thumb2)            |    The two processors also use
+-------------------------------------+    different encoding for them.

Patch by Vinicius Tinti.

llvm-svn: 232468
2015-03-17 11:55:28 +00:00
Eric Christopher 7e70aba1a8 Recommit r231324 with a fix to the ARM execution domain code
to disable lane switching if we don't actually have the instruction
set we want to switch to. Models the earlier check above the
conditional for the pass.

The testcase is one that triggered with the assert that's added
as part of the fix, use it to avoid adding a new testcase as it
highlights the same problem.

llvm-svn: 231539
2015-03-07 00:12:22 +00:00
Michael Kuperstein efd7a96d2e Reverting r229831 due to multiple ARM/PPC/MIPS build-bot failures.
llvm-svn: 229841
2015-02-19 11:38:11 +00:00
Michael Kuperstein ba5b04c798 Use std::bitset for SubtargetFeatures
Previously, subtarget features were a bitfield with the underlying type being uint64_t. 
Since several targets (X86 and ARM, in particular) have hit or were very close to hitting this bound, switching the features to use a bitset.

No functional change.

Differential Revision: http://reviews.llvm.org/D7065

llvm-svn: 229831
2015-02-19 09:01:04 +00:00
Duncan P. N. Exon Smith 2cff9e19a2 ARM: Canonicalize access to function attributes, NFC
Canonicalize access to function attributes to use the simpler API.

getAttributes().getAttribute(AttributeSet::FunctionIndex, Kind)
  => getFnAttribute(Kind)

getAttributes().hasAttribute(AttributeSet::FunctionIndex, Kind)
  => hasFnAttribute(Kind)

llvm-svn: 229220
2015-02-14 02:24:44 +00:00
Jan Wen Voung d21194f712 Fix ARM peephole optimizeCompare to avoid optimizing unsigned cmp to 0.
Summary:
Previously it only avoided optimizing signed comparisons to 0.
Sometimes the DAGCombiner will optimize the unsigned comparisons
to 0 before it gets to the peephole pass, but sometimes it doesn't.

Fix for PR22373.

Test Plan: test/CodeGen/ARM/sub-cmp-peephole.ll

Reviewers: jfb, manmanren

Subscribers: aemerson, llvm-commits

Differential Revision: http://reviews.llvm.org/D7274

llvm-svn: 227809
2015-02-02 16:56:50 +00:00
Mehdi Amini 22e59748ef Peephole opt needs optimizeSelect() to keep track of newly created MIs
Peephole optimizer is scanning a basic block forward. At some point it 
needs to answer the question "given a pointer to an MI in the current 
BB, is it located before or after the current instruction".
To perform this, it keeps a set of the MIs already seen during the scan, 
if a MI is not in the set, it is assumed to be after.
It means that newly created MIs have to be inserted in the set as well.

This commit passes the set as an argument to the target-dependent 
optimizeSelect() so that it can properly update the set with the 
(potentially) newly created MIs.

llvm-svn: 225772
2015-01-13 07:07:13 +00:00
Tim Northover 650b0ee53b ARM: add @llvm.arm.space intrinsic for testing ConstantIslands.
Creating tests for the ConstantIslands pass is very difficult, since it depends
on precise layout details. Having the ability to precisely inject a number of
bytes into the stream helps greatly.

llvm-svn: 221903
2014-11-13 17:58:48 +00:00
Tom Roeder eb7a303d1b Add Forward Control-Flow Integrity.
This commit adds a new pass that can inject checks before indirect calls to
make sure that these calls target known locations. It supports three types of
checks and, at compile time, it can take the name of a custom function to call
when an indirect call check fails. The default failure function ignores the
error and continues.

This pass incidentally moves the function JumpInstrTables::transformType from
private to public and makes it static (with a new argument that specifies the
table type to use); this is so that the CFI code can transform function types
at call sites to determine which jump-instruction table to use for the check at
that site.

Also, this removes support for jumptables in ARM, pending further performance
analysis and discussion.

Review: http://reviews.llvm.org/D4167
llvm-svn: 221708
2014-11-11 21:08:02 +00:00
Benjamin Kramer 2c3778dc51 Remove a compiler bug workaround from 2007. The affected versions of gcc are long gone.
NFC.

llvm-svn: 219433
2014-10-09 19:50:39 +00:00
Tim Northover 5d72c5de02 ARM: allow copying of CPSR when all else fails.
As with x86 and AArch64, certain situations can arise where we need to spill
CPSR in the middle of a calculation. These should be avoided where possible
(MRS/MSR is rather expensive), which ARM is actually better at than the other
two since it tries to Glue defs to uses, but as a last ditch effort, copying is
better than crashing.

rdar://problem/18011155

llvm-svn: 218789
2014-10-01 19:21:03 +00:00
Robin Morisset 039781ef26 Fix typos in comments, NFC
Summary: Just fixing comments, no functional change.

Test Plan: N/A

Reviewers: jfb

Subscribers: mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D5130

llvm-svn: 216784
2014-08-29 21:53:01 +00:00
Quentin Colombet d358e84d9c [ARM] Move the implementation of the target hooks related to copy-related
instruction from ARMInstrInfo to ARMBaseInstrInfo.
That way, thumb mode can also benefit from the advanced copy optimization.

<rdar://problem/12702965>

llvm-svn: 216274
2014-08-22 18:05:22 +00:00
Oliver Stannard 51b1d460cb [ARM] Enable DP copy, load and store instructions for FPv4-SP
The FPv4-SP floating-point unit is generally referred to as
single-precision only, but it does have double-precision registers and
load, store and GPR<->DPR move instructions which operate on them.
This patch enables the use of these registers, the main advantage of
which is that we now comply with the AAPCS-VFP calling convention.
This partially reverts r209650, which added some AAPCS-VFP support,
but did not handle return values or alignment of double arguments in
registers.

This patch also adds tests for Thumb2 code generation for
floating-point instructions and intrinsics, which previously only
existed for ARM.

llvm-svn: 216172
2014-08-21 12:50:31 +00:00
Saleem Abdulrasool 27c78bf131 ARM: try harder to detect non-IT eligible instructions
For many Thumb-1 register register instructions, setting the CPSR is not
permitted inside an IT block.  We would not correctly flag those instructions.
The previous change to identify this scenario was insufficient as it did not
actually catch all the instances.  The current list is formed by manual
inspection of the ARMv6M ARM.

The change to the Thumb2 IT block test is due to the fact that the new more
stringent checking of the MIs results in the If Conversion pass being prevented
from executing (since not all the instructions in the BB are predicable).  This
results in code gen changes.

Thanks to Tim Northover for pointing out that the previous patch was
insufficient and hinting that the use of the v6M ARM would be much easier to use
than the v7 or v8!

llvm-svn: 215382
2014-08-11 20:13:25 +00:00
Saleem Abdulrasool ed8885b402 ARM: correct isPredicable for MULS in ThHUMB mode
The ARM ARM states that CPSR may not be updated by a MUL in thumb mode.  Due to
an ordering of Thumb 2 Size Reduction and If Conversion, we would end up
generating a THUMB MULS inside an IT block.

The If Conversion pass uses the TTI isPredicable method to ensure that it can
transform a Basic Block.  However, because we only check for IT handling on
Thumb2 functions, we may miss some cases.  Even then, it only validates that the
CPSR is not *live* rather than it is not accessed.  This corrects the handling
for that particular case since the same restriction does not hold on the vast
majority of the instructions.

This does prevent the IfConversion optimization from kicking in in certain
cases, but generating correct code is more valuable.  Addresses PR20555.

llvm-svn: 215328
2014-08-10 22:20:37 +00:00
Eric Christopher d913448b38 Remove the TargetMachine forwards for TargetSubtargetInfo based
information and update all callers. No functional change.

llvm-svn: 214781
2014-08-04 21:25:23 +00:00
Akira Hatanaka e5b6e0d231 [stack protector] Fix a potential security bug in stack protector where the
address of the stack guard was being spilled to the stack.

Previously the address of the stack guard would get spilled to the stack if it
was impossible to keep it in a register. This patch introduces a new target
independent node and pseudo instruction which gets expanded post-RA to a
sequence of instructions that load the stack guard value. Register allocator
can now just remat the value when it can't keep it in a register. 

<rdar://problem/12475629>

llvm-svn: 213967
2014-07-25 19:31:34 +00:00
Eric Christopher c1058df66f Move function dependent resetting of a subtarget variable out of the
subtarget. This involved having the movt predicate take the current
function - since we care about size in instruction selection for
whether or not to use movw/movt take the function so we can check
the attributes. This required adding the current MachineFunction to
FastISel and propagating through.

llvm-svn: 212309
2014-07-04 01:55:26 +00:00
Eric Christopher f047bfd115 The hazard recognizer only needs a subtarget, not a target machine
so make it take one. Fix up all users accordingly.

llvm-svn: 210948
2014-06-13 22:38:52 +00:00
Tom Roeder 44cb65fff1 Add a new attribute called 'jumptable' that creates jump-instruction tables for functions marked with this attribute.
It includes a pass that rewrites all indirect calls to jumptable functions to pass through these tables.

This also adds backend support for generating the jump-instruction tables on ARM and X86.
Note that since the jumptable attribute creates a second function pointer for a
function, any function marked with jumptable must also be marked with unnamed_addr.

llvm-svn: 210280
2014-06-05 19:29:43 +00:00
Craig Topper e73658ddbb [C++] Use 'nullptr'.
llvm-svn: 207394
2014-04-28 04:05:08 +00:00
Craig Topper 062a2baef0 [C++] Use 'nullptr'. Target edition.
llvm-svn: 207197
2014-04-25 05:30:21 +00:00
Chandler Carruth d174b72a28 [cleanup] Lift using directives, DEBUG_TYPE definitions, and even some
system headers above the includes of generated '.inc' files that
actually contain code. In a few targets this was already done pretty
consistently, but it wasn't done *really* consistently anywhere. It is
strictly cleaner IMO and necessary in a bunch of places where the
DEBUG_TYPE is referenced from the generated code. Consistency with the
necessary places trumps. Hopefully the build bots are OK with the
movement of intrin.h...

llvm-svn: 206838
2014-04-22 02:03:14 +00:00
Chandler Carruth e96dd8975f [Modules] Make Support/Debug.h modular. This requires it to not change
behavior based on other files defining DEBUG_TYPE, which means it cannot
define DEBUG_TYPE at all. This is actually better IMO as it forces folks
to define relevant DEBUG_TYPEs for their files. However, it requires all
files that currently use DEBUG(...) to define a DEBUG_TYPE if they don't
already. I've updated all such files in LLVM and will do the same for
other upstream projects.

This still leaves one important change in how LLVM uses the DEBUG_TYPE
macro going forward: we need to only define the macro *after* header
files have been #include-ed. Previously, this wasn't possible because
Debug.h required the macro to be pre-defined. This commit removes that.
By defining DEBUG_TYPE after the includes two things are fixed:

- Header files that need to provide a DEBUG_TYPE for some inline code
  can do so by defining the macro before their inline code and undef-ing
  it afterward so the macro does not escape.

- We no longer have rampant ODR violations due to including headers with
  different DEBUG_TYPE definitions. This may be mostly an academic
  violation today, but with modules these types of violations are easy
  to check for and potentially very relevant.

Where necessary to suppor headers with DEBUG_TYPE, I have moved the
definitions below the includes in this commit. I plan to move the rest
of the DEBUG_TYPE macros in LLVM in subsequent commits; this one is big
enough.

The comments in Debug.h, which were hilariously out of date already,
have been updated to reflect the recommended practice going forward.

llvm-svn: 206822
2014-04-21 22:55:11 +00:00
Benjamin Kramer 44a53da346 Spell the specialization namespace correctly.
Not sure why clang didn't diagnose this (GCC does).

llvm-svn: 206117
2014-04-12 18:45:24 +00:00
Benjamin Kramer 30120c0626 Make helper static and place random global into the llvm namespace.
llvm-svn: 206116
2014-04-12 18:39:57 +00:00
Tim Northover 0feb91ef15 ARM: teach LLVM that Cortex-A7 is very similar to A8.
llvm-svn: 205314
2014-04-01 14:10:07 +00:00
Weiming Zhao 0152485679 Fix PR19136: [ARM] Fix Folding SP Update into vpush/vpop
Sicne MBB->computeRegisterLivenes() returns Dead for sub regs like s0,
d0 is used in vpop instead of updating sp, which causes s0 dead before
its use.

This patch checks the liveness of each subreg to make sure the reg is
actually dead.

llvm-svn: 204411
2014-03-20 23:28:16 +00:00
Owen Anderson 16c6bf49b7 Phase 2 of the great MachineRegisterInfo cleanup. This time, we're changing
operator* on the by-operand iterators to return a MachineOperand& rather than
a MachineInstr&.  At this point they almost behave like normal iterators!

Again, this requires making some existing loops more verbose, but should pave
the way for the big range-based for-loop cleanups in the future.

llvm-svn: 203865
2014-03-13 23:12:04 +00:00