3164 Commits

Author SHA1 Message Date
Nirav Dave
be4d3e6292 Improve Aliasing of operations to static alloca
Recommiting after adding check to avoid miscomputing alias information
on addresses of the same base but different subindices.

Memory accesses offset from frame indices may alias, e.g., we
may merge write from function arguments passed on the stack when they
are contiguous. As a result, when checking aliasing, we consider the
underlying frame index's offset from the stack pointer.

Static allocs are realized as stack objects in SelectionDAG, but its
offset is not set until post-DAG causing DAGCombiner's alias check to
consider access to static allocas to frequently alias. Modify isAlias
to consider access between static allocas and access from other frame
objects to be considered aliasing.

Many test changes are included here. Most are fixes for tests which
indirectly relied on our aliasing ability and needed to be modified to
preserve their original intent.

The remaining tests have minor improvements due to relaxed
ordering. The exception is CodeGen/X86/2011-10-19-widen_vselect.ll
which has a minor degradation dispite though the pre-legalized DAG is
improved.

Reviewers: rnk, mkuper, jonpa, hfinkel, uweigand

Reviewed By: rnk

Subscribers: sdardis, nemanjai, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D33345

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308025 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-14 13:56:21 +00:00
Diana Picus
a6ef55bfe2 [ARM] GlobalISel: Support G_BRCOND
Insert a TSTri to set the flags and a Bcc to branch based on their
values. This is a bit inefficient in the (common) cases where the
condition for the branch comes from a compare right before the branch,
since we set the flags both as part of the compare lowering and as part
of the branch lowering. We're going to live with that until we settle on
a principled way to handle this kind of situation, which occurs with
other patterns as well (combines might be the way forward here).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308009 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-14 09:46:06 +00:00
Diana Picus
d4a91bbb19 [ARM] GlobalISel: Support G_BR
This boils down to not crashing in reg bank select due to the lack of
register operands on this instruction, and adding some tests. The
instruction selection is already covered by the TableGen'erated code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307904 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-13 11:09:34 +00:00
Evandro Menezes
0dedcfc77f [CodeGen] Add dependency printer
Add SDep printer to make debugging sessions more productive.

Differential revision: https://reviews.llvm.org/D35144

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307799 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-12 15:30:59 +00:00
Diana Picus
8577619105 [ARM] GlobalISel: Select s64 G_FCMP
Very similar to how we select s32 G_FCMP, the only thing that is
different is the exact opcodes that we use.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307763 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-12 09:01:54 +00:00
Konstantin Zhuravlyov
8f85685860 Enhance synchscope representation
OpenCL 2.0 introduces the notion of memory scopes in atomic operations to
  global and local memory. These scopes restrict how synchronization is
  achieved, which can result in improved performance.

  This change extends existing notion of synchronization scopes in LLVM to
  support arbitrary scopes expressed as target-specific strings, in addition to
  the already defined scopes (single thread, system).

  The LLVM IR and MIR syntax for expressing synchronization scopes has changed
  to use *syncscope("<scope>")*, where <scope> can be "singlethread" (this
  replaces *singlethread* keyword), or a target-specific name. As before, if
  the scope is not specified, it defaults to CrossThread/System scope.

  Implementation details:
    - Mapping from synchronization scope name/string to synchronization scope id
      is stored in LLVM context;
    - CrossThread/System and SingleThread scopes are pre-defined to efficiently
      check for known scopes without comparing strings;
    - Synchronization scope names are stored in SYNC_SCOPE_NAMES_BLOCK in
      the bitcode.

Differential Revision: https://reviews.llvm.org/D21723



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307722 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-11 22:23:00 +00:00
Diana Picus
85d38e084b [ARM] GlobalISel: Tighten G_FCMP selection test. NFC
Use CHECK-NEXT for the comparison sequence, to make sure we don't get
any unexpected instructions in the middle of our flag manipulation
efforts.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307656 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-11 12:34:33 +00:00
Diana Picus
8ae39dc847 [ARM] GlobalISel: Add reg mapping for s64 G_FCMP
Map the result into GPR and the operands into FPR.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307653 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-11 11:47:45 +00:00
Diana Picus
301859ba89 [ARM] GlobalISel: Tighten legalizer tests. NFC
Make sure that all the legalizer tests where the original instruction
needs to be removed check for the removal. We do this by adding
CHECK-NOT lines before and after the replacement sequence. This won't
catch pathological cases where the instruction remains somewhere in the
middle of the instruction sequence that's supposed to replace it, but
hopefully that won't occur in practice (since ideally we'd be setting
the insert point for the new instruction sequence either before or after
the original instruction and not fiddle with it while building the
sequence).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307647 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-11 10:52:08 +00:00
Diana Picus
f4f832c513 [ARM] GlobalISel: Fix oversight in G_FCMP legalization
We used to forget to erase the original instruction when replacing a
G_FCMP true/false. Fix this bug and make sure the tests check for it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307639 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-11 09:43:51 +00:00
Diana Picus
6845427d1b [ARM] GlobalISel: Legalize s64 G_FCMP
Same as the s32 version, for both hard and soft float.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307633 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-11 08:50:01 +00:00
Matthias Braun
c364d94de8 Revert "[DAG] Improve Aliasing of operations to static alloca"
Reverting as it breaks tramp3d-v4 in the llvm test-suite. I added some
comments to https://reviews.llvm.org/D33345 about it.

This reverts commit r307546.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307589 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-10 20:51:30 +00:00
Nirav Dave
e791f411d3 [DAG] Improve Aliasing of operations to static alloca
Memory accesses offset from frame indices may alias, e.g., we
may merge write from function arguments passed on the stack when they
are contiguous. As a result, when checking aliasing, we consider the
underlying frame index's offset from the stack pointer.

Static allocs are realized as stack objects in SelectionDAG, but its
offset is not set until post-DAG causing DAGCombiner's alias check to
consider access to static allocas to frequently alias. Modify isAlias
to consider access between static allocas and access from other frame
objects to be considered aliasing.

Many test changes are included here. Most are fixes for tests which
indirectly relied on our aliasing ability and needed to be modified to
preserve their original intent.

The remaining tests have minor improvements due to relaxed
ordering. The exception is CodeGen/X86/2011-10-19-widen_vselect.ll
which has a minor degradation dispite though the pre-legalized DAG is
improved.

Reviewers: rnk, mkuper, jonpa, hfinkel, uweigand

Reviewed By: rnk

Subscribers: sdardis, nemanjai, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D33345

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307546 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-10 15:39:41 +00:00
Andrew V. Tischenko
255ac753d5 NFC: I simply added CHECK-LABEL to prevent false matches in the tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307397 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-07 13:41:33 +00:00
Diana Picus
a479e53b55 [ARM] GlobalISel: Select hard G_FCMP for s32
We lower to a sequence consisting of:
- MOVi 0 into a register
- VCMPS to do the actual comparison and set the VFP flags
- FMSTAT to move the flags out of the VFP unit
- MOVCCi to either use the "zero register" that we have previously set
  with the MOVi, or move 1 into the result register, based on the values
  of the flags

As was the case with soft-float, for some predicates (one, ueq) we
actually need two comparisons instead of just one. When that happens, we
generate two VCMPS-FMSTAT-MOVCCi sequences and chain them by means of
using the result of the first MOVCCi as the "zero register" for the
second one. This is a bit overkill, since one comparison followed by
two non-flag-setting conditional moves should be enough. In any case,
the backend manages to CSE one of the comparisons away so it doesn't
matter much.

Note that unlike SelectionDAG and FastISel, we always use VCMPS, and not
VCMPES. This makes the code a lot simpler, and it also seems correct
since the LLVM Lang Ref defines simple true/false returns if the
operands are QNaN's. For SNaN's, even VCMPS throws an Invalid Operand
exception, so they won't be slipping through unnoticed.

Implementation-wise, this introduces a template so we can share the same
code that we use for handling integer comparisons, since the only
differences are in the details (exact opcodes to be used etc). Hopefully
this will be easy to extend to s64 G_FCMP.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307365 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-07 08:39:04 +00:00
Matthias Braun
192187283c RegisterScavenging: Fix PR33687
When scavenging for a use in instruction MI, we will reload after
that instruction and hence cannot spill uses/defs of this instruction.

This fixes http://llvm.org/PR33687

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307352 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-07 03:02:18 +00:00
Diana Picus
b72872894c [ARM] GlobalISel: Map s32 G_FCMP in reg bank select
Map hard G_FCMP operands to FPR and the result to GPR.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307245 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-06 09:57:46 +00:00
Diana Picus
e9e0d4fb83 [ARM] GlobalISel: Legalize G_FCMP for s32
This covers both hard and soft float.

Hard float is easy, since it's just Legal.

Soft float is more involved, because there are several different ways to
handle it based on the predicate: one and ueq need not only one, but two
libcalls to get a result. Furthermore, we have large differences between
the values returned by the AEABI and GNU functions.

AEABI functions return a nice 1 or 0 representing true and respectively
false. GNU functions generally return a value that needs to be compared
against 0 (e.g. for ogt, the value returned by the libcall is > 0 for
true).  We could introduce redundant comparisons for AEABI as well, but
they don't seem easy to remove afterwards, so we do different processing
based on whether or not the result really needs to be compared against
something (and just truncate if it doesn't).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307243 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-06 09:09:33 +00:00
Diana Picus
38c3b330a4 [ARM] GlobalISel: Widen s1, s8, s16 G_CONSTANT
Get the legalizer to widen small constants.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307239 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-06 08:04:16 +00:00
Andrew Zhogin
e54a2b399d [DAGCombiner] visitRotate patch to optimize pair of ROTR/ROTL instructions into one with combined shift operand.
For two ROTR operations with shifts C1, C2; combined shift operand will be (C1 + C2) % bitsize.

Differential revision: https://reviews.llvm.org/D12833


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307179 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-05 17:55:42 +00:00
Andrew Zhogin
d519d29dbb [ARM][test] Added test/CodeGen/ARM/ror.ll test. NFC precommit for D12833.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307103 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-04 19:50:22 +00:00
Eric Christopher
26e9879a19 Remove the default ARMSubtarget from the ARM TargetMachine.
This enables us to ensure better LTO and code generation in the face of module linking.
Remove a report_fatal_error from the TargetMachine and replace it with an assert in ARMSubtarget - and remove the test that depended on the error. The assertion will still fire in the case that we were reporting before, but error reporting needs to be in front end tools if possible for options parsing.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306939 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-01 03:41:53 +00:00
Eric Christopher
ed4cc74af3 Rewrite ARM execute only support to avoid the use of a command line flag and unqualified ARMSubtarget lookup.
Paired with a clang commit to use the new behavior.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306927 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-01 02:55:22 +00:00
Tim Northover
699416df0f GlobalISel: add G_IMPLICIT_DEF instruction.
It looks like there are two target-independent but not GISel instructions that
need legalization, IMPLICIT_DEF and PHI. These are already anomalies since
their operands have important LLTs attached, so to make things more uniform it
seems like a good idea to add generic variants. Starting with G_IMPLICIT_DEF.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306875 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-30 20:27:36 +00:00
Tim Northover
a8b6c543a8 ARM: fix big-endian 64-bit cmpxchg.
On big-endian machines the high and low parts of the value accessed by ldrexd
and strexd are swapped around. To account for this we swap inputs and outputs
in ISelLowering.

Patch by Bharathi Seshadri.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306865 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-30 19:51:02 +00:00
Eric Christopher
271565d7e6 Unified logic for computing target ABI in backend and front end by moving this common code to Support/TargetParser.
Modeled Triple::GNU after front end code (aapcs abi) and  updated tests that expect apcs abi.

Based heavily on a patch by Ana Pazos!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306768 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-30 00:03:54 +00:00
Nikolai Bozhenov
39f5e6d6b0 [NFC] Use stdin for some tests instead of positional argument.
Summary: Otherwise unexpected matches with the path to the tests might happen.

Reviewers: rengolin, spatel, efriedma, RKSimon

Reviewed By: spatel

Subscribers: n.bozhenov, javed.absar, llvm-commits

Patch by Andrei Elovikov <andrei.elovikov@intel.com>

Differential Revision: https://reviews.llvm.org/D32994


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306684 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-29 14:51:54 +00:00
Florian Hahn
d83ceeeedb [ARM] Add tGPRwithpc register class and use it for TBB/THH
Summary:
TBB and THH allow using a Thumb GPR or the PC as destination operand.
A few machine verifier failures where due to those instructions not
expecting PC as destination operand.

Add -verify-machineinstrs to test/CodeGen/ARM/jump-table-tbh.ll to add
test coverage even if expensive checks are disabled.



Reviewers: MatzeB, t.p.northover, jmolloy

Reviewed By: MatzeB

Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D34610

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306654 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-29 08:45:31 +00:00
Kristof Beyls
f41c3c9239 [ARM] Make -mcpu=generic schedule for an in-order core (Cortex-A8).
The benchmarking summarized in
http://lists.llvm.org/pipermail/llvm-dev/2017-May/113525.html showed
this is beneficial for a wide range of cores.

As is to be expected, quite a few small adaptations are needed to the
regressions tests, as the difference in scheduling results in:
- Quite a few small instruction schedule differences.
- A few changes in register allocation decisions caused by different
 instruction schedules.
- A few changes in IfConversion decisions, due to a difference in
 instruction schedule and/or the estimated cost of a branch mispredict.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306514 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-28 07:07:03 +00:00
Diana Picus
a2474d43c4 [ARM] GlobalISel: Support G_SELECT for pointers
All we need to do is mark it as legal, otherwise it's just like s32.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306390 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-27 10:29:50 +00:00
Diana Picus
99b52fe13c [ARM] GlobalISel: Support G_SELECT for i32
* Mark as legal for (s32, i1, s32, s32)
* Map everything into GPRs
* Select to two instructions: a CMP of the condition against 0, to set
  the flags, and a MOVCCr to select between the two inputs based on the
  flags that we've just set

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306382 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-27 09:19:51 +00:00
Tim Northover
5e24d2fee2 GlobalISel: convert buildSequence to use non-deprecated instructions.
G_SEQUENCE is going away soon so as a first step the MachineIRBuilder needs to
be taught how to emulate it with alternatives. We use G_MERGE_VALUES where
possible, and a sequence of G_INSERTs if not.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306119 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-23 16:15:37 +00:00
Kristof Beyls
bfafbd5fbf Don't conditionalize Neon instructions, even in IT blocks.
This has been deprecated since ARMARM v7-AR, release C.b, published back
in 2012.

This also removes test/CodeGen/Thumb2/ifcvt-neon.ll that originally was
introduced to check that conditionalization of Neon instructions did
happen when generating Thumb2. However, the test had evolved and was no
longer testing that. Rather than trying to adapt that test, this commit
introduces test/CodeGen/Thumb2/ifcvt-neon-deprecated.mir, since we can
now use the MIR framework to write nicer/more maintainable tests.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305998 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-22 12:11:38 +00:00
Florian Hahn
7ebe2a2831 [ARM] Add macro fusion for AES instructions.
Summary:
This patch adds a macro fusion using CodeGen/MacroFusion.cpp to pair AES
instructions back to back and adds FeatureFuseAES to enable the feature.

Reviewers: evandro, javed.absar, rengolin, t.p.northover

Reviewed By: javed.absar

Subscribers: aemerson, mgorny, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D34142

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305988 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-22 09:39:36 +00:00
Dean Michael Berris
e479ac85d5 [XRay] Reduce synthetic references emitted by XRay
Summary:
When we're building with XRay instrumentation, we use a trick that
preserves references from the function to a function sled index. This
index table lives in a separate section, and without this trick the
linker is free to garbage-collect this section and all the segments it
refers to. Until we're able to tell the linkers to preserve these
sections, we use this reference trick to keep around both the index and
the entries in the instrumentation map.

Before this change we emitted both a synthetic reference to the label in
the instrumentation map, and to the entry in the function map index.
This change removes the first synthetic reference and only emits one
synthetic reference to the index -- the index entry has the references
to the labels in the instrumentation map, so the linker will still
preserve those if the function itself is preserved.

This reduces the amount of synthetic references we emit from 16 bytes to
just 8 bytes in x86_64, and similarly to other platforms.

Reviewers: dblaikie

Subscribers: javed.absar, kpw, pelikan, llvm-commits

Differential Revision: https://reviews.llvm.org/D34340

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305880 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-21 06:39:42 +00:00
Tim Northover
f37b0dbf16 DAG: correctly legalize UMULO.
We were incorrectly sign extending into the high word (as you would for
SMULO) when legalizing UMULO in terms of a wider full multiplication.

Patch by James Duley.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305800 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-20 15:01:38 +00:00
Alexandros Lamprineas
46e03a371d [ARM] Support constant pools in data when generating execute-only code.
Resubmission of r305387, which was reverted at r305390. The Address
Sanitizer caught a stack-use-after-scope of a Twine variable. This
is now fixed by passing the Twine directly as a function parameter.

The ARM backend asserts against constant pool lowering when it generates
execute-only code in order to prevent the generation of constant pools in
the text section. It appears that target independent optimizations might
generate DAG nodes that represent constant pools. By lowering such nodes
as global addresses we don't violate the semantics of execute-only code
and also it is guaranteed that execute-only behaves correct with the
position-independent addressing modes that support execute-only code.

Differential Revision: https://reviews.llvm.org/D33773

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305776 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-20 07:20:52 +00:00
Diana Picus
afb808fd9e [ARM] GlobalISel: Support G_ICMP for s8 and s16
Widen to s32 (like all other binary ops).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305683 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-19 11:47:28 +00:00
Diana Picus
df1f7afc1e [ARM] GlobalISel: Support G_ICMP for i32 and pointers
Add support throughout the pipeline:
- mark as legal for s32 and pointers
- map to GPRs
- lower to a sequence of instructions, which moves 0 or 1 into the
  result register based on the flags set by a CMPrr

We have copied from FastISel a helper function which maps CmpInst
predicates into ARMCC codes. Ideally, we should be able to move it
somewhere that both FastISel and GlobalISel can use.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305672 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-19 09:40:51 +00:00
Matthias Braun
cd03942492 RegScavenging: Add scavengeRegisterBackwards()
Re-apply r276044/r279124/r305516. Fixed a problem where we would refuse
to place spills as the very first instruciton of a basic block and thus
artifically increase pressure (test in
test/CodeGen/PowerPC/scavenging.mir:spill_at_begin)

This is a variant of scavengeRegister() that works for
enterBasicBlockEnd()/backward(). The benefit of the backward mode is
that it is not affected by incomplete kill flags.

This patch also changes
PrologEpilogInserter::doScavengeFrameVirtualRegs() to use the register
scavenger in backwards mode.

Differential Revision: http://reviews.llvm.org/D21885

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305625 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-17 02:08:18 +00:00
Matthias Braun
bd1a266898 Revert "RegScavenging: Add scavengeRegisterBackwards()"
Revert because of reports of some PPC input starting to spill when it
was predicted that it wouldn't and no spillslot was reserved.

This reverts commit r305516.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305566 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-16 17:48:08 +00:00
Matthias Braun
02688b00ef RegScavenging: Add scavengeRegisterBackwards()
Re-apply r276044/r279124. Trying to reproduce or disprove the ppc64
problems reported in the stage2 build last time, which I cannot
reproduce right now.

This is a variant of scavengeRegister() that works for
enterBasicBlockEnd()/backward(). The benefit of the backward mode is
that it is not affected by incomplete kill flags.

This patch also changes
PrologEpilogInserter::doScavengeFrameVirtualRegs() to use the register
scavenger in backwards mode.

Differential Revision: http://reviews.llvm.org/D21885

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305516 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-15 22:14:55 +00:00
Arnold Schwaighofer
00cc11273b ISel: Fix FastISel of swifterror values
The code assumed that we process instructions in basic block order.  FastISel
processes instructions in reverse basic block order. We need to pre-assign
virtual registers before selecting otherwise we get def-use relationships wrong.

This only affects code with swifterror registers.

rdar://32659327

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305484 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-15 17:34:42 +00:00
Diana Picus
39c5686a1f [ARM] GlobalISel: Add support for i32 modulo
Add support for modulo for targets that have hardware division and for
those that don't. When hardware division is not available, we have to
choose the correct libcall to use. This is generally straightforward,
except for AEABI.

The AEABI variant is trickier than the other libcalls because it
returns { quotient, remainder }, instead of just one value like the
other libcalls that we've seen so far. Therefore, we need to use custom
lowering for it. However, we don't want to have too much special code,
so we refactor the target-independent code in the legalizer by adding a
helper for replacing an instruction with a libcall. This helper is used
by the legalizer itself when dealing with simple calls, and also by the
custom ARM legalization for the more complicated AEABI divmod calls.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305459 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-15 10:53:31 +00:00
Diana Picus
f39ec45e29 [ARM] GlobalISel: Lower only homogeneous struct args
Lowering mixed struct args, params and returns used G_INSERT, which is a
bit more convoluted to support through the entire pipeline. Since they
don't occur that often in practice, it's probably wiser to leave them
out until later.

Meanwhile, we can lower homogeneous structs using G_MERGE_VALUES, which
has good support in the legalizer. These occur e.g. as the return of
__aeabi_idivmod, so it's nice to be able to support them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305458 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-15 09:42:02 +00:00
Alexandros Lamprineas
b9bba8a9e8 Revert "[ARM] Support constant pools in data when generating execute-only code."
This reverts commit 3a204faa09.

I've upset a buildbot which runs the address sanitizer:
ERROR: AddressSanitizer: stack-use-after-scope
lib/Target/ARM/ARMISelLowering.cpp:2690
That Twine variable is used illegally.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305390 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-14 15:00:08 +00:00
Alexandros Lamprineas
3a204faa09 [ARM] Support constant pools in data when generating execute-only code.
The ARM backend asserts against constant pool lowering when it generates
execute-only code in order to prevent the generation of constant pools in
the text section. It appears that target independent optimizations might
generate DAG nodes that represent constant pools. By lowering such nodes
as global addresses we don't violate the semantics of execute-only code
and also it is guaranteed that execute-only behaves correct with the
position-independent addressing modes that support execute-only code.

Differential Revision: https://reviews.llvm.org/D33773

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305387 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-14 13:22:41 +00:00
Florian Hahn
50963b3b75 Align definition of DW_OP_plus with DWARF spec [3/3]
Summary:
This patch is part of 3 patches that together form a single patch, but must be introduced in stages in order not to break things.
 
The way that LLVM interprets DW_OP_plus in DIExpression nodes is basically that of the DW_OP_plus_uconst operator since LLVM expects an unsigned constant operand. This unnecessarily restricts the DW_OP_plus operator, preventing it from being used to describe the evaluation of runtime values on the expression stack. These patches try to align the semantics of DW_OP_plus and DW_OP_minus with that of the DWARF definition, which pops two elements off the expression stack, performs the operation and pushes the result back on the stack.
 
This is done in three stages:
• The first patch (LLVM) adds support for DW_OP_plus_uconst.
• The second patch (Clang) contains changes all its uses from DW_OP_plus to DW_OP_plus_uconst.
• The third patch (LLVM) changes the semantics of DW_OP_plus and DW_OP_minus to be in line with its DWARF meaning. This patch includes the bitcode upgrade from legacy DIExpressions.

Patch by Sander de Smalen.

Reviewers: echristo, pcc, aprantl

Reviewed By: aprantl

Subscribers: fhahn, javed.absar, aprantl, llvm-commits

Differential Revision: https://reviews.llvm.org/D33894

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305386 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-14 13:14:38 +00:00
Oliver Stannard
8475234d5e [ARM] Add scheduling classes for VFNM[AS]
The VFNM[AS] instructions did not have scheduling information attached, which
was causing assertion failures with the Cortex-A57 scheduling model and
-fp-contract=fast, because the Cortex-A57 sched model claims to be complete.

Differential Revision: https://reviews.llvm.org/D34139



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305288 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-13 13:04:32 +00:00
Geoff Berry
57098b0fe9 [SelectionDAG] Allow sin/cos -> sincos optimization on GNU triples w/ just -fno-math-errno
Summary:
This change enables the sin(x) cos(x) -> sincos(x) optimization on GNU
target triples.  This optimization was being inhibited when -ffast-math
wasn't set because sincos in GLibC does not set errno, while sin and cos
do.  However, this optimization will only run if the attributes on the
sin/cos calls include readnone, which is how clang represents the fact
that it doesn't care about the errno values set by these functions (via
the -fno-math-errno flag).

Reviewers: hfinkel, bogner

Subscribers: mcrosier, javed.absar, llvm-commits, paul.redmond

Differential Revision: https://reviews.llvm.org/D32921

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305204 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-12 17:15:41 +00:00