Commit Graph

22176 Commits

Author SHA1 Message Date
Daniel Sanders
e0180ef4b8 [globalisel] Change LLT constructor string into an LLT subclass that knows how to generate it.
Summary:
This will allow future patches to inspect the details of the LLT. The implementation is now split between
the Support and CodeGen libraries to allow TableGen to use this class without introducing layering concerns.

Thanks to Ahmed Bougacha for finding a reasonable way to avoid the layering issue and providing the version of this patch without that problem.

Reviewers: t.p.northover, qcolombet, rovka, aditya_nandakumar, ab, javed.absar

Subscribers: arsenm, nhaehnle, mgorny, dberris, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D30046

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296474 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-28 14:21:31 +00:00
Sanjoy Das
9868da3b2d [ImplicitNullCheck] Add alias analysis usage
Summary:
With this change ImplicitNullCheck optimization uses alias analysis
and can use load/store memory access for implicit null check if there
are other load/store before but memory accesses do not alias.

Patch by Serguei Katkov!

Reviewers: sanjoy

Reviewed By: sanjoy

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30331

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296440 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-28 07:04:49 +00:00
Matthias Braun
73ddbb7dff Revert "Add MIR-level outlining pass"
Revert Machine Outliner for now, as it breaks the asan bot.

This reverts commit r296418.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296426 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-28 02:24:30 +00:00
Matthias Braun
c043a889f1 Add MIR-level outlining pass
This is a patch for the outliner described in the RFC at:
http://lists.llvm.org/pipermail/llvm-dev/2016-August/104170.html

The outliner is a code-size reduction pass which works by finding
repeated sequences of instructions in a program, and replacing them with
calls to functions. This is useful to people working in low-memory
environments, where sacrificing performance for space is acceptable.

This adds an interprocedural outliner directly before printing assembly.
For reference on how this would work, this patch also includes X86
target hooks and an X86 test.

The outliner is run like so:

clang -mno-red-zone -mllvm -enable-machine-outliner file.c

Patch by Jessica Paquette<jpaquette@apple.com>!

rdar://29166825

Differential Revision: https://reviews.llvm.org/D26872

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296418 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-28 00:33:32 +00:00
Michael Kuperstein
1872f69aec [CGP] Split some critical edges coming out of indirect branches
Splitting critical edges when one of the source edges is an indirectbr
is hard in general (because it requires changing the memory the indirectbr
reads). But if a block only has a single indirectbr predecessor (which is
the common case), we can simulate splitting that edge by splitting
the destination block, and retargeting the *direct* branches.

This is motivated by the use of computed gotos in python 2.7: PyEval_EvalFrame()
ends up using an indirect branch with ~100 successors, and passing a constant to
each of those. Since MachineSink can't break indirect critical edges on demand
(and doing this in MIR doesn't look feasible), this causes us to emit about ~100
defs of registers containing constants, which we in the predecessor block, where
only one of those constants is used in each successor. So, at each computed goto,
we needlessly spill about a 100 constants to stack. The end result is that a
clang-compiled python interpreter can be about ~2.5x slower on a simple python
reduction loop than a gcc-compiled interpreter.

Differential Revision: https://reviews.llvm.org/D29916


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296416 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-28 00:11:34 +00:00
Zachary Turner
d9b4aa7542 [PDB] Make streams carry their own endianness.
Before the endianness was specified on each call to read
or write of the StreamReader / StreamWriter, but in practice
it's extremely rare for streams to have data encoded in
multiple different endiannesses, so we should optimize for the
99% use case.

This makes the code cleaner and more general, but otherwise
has NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296415 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-28 00:04:07 +00:00
Eugene Zelenko
90d9920fc9 [CodeGen] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296404 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-27 22:45:06 +00:00
Arnold Schwaighofer
e4e218c802 ISel: We need to notify FastIS of the IMPLICIT_DEF we created in createSwiftErrorEntriesInEntryBlock
Otherwise, it will insert instructions before it.

rdar://30536186

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296395 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-27 22:12:06 +00:00
Zachary Turner
2219387eaf [PDB] Partial resubmit of r296215, which improved PDB Stream Library.
This was reverted because it was breaking some builds, and
because of incorrect error code usage.  Since the CL was
large and contained many different things, I'm resubmitting
it in pieces.

This portion is NFC, and consists of:

1) Renaming classes to follow a consistent naming convention.
2) Fixing the const-ness of the interface methods.
3) Adding detailed doxygen comments.
4) Fixing a few instances of passing `const BinaryStream& X`.  These
   are now passed as `BinaryStreamRef X`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296394 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-27 22:11:43 +00:00
Matt Arsenault
68c622048b Revert "DAG: Check if extract_vector_elt is legal or custom"
This reverts r295782. This could potentially result in some
legalization loops and I avoided the need for this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296393 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-27 21:59:07 +00:00
Simon Pilgrim
e9bce87a93 [X86][SSE] Attempt to extract vector elements through target shuffles
DAGCombiner already supports peeking thorough shuffles to improve vector element extraction, but legalization often leaves us in situations where we need to extract vector elements after shuffles have already been lowered.

This patch adds support for VECTOR_EXTRACT_ELEMENT/PEXTRW/PEXTRB instructions to attempt to handle target shuffles as well. I've covered some basic scenarios including handling shuffle mask scaling and the implicit zero-extension of PEXTRW/PEXTRB, there is more that could be done here (that I've mentioned in TODOs) but I haven't found many cases where its worth it.

Differential Revision: https://reviews.llvm.org/D30176

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296381 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-27 21:01:57 +00:00
Taewook Oh
6a73128f15 [TailDuplicator] Maintain DebugLoc for branch instructions
Summary: Existing implementation of duplicateSimpleBB function drops DebugLoc metadata of branch instructions during the transformation. This patch addresses this issue by making newly created branch instructions to keep the metadata of replaced branch instructions.

Reviewers: qcolombet, craig.topper, aprantl, MatzeB, sanjoy, dblaikie

Reviewed By: dblaikie

Subscribers: dblaikie, llvm-commits

Differential Revision: https://reviews.llvm.org/D30026

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296371 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-27 19:30:01 +00:00
Artur Pilipenko
85f508cd9d [DAGCombine] Fix for a load combine bug with non-zero offset patterns on BE targets
This pattern is essentially a i16 load from p+1 address:

  %p1.i16 = bitcast i8* %p to i16*
  %p2.i8 = getelementptr i8, i8* %p, i64 2
  %v1 = load i16, i16* %p1.i16
  %v2.i8 = load i8, i8* %p2.i8
  %v2 = zext i8 %v2.i8 to i16
  %v1.shl = shl i16 %v1, 8
  %res = or i16 %v1.shl, %v2

Current implementation would identify %v1 load as the first byte load and would mistakenly emit a i16 load from %p1.i16 address. This patch adds a check that the first byte is loaded from a non-zero offset of the first load address. This way this address can be used as the base address for the combined value. Otherwise just give up combining.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296336 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-27 13:04:23 +00:00
Artur Pilipenko
f85432589b [DAGCombine] NFC. MatchLoadCombine extract MemoryByteOffset lambda helper
This refactoring will simplify the upcoming change to fix the bug in folding patterns with non-zero offsets on BE targets.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296332 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-27 11:42:54 +00:00
Artur Pilipenko
0003ac947f [DAGCombine] NFC. MatchLoadCombine remember the first byte provider, not the load node
This refactoring will simplify the upcoming change to fix a bug in folding patterns with non-zero offsets on BE targets.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296331 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-27 11:40:14 +00:00
Daniel Jasper
e5e8f2aec1 Revert "[CGP] Split some critical edges coming out of indirect branches"
This reverts commit r296149 as it leads to crashes when compiling for
PPC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296295 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-26 11:09:12 +00:00
Nirav Dave
b89cc7e5e3 Revert "In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled."
This reverts commit r296252 until 256-bit operations are more efficiently generated in X86.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296279 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-26 01:27:32 +00:00
Craig Topper
6a0edd3bec [ExecutionDepsFix] Don't make copies of LiveReg objects when collecting operands for soft instructions
Summary:
While collecting operands we make copies of the LiveReg objects which are stored in the LiveRegs array. If the instruction uses the same register multiple times we end up with multiple copies. Later we iterate through the collected list of LiveReg objects and merge DomainValues. In the process of doing this the merge function can change the contents of the original LiveReg object in the LiveRegs array, but not the copies that have been made. So when we get to the second usage of the register we end up seeing a stale copy of the LiveReg object.

To fix this I've stopped copying and now just store a pointer to the original LiveReg object. Another option might be to avoid adding the same register to the Regs array twice, but this approach seemed simpler.

The included test case exposes this bug due to an AVX-512 masked OR instruction using the same register for the passthru operand and one of the inputs to the OR operation.

Fixes PR30284.

Reviewers: RKSimon, stoklund, MatzeB, spatel, myatsina

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30242

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296260 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-25 18:12:25 +00:00
Artyom Skrobov
cc3dbb4073 No need to copy the variable [NFC]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296259 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-25 17:18:09 +00:00
NAKAMURA Takumi
96678fa6d8 Revert r296215, "[PDB] General improvements to Stream library." and followings.
r296215, "[PDB] General improvements to Stream library."
r296217, "Disable BinaryStreamTest.StreamReaderObject temporarily."
r296220, "Re-enable BinaryStreamTest.StreamReaderObject."
r296244, "[PDB] Disable some tests that are breaking bots."
r296249, "Add static_cast to silence -Wc++11-narrowing."

std::errc::no_buffer_space should be used for OS-oriented errors for socket transmission.
(Seek discussions around llvm/xray.)

I could substitute s/no_buffer_space/others/g, but I revert whole them ATM.

Could we define and use LLVM errors there?

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296258 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-25 17:04:23 +00:00
Nirav Dave
32147cef64 In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Recommiting after fixup of 32-bit aliasing sign offset bug in DAGCombiner.

    * Simplify Consecutive Merge Store Candidate Search

    Now that address aliasing is much less conservative, push through
    simplified store merging search and chain alias analysis which only
    checks for parallel stores through the chain subgraph. This is cleaner
    as the separation of non-interfering loads/stores from the
    store-merging logic.

    When merging stores search up the chain through a single load, and
    finds all possible stores by looking down from through a load and a
    TokenFactor to all stores visited.

    This improves the quality of the output SelectionDAG and the output
    Codegen (save perhaps for some ARM cases where we correctly constructs
    wider loads, but then promotes them to float operations which appear
    but requires more expensive constant generation).

    Some minor peephole optimizations to deal with improved SubDAG shapes (listed below)

    Additional Minor Changes:

      1. Finishes removing unused AliasLoad code

      2. Unifies the chain aggregation in the merged stores across code
         paths

      3. Re-add the Store node to the worklist after calling
         SimplifyDemandedBits.

      4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is
         arbitrary, but seems sufficient to not cause regressions in
         tests.

      5. Remove Chain dependencies of Memory operations on CopyfromReg
         nodes as these are captured by data dependence

      6. Forward loads-store values through tokenfactors containing
          {CopyToReg,CopyFromReg} Values.

      7. Peephole to convert buildvector of extract_vector_elt to
         extract_subvector if possible (see
         CodeGen/AArch64/store-merge.ll)

      8. Store merging for the ARM target is restricted to 32-bit as
         some in some contexts invalid 64-bit operations are being
         generated. This can be removed once appropriate checks are
         added.

    This finishes the change Matt Arsenault started in r246307 and
    jyknight's original patch.

    Many tests required some changes as memory operations are now
    reorderable, improving load-store forwarding. One test in
    particular is worth noting:

      CodeGen/PowerPC/ppc64-align-long-double.ll - Improved load-store
      forwarding converts a load-store pair into a parallel store and
      a memory-realized bitcast of the same value. However, because we
      lose the sharing of the explicit and implicit store values we
      must create another local store. A similar transformation
      happens before SelectionDAG as well.

    Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296252 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-25 11:43:58 +00:00
Junmo Park
c236d01938 Minor code cleanup. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296222 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-25 01:50:45 +00:00
Zachary Turner
5433d115a4 [PDB] General improvements to Stream library.
This adds various new functionality and cleanup surrounding the
use of the Stream library.  Major changes include:

* Renaming of all classes for more consistency / meaningfulness
* Addition of some new methods for reading multiple values at once.
* Full suite of unit tests for reader / writer functionality.
* Full set of doxygen comments for all classes.
* Streams now store their own endianness.
* Fixed some bugs in a few of the classes that were discovered
  by the unit tests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296215 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-25 00:44:30 +00:00
Zachary Turner
40ea28492e [PDB] Rename Stream related source files.
This is part of a larger effort to get the Stream code moved
up to Support.  I don't want to do it in one large patch, in
part because the changes are so big that it will treat everything
as file deletions and add, losing history in the process.
Aside from that though, it's just a good idea in general to
make small changes.

So this change only changes the names of the Stream related
source files, and applies necessary source fix ups.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296211 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-25 00:33:34 +00:00
Dan Gohman
8f5a7d69cc [WebAssembly] Add support for using a wasm global for the stack pointer.
This replaces the __stack_pointer variable which was allocated in linear
memory.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296201 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 23:46:05 +00:00
Dan Gohman
53ff96ab08 [WebAssembly] Basic support for Wasm object file encoding.
With the "wasm32-unknown-unknown-wasm" triple, this allows writing out
simple wasm object files, and is another step in a larger series toward
migrating from ELF to general wasm object support. Note that this code
and the binary format itself is still experimental.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296190 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 23:18:00 +00:00
Stanislav Mekhanoshin
fef0dbe59c Revert "Correct register pressure calculation in presence of subregs"
This reverts commit r296009. It broke one out of tree target and also
does not account for all partial lines added or removed when calculating
PressureDiff.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296182 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 21:56:16 +00:00
Tim Northover
e3a136c5b5 GlobalISel: check for CImm rather than Imm on G_CONSTANTs.
All G_CONSTANTS created by the MachineIRBuilder have an operand of type CImm
(i.e. a ConstantInt), so that's what the selector needs to look for.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296176 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 21:21:38 +00:00
Eli Friedman
0ee8e563c9 [CodeGenPrepare] Make -addr-sink-using-gep work with address spaces.
When we construct addressing modes, we use isNoopAddrSpaceCast to ignore
addrspacecast instructions. Make sure we insert the correct addrspacecast
when we reconstruct the addressing mode.

Differential Revision: https://reviews.llvm.org/D30114



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296167 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 20:51:36 +00:00
Michael Kuperstein
98ee128c8e [CGP] Split some critical edges coming out of indirect branches
Splitting critical edges when one of the source edges is an indirectbr
is hard in general (because it requires changing the memory the indirectbr
reads). But if a block only has a single indirectbr predecessor (which is
the common case), we can simulate splitting that edge by splitting
the destination block, and retargeting the *direct* branches.

This is motivated by the use of computed gotos in python 2.7: PyEval_EvalFrame()
ends up using an indirect branch with ~100 successors, and passing a constant to
each of those. Since MachineSink can't break indirect critical edges on demand
(and doing this in MIR doesn't look feasible), this causes us to emit about ~100
defs of registers containing constants, which we in the predecessor block, where
only one of those constants is used in each successor. So, at each computed goto,
we needlessly spill about a 100 constants to stack. The end result is that a
clang-compiled python interpreter can be about ~2.5x slower on a simple python
reduction loop than a gcc-compiled interpreter.

Differential Revision: https://reviews.llvm.org/D29916


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296149 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 18:41:32 +00:00
Sanjay Patel
9a9478ccb0 [DAGCombiner] add missing folds for scalar select of {-1,0,1}
The motivation for filling out these select-of-constants cases goes back to D24480, 
where we discussed removing an IR fold from add(zext) --> select. And that goes back to:
https://reviews.llvm.org/rL75531
https://reviews.llvm.org/rL159230

The idea is that we should always canonicalize patterns like this to a select-of-constants 
in IR because that's the smallest IR and the best for value tracking. Note that we currently 
do the opposite in some cases (like the cases in *this* patch). Ie, the proposed folds in 
this patch already exist in InstCombine today:
https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/InstCombine/InstCombineSelect.cpp#L1151

As this patch shows, most targets generate better machine code for simple ext/add/not ops 
rather than a select of constants. So the follow-up steps to make this less of a patchwork 
of special-case folds and missing IR canonicalization:

1. Have DAGCombiner convert any select of constants into ext/add/not ops.
2  Have InstCombine canonicalize in the other direction (create more selects).

Differential Revision: https://reviews.llvm.org/D30180


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296137 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 17:17:33 +00:00
Daniel Sanders
bf21af7b42 [globalisel] Decouple src pattern operands from dst pattern operands.
Summary:
This isn't testable for AArch64 by itself so this patch also adds
support for constant immediates in the pattern and physical
register uses in the result.

The new IntOperandMatcher matches the constant in patterns such as
'(set $rd:GPR32, (G_XOR $rs:GPR32, -1))'. It's always safe to fold
immediates into an instruction so this is the first rule that will match
across multiple BB's.

The Renderer hierarchy is responsible for adding operands to the result
instruction. Renderers can copy operands (CopyRenderer) or add physical
registers (in particular %wzr and %xzr) to the result instruction
in any order (OperandMatchers now import the operand names from
SelectionDAG to allow renderers to access any operand). This allows us to
emit the result instruction for:
  %1 = G_XOR %0, -1 --> %1 = ORNWrr %wzr, %0
  %1 = G_XOR -1, %0 --> %1 = ORNWrr %wzr, %0
although the latter is untested since the matcher/importer has not been
taught about commutativity yet.

Added BuildMIAction which can build new instructions and mutate them where
possible. W.r.t the mutation aspect, MatchActions are now told the name of
an instruction they can recycle and BuildMIAction will emit mutation code
when the renderers are appropriate. They are appropriate when all operands
are rendered using CopyRenderer and the indices are the same as the matcher.
This currently assumes that all operands have at least one matcher.

Finally, this change also fixes a crash in
AArch64InstructionSelector::select() caused by an immediate operand
passing isImm() rather than isCImm(). This was uncovered by the other
changes and was detected by existing tests.

Depends on D29711

Reviewers: t.p.northover, ab, qcolombet, rovka, aditya_nandakumar, javed.absar

Reviewed By: rovka

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

Differential Revision: https://reviews.llvm.org/D29712

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296131 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 15:43:30 +00:00
Justin Bogner
dde79d7c7b Add missing initialization for MachineOptimizationRemarkEmitter
This was missed in r293110.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296096 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 07:42:35 +00:00
Craig Topper
732985157f [ExecutionDepsFix] Use range-based for loop. NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296093 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 06:38:24 +00:00
Michael Kuperstein
969577f54d Revert r269060 to pacify bots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296064 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 01:22:19 +00:00
Michael Kuperstein
8981fc9888 [CGP] Split some critical edges coming out of indirect branches
Splitting critical edges when one of the source edges is an indirectbr
is hard in general (because it requires changing the memory the indirectbr
reads). But if a block only has a single indirectbr predecessor (which is
the common case), we can simulate splitting that edge by splitting
the destination block, and retargeting the *direct* branches.

This is motivated by the use of computed gotos in python 2.7: PyEval_EvalFrame()
ends up using an indirect branch with ~100 successors, and passing a constant to
each of those. Since MachineSink can't break indirect critical edges on demand
(and doing this in MIR doesn't look feasible), this causes us to emit about ~100
defs of registers containing constants, which we in the predecessor block, where
only one of those constants is used in each successor. So, at each computed goto,
we needlessly spill about a 100 constants to stack. The end result is that a
clang-compiled python interpreter can be about ~2.5x slower on a simple python
reduction loop than a gcc-compiled interpreter.

Differential Revision: https://reviews.llvm.org/D29916


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296060 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 00:56:21 +00:00
Ahmed Bougacha
8959f2e32f [GlobalISel] Use the same name for all remarks.
While there, switch to the explicit ctor.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296059 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 00:34:47 +00:00
Ahmed Bougacha
abdb8cba99 [GlobalISel] Use the DISubprogram for translation failure remarks.
Justin added support for DISubprogram locs in r295531 and r296052.
Use that instead of no-loc for constants and arguments.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296058 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 00:34:44 +00:00
Ahmed Bougacha
0108464498 [GlobalISel] Remove now-unnecessary variable. NFC.
Since r296047, we're able to return early on failures.
Don't track whether we succeeded.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296057 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 00:34:41 +00:00
Justin Bogner
52ab9f0e65 OptDiag: Summarize the instruction count in asm-printer
Add an optimization remark to asm-printer that summarizes the number
of instructions emitted per function.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296053 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 00:19:22 +00:00
Ahmed Bougacha
d6d9a85ff1 [GlobalISel] Don't translate other blocks when one failed.
We were stopping the translation of the parent block when the
translation of an instruction failed, but we were still trying to
translate the other blocks of the parent function.

Don't do that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296047 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-23 23:57:36 +00:00
Ahmed Bougacha
141a873c65 [GlobalISel] Finalize translated function on scope exit. NFC.
This is the compromise between having a per-function IRTranslator
and manually managing the per-function state.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296046 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-23 23:57:28 +00:00
Kyle Butt
9e601a405e CodeGen: MachineBlockPlacement: Rename member to more general name. NFC.
Rename ComputedTrellisEdges to ComputedEdges to allow for other methods of
pre-computing edges.

Differential Revision: https://reviews.llvm.org/D30308

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296018 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-23 21:22:24 +00:00
Ahmed Bougacha
65d76e1285 [GlobalISel] Emit opt remarks on isel fallbacks.
Having more fine-grained information on the specific construct that
caused us to fallback is valuable for large-scale data collection.

We still have the fallback warning, that's also used for FastISel.
We still need to remove the fallback warning, and teach FastISel to also
emit remarks (it currently has a combination of the warning, stats, and
debug prints: the remarks could unify all three).

The abort-on-fallback path could also be better handled using remarks:
one could imagine a "-Rpass-error", analoguous to "-Werror", which would
promote missed/failed remarks to errors.  It's not clear whether that
would be useful for other remarks though, so we're not there yet.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296013 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-23 21:05:42 +00:00
Ahmed Bougacha
75fdc3a2ae [CodeGen] Teach opt remarks how to print MI instructions.
This will be used with GISel opt remarks.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296012 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-23 21:05:33 +00:00
Ahmed Bougacha
8b200ec55e [CodeGen] Print MI without a newline when skipping debugloc. NFC.
This matches the behavior for skip-operands. While there, document it.
This is a follow-up to r296007.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296011 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-23 21:05:29 +00:00
Stanislav Mekhanoshin
0bf4d71d50 Correct register pressure calculation in presence of subregs
If a subreg is used in an instruction it counts as a whole superreg
for the purpose of register pressure calculation. This patch corrects
improper register pressure calculation by examining operand's lane mask.

Differential Revision: https://reviews.llvm.org/D29835

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296009 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-23 20:19:44 +00:00
Ahmed Bougacha
9628c84c3f [CodeGen] Add a way to SkipDebugLoc in MachineInstr::print(). NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296007 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-23 19:17:31 +00:00
Ahmed Bougacha
33f4d46446 [GlobalISel] Simplify Select type cleanup using a ScopeExit. NFC.
This lets us use more natural early-returns when selection fails.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296006 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-23 19:17:24 +00:00
Sanjay Patel
b41562fd38 [DAG] add convenience function to get -1 constant; NFCI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296004 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-23 19:02:33 +00:00