Commit Graph

1345 Commits

Author SHA1 Message Date
Ulrich Weigand 3f58e45931 Allow matching extend-from-memory with strict FP nodes
This implements a small enhancement to https://reviews.llvm.org/D55506

Specifically, while we were able to match strict FP nodes for
floating-point extend operations with a register as source, this
did not work for operations with memory as source.

That is because from regular operations, this is represented as
a combined "extload" node (which is a variant of a load SD node);
but there is no equivalent using a strict FP operation.

However, it turns out that even in the absence of an extload
node, we can still just match the operations explicitly, e.g.
   (strict_fpextend (f32 (load node:$ptr))

This patch implements that method to match the LDEB/LXEB/LXDB
SystemZ instructions even when the extend uses a strict-FP node.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@364450 91177308-0d34-0410-b5e6-96231b3b80d8
2019-06-26 17:19:12 +00:00
Matt Arsenault a2b05bc24d CodeGen: Introduce a class for registers
Avoids using a plain unsigned for registers throughoug codegen.
Doesn't attempt to change every register use, just something a little
more than the set needed to build after changing the return type of
MachineOperand::getReg().

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@364191 91177308-0d34-0410-b5e6-96231b3b80d8
2019-06-24 15:50:29 +00:00
Ulrich Weigand d3bcee4790 [SystemZ] Support vector load/store alignment hints
Vector load/store instructions support an optional alignment field
that the compiler can use to provide known alignment info to the
hardware.  If the field is used (and the information is correct),
the hardware may be able (on some models) to perform faster memory
accesses than otherwise.

This patch adds support for alignment hints in the assembler and
disassembler, and fills in known alignment during codegen.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@363806 91177308-0d34-0410-b5e6-96231b3b80d8
2019-06-19 14:20:00 +00:00
Jonas Paulsson 066bfdcdb8 [SystemZ] Fix AHIMuxK pseudo expansion.
Do not emit a copy if the source and destination registers are the same.

Review: Ulrich Weigand

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@363665 91177308-0d34-0410-b5e6-96231b3b80d8
2019-06-18 12:10:02 +00:00
Simon Pilgrim 9b95d3f22f [TargetLowering] Add MachineMemOperand::Flags to allowsMemoryAccess tests (PR42123)
As discussed on D62910, we need to check whether particular types of memory access are allowed, not just their alignment/address-space.

This NFC patch adds a MachineMemOperand::Flags argument to allowsMemoryAccess and allowsMisalignedMemoryAccesses, and wires up calls to pass the relevant flags to them.

If people are happy with this approach I can then update X86TargetLowering::allowsMisalignedMemoryAccesses to handle misaligned NT load/stores.

Differential Revision: https://reviews.llvm.org/D63075

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@363179 91177308-0d34-0410-b5e6-96231b3b80d8
2019-06-12 17:14:03 +00:00
Tom Stellard 9f6eb4ee41 Revert CMake: Make most target symbols hidden by default
This reverts r362990 (git commit 374571301dc8e9bc9fdd1d70f86015de198673bd)

This was causing linker warnings on Darwin:

ld: warning: direct access in function 'llvm::initializeEvexToVexInstPassPass(llvm::PassRegistry&)'
from file '../../lib/libLLVMX86CodeGen.a(X86EvexToVex.cpp.o)' to global weak symbol
'void std::__1::__call_once_proxy<std::__1::tuple<void* (&)(llvm::PassRegistry&),
std::__1::reference_wrapper<llvm::PassRegistry>&&> >(void*)' from file '../../lib/libLLVMCore.a(Verifier.cpp.o)'
means the weak symbol cannot be overridden at runtime. This was likely caused by different translation
units being compiled with different visibility settings.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@363028 91177308-0d34-0410-b5e6-96231b3b80d8
2019-06-11 03:21:13 +00:00
Tom Stellard 2cda3f1ac0 CMake: Make most target symbols hidden by default
Summary:
For builds with LLVM_BUILD_LLVM_DYLIB=ON and BUILD_SHARED_LIBS=OFF
this change makes all symbols in the target specific libraries hidden
by default.

A new macro called LLVM_EXTERNAL_VISIBILITY has been added to mark symbols in these
libraries public, which is mainly needed for the definitions of the
LLVMInitialize* functions.

This patch reduces the number of public symbols in libLLVM.so by about
25%.  This should improve load times for the dynamic library and also
make abi checker tools, like abidiff require less memory when analyzing
libLLVM.so

One side-effect of this change is that for builds with
LLVM_BUILD_LLVM_DYLIB=ON and LLVM_LINK_LLVM_DYLIB=ON some unittests that
access symbols that are no longer public will need to be statically linked.

Before and after public symbol counts (using gcc 8.2.1, ld.bfd 2.31.1):
nm before/libLLVM-9svn.so | grep ' [A-Zuvw] ' | wc -l
36221
nm after/libLLVM-9svn.so | grep ' [A-Zuvw] ' | wc -l
26278

Reviewers: chandlerc, beanz, mgorny, rnk, hans

Reviewed By: rnk, hans

Subscribers: Jim, hiraditya, michaelplatings, chapuni, jholewinski, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, javed.absar, sbc100, jgravelle-google, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, mgrang, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, kristina, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D54439

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@362990 91177308-0d34-0410-b5e6-96231b3b80d8
2019-06-10 22:12:56 +00:00
Jonas Paulsson cb48b7a400 [SystemZ] Fix CMakeLists.txt for alphabetical order (NFC).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@362869 91177308-0d34-0410-b5e6-96231b3b80d8
2019-06-08 06:42:02 +00:00
Jonas Paulsson ff136c756d [SystemZ, RegAlloc] Favor 3-address instructions during instruction selection.
This patch aims to reduce spilling and register moves by using the 3-address
versions of instructions per default instead of the 2-address equivalent
ones. It seems that both spilling and register moves are improved noticeably
generally.

Regalloc hints are passed to increase conversions to 2-address instructions
which are done in SystemZShortenInst.cpp (after regalloc).

Since the SystemZ reg/mem instructions are 2-address (dst and lhs regs are
the same), foldMemoryOperandImpl() can no longer trivially fold a spilled
source register since the reg/reg instruction is now 3-address. In order to
remedy this, new 3-address pseudo memory instructions are used to perform the
folding only when the dst and lhs virtual registers are known to be allocated
to the same physreg. In order to not let MachineCopyPropagation run and
change registers on these transformed instructions (making it 3-address), a
new target pass called SystemZPostRewrite.cpp is run just after
VirtRegRewriter, that immediately lowers the pseudo to a target instruction.

If it would have been possibe to insert a COPY instruction and change a
register operand (convert to 2-address) in foldMemoryOperandImpl() while
trusting that the caller (e.g. InlineSpiller) would update/repair the
involved LiveIntervals, the solution involving pseudo instructions would not
have been needed. This is perhaps a potential improvement (see Phabricator
post).

Common code changes:

* A new hook TargetPassConfig::addPostRewrite() is utilized to be able to run a
target pass immediately before MachineCopyPropagation.

* VirtRegMap is passed as an argument to foldMemoryOperand().

Review: Ulrich Weigand, Quentin Colombet
https://reviews.llvm.org/D60888

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@362868 91177308-0d34-0410-b5e6-96231b3b80d8
2019-06-08 06:19:15 +00:00
Ulrich Weigand ef54162998 Allow target to handle STRICT floating-point nodes
The ISD::STRICT_ nodes used to implement the constrained floating-point
intrinsics are currently never passed to the target back-end, which makes
it impossible to handle them correctly (e.g. mark instructions are depending
on a floating-point status and control register, or mark instructions as
possibly trapping).

This patch allows the target to use setOperationAction to switch the action
on ISD::STRICT_ nodes to Legal. If this is done, the SelectionDAG common code
will stop converting the STRICT nodes to regular floating-point nodes, but
instead pass the STRICT nodes to the target using normal SelectionDAG
matching rules.

To avoid having the back-end duplicate all the floating-point instruction
patterns to handle both strict and non-strict variants, we make the MI
codegen explicitly aware of the floating-point exceptions by introducing
two new concepts:

- A new MCID flag "mayRaiseFPException" that the target should set on any
  instruction that possibly can raise FP exception according to the
  architecture definition.
- A new MI flag FPExcept that CodeGen/SelectionDAG will set on any MI
  instruction resulting from expansion of any constrained FP intrinsic.

Any MI instruction that is *both* marked as mayRaiseFPException *and*
FPExcept then needs to be considered as raising exceptions by MI-level
codegen (e.g. scheduling).

Setting those two new flags is straightforward. The mayRaiseFPException
flag is simply set via TableGen by marking all relevant instruction
patterns in the .td files.

The FPExcept flag is set in SDNodeFlags when creating the STRICT_ nodes
in the SelectionDAG, and gets inherited in the MachineSDNode nodes created
from it during instruction selection. The flag is then transfered to an
MIFlag when creating the MI from the MachineSDNode. This is handled just
like fast-math flags like no-nans are handled today.

This patch includes both common code changes required to implement the
new features, and the SystemZ implementation.

Reviewed By: andrew.w.kaylor

Differential Revision: https://reviews.llvm.org/D55506



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@362663 91177308-0d34-0410-b5e6-96231b3b80d8
2019-06-05 22:33:10 +00:00
Sjoerd Meijer b4e0516439 [TargetMachine] error message unsupported code model
When the tiny code model is requested for a target machine that does not
support this, we get an error message (which is nice) but also this diagnostic
and request to submit a bug report:

    fatal error: error in backend: Target does not support the tiny CodeModel
    [Inferior 2 (process 31509) exited with code 0106]
    clang-9: error: clang frontend command failed with exit code 70 (use -v to see invocation)
    (gdb) clang version 9.0.0 (http://llvm.org/git/clang.git 29994b0c63a40f9c97c664170244a7bba5ecc15e) (http://llvm.org/git/llvm.git 95606fdf91c2d63a931e865f4b78b2e9828ddc74)
    Target: arm-arm-none-eabi
    Thread model: posix
    clang-9: note: diagnostic msg: PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace, preprocessed source, and associated run script.
    clang-9: note: diagnostic msg:
    ********************
    PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
    Preprocessed source(s) and associated run script(s) are located at:
    clang-9: note: diagnostic msg: /tmp/tiny-dfe1a2.c
    clang-9: note: diagnostic msg: /tmp/tiny-dfe1a2.sh
    clang-9: note: diagnostic msg:

But this is not a bug, this is a feature. :-) Not only is this not a bug, this
is also pretty confusing. This patch causes just to print the fatal error and
not the diagnostic:

fatal error: error in backend: Target does not support the tiny CodeModel

Differential Revision: https://reviews.llvm.org/D62236


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@361370 91177308-0d34-0410-b5e6-96231b3b80d8
2019-05-22 10:40:26 +00:00
Jonas Paulsson 71efe3e09f [SystemZ] Bugfix in SystemZTargetLowering::combineIntDIVREM()
Make sure to not unroll a vector division/remainder (with a constant splat
divisor) after type legalization, since the scalar type may then be illegal.

Review: Ulrich Weigand
https://reviews.llvm.org/D62036

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360965 91177308-0d34-0410-b5e6-96231b3b80d8
2019-05-17 00:50:35 +00:00
Richard Trieu ca462efaa8 [SystemZ] Create a TargetInfo header. NFC
Move the declarations of getThe<Name>Target() functions into a new header in
TargetInfo and make users of these functions include this new header.
This fixes a layering problem.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360734 91177308-0d34-0410-b5e6-96231b3b80d8
2019-05-15 00:46:18 +00:00
Ulrich Weigand 12d462cd1b [SystemZ] Model floating-point control register
This adds the FPC (floating-point control register) as a reserved
physical register and models its use by SystemZ instructions.

Note that only the current rounding modes and the IEEE exception
masks are modeled.  *Changes* of the FPC due to exceptions (in
particular the IEEE exception flags and the DXC) are not modeled.

At this point, this patch is mostly NFC, but it will prevent
scheduling of floating-point instructions across SPFC/LFPC etc.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360570 91177308-0d34-0410-b5e6-96231b3b80d8
2019-05-13 09:47:26 +00:00
Richard Trieu 0467a2191c [SystemZ] Move InstPrinter files to MCTargetDesc. NFC
For some targets, there is a circular dependency between InstPrinter and
MCTargetDesc.  Merging them together will fix this.  For the other targets,
the merging is to maintain consistency so all targets will have the same
structure.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360510 91177308-0d34-0410-b5e6-96231b3b80d8
2019-05-11 03:36:16 +00:00
Simon Pilgrim 0937a0dc77 Remove superfluous break from switch statement. NFCI.
Reported in https://www.viva64.com/en/b/0629/

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@359467 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-29 16:45:35 +00:00
Nick Desaulniers b3cb8ab451 [AsmPrinter] refactor to support %c w/ GlobalAddress'
Summary:
Targets like ARM, MSP430, PPC, and SystemZ have complex behavior when
printing the address of a MachineOperand::MO_GlobalAddress. Move that
handling into a new overriden method in each base class. A virtual
method was added to the base class for handling the generic case.

Refactors a few subclasses to support the target independent %a, %c, and
%n.

The patch also contains small cleanups for AVRAsmPrinter and
SystemZAsmPrinter.

It seems that NVPTXTargetLowering is possibly missing some logic to
transform GlobalAddressSDNodes for
TargetLowering::LowerAsmOperandForConstraint to handle with "i" extended
inline assembly asm constraints.

Fixes:
- https://bugs.llvm.org/show_bug.cgi?id=41402
- https://github.com/ClangBuiltLinux/linux/issues/449

Reviewers: echristo, void

Reviewed By: void

Subscribers: void, craig.topper, jholewinski, dschuff, jyknight, dylanmckay, sdardis, nemanjai, javed.absar, sbc100, jgravelle-google, eraman, kristof.beyls, hiraditya, aheejin, kbarton, fedor.sergeev, jrtc27, atanasyan, jsji, llvm-commits, kees, tpimh, nathanchance, peter.smith, srhines

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60887

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@359337 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-26 18:45:04 +00:00
Bjorn Pettersson bba2202bb1 [CodeGen] Add "const" to MachineInstr::mayAlias
Summary:
The basic idea here is to make it possible to use
MachineInstr::mayAlias also when the MachineInstr
is const (or the "Other" MachineInstr is const).

The addition of const in MachineInstr::mayAlias
then rippled down to the need for adding const
in several other places, such as
TargetTransformInfo::getMemOperandWithOffset.

Reviewers: hfinkel

Reviewed By: hfinkel

Subscribers: hfinkel, MatzeB, arsenm, jvesely, nhaehnle, hiraditya, javed.absar, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60856

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358744 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-19 09:08:38 +00:00
Eric Christopher d46ddf0061 Add explicit dependencies on MCSection.h and MCDwarf.h to the .cpp
files rather than rely on transitive includes from MCStreamer.h.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358263 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-12 07:40:01 +00:00
Nick Desaulniers a943056482 [AsmPrinter] refactor to remove remove AsmVariant. NFC
Summary:
The InlineAsm::AsmDialect is only required for X86; no architecture
makes use of it and as such it gets passed around between arch-specific
and general code while being unused for all architectures but X86.

Since the AsmDialect is queried from a MachineInstr, which we also pass
around, remove the additional AsmDialect parameter and query for it deep
in the X86AsmPrinter only when needed/as late as possible.

This refactor should help later planned refactors to AsmPrinter, as this
difference in the X86AsmPrinter makes it harder to make AsmPrinter more
generic.

Reviewers: craig.topper

Subscribers: jholewinski, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, javed.absar, sbc100, jgravelle-google, eraman, hiraditya, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, llvm-commits, peter.smith, srhines

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60488

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358101 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-10 16:38:43 +00:00
Jonas Paulsson 8d88d919bb [SystemZ] Bugfix in isFusableLoadOpStorePattern()
This function is responsible for checking the legality of fusing an instance
of load -> op -> store into a single operation. In the SystemZ backend the
check was incomplete and a test case emerged with a cycle in the instruction
selection DAG as a result.

Instead of using the NodeIds to determine node relationships,
hasPredecessorHelper() now is used just like in the X86 backend. This handled
the failing tests and as well gave a few additional transformations on
benchmarks.

The SystemZ isFusableLoadOpStorePattern() is now a very near copy of the X86
function, and it seems this could be made a utility function in common code
instead.

Review: Ulrich Weigand
https://reviews.llvm.org/D60255

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@357688 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-04 12:12:35 +00:00
Ulrich Weigand 909ca0c8af [SystemZ] Improve codegen for certain SADDO-immediate cases
When performing an add-with-overflow with an immediate in the
range -2G ... -4G, code currently loads the immediate into a
register, which generally takes two instructions.

In this particular case, it is preferable to load the negated
immediate into a register instead, which always only requires
one instruction, and then perform a subtract.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@357597 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-03 15:09:19 +00:00
Jonas Paulsson 1d777c335f [SystemZ] Improve instruction selection of 64 bit shifts and rotates.
For shift and rotate instructions that only use the last 6 bits of the shift
amount, a shift amount of (x*64-s) can be substituted with (-s). This saves
one instruction and a register:

  lhi     %r1, 64
  sr      %r1, %r3
  sllg    %r2, %r2, 0(%r1)
  =>
  lcr     %r1, %r3
  sllg    %r2, %r2, 0(%r1)

Review: Ulrich Weigand

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@357481 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-02 15:36:30 +00:00
Jonas Paulsson 6919cecfc3 [SystemZ] Remove LRMux pseudo instruction.
This instruction is unused and not needed.

Review: Ulrich Weigand.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356997 91177308-0d34-0410-b5e6-96231b3b80d8
2019-03-26 15:13:48 +00:00
Adhemerval Zanella 0ce3660e40 [TargetLowering] Add code size information on isFPImmLegal. NFC
This allows better code size for aarch64 floating point materialization
in a future patch.

Reviewers: evandro

Differential Revision: https://reviews.llvm.org/D58690



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356389 91177308-0d34-0410-b5e6-96231b3b80d8
2019-03-18 18:40:07 +00:00
Stanislav Mekhanoshin 5d5019bab2 Use bitset for assembler predicates
AMDGPU target run out of Subtarget feature flags hitting the limit of 64.
AssemblerPredicates uses at most uint64_t for their representation.
At the same time CodeGen has exhausted this a long time ago and switched
to a FeatureBitset with the current limit of 192 bits.

This patch completes transition to the bitset for feature bits extending
it to asm matcher and MC code emitter.

Differential Revision: https://reviews.llvm.org/D59002

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@355839 91177308-0d34-0410-b5e6-96231b3b80d8
2019-03-11 17:04:35 +00:00
Craig Topper 7f415404f7 Recommit r355224 "[TableGen][SelectionDAG][X86] Add specific isel matchers for immAllZerosV/immAllOnesV. Remove bitcasts from X86 patterns that are no longer necessary."
Includes a fix to emit a CheckOpcode for build_vector when immAllZerosV/immAllOnesV is used as a pattern root. This means it can't be used to look through bitcasts when used as a root, but that's probably ok. This extra CheckOpcode will ensure that the first match in the isel table will be a SwitchOpcode which is needed by the caching optimization in the ISel Matcher.

Original commit message:

Previously we had build_vector PatFrags that called ISD::isBuildVectorAllZeros/Ones. Internally the ISD::isBuildVectorAllZeros/Ones look through bitcasts, but we aren't able to take advantage of that in isel. Instead of we have to canonicalize the types of the all zeros/ones build_vectors and insert bitcasts. Then we have to pattern match those exact bitcasts.

By emitting specific matchers for these 2 nodes, we can make isel look through any bitcasts without needing to explicitly match them. We should also be able to remove the canonicalization to vXi32 from lowering, but I've left that for a follow up.

This removes something like 40,000 bytes from the X86 isel table.

Differential Revision: https://reviews.llvm.org/D58595

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@355784 91177308-0d34-0410-b5e6-96231b3b80d8
2019-03-10 05:21:52 +00:00
Craig Topper ac1eef5551 Revert r355224 "[TableGen][SelectionDAG][X86] Add specific isel matchers for immAllZerosV/immAllOnesV. Remove bitcasts from X86 patterns that are no longer necessary."
This caused the first matcher in the isel table for many targets to Opc_Scope instead of Opc_SwitchOpcode. This leads to a significant increase in isel match failures.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@355433 91177308-0d34-0410-b5e6-96231b3b80d8
2019-03-05 19:18:16 +00:00
Craig Topper a3fccdcc5d [TableGen][SelectionDAG][X86] Add specific isel matchers for immAllZerosV/immAllOnesV. Remove bitcasts from X86 patterns that are no longer necessary.
Previously we had build_vector PatFrags that called ISD::isBuildVectorAllZeros/Ones. Internally the ISD::isBuildVectorAllZeros/Ones look through bitcasts, but we aren't able to take advantage of that in isel. Instead of we have to canonicalize the types of the all zeros/ones build_vectors and insert bitcasts. Then we have to pattern match those exact bitcasts.

By emitting specific matchers for these 2 nodes, we can make isel look through any bitcasts without needing to explicitly match them. We should also be able to remove the canonicalization to vXi32 from lowering, but I've left that for a follow up.

This removes something like 40,000 bytes from the X86 isel table.

Differential Revision: https://reviews.llvm.org/D58595

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@355224 91177308-0d34-0410-b5e6-96231b3b80d8
2019-03-01 20:18:38 +00:00
Bjorn Pettersson 85de1fd399 Add support for computing "zext of value" in KnownBits. NFCI
Summary:
The description of KnownBits::zext() and
KnownBits::zextOrTrunc() has confusingly been telling
that the operation is equivalent to zero extending the
value we're tracking. That has not been true, instead
the user has been forced to explicitly set the extended
bits as known zero afterwards.

This patch adds a second argument to KnownBits::zext()
and KnownBits::zextOrTrunc() to control if the extended
bits should be considered as known zero or as unknown.

Reviewers: craig.topper, RKSimon

Reviewed By: RKSimon

Subscribers: javed.absar, hiraditya, jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58650

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@355099 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-28 15:45:29 +00:00
Philip Reames 9faff7e6c7 Seperate volatility and atomicity/ordering in SelectionDAG
At the moment, we mark every atomic memory access as being also volatile. This is unnecessarily conservative and prohibits many legal transforms (DCE, folding, etc..).

This patch removes MOVolatile from the MachineMemOperands of atomic, but not volatile, instructions. This should be strictly NFC after a series of previous patches which have gone in to ensure backend code is conservative about handling of isAtomic MMOs. Once it's in and baked for a bit, we'll start working through removing unnecessary bailouts one by one. We applied this same strategy to the middle end a few years ago, with good success.

To make sure this patch itself is NFC, it is build on top of a series of other patches which adjust code to (for the moment) be as conservative for an atomic access as for a volatile access and build up a test corpus (mostly in test/CodeGen/X86/atomics-unordered.ll)..

Previously landed

    D57593 Fix a bug in the definition of isUnordered on MachineMemOperand
    D57596 [CodeGen] Be conservative about atomic accesses as for volatile
    D57802 Be conservative about unordered accesses for the moment
    rL353959: [Tests] First batch of cornercase tests for unordered atomics.
    rL353966: [Tests] RMW folding tests w/unordered atomic operations.
    rL353972: [Tests] More unordered atomic lowering tests.
    rL353989: [SelectionDAG] Inline a single use helper function, and remove last non-MMO interface
    rL354740: [Hexagon, SystemZ] Be super conservative about atomics
    rL354800: [Lanai] Be super conservative about atomics
    rL354845: [ARM] Be super conservative about atomics

Attention Out of Tree Backend Owners: This patch may break you. If it does, you can use the TLI getMMOFlags hook to restore the MOVolatile to any instruction you need to. (See llvm-dev thread titled "PSA: Changes to how atomics are handled in backends" started Feb 27, 2019.)

Differential Revision: https://reviews.llvm.org/D57601



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@355025 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-27 20:20:08 +00:00
Jonas Paulsson 96e27952a5 [SystemZ] Pass regalloc hints to help Load-and-Test transformations.
Since there is no "Load-and-Test-High" instruction, the 32 bit load of a
register to be compared with 0 can only be implemented with LT if the virtual
GRX32 register ends up in a low part (GR32 register).

This patch detects these cases and passes the GR32 registers (low parts) as
(soft) hints in getRegAllocationHints().

Review: Ulrich Weigand.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@354935 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-27 00:18:28 +00:00
Jonas Paulsson 78b72added [SystemZ] Wait with selection of legal vector/FP constants until Select().
This patch aims to make sure that any such constant that can be generated
with a vector instruction (for example VGBM) is recognized as such during
legalization and kept as a target independent node through post-legalize
DAGCombining.

Two new functions named isVectorConstantLegal() and loadVectorConstant()
replace old ways of handling vector/FP constants.

A new struct named SystemZVectorConstantInfo is used to cache the results of
isVectorConstantLegal() and pass them onto loadVectorConstant().

Support for fp128 constants in the presence of FeatureVectorEnhancements1
(z14) has been added.

Review: Ulrich Weigand
https://reviews.llvm.org/D58270

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@354896 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-26 16:47:59 +00:00
Philip Reames 89625a62f2 [Hexagon, SystemZ] Be super conservative about atomics
As requested during review of D57601, be equally conservative for atomic MMOs as for volatile MMOs in all in tree backends. At the moment, all atomic MMOs are also volatile, but I'm about to change that.

Reviewed as part of https://reviews.llvm.org/D58490, with other backends still pending review.  



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@354740 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-24 00:45:09 +00:00
Jonas Paulsson 9129f92efa Recommit "[SystemZ] Do not emit VEXTEND or VROUND nodes without vector support."
It seems there were some problem with using a .mir test. For some reason
doing '-stop-before=codegenprepare' and then '-start-before=codegenprepare'
on the output .mir file results in the NoVRegs Property after instruction
selection.

Recommitting the same test as an .ll file instead.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@354160 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-15 19:13:55 +00:00
Francis Visoiu Mistrih 5716349e30 Revert "[SystemZ] Do not emit VEXTEND or VROUND nodes without vector support."
This reverts commit aa0b77d3395dc6ab91647138139c1a15a3aa088d.

This fails to pass the machine verifier:
http://green.lab.llvm.org/green/job/clang-stage1-cmake-RA-expensive/13579/

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@354096 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-15 03:01:09 +00:00
Jonas Paulsson 05fc6965d5 [SystemZ] Do not emit VEXTEND or VROUND nodes without vector support.
Review: Ulrich Weigand
https://reviews.llvm.org/D58240

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@354039 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-14 17:58:48 +00:00
Jonas Paulsson 17f2e5bd11 [SystemZ] Remember to cast value to void to disable warning.
Hopefully fixes buildbot problems.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353898 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-12 23:13:18 +00:00
Jonas Paulsson 3044368de2 [SystemZ] Use VGM whenever possible to load FP immediates.
isFPImmLegal() has been extended to recognize certain FP immediates that can
be built with VGM (Vector Generate Mask).

These scalar FP immediates (that were previously loaded from the constant
pool) are now selected as VGMF/VGMG in Select().

Review: Ulrich Weigand
https://reviews.llvm.org/D58003

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353867 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-12 18:06:06 +00:00
Jonas Paulsson 0e5a502581 [SystemZ] Improved handling of the @llvm.ctlz intrinsic.
Since SystemZ supports counting of leading zeros with the FLOGR instruction,
isCheapToSpeculateCtlz() should return true, which it now does.

ISD::CTLZ_ZERO_UNDEF i32 is now handled the same way as ISD::CTLZ is, which
is needed since promotion to i64 is required and CTLZ_ZERO_UNDEF is only
expanded to CTLZ if it is Legal or Custom.

Review: Ulrich Weigand
https://reviews.llvm.org/D57710

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353330 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-06 19:23:31 +00:00
Jonas Paulsson 954d6be705 [SystemZ] Wait with VGBM selection until after DAGCombine2.
Don't lower BUILD_VECTORs to BYTE_MASK, but instead expose the BUILD_VECTORs
to the DAGCombiner and select them to VGBM in Select(). This allows the
DAGCombiner to understand the constant vector values.

For floating point, only all-zeros vectors are now generated with VGBM, as it
turned out to be somewhat complicated to handle any arbitrary constants,
while in practice this is very rare and hardly needed.

The SystemZ ISD opcodes z_byte_mask, z_vzero and z_vones have been removed.

Review: Ulrich Weigand
https://reviews.llvm.org/D57152

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353325 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-06 18:59:19 +00:00
Ulrich Weigand 44f220f910 [SystemZ] Do not return INT_MIN from strcmp/memcmp
The IPM sequence currently generated to compute the strcmp/memcmp
result will return INT_MIN for the "less than zero" case.  While
this is in compliance with the standard, strictly speaking, it
turns out that common applications cannot handle this, e.g. because
they negate a comparison result in order to implement reverse
compares.

This patch changes code to use a different sequence that will result
in -2 for the "less than zero" case (same as GCC).  However, this
requires that the two source operands of the compare instructions
are inverted, which breaks the optimization in removeIPMBasedCompare.
Therefore, I've removed this (and all of optimizeCompareInstr), and
replaced it with a mostly equivalent optimization in combineCCMask
at the DAGcombine level.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353304 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-06 15:10:13 +00:00
Craig Topper 7ef4c67822 [CodeGen][ARC][SystemZ][WebAssembly] Use MachineInstr::isInlineAsm in more places instead of just comparing opcode. NFCI
I'm looking at adding a second INLINEASM opcode for better modeling asm-goto
as a terminator. Using the existing predicate will reduce teh number of
places that will need to use the new opcode.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353095 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-04 21:24:13 +00:00
James Y Knight 6029aa8149 [opaque pointer types] Pass function types to CallInst creation.
This cleans up all CallInst creation in LLVM to explicitly pass a
function type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57170

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@352909 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-01 20:43:25 +00:00
Nirav Dave f3a785f249 [DAG][SystemZ] Define unwrapAddress for PCREL_WRAPPER.
Summary:
Like with X86, this allows better DAG-level alias analysis and
alignment inference for wrapped addresses.

Reviewers: jonpa, uweigand

Reviewed By: uweigand

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D57407

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@352786 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-31 19:58:34 +00:00
Jonas Paulsson 1ca3aae406 [SystemZ] Remember to reset the NoPHIs property on MF in createPHIsForSelects()
After creating new PHI instructions during isel pseudo expansion, the NoPHIs
property of MF should be reset in case it was previously set.

Review: Ulrich Weigand

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@352030 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-24 07:54:41 +00:00
Jonas Paulsson 842b69bf63 [SystemZ] Handle DBG_VALUE instructions in two places in backend.
Two backend optimizations failed to handle cases when compiled with -g, due
to failing to consider DBG_VALUE instructions. This was in
SystemZTargetLowering::emitSelect() and
SystemZElimCompare::getRegReferences().

This patch makes sure that DBG_VALUEs are recognized so that they do not
affect these optimizations.

Tests for branch-on-count, load-and-trap and consecutive selects.

Review: Ulrich Weigand
https://reviews.llvm.org/D57048

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351928 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-23 07:42:26 +00:00
Chandler Carruth 6b547686c5 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351636 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-19 08:50:56 +00:00
Simon Pilgrim 44ddf8fbce [SystemZ] Always use the version of computeKnownBits that returns a value. NFCI.
Continues the work started by @bogner in rL340594 to remove uses of the KnownBits output paramater version.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349906 91177308-0d34-0410-b5e6-96231b3b80d8
2018-12-21 14:50:54 +00:00
Ulrich Weigand a564872860 [SystemZ] "Generic" vector assembler instructions shoud clobber CC
There are several vector instructions which may or may not set the
condition code register, depending on the value of an argument.

For codegen, we use two versions of the instruction, one that sets
CC and one that doesn't, which hard-code appropriate values of that
argument.  But we also have a "generic" version of the instruction
that is used for the assembler/disassembler.  These generic versions
should always be considered to clobber CC just to be safe.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349761 91177308-0d34-0410-b5e6-96231b3b80d8
2018-12-20 14:24:17 +00:00