Commit Graph

1450 Commits

Author SHA1 Message Date
Fangrui Song 774971030d [MCStreamer] De-capitalize EmitValue EmitIntValue{,InHex} 2020-02-14 23:08:40 -08:00
Fangrui Song 6d2d589b06 [MC] De-capitalize another set of MCStreamer::Emit* functions
Emit{ValueTo,Code}Alignment Emit{DTP,TP,GP}* EmitSymbolValue etc
2020-02-14 19:26:52 -08:00
Fangrui Song bcd24b2d43 [AsmPrinter][MCStreamer] De-capitalize EmitInstruction and EmitCFI* 2020-02-13 22:08:55 -08:00
Fangrui Song 1d49eb00d9 [AsmPrinter] De-capitalize all AsmPrinter::Emit* but EmitInstruction
Similar to rL328848.
2020-02-13 17:06:24 -08:00
Fangrui Song 0dce409cee [AsmPrinter] De-capitalize Emit{Function,BasicBlock]* and Emit{Start,End}OfAsmFile 2020-02-13 13:22:49 -08:00
Jay Foad 32aac25637 [KnownBits] Introduce anyext instead of passing a flag into zext
Summary:
This was a very odd API, where you had to pass a flag into a zext
function to say whether the extended bits really were zero or not. All
callers passed in a literal true or false.

I think it's much clearer to make the function name reflect the
operation being performed on the value we're tracking (rather than on
the KnownBits Zero and One fields), so zext means the value is being
zero extended and new function anyext means the value is being extended
with unknown bits.

NFC.

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74482
2020-02-12 19:06:53 +00:00
Eric Astor 8d5bf0422b [ms] [llvm-ml] Add support for attempted register parsing
Summary:
Add a new method (tryParseRegister) that attempts to parse a register specification.

MASM allows the use of IFDEF <register>, as well as IFDEF <symbol>. To accommodate this, we make it possible to check whether a register specification can be parsed at the current location, without failing the entire parse if it can't.

Reviewers: thakis

Reviewed By: thakis

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73486
2020-02-11 10:45:33 -05:00
Jonas Paulsson 0311e28e9c [SystemZ] Bugfix in emitSelect()
When more than one SelectPseudo instruction is handled a new MBB is
returned. This must not be done if that would result in leaving an undhandled
isel pseudo behind in the original MBB.

Fixes https://bugs.llvm.org/show_bug.cgi?id=44849.

Review: Ulrich Weigand

Differential Revision: https://reviews.llvm.org/D74352
2020-02-11 10:41:01 -05:00
Jonas Paulsson fcdb99e0b5 [SystemZ] Add a subtarget cache like some other targets already have.
Each function is with this compiled with the SystemZSubtarget initialized
from the functions attributes.

Review: Ulrich Weigand.

Differential Revision: https://reviews.llvm.org/D74086
2020-02-10 13:10:58 -05:00
Kai Nacke 34946dfd79 [SystemZ] Add implementation for the intrinsic llvm.read_register
This change implements the llvm intrinsic llvm.read_register for
the SystemZ platform which returns the value of the specified
register
(http://llvm.org/docs/LangRef.html#llvm-read-register-and-llvm-write-register-intrinsics).
This implementation returns the value of the stack register, and
can be extended to return the value of other registers. The
implementation for this intrinsic exists on various other platforms
including Power, x86, ARM, etc. but missing on SystemZ.

Reviewers: uweigand

Differential Revision: https://reviews.llvm.org/D73378
2020-02-10 08:19:10 -05:00
Kai Nacke a5040d5ec9 [SytemZ] Disable vector ABI when using option -march=arch[8|9|10]
When specifying -march=arch[8|9|10], those CPU types do NOT support
the vector extension. In this case the vector ABI must be disabled.
The generated data layout should NOT contain 64-v128.

Reviewers: uweigand

Differential Revision: https://reviews.llvm.org/D74146
2020-02-10 04:14:05 -05:00
Benjamin Kramer e4230a9f6c ArrayRef'ize spillCalleeSavedRegisters. NFCI. 2020-02-08 12:19:23 +01:00
Jonas Paulsson 4a3760d2ba [SystemZ] Improve handling of inline asm constraints.
The "{=v0}" constraint did not result in the expected error message in the
abscence of the vector facility, because 'v0' matches as a string into the
AnyRegBitRegClass in common code.

This patch adds checks for vector support in case of "{v" and soft-float in
case of "{f" to remedy this.

Review: Ulrich Weigand.
2020-02-05 17:04:16 -05:00
Jonas Paulsson 563e84790f [SystemZ] Support -msoft-float
This is needed when building the Linux kernel.

Review: Ulrich Weigand

Differential Revision: https://reviews.llvm.org/D72189
2020-02-04 10:32:45 -05:00
Guillaume Chatelet 333f2ad8b8 [Alignment][NFC] Use Align for getMemcpy/Memmove/Memset
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: arsenm, dschuff, jyknight, sdardis, nemanjai, jvesely, nhaehnle, sbc100, jgravelle-google, hiraditya, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73885
2020-02-03 17:13:19 +01:00
Simon Moll 5c8ba508b2 [NFC] unsigned->Register in storeRegTo/loadRegFromStack
Summary:
This patch makes progress on the 'unsigned -> Register' rewrite for
`TargetInstrInfo::loadRegFromStack` and `TII::storeRegToStack`.

Reviewers: arsenm, craig.topper, uweigand, jpienaar, atanasyan, venkatra, robertlytton, dylanmckay, t.p.northover, kparzysz, tstellar, k-ishizaka

Reviewed By: arsenm

Subscribers: wuzish, merge_guards_bot, jyknight, sdardis, nemanjai, jvesely, wdng, nhaehnle, hiraditya, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73870
2020-02-03 14:22:16 +01:00
Benjamin Kramer adcd026838 Make llvm::StringRef to std::string conversions explicit.
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.

This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.

This doesn't actually modify StringRef yet, I'll do that in a follow-up.
2020-01-28 23:25:25 +01:00
Amara Emerson 67a8775322 [AArch64] Don't generate gpr CSEL instructions in early-ifcvt if regclasses aren't compatible.
In GlobalISel we may in some unfortunate circumstances generate PHIs with
operands that are on separate banks. If-conversion doesn't currently check for
that case and ends up generating a CSEL on AArch64 with incorrect register
operands.

Differential Revision: https://reviews.llvm.org/D72961
2020-01-21 16:51:31 -08:00
Fangrui Song 8e8a75ad50 [TargetRegisterInfo] Default trackLivenessAfterRegAlloc() to true
Except AMDGPU/R600RegisterInfo (a bunch of MIR tests seem to have
problems), every target overrides it with true. PostMachineScheduler
requires livein information. Not providing it can cause assertion
failures in ScheduleDAGInstrs::addSchedBarrierDeps().
2020-01-19 14:20:37 -08:00
Matt Arsenault 0d0fce42b0 GlobalISel: Preserve load/store metadata in IRTranslator
This was dropping the invariant metadata on dead argument loads, so
they weren't deleted.

Atomics still need to be fixed the same way. Also, apparently store
was never preserving dereferencable which should also be fixed.
2020-01-16 13:49:43 -05:00
Tom Stellard 0dbcb36394 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: merge_guards_bot, luismarques, smeenai, ldionne, lenary, s.egerton, pzheng, sameer.abuasal, MaskRay, wuzish, echristo, Jim, hiraditya, michaelplatings, chapuni, jholewinski, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, 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
2020-01-14 19:46:52 -08:00
Fangrui Song 6fdd6a7b3f [Disassembler] Delete the VStream parameter of MCDisassembler::getInstruction()
The argument is llvm::null() everywhere except llvm::errs() in
llvm-objdump in -DLLVM_ENABLE_ASSERTIONS=On builds. It is used by no
target but X86 in -DLLVM_ENABLE_ASSERTIONS=On builds.

If we ever have the needs to add verbose log to disassemblers, we can
record log with a member function, instead of passing it around as an
argument.
2020-01-11 13:34:52 -08:00
Ulrich Weigand f0fd11df7d [FPEnv] Invert sense of MIFlag::FPExcept flag
In D71841 we inverted the sense of the SDNode-level flag to ensure all nodes
default to potentially raising FP exceptions unless otherwise specified --
i.e. if we forget to propagate the flag somewhere, the effect is now only
lost performance, not incorrect code.

However, the related flag at the MI level still defaults to nodes not raising
FP exceptions unless otherwise specified. To be fully on the (conservatively)
safe side, we should invert that flag as well.

This patch does so by replacing MIFlag::FPExcept with MIFlag::NoFPExcept.
(Note that this does also introduce an incompatible change in the MIR format.)

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D72466
2020-01-10 15:34:50 +01:00
Ulrich Weigand b51fa8670f [SystemZ] Fix matching another pattern for nxgrk (PR44496)
SystemZDAGToDAGISel::Select will attempt to split logical instruction
with a large immediate constant.  This must not happen if the result
matches one of the z15 combined operations, so the code checks for
those.  However, one of them was missed, causing invalid code to
be generated in the test case for PR44496.
2020-01-09 19:06:22 +01:00
Fangrui Song 3d87d0b925 [MC] Add parameter `Address` to MCInstrPrinter::printInstruction
Follow-up of D72172.

Reviewed By: jhenderson, rnk

Differential Revision: https://reviews.llvm.org/D72180
2020-01-06 20:44:14 -08:00
Fangrui Song aa708763d3 [MC] Add parameter `Address` to MCInstPrinter::printInst
printInst prints a branch/call instruction as `b offset` (there are many
variants on various targets) instead of `b address`.

It is a convention to use address instead of offset in most external
symbolizers/disassemblers. This difference makes `llvm-objdump -d`
output unsatisfactory.

Add `uint64_t Address` to printInst(), so that it can pass the argument to
printInstruction(). `raw_ostream &OS` is moved to the last to be
consistent with other print* methods.

The next step is to pass `Address` to printInstruction() (generated by
tablegen from the instruction set description). We can gradually migrate
targets to print addresses instead of offsets.

In any case, downstream projects which don't know `Address` can pass 0 as
the argument.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D72172
2020-01-06 20:42:22 -08:00
Jonas Paulsson c0f1eac008 [SystemZ] Don't allow CL option -mpacked-stack with -mbackchain.
-mpacked-stack is currently not supported with -mbackchain, so this should
result in a compilation error message instead of being silently ignored.

Review: Ulrich Weigand
2020-01-03 12:26:54 -08:00
Jonas Paulsson 982695c069 [SystemZ] Create brcl 0,0 instead of brcl 0,3 in EmitNop for 6 bytes.
For consistency with GCC, the target label is moved to the brcl itself
instead of the next instruction.

Review: Ulrich Weigand
2020-01-02 13:21:04 -08:00
Ulrich Weigand 63336795f0 [FPEnv] Default NoFPExcept SDNodeFlag to false
The NoFPExcept bit in SDNodeFlags currently defaults to true, unlike all
other such flags. This is a problem, because it implies that all code that
transforms SDNodes without copying flags can introduce a correctness bug,
not just a missed optimization.

This patch changes the default to false. This makes it necessary to move
setting the (No)FPExcept flag for constrained intrinsics from the
visitConstrainedIntrinsic routine to the generic visit routine at the
place where the other flags are set, or else the intersectFlagsWith
call would erase the NoFPExcept flag again.

In order to avoid making non-strict FP code worse, whenever
SelectionDAGISel::SelectCodeCommon matches on a set of orignal nodes
none of which can raise FP exceptions, it will preserve this property
on all results nodes generated, by setting the NoFPExcept flag on
those result nodes that would otherwise be considered as raising
an FP exception.

To check whether or not an SD node should be considered as raising
an FP exception, the following logic applies:

- For machine nodes, check the mayRaiseFPException property of
  the underlying MI instruction
- For regular nodes, check isStrictFPOpcode
- For target nodes, check a newly introduced isTargetStrictFPOpcode

The latter is implemented by reserving a range of target opcodes,
similarly to how memory opcodes are identified. (Note that there a
bit of a quirk in identifying target nodes that are both memory nodes
and strict FP nodes. To simplify the logic, right now all target memory
nodes are automatically also considered strict FP nodes -- this could
be fixed by adding one more range.)

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D71841
2020-01-02 16:59:45 +01:00
Jonas Paulsson 9fcebad5e5 [SystemZ] Add a mapping from "select register" to "load on condition" (2-addr).
The SELR(Mux) instructions can be converted to two-address form as LOCR(Mux)
instructions whenever one of the sources are the same reg as dest. By adding
this mapping in getTwoOperandOpcode(), we get:

- Two-address hints in getRegAllocationHints() for select register
  instructions.

- No need anymore for special handling in SystemZShortenInst.cpp -
  shortenSelect() removed.

The two-address hints are now added before the GRX32 hints, which should be
preferred.

Review: Ulrich Weigand
https://reviews.llvm.org/D68870
2019-12-20 10:44:58 -08:00
Jonas Paulsson 3174683e21 [SystemZ] Bugfix and improve the handling of CC values.
It was recently discovered that the handling of CC values was actually broken
since overflow was not properly handled ('nsw' flag not checked for).

Add and sub instructions now have a new target specific instruction flag
named SystemZII::CCIfNoSignedWrap. It means that the CC result can be used
instead of a compare with 0, but only if the instruction has the 'nsw' flag
set.

This patch also adds the improvements of conversion to logical instructions
and the analyzing of add with immediates, to be able to eliminate more
compares.

Review: Ulrich Weigand
https://reviews.llvm.org/D66868
2019-12-20 10:20:23 -08:00
Ulrich Weigand ede8293d7d [SystemZ][FPEnv] Enable strict vector FP extends/truncations
The back-end currently has special DAGCombine code to detect
cases where two floating-point extend or truncate operations
can be combined into a single vector operation.

This patch extends that support to also handle strict FP operations.

Note that currently only the case where both operations have the
same input chain are supported.  This already suffices to cover
the common case where the operations result from scalarizing a
non-legal vector type.  More general cases can be supported in
the future.
2019-12-20 15:36:56 +01:00
Philip Reames 8277c91cf3 [StackMaps] Be explicit about label formation [NFC] (try 2)
Recommit after making the same API change in non-x86 targets.  This has been build for all targets, and tested for effected ones.  Why the difference?  Because my disk filled up when I tried make check for all.

For auto-padding assembler support, we'll need to bundle the label with the instructions (nops or call sequences) so that they don't get separated.  This just rearranges the code to make the upcoming change more obvious.
2019-12-19 14:05:30 -08:00
Jonas Paulsson 6be1578895 [SystemZ] Recognize mrecord-mcount in backend
Emit the __mcount_loc section for all fentry calls.

Review: Ulrich Weigand
https://reviews.llvm.org/D71629
2019-12-19 09:06:18 -08:00
Ulrich Weigand 1946461344 [FPEnv] Strict versions of llvm.minimum/llvm.maximum
Add new intrinsics
   llvm.experimental.constrained.minimum
   llvm.experimental.constrained.maximum
as strict versions of llvm.minimum and llvm.maximum.

Includes SystemZ back-end support.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D71624
2019-12-18 21:35:28 +01:00
Jonas Paulsson ca520592c0 [Clang FE, SystemZ] Don't add "true" value for the "mnop-mcount" attribute.
Let the "mnop-mcount" function attribute simply be present or non-present.
Update SystemZ backend as well to use hasFnAttribute() instead.

Review: Ulrich Weigand
https://reviews.llvm.org/D71669
2019-12-18 11:04:13 -08:00
Ulrich Weigand d1c0f14be8 [SystemZ][FPEnv] Back-end support for STRICT_[SU]INT_TO_FP
As of b1d8576 there is middle-end support for STRICT_[SU]INT_TO_FP,
so this patch adds SystemZ back-end support as well.

The patch is SystemZ target specific except for adding SD patterns
strict_[su]int_to_fp and any_[su]int_to_fp to TargetSelectionDAG.td
as usual.
2019-12-17 18:24:05 +01:00
Jonas Paulsson 49f55dda01 [SystemZ] Improve verification of MachineOperands.
Now that the machine verifier will check for cases of register/immediate
MachineOperands and their correspondence to the MC instruction descriptor,
this patch adds the operand types to the descriptors where they were
previously missing. All MCOI::OPERAND_UNKNOWN operand types have been handled
to get a known type, except for G_... (global isel) instructions.

Review: Ulrich Weigand
https://reviews.llvm.org/D71494
2019-12-16 09:51:54 -08:00
Alex Richardson be15dfa88f [NFC] Use EVT instead of bool for getSetCCInverse()
Summary:
The use of a boolean isInteger flag (generally initialized using
VT.isInteger()) caused errors in our out-of-tree CHERI backend
(https://github.com/CTSRD-CHERI/llvm-project).

In our backend, pointers use a separate ValueType (iFATPTR) and therefore
.isInteger() returns false. This meant that getSetCCInverse() was using the
floating-point variant and generated incorrect code for us:
`(void *)0x12033091e < (void *)0xffffffffffffffff` would return false.

Committing this change will significantly reduce our merge conflicts
for each upstream merge.

Reviewers: spatel, bogner

Reviewed By: bogner

Subscribers: wuzish, arsenm, sdardis, nemanjai, jvesely, nhaehnle, hiraditya, kbarton, jrtc27, atanasyan, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70917
2019-12-13 12:22:03 +00:00
Jonas Paulsson 61f5ba5c32 [SystemZ] Implement the packed stack layout
Any llvm function with the "packed-stack" attribute will be compiled to use
the packed stack layout which reuses unused parts of the incoming register
save area. This is needed for building the Linux kernel.

Review: Ulrich Weigand
https://reviews.llvm.org/D70821
2019-12-12 10:26:03 -08:00
Reid Kleckner 5d986953c8 [IR] Split out target specific intrinsic enums into separate headers
This has two main effects:
- Optimizes debug info size by saving 221.86 MB of obj file size in a
  Windows optimized+debug build of 'all'. This is 3.03% of 7,332.7MB of
  object file size.
- Incremental step towards decoupling target intrinsics.

The enums are still compact, so adding and removing a single
target-specific intrinsic will trigger a rebuild of all of LLVM.
Assigning distinct target id spaces is potential future work.

Part of PR34259

Reviewers: efriedma, echristo, MaskRay

Reviewed By: echristo, MaskRay

Differential Revision: https://reviews.llvm.org/D71320
2019-12-11 18:02:14 -08:00
Reid Kleckner 85ba5f637a Rename TTI::getIntImmCost for instructions and intrinsics
Soon Intrinsic::ID will be a plain integer, so this overload will not be
possible.

Rename both overloads to ensure that downstream targets observe this as
a build failure instead of a runtime failure.

Split off from D71320

Reviewers: efriedma

Differential Revision: https://reviews.llvm.org/D71381
2019-12-11 18:00:20 -08:00
Ulrich Weigand ac473394ff [SystemZ] Fix 128-bit strict FMA expansion pre-z14
Before z14, we did not have any FMA instruction for 128-bit
floating-point, so the @llvm.fma.f128 intrinsic needs to be
expanded to a libcall on those platforms.

This worked correctly for regular FMA, but was implemented
incorrectly for the strict version.  This was not noticed
because we did not have test coverage for this case.

This patch fixes that incorrect expansion and adds the
missing test cases.
2019-12-11 16:32:08 +01:00
David Green be7a107070 [ARM] Teach the Arm cost model that a Shift can be folded into other instructions
This attempts to teach the cost model in Arm that code such as:
  %s = shl i32 %a, 3
  %a = and i32 %s, %b
Can under Arm or Thumb2 become:
  and r0, r1, r2, lsl #3

So the cost of the shift can essentially be free. To do this without
trying to artificially adjust the cost of the "and" instruction, it
needs to get the users of the shl and check if they are a type of
instruction that the shift can be folded into. And so it needs to have
access to the actual instruction in getArithmeticInstrCost, which if
available is added as an extra parameter much like getCastInstrCost.

We otherwise limit it to shifts with a single user, which should
hopefully handle most of the cases. The list of instruction that the
shift can be folded into include ADC, ADD, AND, BIC, CMP, EOR, MVN, ORR,
ORN, RSB, SBC and SUB. This translates to Add, Sub, And, Or, Xor and
ICmp.

Differential Revision: https://reviews.llvm.org/D70966
2019-12-09 10:24:33 +00:00
Ulrich Weigand a6fcdb211d [SystemZ] Fix build bot failures
My patch 9db13b5a7d seems to have
caused some build bots to fail due to warnings that appear only
when using -Wcovered-switch-default.

This patch is an attempt to fix this by trying to avoid both the warning
"default label in switch which covers all enumeration values"
for the inner switch statements and at the same time the warning
"this statement may fall through"
for the outer switch statement in getVectorComparison
(SystemZISelLowering.cpp).
2019-12-07 19:37:16 +01:00
Ulrich Weigand 9db13b5a7d [FPEnv] Constrained FCmp intrinsics
This adds support for constrained floating-point comparison intrinsics.

Specifically, we add:

      declare <ty2>
      @llvm.experimental.constrained.fcmp(<type> <op1>, <type> <op2>,
                                          metadata <condition code>,
                                          metadata <exception behavior>)
      declare <ty2>
      @llvm.experimental.constrained.fcmps(<type> <op1>, <type> <op2>,
                                           metadata <condition code>,
                                           metadata <exception behavior>)

The first variant implements an IEEE "quiet" comparison (i.e. we only
get an invalid FP exception if either argument is a SNaN), while the
second variant implements an IEEE "signaling" comparison (i.e. we get
an invalid FP exception if either argument is any NaN).

The condition code is implemented as a metadata string.  The same set
of predicates as for the fcmp instruction is supported (except for the
"true" and "false" predicates).

These new intrinsics are mapped by SelectionDAG codegen onto two new
ISD opcodes, ISD::STRICT_FSETCC and ISD::STRICT_FSETCCS, again
representing quiet vs. signaling comparison operations.  Otherwise
those nodes look like SETCC nodes, with an additional chain argument
and result as usual for strict FP nodes.  The patch includes support
for the common legalization operations for those nodes.

The patch also includes full SystemZ back-end support for the new
ISD nodes, mapping them to all available SystemZ instruction to
fully implement strict semantics (scalar and vector).

Differential Revision: https://reviews.llvm.org/D69281
2019-12-07 11:28:39 +01:00
Ulrich Weigand daee549b17 [FPEnv][SelectionDAG] Relax chain requirements
This patch implements the following changes:

1) SelectionDAGBuilder::visitConstrainedFPIntrinsic currently treats
each constrained intrinsic like a global barrier (e.g. a function call)
and fully serializes all pending chains. This is actually not required;
it is allowed for constrained intrinsics to be reordered w.r.t one
another or (nonvolatile) memory accesses. The MI-level scheduler already
allows for that flexibility, so it makes sense to allow it at the DAG
level as well.

This patch therefore changes the way chains for constrained intrisincs
are created, and handles them basically like load operations are handled.
This has the effect that constrained intrinsics are no longer serialized
against one another or (nonvolatile) loads. They are still serialized
against stores, but that seems hard to change with the current DAG chain
setup, and it also doesn't seem to be a big problem preventing DAG

2) The OPC_CheckFoldableChainNode check requires that each of the
intermediate nodes in a multi-node pattern match only has a single use.
This check tends to fail if those intermediate nodes are strict operations
as those have a chain output that typically indeed has another use.
However, we don't really need to consider chains here at all, since they
will all be rewritten anyway by UpdateChains later. Other parts of the
matcher therefore already ignore chains, but this hasOneUse check doesn't.

This patch replaces hasOneUse by a custom test that verifies there is no
more than one use of any non-chain output value.

In theory, this change could affect code unrelated to strict FP nodes,
but at least on SystemZ I could not find any single instance of that
happening

3) The SystemZ back-end currently does not allow matching multiply-and-
extend operations (32x32 -> 64bit or 64x64 -> 128bit FP multiply) for
strict FP operations.  This was not possible in the past due to the
problems described under 1) and 2) above.

With those issues fixed, it is now possible to fully support those
instructions in strict mode as well, and this patch does so.

Differential Revision: https://reviews.llvm.org/D70913
2019-12-06 11:02:11 +01:00
Roman Lebedev 9a20c79ddc
[NFC][KnownBits] Add getMinValue() / getMaxValue() methods
As it can be seen from accompanying cleanup, it is not unheard of
to write `~Known.Zero` meaning "what maximal value can this KnownBits
produce". But i think `~Known.Zero` isn't *that* self-explanatory,
as compared to a method with a name.

Note that not all `~Known.Zero` places were cleaned up,
only those where this arguably improves things.
2019-12-03 20:04:51 +03:00
Jonas Paulsson 3ec193fb52 [SystemZ] Don't build a PPA instruction with an immediate 0 operand.
The improvement in the machine verifier for operand types (D63973) discovered
a bad operand in a test using a PPA instruction. It was an immediate 0 where
a register was expected.

This patch fixes this (NFC) by now making the PPA second register operand
NoRegister instead of a zero immediate in the MIR.

Review: Ulrich Weigand
https://reviews.llvm.org/D70501
2019-11-26 11:21:01 +01:00
Jonas Paulsson a7d3f6933d [SystemZ] Return the right offsets from getCalleeSavedSpillSlots().
// Due to the SystemZ ABI, the DWARF CFA (Canonical Frame Address) is not
// equal to the incoming stack pointer, but to incoming stack pointer plus
// 160.  The getOffsetOfLocalArea() returned value is interpreted as "the
// offset of the local area from the CFA".

The immediate offsets into the Register save area returned by
getCalleeSavedSpillSlots() should take this offset into account, which this
patch makes sure of.

Patch and review by Ulrich Weigand.
https://reviews.llvm.org/D70427
2019-11-25 19:03:05 +01:00