Commit Graph

660 Commits

Author SHA1 Message Date
Ulrich Weigand 947f78ac27 [SystemZ] Fix/optimize vec_load_len and related intrinsics
When using vec_load/store_len_r with an immediate length operand
of 16 or larger, LLVM will currently emit an VLRL/VSTRL instruction
with that immediate.  This creates a valid encoding (which should be
supported by the assembler), but always traps at runtime.  This patch
fixes this by not creating VLRL/VSTRL in those cases.

This would result in loading the length into a register and
calling VLRLR/VSTRLR instead.  However, these operations with
a length of 15 or larger are in fact simply equivalent to a
full vector load or store.  And in fact the same holds true for
vec_load/store_len as well.

Therefore, add a DAGCombine rule to replace those operations with
plain vector loads or stores if the length is known at compile
time and equal or larger to 15.
2020-05-06 21:15:58 +02:00
Jonas Paulsson c84461ba8d [SystemZ] Fix test case.
Remove bad kill flags fom load-and-test.mir as discovered by
https://reviews.llvm.org/D78586: "[MachineVerifier] Add more checks for
registers in live-in lists".

Review: Ulrich Weigand
2020-04-28 09:43:03 +02:00
Jonas Paulsson 036242b868 [SystemZ] Bugfix in adjustSubwordCmp()
adjustSubwordCmp() should not optimize a load of an i1 value. This is
achieved by checking that the size and store-size of the MemoryVT are the
same.

Fixes https://bugs.llvm.org/show_bug.cgi?id=45511.

Review: Ulrich Weigand

Differential Revision: https://reviews.llvm.org/D78187
2020-04-15 12:58:39 +02:00
Jonas Paulsson 36d4421f50 [LoopDataPrefetch + SystemZ] Let target decide on prefetching for each loop.
This patch adds

- New arguments to getMinPrefetchStride() to let the target decide on a
  per-loop basis if software prefetching should be done even with a stride
  within the limit of the hw prefetcher.

- New TTI hook enableWritePrefetching() to let a target do write prefetching
  by default (defaults to false).

- In LoopDataPrefetch:

  - A search through the whole loop to gather information before emitting any
    prefetches. This way the target can get information via new arguments to
    getMinPrefetchStride() and emit prefetches more selectively. Collected
    information includes: Does the loop have a call, how many memory
    accesses, how many of them are strided, how many prefetches will cover
    them. This is NFC to before as long as the target does not change its
    definition of getMinPrefetchStride().

  - If a previous access to the same exact address was 'read', and the
    current one is 'write', make it a 'write' prefetch.

  - If two accesses that are covered by the same prefetch do not dominate
    each other, put the prefetch in a block that dominates both of them.

  - If a ConstantMaxTripCount is less than ItersAhead, then skip the loop.

- A SystemZ implementation of getMinPrefetchStride().

Review: Ulrich Weigand, Michael Kruse

Differential Revision: https://reviews.llvm.org/D70228
2020-04-02 14:57:46 +02:00
Jonas Paulsson f481d48893 [SystemZ] Improve foldMemoryOperandImpl().
Fold MS(G)RKC -> MS(G)C.

Review: Ulrich Weigand

Differential Revision: https://reviews.llvm.org/D76771
2020-03-31 17:17:51 +02:00
Jonas Paulsson f09b891d4a [SystemZ] Improve foldMemoryOperandImpl()
A spilled load of an immediate can use MVHI/MVGHI instead.
A compare of a spilled register against an immediate can use CHSI/CGHSI.
A logical compare can use CLFHSI/CLGHSI.

Review: Ulrich Weigand

Differential Revision: https://reviews.llvm.org/D76055
2020-03-25 16:21:08 +01:00
Jinsong Ji 816ad48c82 [NFC][RUIP] Small debug output refine
Add a new line, so that we always print MI in a new line,
before and after UpdateRegMask, for easier check..
2020-03-24 03:29:45 +00:00
Jonas Paulsson 9adc7fc3cd [SystemZ] Perform instruction shortening for fused fp ops.
Replace single-lane (W... form) vector "multiply and add" and "multiply and
subtract" instructions with equivalent floating point instructions whenever
possible in SystemZShortenInst.

Review: Ulrich Weigand

Differential Revision: https://reviews.llvm.org/D76370
2020-03-23 14:12:13 +01:00
Simon Pilgrim 68224c1952 [TargetLowering] Only demand a rotation's modulo amount bits
ISD::ROTL/ROTR rotation values are guaranteed to act as a modulo amount, so for power-of-2 bitwidths we only need the lowest bits.

Differential Revision: https://reviews.llvm.org/D76201
2020-03-17 21:23:46 +00:00
Jonas Paulsson 132f25bcca [SystemZ] Avoid scalarization of [SU]INT_TO_FP ISD-nodes.
The type legalizer will scalarize vector conversions from integer to floating
point if the source element size is less than that of the result.

This is avoided now by inserting a zero/sign-extension of the source vector
before type legalization.

Review: Ulrich Weigand

Differential revision: https://reviews.llvm.org/D75978
2020-03-16 13:07:42 +01:00
Simon Pilgrim 775bf62698 [SystemZ] Regenerate rotate/shift tests 2020-03-15 16:42:46 +00:00
Jonas Paulsson 62ff9960d3 [SystemZ] Improve foldMemoryOperandImpl().
Swap the compare operands if LHS is spilled while updating the CCMask:s of
the CC users. This is relatively straight forward since the live-in lists for
the CC register can be assumed to be correct during register allocation
(thanks to 659efa2).

Also fold a spilled operand of an LOCR/SELR into an LOC(G).

Review: Ulrich Weigand

Differential Revision: https://reviews.llvm.org/D67437
2020-03-10 15:54:47 +01:00
Jonas Paulsson ae4d39c9e4 [SystemZ] Copy Access registers and CC with the correct register class.
On SystemZ there are a set of "access registers" that can be copied in and
out of 32-bit GPRs with special instructions. These instructions can only
perform the copy using low 32-bit parts of the 64-bit GPRs. However, the
default register class for 32-bit integers is GRX32, which also contains the
high 32-bit part registers.

In order to never end up with a case of such a COPY into a high reg, this
patch adds a new simple pre-RA pass that selects such COPYs into target
instructions.

This pass also handles COPYs from CC (Condition Code register), and COPYs to
CC can now also be emitted from a high reg in copyPhysReg().

Fixes: https://bugs.llvm.org/show_bug.cgi?id=44254

Review: Ulrich Weigand.

Differential Revision: https://reviews.llvm.org/D75014
2020-03-03 16:41:09 +01:00
Jonas Paulsson 237625757a [SystemZ] Bugfix for backchain with packed-stack
The incoming back chain slot was implicitly allocated whenever a GPR was
saved in SystemZFrameLowering::getRegSpillOffset(), but in cases where no
GPRs were saved/restored this did not take effect.

Review: Ulrich Weigand

Differential Revision: https://reviews.llvm.org/D75367
2020-03-03 15:03:01 +01:00
Jonas Paulsson cdcce3cabf [SystemZ] Also accept ISD::USUBO in shouldFormOverflowOp().
Forming subtract with overflow is beneficial on SystemZ, just like additions.

Review: Ulrich Weigand

Differential Revision: https://reviews.llvm.org/D75290
2020-03-03 14:38:57 +01:00
Craig Topper a5fa778882 [LegalizeTypes] Scalarize non-byte sized loads in WidenRecRes_Load and SplitVecResLoad
Should fix PR42803 and PR44902

Differential Revision: https://reviews.llvm.org/D74590
2020-02-24 15:14:33 -08:00
Jonas Paulsson 82879c2913 [SystemZ] Support the kernel back chain.
In order to build the Linux kernel, the back chain must be supported with
packed-stack. The back chain is then stored topmost in the register save
area.

Review: Ulrich Weigand

Differential Revision: https://reviews.llvm.org/D74506
2020-02-23 13:42:36 -08:00
Jonas Paulsson 0eddeeab29 [ValueTracking] Improve isKnownNonNaN() to recognize zero splats.
isKnownNonNaN() could not recognize a zero splat because that is a
ConstantAggregateZero which is-a ConstantData but not a ConstantDataVector.

Patch makes a ConstantAggregateZero return true.

Review: Thomas Lively

Differential Revision: https://reviews.llvm.org/D74263
2020-02-19 09:35:36 -08:00
Simon Pilgrim 7a554270c0 [SystemZ] Regenerate risbg tests. NFCI.
Pre-commit for some upcoming SimplifyDemandedBits bitrotate handling.
2020-02-19 16:39:28 +00:00
James Clarke b3cd44f80b Use SETNE directly rather than SUB/SETNE 0 for stack guard check
Summary:
Backends should fold the subtraction into the comparison, but not all
seem to. Moreover, on targets where pointers are not integers, such as
CHERI, an integer subtraction is not appropriate. Instead we should just
compare the two pointers directly, as this should work everywhere and
potentially generate more efficient code.

Reviewers: bogner, lebedev.ri, efriedma, t.p.northover, uweigand, sunfish

Reviewed By: lebedev.ri

Subscribers: dschuff, sbc100, arichardson, jgravelle-google, hiraditya, aheejin, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74454
2020-02-18 13:21:26 +00:00
Fangrui Song 6b14814e10 [AsmPrinter] Omit unique ID for .stack_sizes
Follow-up for D74006.
2020-02-14 21:25:06 -08:00
Yuanfang Chen 4ad7685258 Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`"""
This reverts commit 80a34ae311 with fixes.

Previously, since bots turning on EXPENSIVE_CHECKS are essentially turning on
MachineVerifierPass by default on X86 and the fact that
inline-asm-avx-v-constraint-32bit.ll and inline-asm-avx512vl-v-constraint-32bit.ll
are not expected to generate functioning machine code, this would go
down to `report_fatal_error` in MachineVerifierPass. Here passing
`-verify-machineinstrs=0` to make the intent explicit.
2020-02-13 10:16:06 -08:00
Yuanfang Chen 17122ec10a Revert "Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`""""
This reverts commit bb51d24330.
2020-02-13 10:08:05 -08:00
Yuanfang Chen bb51d24330 Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`"""
This reverts commit 80a34ae311 with fixes.

On bots llvm-clang-x86_64-expensive-checks-ubuntu and
llvm-clang-x86_64-expensive-checks-debian only,
llc returns 0 for these two tests unexpectedly. I tweaked the RUN line a little
bit in the hope that LIT is the culprit since this change is not in the
codepath these tests are testing.
llvm\test\CodeGen\X86\inline-asm-avx-v-constraint-32bit.ll
llvm\test\CodeGen\X86\inline-asm-avx512vl-v-constraint-32bit.ll
2020-02-13 10:02:53 -08:00
Yuanfang Chen 80a34ae311 Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`""
This reverts commit rGcd5b308b828e, rGcd5b308b828e, rG8cedf0e2994c.

There are issues to be investigated for polly bots and bots turning on
EXPENSIVE_CHECKS.
2020-02-11 20:41:53 -08:00
Yuanfang Chen 8cedf0e299 Reland "[Support] make report_fatal_error `abort` instead of `exit`"
Summary:
Reland D67847 after D73742 is committed. Replace `sys::Process::Exit(1)`
with `abort` in `report_fatal_error`.

After this patch, for tools turning on `CrashRecoveryContext`,
crash handler installed by `CrashRecoveryContext` is called unless
they installed a non-returning handler using `llvm::install_fatal_error_handler`
like `cc1_main` currently does.

Reviewers: rnk, MaskRay, aganea, hans, espindola, jhenderson

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

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D74456
2020-02-11 18:20:40 -08:00
Jonas Paulsson 509bac030a [SystemZ] Fix new test case for expensive checks.
It needs 'tracksRegLiveness: true' to pass the machine verifier.
2020-02-11 11:33:41 -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
Jinsong Ji 01edae1271 [AsmPrinter] Print FP constant in hexadecimal form instead
Printing floating point number in decimal is inconvenient for humans.
Verbose asm output will print out floating point values in comments, it
helps.

But in lots of cases, users still need additional work to covert the
decimal back to hex or binary to check the bit patterns,
especially when there are small precision difference.

Hexadecimal form is one of the supported form in LLVM IR, and easier for
debugging.

This patch try to print all FP constant in hex form instead.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D73566
2020-02-07 16:00:55 +00:00
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 e943329ba0 [SystemZ] Add 'REQUIRES:' or '-mtriple' to some newly added tests.
Needed to fix buildbots.
2020-02-04 10:52:10 -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
Krzysztof Parzyszek 020041d99b Update spelling of {analyze,insert,remove}Branch in strings and comments
These names have been changed from CamelCase to camelCase, but there were
many places (comments mostly) that still used the old names.

This change is NFC.
2020-01-21 10:15:38 -06:00
Yuanfang Chen 6e24c6037f Revert "[Support] make report_fatal_error `abort` instead of `exit`"
This reverts commit 647c3f4e47.

Got bots failure from sanitizer-windows and maybe others.
2020-01-15 17:52:25 -08:00
Yuanfang Chen 647c3f4e47 [Support] make report_fatal_error `abort` instead of `exit`
Summary:
This patch could be treated as a rebase of D33960. It also fixes PR35547.
A fix for `llvm/test/Other/close-stderr.ll` is proposed in D68164. Seems
the consensus is that the test is passing by chance and I'm not
sure how important it is for us. So it is removed like in D33960 for now.
The rest of the test fixes are just adding `--crash` flag to `not` tool.

** The reason it fixes PR35547 is

`exit` does cleanup including calling class destructor whereas `abort`
does not do any cleanup. In multithreading environment such as ThinLTO or JIT,
threads may share states which mostly are ManagedStatic<>. If faulting thread
tearing down a class when another thread is using it, there are chances of
memory corruption. This is bad 1. It will stop error reporting like pretty
stack printer; 2. The memory corruption is distracting and nondeterministic in
terms of error message, and corruption type (depending one the timing, it
could be double free, heap free after use, etc.).

Reviewers: rnk, chandlerc, zturner, sepavloff, MaskRay, espindola

Reviewed By: rnk, MaskRay

Subscribers: wuzish, jholewinski, qcolombet, dschuff, jyknight, emaste, sdardis, nemanjai, jvesely, nhaehnle, sbc100, arichardson, jgravelle-google, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, lenary, s.egerton, pzheng, cfe-commits, MaskRay, filcab, davide, MatzeB, mehdi_amini, hiraditya, steven_wu, dexonsmith, rupprecht, seiya, llvm-commits

Tags: #llvm, #clang

Differential Revision: https://reviews.llvm.org/D67847
2020-01-15 17:05:13 -08:00
Ulrich Weigand 81ee484484 [FPEnv] Fix chain handling regression after 04a8696
Code in getRoot made the assumption that every node in PendingLoads
must always itself have a dependency on the current DAG root node.

After the changes in 04a8696, it turns out that this assumption no
longer holds true, causing wrong codegen in some cases (e.g. stores
after constrained FP intrinsics might get deleted).

To fix this, we now need to make sure that the TokenFactor created
by getRoot always includes the previous root, if there is no implicit
dependency already present.

The original getControlRoot code already has exactly this check,
so this patch simply reuses that code now for getRoot as well.
This fixes the regression.

NFC if no constrained FP intrinsic is present.
2020-01-14 14:10:57 +01:00
Ulrich Weigand 04a86966fb [FPEnv] Fix chain handling for fpexcept.strict nodes
We need to ensure that fpexcept.strict nodes are not optimized away even if
the result is unused. To do that, we need to chain them into the block's
terminator nodes, like already done for PendingExcepts.

This patch adds two new lists of pending chains, PendingConstrainedFP and
PendingConstrainedFPStrict to hold constrained FP intrinsic nodes without
and with fpexcept.strict markers. This allows not only to solve the above
problem, but also to relax chains a bit further by no longer flushing all
FP nodes before a store or other memory access. (They are still flushed
before nodes with other side effects.)

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D72341
2020-01-13 14:38:49 +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
Ulrich Weigand 14cd4a5b32 [SystemZ] Extend fp-strict-alias test case
Explicitly add test for fpexcept.maytrap intrinsics.
2020-01-07 12:44:51 +01:00
Ulrich Weigand 4814b68b7a [SystemZ] Fix python failure in test case
With recent Python the Large/spill-02.py test failed with an error:
TypeError: can't multiply sequence by non-int of type 'float'
2020-01-07 10:26:37 +01:00
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
Fangrui Song a36ddf0aa9 Migrate function attribute "no-frame-pointer-elim"="false" to "frame-pointer"="none" as cleanups after D56351 2019-12-24 16:27:51 -08:00
Fangrui Song 502a77f125 Migrate function attribute "no-frame-pointer-elim" to "frame-pointer"="all" as cleanups after D56351 2019-12-24 15:57:33 -08:00
Ulrich Weigand 0d3f782e41 [FPEnv][X86] More strict int <-> FP conversion fixes
Fix several several additional problems with the int <-> FP conversion
logic both in common code and in the X86 target. In particular:

- The STRICT_FP_TO_UINT expansion emits a floating-point compare. This
  compare can raise exceptions and therefore needs to be a strict compare.
  I've made it signaling (even though quiet would also be correct) as
  signaling is the more usual default for an LT. This code exists both
  in common code and in the X86 target.

- The STRICT_UINT_TO_FP expansion algorithm was incorrect for strict mode:
  it emitted two STRICT_SINT_TO_FP nodes and then used a select to choose one
  of the results. This can cause spurious exceptions by the STRICT_SINT_TO_FP
  that ends up not chosen. I've fixed the algorithm to use only a single
  STRICT_SINT_TO_FP instead.

- The !isStrictFPEnabled logic in DoInstructionSelection would sometimes do
  the wrong thing because it calls getOperationAction using the result VT.
  But for some opcodes, incuding [SU]INT_TO_FP, getOperationAction needs to
  be called using the operand VT.

- Remove some (obsolete) code in X86DAGToDAGISel::Select that would mutate
  STRICT_FP_TO_[SU]INT to non-strict versions unnecessarily.

Reviewed by: craig.topper

Differential Revision: https://reviews.llvm.org/D71840
2019-12-23 21:11:45 +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
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