Commit Graph

4279 Commits

Author SHA1 Message Date
Simonas Kazlauskas a2eca31da2 Test cases for rem-seteq fold with illegal types
This also briefly tests a larger set of architectures than the more
exhaustive functionality tests for AArch64 and x86.

As requested in D88785

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D98339
2021-03-12 16:28:04 +02:00
Daniel Sanders 134a179dee [mir] Change 'undef' for MMO base addresses to 'unknown-address'
Differential Revision: https://reviews.llvm.org/D98100
2021-03-10 16:46:44 -08:00
Craig Topper 0eb405c3b8 [SelectionDAG] Add computeKnownBits support for ISD::USUBSAT.
The result of ISD::USUBSAT will never be larger than the LHS. We
can use this to put a bound on the number of leading zeros.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D98133
2021-03-07 09:48:42 -08:00
Daniel Sanders 9fc2be6f28 [mir] Fix confusing MIR when MMO's value is nullptr but offset is non-zero
:: (store 1 + 4, addrspace 1)
->
:: (store 1 into undef + 4, addrspace 1)

An offset without a base isn't terribly useful but it's convenient to update
the offset without checking the value. For example, when breaking apart
stores into smaller units

Differential Revision: https://reviews.llvm.org/D97812
2021-03-04 10:34:30 -08:00
Arthur Eubanks 040c1b49d7 Move EntryExitInstrumentation pass location
This seems to be more of a Clang thing rather than a generic LLVM thing,
so this moves it out of LLVM pipelines and as Clang extension hooks into
LLVM pipelines.

Move the post-inline EEInstrumentation out of the backend pipeline and
into a late pass, similar to other sanitizer passes. It doesn't fit
into the codegen pipeline.

Also fix up EntryExitInstrumentation not running at -O0 under the new
PM. PR49143

Reviewed By: hans

Differential Revision: https://reviews.llvm.org/D97608
2021-03-01 10:08:10 -08:00
Craig Topper fe50be12c8 [LegalizeIntegerTypes] Further improve ExpandIntRes_SADDSUBO for targets where SADDO/SSUBO aren't supported.
Rather than converting 3 signbits to bools and comparing them,
we can do bitwise logic on the whole vector and convert the
resulting sign bit to a bool at the end.

This is still a different algorithm than what we do in LegalizeDAG
through expandSADDOSSUBO. That algorithm needs to know that the
RHS of SSUBO is > 0, but that's costly when the type is split.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D97325
2021-02-24 10:05:38 -08:00
David Green 03892a27d6 [ARM] Expand the range of allowed post-incs in load/store optimizer
Currently the load/store optimizer will only fold in increments of the
same size as the load/store. This patch expands that to any legal
immediate for the post-inc instruction.

This is a recommit of 3b34b06fc5 with correctness fixes and extra
tests.

Differential Revision: https://reviews.llvm.org/D95885
2021-02-24 08:46:15 +00:00
David Green 8fa2bbaed9 [ARM] Mir test for pre/postinc ldstopt combines. NFC 2021-02-23 22:27:06 +00:00
Craig Topper eb165090bb [LegalizeIntegerTypes] Improve ExpandIntRes_SADDSUBO codegen on targets without SADDO/SSUBO.
This code creates 3 setccs that need to be expanded. It was
creating a sign bit test as setge X, 0 which is non-canonical.
Canonical would be setgt X, -1. This misses the special case in
IntegerExpandSetCCOperands for sign bit tests that assumes
canonical form. If we don't hit this special case we end up
with a multipart setcc instead of just checking the sign of
the high part.

To fix this I've reversed the polarity of all of the setccs to
setlt X, 0 which is canonical. The rest of the logic should
still work. This seems to produce better code on RISCV which
lacks a setgt instruction.

This probably still isn't the best code sequence we could use here.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D97181
2021-02-23 09:40:32 -08:00
Sjoerd Meijer e1c3bf6afe [ARM] do not consider sp as deprecated for ldm/stm
Early versions of the ARMv7 reference manuals considered the sp register
as a deprecated register for ldm/stm familiy of instructions. However,
later versions such as ARM DDI 0406C.d added a note to the Appendix:

D9.3 Use of the SP as a general-purpose register
Most ARM instructions, unlike Thumb instructions, provide exactly the
same access to the SP as to R0-R12. This means that it is possible to
use the SP as a general-purpose register.  Earlier issues of this manual
deprecated the use of SP in an ARM instruction, in any way that is
deprecated, not permitted, or not possible in the corresponding
Thumb instruction. However, user feedback indicates a number of cases
where these instructions are useful. Therefore, ARM no longer deprecates
these instruction uses.
Also Armv8 manuals no longer consider SP as deprecated register for ldm/
stm A32 instructions.

Furthermore, GNU as also does not print a deprecated warning when using
SP with those instructions.

Drop deprecation warning for pop/ldm/push/stm instructions.

Patch by: Stefan Agner.

Differential Revision: https://reviews.llvm.org/D82692
2021-02-23 13:26:18 +00:00
David Green ebb6583e02 [ARM] Add pre/post inc tests of various sizes. NFC 2021-02-23 10:53:22 +00:00
David Green 7a5c26e99a Revert "[ARM] Expand the range of allowed post-incs in load/store optimizer"
This reverts commit 3b34b06fc5 as runtime
errors were reported.
2021-02-19 13:15:10 +00:00
David Green 3b34b06fc5 [ARM] Expand the range of allowed post-incs in load/store optimizer
Currently the load/store optimizer will only fold in increments of the
same size as the load/store. This patch expands that to any legal
immediate for the post-inc instruction.

Differential Revision: https://reviews.llvm.org/D95885
2021-02-18 14:59:02 +00:00
David Green 1a6744e3dc [ARM] Add larger than legal ICmp costs
A v8i32 compare will produce a v8i1 predicate, but during codegen the
v8i32 will be split into two v4i32, potentially requiring two v4i1
predicates to be merged into a single v8i1. Because this merging of two
v4i1's into a v8i1 is very expensive, we need to make the cost of the
compare equally high.

This patch adds the cost of that to ARMTTIImpl::getCmpSelInstrCost.
Because we don't know whether the user of the predicate can be split,
and the cost model is mostly pre-instruction, we may be pessimistic but
that should only be for larger and legal types. This also adds min/max
detection to the costmodel where it can be detected, to keep those in
line with the cost of simple min/max instructions. Otherwise for the
most part, costs that were already expensive have become more expensive.

Differential Revision: https://reviews.llvm.org/D96692
2021-02-18 11:42:17 +00:00
David Green 1fbb3287fc [ARM] MVE ICmp costing tests. NFC 2021-02-18 10:50:34 +00:00
Sjoerd Meijer f78aa8b2c2 [LSR] Add a flag that overrides the target's preferred addressing mode
This adds a new flag -lsr-preferred-addressing-mode to override the target's
preferred addressing mode. It replaces flag -lsr-backedge-indexing, which is
equivalent to preindexed addressing that is one of the options that
-lsr-preferred-addressing-mode accepts.

Differential Revision: https://reviews.llvm.org/D96855
2021-02-17 16:50:21 +00:00
David Green a838a4f69f [ARM] Extend search for increment in load/store optimizer
Currently the findIncDecAfter will only look at the next instruction for
post-inc candidates in the load/store optimizer. This extends that to a
search through the current BB, until an instruction that modifies or
uses the increment reg is found. This allows more post-inc load/stores
and ldm/stm's to be created, especially in cases where a schedule might
move instructions further apart.

We make sure not to look any further for an SP, as that might invalidate
stack slots that are still in use.

Differential Revision: https://reviews.llvm.org/D95881
2021-02-15 13:17:21 +00:00
Simon Pilgrim 60ba5397df [DAG] PromoteIntRes_ADDSUBSHLSAT - use promoted ISD::USUBSAT directly
As discussed on D96413, as long as the promoted bits of the args are zero we can use the basic ISD::USUBSAT pattern directly, without the shifting like we do for other ops.

I think something similar should be possible for ISD::UADDSAT as well, which I'll look at later.

Also, create a ISD::USUBSAT node directly - this will be expanded back by the legalizer later on if necessary.

Differential Revision: https://reviews.llvm.org/D96622
2021-02-13 12:35:10 +00:00
Serge Pavlov 816053bc71 [FPEnv][ARM] Implement lowering of llvm.set.rounding
Differential Revision: https://reviews.llvm.org/D96501
2021-02-13 11:16:29 +07:00
Simon Pilgrim 4841a225b7 [DAG] Move basic USUBSAT pattern matches from X86 to DAGCombine
Begin transitioning the X86 vector code to recognise sub(umax(a,b) ,b) or sub(a,umin(a,b)) USUBSAT patterns to make it more generic and available to all targets.

This initial patch just moves the basic umin/umax patterns to DAG, removing some vector-only checks on the way - these are some of the patterns that the legalizer will try to expand back to so we can be reasonably relaxed about matching these pre-legalization.

We can handle the trunc(sub(..))) variants as well, which helps with patterns where we were promoting to a wider type to detect overflow/saturation.

The remaining x86 code requires some cleanup first - some of it isn't actually tested etc. I also need to resurrect D25987.

Differential Revision: https://reviews.llvm.org/D96413
2021-02-12 18:22:57 +00:00
Lukas Sommer 6577cef9b0 [CodeGen] New pass: Replace vector intrinsics with call to vector library
This patch adds a pass to replace calls to vector intrinsics (i.e., LLVM
intrinsics operating on vector operands) with calls to a vector library.

Currently, calls to LLVM intrinsics are only replaced with calls to vector
libraries when scalar calls to intrinsics are vectorized by the Loop- or
SLP-Vectorizer.

With this pass, it is now possible to replace calls to LLVM intrinsics
already operating on vector operands, e.g., if such code was generated
by MLIR. For the replacement, information from the TargetLibraryInfo,
e.g., as specified via -vector-library is used.

This is a re-try of the original commit 2303e93e66 that was reverted
due to pass manager problems. Other minor changes have also been made.

Differential Revision: https://reviews.llvm.org/D95373
2021-02-12 12:53:27 -05:00
Sanjay Patel c981f6f8e1 Revert "[Codegen][ReplaceWithVecLib] add pass to replace vector intrinsics with calls to vector library"
This reverts commit 2303e93e66.
Investigating bot failures.
2021-02-05 15:10:11 -05:00
Lukas Sommer 2303e93e66 [Codegen][ReplaceWithVecLib] add pass to replace vector intrinsics with calls to vector library
This patch adds a pass to replace calls to vector intrinsics
(i.e., LLVM intrinsics operating on vector operands) with
calls to a vector library.

Currently, calls to LLVM intrinsics are only replaced with
calls to vector libraries when scalar calls to intrinsics are
vectorized by the Loop- or SLP-Vectorizer.

With this pass, it is now possible to replace calls to LLVM
intrinsics already operating on vector operands, e.g., if
such code was generated by MLIR. For the replacement,
information from the TargetLibraryInfo, e.g., as specified
via -vector-library is used.

Differential Revision: https://reviews.llvm.org/D95373
2021-02-05 14:25:19 -05:00
Ayke van Laethem aecdf15cc7
[ARM] Do not emit ldrexd/strexd on Cortex-M chips
The ldrexd/strexd instructions are not supported on M-class chips, see
for example
https://developer.arm.com/documentation/dui0489/e/arm-and-thumb-instructions/memory-access-instructions/ldrex-and-strex
which says:

> All these 32-bit Thumb instructions are available in ARMv6T2 and
> above, except that LDREXD and STREXD are not available in the ARMv7-M
> architecture.

Looking at the ARMv8-M architecture, it appears that these instructions
aren't supported either. The Architecture Reference Manual lists
ldrex/strex but not ldrexd/strexd:
https://developer.arm.com/documentation/ddi0553/bn/

Godbolt example on LLVM 11.0.0, which incorrectly emits ldrexd/strexd
instructions: https://llvm.godbolt.org/z/5qqPnE

Differential Revision: https://reviews.llvm.org/D95891
2021-02-04 21:55:34 +01:00
David Green 649a3d00df [ARM] Handle f16 in GeneratePerfectShuffle
This new f16 shuffle under Neon would hit an assert in
GeneratePerfectShuffle as it would try to treat a f16 vector as an i8.
Add f16 handling, treating them like an i16.

Differential Revision: https://reviews.llvm.org/D95446
2021-02-04 11:14:52 +00:00
David Green 5805521207 [ARM] Simplify VMOVRRD from extracts of buildvectors
Under the softfp calling convention, we are often left with
VMOVRRD(extract(bitcast(build_vector(a, b, c, d)))) for the return value
of the function. These can be simplified to a,b or c,d directly,
depending on the value of the extract.

Big endian is a little different because the bitcast switches the lanes
around, meaning we end up with b,a or d,c.

Differential Revision: https://reviews.llvm.org/D94989
2021-02-01 16:09:25 +00:00
David Green ad12e6ee95 [ARM] Turn sext_inreg(VGetLaneu) into VGetLaneu
This adds a DAG combine for converting sext_inreg of VGetLaneu into
VGetLanes, providing the types match correctly.

Differential Revision: https://reviews.llvm.org/D95073
2021-02-01 11:10:35 +00:00
Roman Lebedev ddc4b56eef
[ExpandMemCmpPass] Preserve Dominator Tree, if available
This finishes getting rid of all the avoidable Dominator Tree recalculations
in X86 optimized codegen pipeline.
2021-01-30 01:14:51 +03:00
Roman Lebedev 056385921d
[ScalarizeMaskedMemIntrin] Preserve Dominator Tree, if avaliable
This de-pessimizes the arguably more usual case of no masked mem intrinsics,
and gets rid of one more Dominator Tree recalculation.

As per llvm/test/CodeGen/X86/opt-pipeline.ll,
there's one more Dominator Tree recalculation left, we could get rid of.
2021-01-29 01:11:36 +03:00
Roman Lebedev 6617529a1d
[CodeGen][DwarfEHPrepare] Preserve Dominator Tree
Now that D94827 has flipped the switch, and SimplifyCFG is officially marked
as production-ready regarding Dominator Tree preservation,
we can update this user pass to also preserve Dominator Tree.

This is a geomean compile-time win of `-0.05%`..`-0.08%`.
https://llvm-compile-time-tracker.com/compare.php?from=51a25846c198cff00abad0936f975167357afa6f&to=082499aac236a5c141e50a9e77870d5be2de5f0b&stat=instructions

Differential Revision: https://reviews.llvm.org/D95548
2021-01-28 14:11:34 +03:00
David Green c1c1944e69 [ARM] Regenerate constant hoisting test. NFC 2021-01-28 10:37:16 +00:00
Roman Lebedev 51a25846c1
[CodeGen] SafeStack: preserve DominatorTree if it is avaliable
While this is mostly NFC right now, because only ARM happens
to run this pass with DomTree available before it,
and required after it, more backends will be affected once
the SimplifyCFG's switch for domtree preservation is flipped,
and DwarfEHPrepare also preserves the domtree.
2021-01-27 18:32:35 +03:00
David Green 9e2768a3d9 [ARM] Add neon FP16 scalar_to_vector patterns.
This adds some simple fp16 scalar_to_vector patterns, preventing a
selection failure if this came up.

Differential Revision: https://reviews.llvm.org/D95427
2021-01-27 09:59:15 +00:00
Adhemerval Zanella dad55c2218 [ARM] [ELF] Fix ARMMaterializeGV for Indirect calls
Recent shouldAssumeDSOLocal changes (introduced by 961f31d8ad)
do not take in consideration the relocation model anymore.  The ARM
fast-isel pass uses the function return to set whether a global symbol
is loaded indirectly or not, and without the expected information
llvm now generates an extra load for following code:

```
$ cat test.ll
@__asan_option_detect_stack_use_after_return = external global i32
define dso_local i32 @main(i32 %argc, i8** %argv) #0 {
entry:
  %0 = load i32, i32* @__asan_option_detect_stack_use_after_return,
align 4
  %1 = icmp ne i32 %0, 0
  br i1 %1, label %2, label %3

2:
  ret i32 0

3:
  ret i32 1
}

attributes #0 = { noinline optnone }

$ lcc test.ll -o -
[...]
main:
        .fnstart
[...]
        movw    r0, :lower16:__asan_option_detect_stack_use_after_return
        movt    r0, :upper16:__asan_option_detect_stack_use_after_return
        ldr     r0, [r0]
        ldr     r0, [r0]
        cmp     r0, #0
[...]
```

And without 'optnone' it produces:
```
[...]
main:
        .fnstart
[...]
        movw    r0, :lower16:__asan_option_detect_stack_use_after_return
        movt    r0, :upper16:__asan_option_detect_stack_use_after_return
        ldr     r0, [r0]
        clz     r0, r0
        lsr     r0, r0, #5
        bx      lr

[...]
```

This triggered a lot of invalid memory access in sanitizers for
arm-linux-gnueabihf.  I checked this patch both a stage1 built with
gcc and a stage2 bootstrap and it fixes all the Linux sanitizers
issues.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D95379
2021-01-26 15:57:55 -03:00
David Green af03324984 [ARM] Disable sign extended SSAT pattern recognition.
I may have given bad advice, and skipping sext_inreg when matching SSAT
patterns is not valid on it's own. It at least needs to sext_inreg the
input again, but as far as I can tell is still only valid based on
demanded bits. For the moment disable that part of the combine,
hopefully reimplementing it in the future more correctly.
2021-01-22 14:07:48 +00:00
David Green 476de8cea3 [ARM] Add new and regenerate SSAT tests. NFC
Some of these new tests should be creating SSAT. They will be fixed in a
followup.
2021-01-22 10:42:36 +00:00
Simon Pilgrim 69bc0990a9 [DAGCombiner] Enable SimplifyDemandedBits vector support for TRUNCATE (REAPPLIED).
Add DemandedElts support inside the TRUNCATE analysis.

REAPPLIED - this was reverted by @hans at rGa51226057fc3 due to an issue with vector shift amount types, which was fixed in rG935bacd3a724 and an additional test case added at rG0ca81b90d19d

Differential Revision: https://reviews.llvm.org/D56387
2021-01-21 13:01:34 +00:00
Hans Wennborg a51226057f Revert "[DAGCombiner] Enable SimplifyDemandedBits vector support for TRUNCATE"
It caused "Vector shift amounts must be in the same as their first arg"
asserts in Chromium builds. See the code review for repro instructions.

> Add DemandedElts support inside the TRUNCATE analysis.
>
> Differential Revision: https://reviews.llvm.org/D56387

This reverts commit cad4275d69.
2021-01-20 20:06:55 +01:00
Simon Pilgrim cad4275d69 [DAGCombiner] Enable SimplifyDemandedBits vector support for TRUNCATE
Add DemandedElts support inside the TRUNCATE analysis.

Differential Revision: https://reviews.llvm.org/D56387
2021-01-20 15:39:58 +00:00
Yvan Roux 244ad228f3 [ARM][MachineOutliner] Add stack fixup feature
This patch handles cases where we have to save/restore the link register
into the stack and and load/store instruction which use the stack are
part of the outlined region. It checks that there will be no overflow
introduced by the new offset and fixup these instructions accordingly.

Differential Revision: https://reviews.llvm.org/D92934
2021-01-19 10:59:09 +01:00
David Green 69295815ed [ARM] Update test target triple. NFC 2021-01-18 16:36:00 +00:00
David Green 1454724215 [ARM] Align blocks that are not fallthough targets
If the previous block in a function does not fallthough, adding nop's to
align it will never be executed. This means we can freely (except for
codesize) align more branches. This happens in constantislandspass (as
it cannot happen later) and only happens at aggressive optimization
levels as it does increase codesize.

Differential Revision: https://reviews.llvm.org/D94394
2021-01-16 22:19:35 +00:00
Oliver Stannard 3676ef1053 [ARM][GISel] Treat calls as variadic even if only fixed arguments provided
For the ARM hard-float calling convention, calls to variadic functions
need to be treated diffrently, even if only the fixed arguments are
provided.

This fixes GCC-C-execute-pr68390 in the test-suite, which is failing on
the ARM GlobaISel bot.
2021-01-15 09:37:01 +00:00
Sam Tebbs 60fda8ebb6 [ARM] Add a pass that re-arranges blocks when there is a backwards WLS branch
Blocks can be laid out such that a t2WhileLoopStart branches backwards. This is forbidden by the architecture and so it fails to be converted into a low-overhead loop. This new pass checks for these cases and moves the target block, fixing any fall-through that would then be broken.

Differential Revision: https://reviews.llvm.org/D92385
2021-01-13 17:23:00 +00:00
Mircea Trofin 05e90cefeb [NFC] Disallow unused prefixes under llvm/test/CodeGen
This patch finishes addressing unused prefixes under CodeGen: 2
remaining tests fixed, and then undo-ing the lit.local.cfg changes under
various subdirs and moving the policy under CodeGen.

Differential Revision: https://reviews.llvm.org/D94430
2021-01-11 12:32:18 -08:00
Paul Robinson be179b9946 [FastISel] NFC: Remove obsolete -fast-isel-sink-local-values option
This option is not used for anything after #c161665 (D91737).
This commit reapplies #a474657.
2021-01-11 09:32:49 -08:00
Paul Robinson c161775dec [FastISel] Flush local value map on every instruction
Local values are constants or addresses that can't be folded into
the instruction that uses them. FastISel materializes these in a
"local value" area that always dominates the current insertion
point, to try to avoid materializing these values more than once
(per block).

https://reviews.llvm.org/D43093 added code to sink these local
value instructions to their first use, which has two beneficial
effects. One, it is likely to avoid some unnecessary spills and
reloads; two, it allows us to attach the debug location of the
user to the local value instruction. The latter effect can
improve the debugging experience for debuggers with a "set next
statement" feature, such as the Visual Studio debugger and PS4
debugger, because instructions to set up constants for a given
statement will be associated with the appropriate source line.

There are also some constants (primarily addresses) that could be
produced by no-op casts or GEP instructions; the main difference
from "local value" instructions is that these are values from
separate IR instructions, and therefore could have multiple users
across multiple basic blocks. D43093 avoided sinking these, even
though they were emitted to the same "local value" area as the
other instructions. The patch comment for D43093 states:

  Local values may also be used by no-op casts, which adds the
  register to the RegFixups table. Without reversing the RegFixups
  map direction, we don't have enough information to sink these
  instructions.

This patch undoes most of D43093, and instead flushes the local
value map after(*) every IR instruction, using that instruction's
debug location. This avoids sometimes incorrect locations used
previously, and emits instructions in a more natural order.

In addition, constants materialized due to PHI instructions are
not assigned a debug location immediately; instead, when the
local value map is flushed, if the first local value instruction
has no debug location, it is given the same location as the
first non-local-value-map instruction.  This prevents PHIs
from introducing unattributed instructions, which would either
be implicitly attributed to the location for the preceding IR
instruction, or given line 0 if they are at the beginning of
a machine basic block.  Neither of those consequences is good
for debugging.

This does mean materialized values are not re-used across IR
instruction boundaries; however, only about 5% of those values
were reused in an experimental self-build of clang.

(*) Actually, just prior to the next instruction. It seems like
it would be cleaner the other way, but I was having trouble
getting that to work.

This reapplies commits cf1c774d and dc35368c, and adds the
modification to PHI handling, which should avoid problems
with debugging under gdb.

Differential Revision: https://reviews.llvm.org/D91734
2021-01-11 08:32:36 -08:00
Paul Robinson e5eb5c8a7f NFC: Use -LABEL more
There were a number of tests needing updates for D91734, and I added a
bunch of LABEL directives to help track down where those had to go.
These directives are an improvement independent of the functional
patch, so I'm committing them as their own separate patch.
2021-01-11 08:14:58 -08:00
David Green 1ae762469f [ARM] Update and regenerate test checks. NFC 2021-01-08 14:54:16 +00:00
David Green 63dce70b79 [ARM] Handle any extend whilst lowering addw/addl/subw/subl
Same as a9b6440edd, use zanyext to treat any_extends as zero extends
during lowering to create addw/addl/subw/subl nodes.

Differential Revision: https://reviews.llvm.org/D93835
2021-01-06 11:26:39 +00:00