32115 Commits

Author SHA1 Message Date
Denis Antrushin
e04fe9aefd [Statepoint] Fix bug found by sanitaizer.
Statepoint has no static operands, so it cannot be verified
against MCInstrDescr. Revert NumDefs change introduced by ef658ebd629.
2020-07-16 23:06:53 +03:00
Nadav Rotem
a394aa1b97 [LiveVariables] Replace std::vector with SmallVector.
Replace std::vector with SmallVector to reduce the number of mallocs.
This method is frequently executed, and the number of elements in the
vector is typically small.

https://reviews.llvm.org/D83920
2020-07-16 11:39:54 -07:00
Matt Arsenault
9d3e56e2ee DAG: Try scalarizing when expanding saturating add/sub
In an upcoming AMDGPU patch, the scalar cases will be legal and vector
ops should be scalarized, rather than producing a long sequence of
vector ops which will also need to be scalarized.

Use a lazy heuristic that seems to work and improves the thumb2 MVE
test.
2020-07-16 14:05:16 -04:00
Denis Antrushin
ef658ebd62 MIR Statepoint refactoring. Part 1: Basic MI level changes.
Basic support for variadic-def MIR Statepoint:
- Change TableGen STATEPOINT description to variadic out list
  (For self-documentation purpose; by itself it does not affect
  code generation in any way).
- Update StatepointOpers helper class to handle variadic defs.
- Update MachineVerifier to properly handle them, too.

With this change, new Statepoint instruction can be passed through
backend (excluding ISEL) without errors.

Full change set is available at D81603.
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D81645
2020-07-17 00:57:21 +07:00
Matt Arsenault
023883a834 IR: Rename Argument::hasPassPointeeByValueAttr to prepare for byref
When the byref attribute is added, there will need to be two similar
functions for the existing cases which have an associate value copy,
and byref which does not. Most, but not all of the existing uses will
use the existing version.

The associated size function added by D82679 also needs to
contextually differ, and will help eliminate a few places still
relying on pointee element types.
2020-07-16 13:50:49 -04:00
Petar Avramovic
6850033ca6 AMDGPU/GlobalISel: Legalize s64->s16 G_SITOFP/G_UITOFP
Add widenScalar for TypeIdx == 0 for G_SITOFP/G_UITOFP.
Legailize, using widenScalar, as s64->s32 G_SITOFP/G_UITOFP
followed by s32->s16 G_FPTRUNC.

Differential Revision: https://reviews.llvm.org/D83880
2020-07-16 16:31:57 +02:00
James Y Knight
60433c63ac Remove TwoAddressInstructionPass::sink3AddrInstruction.
This function has a bug which will incorrectly reschedule instructions
after an INLINEASM_BR (which can branch). (The bug may also allow
scheduling past a throwing-CALL, I'm not certain.)

I could fix that bug, but, as the removed FIXME notes, it's better to
attempt rescheduling before converting to 3-addr form, as that may
remove the need to convert in the first place. In fact, the code to do
such reordering was added to this pass only a few months later, in
2011, via the addition of the function rescheduleMIBelowKill. That
code does not contain the same bug.

The removal of the sink3AddrInstruction function is not a no-op: in
some cases it would move an instruction post-conversion, when
rescheduleMIBelowKill would not move the instruction pre-converison.
However, this does not appear to be important: the machine instruction
scheduler can reorder the after-conversion instructions, in any case.

This patch fixes a kernel panic 4.4 LTS x86_64 Linux kernels, when
built with clang after 4b0aa5724feaa89a9538dcab97e018110b0e4bc3.

Link: https://github.com/ClangBuiltLinux/linux/issues/1085

Differential Revision: https://reviews.llvm.org/D83708
2020-07-16 10:02:52 -04:00
Kerry McLaughlin
2762da0a16 [SVE][CodeGen] Legalisation of masked loads and stores
Summary:
This patch modifies IncrementMemoryAddress to use a vscale
when calculating the new address if the data type is scalable.

Also adds tablegen patterns which match an extract_subvector
of a legal predicate type with zip1/zip2 instructions

Reviewers: sdesmalen, efriedma, david-arm

Reviewed By: efriedma, david-arm

Subscribers: tschuett, hiraditya, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D83137
2020-07-16 10:55:45 +01:00
Quentin Colombet
294be6b5d3 [CalcSpillWeights] Propagate the fact that a live-interval is not spillable
When we calculate the weight of a live-interval, add some code to
check if the original live-interval was markied as not spillable and
if so, progagate that information down to the new interval.

Previously we would just recompute a weight for the new interval,
thus, we could in theory just spill live-intervals marked as not
spillable by just splitting them. That goes against the spirit of
a non-spillable live-interval.

E.g., previously we could do:
v1 =  // v1 must not be spilled
...
= v1

Split:
v1 = // v1 must not be spilled
...
v2 = v1 // v2 can be spilled
...
v3 = v2 // v3 can be spilled
= v3

There's no test case for that one as we would need to split a
non-spillable live-interval without using LiveRangeEdit to see this
happening.
RegAlloc inserts non-spillable intervals only as part of the spilling
mechanism, thus at this point the intervals are not splittable anymore.
On top of that, RegAlloc uses the LiveRangeEdit API, which already
properly propagate that information.

In other words, this could only happen if a target was to mark
a live-interval as not spillable before register allocation and
split it without using LRE, e.g., through
LiveIntervals::splitSeparateComponent.
2020-07-15 17:57:36 -07:00
Hiroshi Yamauchi
f233b92f92 [PGO][PGSO] Add profile guided size optimization to LegalizeDAG.
Reviewers: davidxl

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D83333
2020-07-15 10:03:38 -07:00
Cameron McInally
ae51a70030 [Legalize] Hoist invariant condition in ExpandVectorBuildThroughStack(...)
The operands of a BUILD_VECTOR must all have the same type, so we can hoist this invariant condition out of the loop.

Differential Revision: https://reviews.llvm.org/D83882
2020-07-15 11:05:20 -05:00
Tim Northover
37b96d51d0 CodeGenPrep: remove AssertingVH references before deleting dead instructions.
CodeGenPrepare keeps fairly close track of various instructions it's
seen, particularly GEPs, in maps and vectors. However, sometimes those
instructions become dead and get removed while it's still executing.
This triggers AssertingVH references to them in an asserts build and
could lead to miscompiles in a release build (I've only seen a later
segfault though).

So this patch adds a callback to
RecursivelyDeleteTriviallyDeadInstructions which can make sure the
instruction about to be deleted is removed from CodeGenPrepare's data
structures.
2020-07-15 15:19:21 +01:00
Tim Northover
5165b2b5fd AArch64+ARM: make LLVM consider system registers volatile.
Some of the system registers readable on AArch64 and ARM platforms
return different values with each read (for example a timer counter),
these shouldn't be hoisted outside loops or otherwise interfered with,
but the normal @llvm.read_register intrinsic is only considered to read
memory.

This introduces a separate @llvm.read_volatile_register intrinsic and
maps all system-registers on ARM platforms to use it for the
__builtin_arm_rsr calls. Registers declared with asm("r9") or similar
are unaffected.
2020-07-15 09:47:36 +01:00
Roger Ferrer Ibanez
14bc5e149d [DAGCombiner] Rebuild (setcc x, y, ==) from (xor (xor x, y), 1)
The existing code already considered this case. Unfortunately a typo in
the condition prevents it from triggering. Also the existing code, had
it run, forgot to do the folding.

This fixes PR42876.

Differential Revision: https://reviews.llvm.org/D65802
2020-07-15 07:34:22 +00:00
Krzysztof Pszeniczny
c3e6555616 Call Frame Information (CFI) Handling for Basic Block Sections
This patch handles CFI with basic block sections, which unlike DebugInfo does
not support ranges. The DWARF standard explicitly requires emitting separate
CFI Frame Descriptor Entries for each contiguous fragment of a function. Thus,
the CFI information for all callee-saved registers (possibly including the
frame pointer, if necessary) have to be emitted along with redefining the
Call Frame Address (CFA), viz. where the current frame starts.

CFI directives are emitted in FDE’s in the object file with a low_pc, high_pc
specification. So, a single FDE must point to a contiguous code region unlike
debug info which has the support for ranges. This is what complicates CFI for
basic block sections.

Now, what happens when we start placing individual basic blocks in unique
sections:

* Basic block sections allow the linker to randomly reorder basic blocks in the
address space such that a given basic block can become non-contiguous with the
original function.
* The different basic block sections can no longer share the cfi_startproc and
cfi_endproc directives. So, each basic block section should emit this
independently.
* Each (cfi_startproc, cfi_endproc) directive will result in a new FDE that
caters to that basic block section.
* Now, this basic block section needs to duplicate the information from the
entry block to compute the CFA as it is an independent entity. It cannot refer
to the FDE of the original function and hence must duplicate all the stuff that
is needed to compute the CFA on its own.
* We are working on a de-duplication patch that can share common information in
FDEs in a CIE (Common Information Entry) and we will present this as a follow up
patch. This can significantly reduce the duplication overhead and is
particularly useful when several basic block sections are created.
* The CFI directives are emitted similarly for registers that are pushed onto
the stack, like callee saved registers in the prologue. There are cfi
directives that emit how to retrieve the value of the register at that point
when the push happened. This has to be duplicated too in a basic block that is
floated as a separate section.

Differential Revision: https://reviews.llvm.org/D79978
2020-07-14 12:54:12 -07:00
Logan Smith
a19461d9e1 [NFC] Add 'override' keyword where missing in include/ and lib/.
This fixes warnings raised by Clang's new -Wsuggest-override, in preparation for enabling that warning in the LLVM build. This patch also removes the virtual keyword where redundant, but only in places where doing so improves consistency within a given file. It also removes a couple unnecessary virtual destructor declarations in derived classes where the destructor inherited from the base class is already virtual.

Differential Revision: https://reviews.llvm.org/D83709
2020-07-14 09:47:29 -07:00
Paul Walker
6e198aae1d [SelectionDAG] Prevent warnings when extracting fixed length vector from scalable.
ComputeNumSignBits and computeKnownBits both trigger "Scalable flag
may be dropped" warnings when a fixed length vector is extracted
from a scalable vector.  This patch assumes nothing about the
demanded elements thus matching the behaviour when extracting a
scalable vector from a scalable vector.

Differential Revision: https://reviews.llvm.org/D83642
2020-07-14 11:12:56 +00:00
Sam Elliott
1d15bbb9d9 Revert "[RISCV] Avoid Splitting MBB in RISCVExpandPseudo"
This reverts commit 97106f9d80f6ba1bf5eafbd5a6f88d72913ec5a1.

This is based on feedback from https://reviews.llvm.org/D82988#2147105
2020-07-14 11:15:01 +01:00
David Sherwood
3b8eaf26db [SVE][CodeGen] Fix implicit TypeSize->uint64_t conversion in TransformFPLoadStorePair
In DAGCombiner::TransformFPLoadStorePair we were dropping the scalable
property of TypeSize when trying to create an integer type of equivalent
size. In fact, this optimisation makes no sense for scalable types
since we don't know the size at compile time. I have changed the code
to bail out when encountering scalable type sizes.

I've added a test to

  llvm/test/CodeGen/AArch64/sve-fp.ll

that exercises this code path. The test already emits an error if it
encounters warnings due to implicit TypeSize->uint64_t conversions.

Differential Revision: https://reviews.llvm.org/D83572
2020-07-14 08:07:30 +01:00
Amara Emerson
64eb3a4915 [AArch64][GlobalISel] Add post-legalize combine for sext_inreg(trunc(sextload)) -> copy
On AArch64 we generate redundant G_SEXTs or G_SEXT_INREGs because of this.

Differential Revision: https://reviews.llvm.org/D81993
2020-07-13 20:27:45 -07:00
zuojian lin
fefe6a6642 Fix undefined behavior in DWARF emission
Caused by uninitialized load of llvm::DwarfDebug::PrevCU:
llvm::DwarfCompileUnit::addRange () at ../lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp:276
llvm::DwarfDebug::endFunctionImpl () at ../lib/CodeGen/AsmPrinter/DwarfDebug.cpp:1586
llvm::DebugHandlerBase::endFunction () at ../lib/CodeGen/AsmPrinter/DebugHandlerBase.cpp:319
llvm::AsmPrinter::EmitFunctionBody () at ../lib/CodeGen/AsmPrinter/AsmPrinter.cpp:1230
llvm::ARMAsmPrinter::runOnMachineFunction () at ../lib/Target/ARM/ARMAsmPrinter.cpp:161

Most of the DebugInfo tests under `LLVM_LIT_ARGS:STRING=-sv --vg` prior to this fix, and pass with the fix applied.

Reviewed By: aprantl, dblaikie

Differential Revision: https://reviews.llvm.org/D81631
2020-07-13 18:32:36 -07:00
Matt Arsenault
23ec773d19 GlobalISel: Implement fewerElementsVector for saturating add/sub 2020-07-13 14:46:40 -04:00
Matt Arsenault
6a8c11a11f GlobalISel: Implement widenScalar for saturating add/sub
Add a placeholder legality rule for AMDGPU until the rest of the
actions are handled.
2020-07-13 14:46:40 -04:00
Sanjay Patel
8779b11410 [DAGCombiner] rot i16 X, 8 --> bswap X
We have this generic transform in IR (instcombine),
but as shown in PR41098:
http://bugs.llvm.org/PR41098
...the pattern may emerge in codegen too.

x86 has a potential refinement/reversal opportunity here,
but that should come later or needs a target hook to
avoid the transform. Converting to bswap is the more
specific form, so we should use it if it is available.
2020-07-13 12:01:53 -04:00
Sanjay Patel
2df46a5743 [DAGCombiner] allow load/store merging if pairs can be rotated into place
This carves out an exception for a pair of consecutive loads that are
reversed from the consecutive order of a pair of stores. All of the
existing profitability/legality checks for the memops remain between
the 2 altered hunks of code.

This should give us the same x86 base-case asm that gcc gets in
PR41098 and PR44895:
http://bugs.llvm.org/PR41098
http://bugs.llvm.org/PR44895

I think we are missing a potential subsequent conversion to use "movbe"
if the target supports that. That might be similar to what AArch64
would use to get "rev16".

Differential Revision: https://reviews.llvm.org/D83567
2020-07-13 08:57:00 -04:00
Sanjay Patel
f1bbf3acb4 Revert "[DAGCombiner] allow load/store merging if pairs can be rotated into place"
This reverts commit 591a3af5c7acc05617c0eacf6ae4f76bd8a9a6ce.
The commit message was cut off and failed to include the review citation.
2020-07-13 08:55:29 -04:00
Sanjay Patel
591a3af5c7 [DAGCombiner] allow load/store merging if pairs can be rotated into place
This carves out an exception for a pair of consecutive loads that are
reversed from the consecutive order of a pair of stores. All of the
existing profitability/legality checks for the memops remain between
the 2 altered hunks of code.

This should give us the same x86 base-case asm that gcc gets in
PR41098 and PR44895:i
http://bugs.llvm.org/PR41098
http://bugs.llvm.org/PR44895

I think we are missing a potential subsequent conversion to use "movbe"
if the target supports that. That might be similar to what AArch64
would use to get "rev16".

Differential Revision:
2020-07-13 08:53:06 -04:00
Kerry McLaughlin
afcc9a81d2 [SVE][Codegen] Add a helper function for pointer increment logic
Summary:
Helper used when splitting load & store operations to calculate
the pointer + offset for the high half of the split

Reviewers: efriedma, sdesmalen, david-arm

Reviewed By: efriedma

Subscribers: tschuett, hiraditya, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D83577
2020-07-13 10:53:40 +01:00
Petar Avramovic
fd85b40aee [GlobalISel][InlineAsm] Fix buildCopy for inputs
Check that input size matches size of destination reg class.
Attempt to extend input size when needed.

Differential Revision: https://reviews.llvm.org/D83384
2020-07-13 10:52:33 +02:00
Sanjay Patel
39009a8245 [DAGCombiner] tighten fast-math constraints for fma fold
fadd (fma A, B, (fmul C, D)), E --> fma A, B, (fma C, D, E)

This is only allowed when "reassoc" is present on the fadd.

As discussed in D80801, this transform goes beyond
what is allowed by "contract" FMF (-ffp-contract=fast).
That is because we are fusing the trailing add of 'E' with a
multiply, but without "reassoc", the code mandates that the
products A*B and C*D are added together before adding in 'E'.

I've added this example to the LangRef to try to clarify the
meaning of "contract". If that seems reasonable, we should
probably do something similar for the clang docs because
there does not appear to be any formal spec for the behavior
of -ffp-contract=fast.

Differential Revision: https://reviews.llvm.org/D82499
2020-07-12 08:51:49 -04:00
Alexandre Ganea
b71499ac9e Revert "Re-land [CodeView] Add full repro to LF_BUILDINFO record"
This reverts commit add59ecb34e3003311b7e2318b16a0ef10c76d79 and 41d2813a5faea1c18b7d329109e0287c5cd9ffea.
2020-07-10 19:46:16 -04:00
Alexandre Ganea
add59ecb34 Re-land [CodeView] Add full repro to LF_BUILDINFO record
This patch adds some missing information to the LF_BUILDINFO which allows for rebuilding an .OBJ without any external dependency but the .OBJ itself (other than the compiler executable).

Some tools need this information to reproduce a build without any knowledge of the build system. The LF_BUILDINFO therefore stores a full path to the compiler, the PWD (which is the CWD at program startup), a relative or absolute path to the TU, and the full CC1 command line. The command line needs to be freestanding (not depend on any environment variable). In the same way, MSVC doesn't store the provided command-line, but an expanded version (somehow their equivalent of CC1) which is also freestanding.

For more information see PR36198 and D43002.

Differential Revision: https://reviews.llvm.org/D80833
2020-07-10 13:59:28 -04:00
Sanjay Patel
02fec9d2a5 [DAGCombiner] move/rename variables for readability; NFC 2020-07-10 11:28:51 -04:00
David Sherwood
da731894a2 [CodeGen] Replace calls to getVectorNumElements() in DAGTypeLegalizer::SetSplitVector
In DAGTypeLegalizer::SetSplitVector I have changed calls in the assert
from getVectorNumElements() to getVectorElementCount(), since this
code path works for both fixed and scalable vectors.

This fixes up one warning in the test:

  sve-sext-zext.ll

Differential Revision: https://reviews.llvm.org/D83196
2020-07-10 08:29:17 +01:00
David Sherwood
229dfb4728 [CodeGen] Replace calls to getVectorNumElements() in SelectionDAG::SplitVector
This patch replaces some invalid calls to getVectorNumElements() with calls
to getVectorMinNumElements() instead, since the code paths changed in this
patch work for both fixed and scalable vector types.

Fixes warnings in this test:

  sve-sext-zext.ll

Differential Revision: https://reviews.llvm.org/D83203
2020-07-10 08:11:30 +01:00
Sanjay Patel
a46cf40240 [DAGCombiner] convert if-chain in store merging to switch; NFC 2020-07-09 17:20:04 -04:00
Sanjay Patel
b476e6a642 [DAGCombiner] add helper function for store merging of loaded values; NFC 2020-07-09 17:20:04 -04:00
Sanjay Patel
f98a602c2e [DAGCombiner] add helper function for store merging of extracts; NFC 2020-07-09 17:20:03 -04:00
Sanjay Patel
8d74cb01b7 [DAGCombiner] add helper function for store merging of constants; NFC 2020-07-09 17:20:03 -04:00
Sanjay Patel
6890e2a17b [DAGCombiner] add helper function to manage list of consecutive stores; NFC 2020-07-09 17:20:03 -04:00
Christopher Tetreault
ff5b9a7b3b [SVE] Remove calls to VectorType::getNumElements from CodeGen
Reviewers: efriedma, fpetrogalli, sdesmalen, RKSimon, arsenm

Reviewed By: RKSimon

Subscribers: wdng, tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82210
2020-07-09 12:43:36 -07:00
Sam Elliott
97106f9d80 [RISCV] Avoid Splitting MBB in RISCVExpandPseudo
Since the `RISCVExpandPseudo` pass has been split from
`RISCVExpandAtomicPseudo` pass, it would be nice to run the former as
early as possible (The latter has to be run as late as possible to
ensure correctness). Running earlier means we can reschedule these pairs
as we see fit.

Running earlier in the machine pass pipeline is good, but would mean
teaching many more passes about `hasLabelMustBeEmitted`. Splitting the
basic blocks also pessimises possible optimisations because some
optimisations are MBB-local, and others are disabled if the block has
its address taken (which is notionally what `hasLabelMustBeEmitted`
means).

This patch uses a new approach of setting the pre-instruction symbol on
the AUIPC instruction to a temporary symbol and referencing that. This
avoids splitting the basic block, but allows us to reference exactly the
instruction that we need to. Notionally, this approach seems more
correct because we do actually want to address a specific instruction.

This then allows the pass to be moved much earlier in the pass pipeline,
before both scheduling and register allocation. However, to do so we
must leave the MIR in SSA form (by not redefining registers), and so use
a virtual register for the intermediate value. By using this virtual
register, this pass now has to come before register allocation.

Reviewed By: luismarques, asb

Differential Revision: https://reviews.llvm.org/D82988
2020-07-09 13:54:13 +01:00
Lucas Prates
fc39a9ca0e [CodeGen] Matching promoted type for 16-bit integer bitcasts from fp16 operand
Summary:
When legalizing a biscast operation from an fp16 operand to an i16 on a
target that requires both input and output types to be promoted to
32-bits, an assertion can fail when building the new node due to a
mismatch between the the operation's result size and the type specified to
the node.

This patches fix the issue by making sure the bit width of the types
match for the FP_TO_FP16 node, covering the difference with an extra
ANYEXTEND operation.

Reviewers: ostannard, efriedma, pirama, jmolloy, plotfi

Reviewed By: efriedma

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82552
2020-07-09 09:46:17 +01:00
serge-sans-paille
a60c31fd62 Fix return status of AtomicExpandPass
Correctly reflect change in the return status.

Differential Revision: https://reviews.llvm.org/D83457
2020-07-09 10:27:48 +02:00
Qiu Chaofan
4254ed5c32 [Legalizer] Fix wrong operand in split vector helper
This should be a typo introduced in D69275, which may cause an unknown
segment fault in getNode.

Reviewed By: uweigand

Differential Revision: https://reviews.llvm.org/D83376
2020-07-09 09:57:29 +08:00
Matt Arsenault
18bd821f02 DAG: Remove redundant finalizeLowering call
9cac4e6d1403554b06ec2fc9d834087b1234b695/D32628 intended to eliminate
this, and move all isel pseudo expansion to FinalizeISel. This was a
bad rebase or something, and failed to actually delete this call.

GlobalISel also has a redundant call of finalizeLowering. However, it
requires more work to remove it since it currently triggers a lot of
verifier errors in tests.
2020-07-08 18:48:20 -04:00
Matt Arsenault
2ec5fc0c61 DAG: Remove redundant handling of reg fixups
It looks like 9cac4e6d1403554b06ec2fc9d834087b1234b695 accidentally
added a second copy of this from a bad rebase or something. This
second copy was added, and the finalizeLowering call was not deleted
as intended.
2020-07-08 18:32:43 -04:00
Matt Arsenault
74a148ad39 GlobalISel: Verify G_BITCAST changes the type
Updated the AArch64 tests the best I could with my vague, inferred
understanding of AArch64 register banks. As far as I can tell, there
is only one 32-bit/64-bit type which will use the gpr register bank,
so we have to use the fpr bank for the other operand.
2020-07-08 17:16:27 -04:00
Sanjay Patel
1265eb2d5f [DAGCombiner] clean up in mergeConsecutiveStores(); NFC 2020-07-08 14:48:05 -04:00
Sanjay Patel
12c2271e53 [DAGCombiner] fix code comment and improve readability; NFC 2020-07-08 14:48:05 -04:00