CodeGenPrepare has a strategy for moving dbg.values so that a value's
definition always dominates its debug users. This cleanup was happening
too early (before certain CGP transforms were run), resulting in some
dbg.value use-before-def errors.
Perform this cleanup as late as possible to avoid use-before-def.
llvm-svn: 340370
In optimizeSelectInst, when scanning for candidate selects to rewrite
into branches, scan past debug intrinsics. This makes the debug-enabled
and non-debug paths through optimizeSelectInst more congruent.
NFC because every select is eventually visited either way.
llvm-svn: 340368
Summary:
Computing the remaining latency can be very expensive especially
on graphs of N nodes where the number of edges approaches N^2.
This reduces the compile time of a pathological case with the
AMDGPU backend from ~7.5 seconds to ~3 seconds. This test case has
a basic block with 2655 stores, each with somewhere between 500
and 1500 successors and predecessors.
Reviewers: atrick, MatzeB, airlied, mareko
Reviewed By: mareko
Subscribers: tpr, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D50486
llvm-svn: 340346
Summary:
Catchpads and cleanuppads are not funclet entries; they are only EH
scope entries. We already dont't set `isEHFuncletEntry` for catchpads.
This patch does the same thing for cleanuppads.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D50654
llvm-svn: 340330
Summary:
When RegisterCoalescer::reMaterializeTrivialDef is substituting
a register use in a DBG_VALUE instruction, and the old register
is a subreg, and the new register is a physical register,
then we need to use substPhysReg in order to extract the correct
subreg.
Reviewers: wmi, aprantl
Reviewed By: wmi
Subscribers: hiraditya, MatzeB, qcolombet, tpr, llvm-commits
Differential Revision: https://reviews.llvm.org/D50844
llvm-svn: 340326
Summary:
So far, `isReturn` property is used to mean both a return instruction
from a functon and the end of an EH scope, a scope that starts with a EH
scope entry BB and ends with a catchret or a cleanupret instruction.
Because WinEH uses funclets, all EH-scope-ending instructions are also
real return instruction from a function. But for wasm, they only serve
as the end marker of an EH scope but not a return instruction that
exits a function. This mismatch caused incorrect prolog and epilog
generation in wasm EH scopes. This patch fixes this.
This patch is in the same vein with rL333045, which splits
`MachineBasicBlock::isEHFuncletEntry` into `isEHFuncletEntry` and
`isEHScopeEntry`.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D50653
llvm-svn: 340325
In removeCopyByCommutingDef, segments from the source live range are
copied into (and merged with) the segments of the target live range.
This is performed for all subranges of the source interval. It can
happen that there will be subranges of the target interval that had
no corresponding subranges in the source interval, and in such cases
these subrages will not be updated. Since the copy being coalesced
is about to be removed, these ranges need to be updated by removing
the segments that are started by the copy.
llvm-svn: 340318
This reverts commit d1341152d91398e9a882ba2ee924147ea2f9b589.
This patch originally made use of Nested MachineIRBuilder buildInstr
calls, and since order of argument processing is not well defined, the
instructions were built slightly in a different order (still correct).
I've removed the nested buildInstr calls to have a defined order now.
Patch was tested by Mikael.
llvm-svn: 340309
Summary:
Previously a BUNDLE instruction inherited the DebugLoc from the
first instruction in the bundle, even if that DebugLoc had no
DILocation. With this commit this is changed into selecting the
first DebugLoc that has a DILocation, by searching among the
bundled instructions.
The idea is to reduce amount of bundles that are lacking
debug locations.
Reviewers: #debug-info, JDevlieghere
Reviewed By: JDevlieghere
Subscribers: JDevlieghere, mattd, llvm-commits
Differential Revision: https://reviews.llvm.org/D50639
llvm-svn: 340267
During combining, ReduceLoadWdith is used to combine AND nodes that
mask loads into narrow loads. This patch allows the mask to be a
shifted constant. This results in a narrow load which is then left
shifted to compensate for the new offset.
Differential Revision: https://reviews.llvm.org/D50432
llvm-svn: 340261
This reduces most of the sdiv stages (the MULHS, shifts etc.) to just zero/identity values and use the numerator scale factor to multiply by +1/-1.
llvm-svn: 340260
Summary:
RegisterCoalescer::reMaterializeTrivialDef used to assert that
the input register was live in. But as shown by the new
coalesce-dead-lanes.mir test case that seems to be a valid
scenario. We now return false instead of the assert, simply
avoiding to remat the dead def.
Normally a COPY of an undef value is eliminated by
eliminateUndefCopy(). Although we only do that when the
destination isn't a physical register. So the situation
above should be limited to the case when we copy an undef
value to a physical register.
Reviewers: kparzysz, wmi, tpr
Reviewed By: kparzysz
Subscribers: MatzeB, qcolombet, tpr, llvm-commits
Differential Revision: https://reviews.llvm.org/D50842
llvm-svn: 340255
1. Change the software pipeliner to use unknown size instead of dropping
memory operands. It used to do it before, but MachineInstr::mayAlias
did not handle it correctly.
2. Recognize UnknownSize in MachineInstr::mayAlias.
3. Print and parse UnknownSize in MIR.
Differential Revision: https://reviews.llvm.org/D50339
llvm-svn: 340208
getTargetCustom() requires values for "Kind" in the constructor
that are not in the PSVKind enum. Passing a value that is not inside
an enum as an argument to a constructor of the type of the enum is
UB. Changing to the underlying type of the enum would solve the UB
Differential Revision: https://reviews.llvm.org/D50909
llvm-svn: 340200
This reverts commit 7debc334e6421bb5251ef8f18e97166dfc7dd787.
I missed updating legalizer-info-validation.mir as I had assertions
turned off in my build and that specific test requires asserts. Fixed it
now.
llvm-svn: 340197
Only adds support to the existing 'large element' scalar/vector to 'small element' vector bitcasts.
Handle the case where the sign bit extends to only part of the small elements.
llvm-svn: 340169
Only adds support to the existing 'large element' scalar/vector to 'small element' vector bitcasts.
The next step would be to support cases where the large elements aren't all sign bits, and determine the small element equivalent based on the demanded elements.
llvm-svn: 340143
Summary:
I believe this restores the behavior we had before r339147.
Fixes PR38622.
Reviewers: RKSimon, chandlerc, spatel
Reviewed By: chandlerc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D50936
llvm-svn: 340120
There are two forms for label debug information in DWARF format.
1. Labels in a non-inlined function:
DW_TAG_label
DW_AT_name
DW_AT_decl_file
DW_AT_decl_line
DW_AT_low_pc
2. Labels in an inlined function:
DW_TAG_label
DW_AT_abstract_origin
DW_AT_low_pc
We will collect label information from DBG_LABEL. Before every DBG_LABEL,
we will generate a temporary symbol to denote the location of the label.
The symbol could be used to get DW_AT_low_pc afterwards. So, we create a
mapping between 'inlined label' and DBG_LABEL MachineInstr in DebugHandlerBase.
The DBG_LABEL in the mapping is used to query the symbol before it.
The AbstractLabels in DwarfCompileUnit is used to process labels in inlined
functions.
We also keep a mapping between scope and labels in DwarfFile to help to
generate correct tree structure of DIEs.
It also generates label debug information under global isel.
Differential Revision: https://reviews.llvm.org/D45556
llvm-svn: 340039
This patch performs a widening transformation of bitwise atomicrmw
{or,xor,and} and applies it prior to tryExpandAtomicRMW. This operates
similarly to convertCmpXchgToIntegerType. For these operations, the i8/i16
atomicrmw can be implemented in terms of the 32-bit atomicrmw by appropriately
manipulating the operands. There is no functional change for the handling of
partword or/xor, but the transformation for partword 'and' is new.
The advantage of performing this transformation early is that the same
code-path can be used regardless of the approach used to expand the atomicrmw
(AtomicExpansionKind). i.e. the same logic is used for
AtomicExpansionKind::CmpXchg and can also be used by the intrinsic-based
expansion in D47882.
Differential Revision: https://reviews.llvm.org/D48129
llvm-svn: 340027
Add support for cases where only some c1+c2 results exceed the max bitshift, clamping accordingly.
Differential Revision: https://reviews.llvm.org/D35722
llvm-svn: 340010
https://reviews.llvm.org/D50401
Add opcodes for llvm.intrinsic.trunc, round, and update the IRTranslator
for the same.
Reviewed by: dsanders.
llvm-svn: 339977
well as MIR parsing support for `MCSymbol` `MachineOperand`s.
The only real way to test pre- and post-instruction symbol support is to
use them in operands, so I ended up implementing that within the patch
as well. I can split out the operand support if folks really want but it
doesn't really seem worth it.
The functional implementation of pre- and post-instruction symbols is
now *completely trivial*. Two tiny bits of code in the (misnamed)
AsmPrinter. It should be completely target independent as well. We emit
these exactly the same way as we emit basic block labels. Most of the
code here is to give full dumping, MIR printing, and MIR parsing support
so that we can write useful tests.
The MIR parsing of MC symbol operands still isn't 100%, as it forces the
symbols to be non-temporary and non-local symbols with names. However,
those names often can encode most (if not all) of the special semantics
desired, and unnamed symbols seem especially annoying to serialize and
de-serialize. While this isn't perfect or full support, it seems plenty
to write tests that exercise usage of these kinds of operands.
The MIR support for pre-and post-instruction symbols was quite
straightforward. I chose to print them out in an as-if-operand syntax
similar to debug locations as this seemed the cleanest way and let me
use nice introducer tokens rather than inventing more magic punctuation
like we use for memoperands.
However, supporting MIR-based parsing of these symbols caused me to
change the design of the symbol support to allow setting arbitrary
symbols. Without this, I don't see any reasonable way to test things
with MIR.
Differential Revision: https://reviews.llvm.org/D50833
llvm-svn: 339962
When nodes are reassociated the vector-reduction flag gets lost.
The test case is here is what would happen if you had a sum of absolute differences loop that started with a non-zero but contant sum and that loop was unrolled. The vectorizer will generate a constant vector for the initial value. And DAGCombiner reassociate tries to move it down the addition tree erasing the vector-reduction flag. Interestingly this moves constants the opposite direction of the reassociate IR pass.
I've chosen to just punt on the reassociate, but I suppose we could maybe preserve the flag if both nodes have it set.
Differential Revision: https://reviews.llvm.org/D50827
llvm-svn: 339946
a generically extensible collection of extra info attached to
a `MachineInstr`.
The primary change here is cleaning up the APIs used for setting and
manipulating the `MachineMemOperand` pointer arrays so chat we can
change how they are allocated.
Then we introduce an extra info object that using the trailing object
pattern to attach some number of MMOs but also other extra info. The
design of this is specifically so that this extra info has a fixed
necessary cost (the header tracking what extra info is included) and
everything else can be tail allocated. This pattern works especially
well with a `BumpPtrAllocator` which we use here.
I've also added the basic scaffolding for putting interesting pointers
into this, namely pre- and post-instruction symbols. These aren't used
anywhere yet, they're just there to ensure I've actually gotten the data
structure types correct. I'll flesh out support for these in
a subsequent patch (MIR dumping, parsing, the works).
Finally, I've included an optimization where we store any single pointer
inline in the `MachineInstr` to avoid the allocation overhead. This is
expected to be the overwhelmingly most common case and so should avoid
any memory usage growth due to slightly less clever / dense allocation
when dealing with >1 MMO. This did require several ergonomic
improvements to the `PointerSumType` to reasonably support the various
usage models.
This also has a side effect of freeing up 8 bits within the
`MachineInstr` which could be repurposed for something else.
The suggested direction here came largely from Hal Finkel. I hope it was
worth it. ;] It does hopefully clear a path for subsequent extensions
w/o nearly as much leg work. Lots of thanks to Reid and Justin for
careful reviews and ideas about how to do all of this.
Differential Revision: https://reviews.llvm.org/D50701
llvm-svn: 339940
In cases where the debugger load time is a worthwhile tradeoff (or less
costly - such as loading from a DWP instead of a variety of DWOs
(possibly over a high-latency/distributed filesystem)) against object
file size, it can be reasonable to disable pubnames and corresponding
gdb-index creation in the linker.
A backend-flag version of this was implemented for NVPTX in
D44385/r327994 - which was fine for NVPTX which wouldn't mix-and-match
CUs. Now that it's going to be a user-facing option (likely powered by
"-gno-pubnames", the same as GCC) it should be encoded in the
DICompileUnit so it can vary per-CU.
After this, likely the NVPTX support should be migrated to the metadata
& the previous flag implementation should be removed.
Reviewers: aprantl
Differential Revision: https://reviews.llvm.org/D50213
llvm-svn: 339939
Each use of a value should be jointly dominated by the union of defs and
undefs. It can happen that it will only be jointly dominated by undefs,
and that is still legal. Make sure that the verifier is aware of that.
llvm-svn: 339924
There is no way in the universe, that doing a full-width division in
software will be faster than doing overflowing multiplication in
software in the first place, especially given that this same full-width
multiplication needs to be done anyway.
This patch replaces the previous implementation with a direct lowering
into an overflowing multiplication algorithm based on half-width
operations.
Correctness of the algorithm was verified by exhaustively checking the
output of this algorithm for overflowing multiplication of 16 bit
integers against an obviously correct widening multiplication. Baring
any oversights introduced by porting the algorithm to DAG, confidence in
correctness of this algorithm is extremely high.
Following table shows the change in both t = runtime and s = space. The
change is expressed as a multiplier of original, so anything under 1 is
“better” and anything above 1 is worse.
+-------+-----------+-----------+-------------+-------------+
| Arch | u64*u64 t | u64*u64 s | u128*u128 t | u128*u128 s |
+-------+-----------+-----------+-------------+-------------+
| X64 | - | - | ~0.5 | ~0.64 |
| i686 | ~0.5 | ~0.6666 | ~0.05 | ~0.9 |
| armv7 | - | ~0.75 | - | ~1.4 |
+-------+-----------+-----------+-------------+-------------+
Performance numbers have been collected by running overflowing
multiplication in a loop under `perf` on two x86_64 (one Intel Haswell,
other AMD Ryzen) based machines. Size numbers have been collected by
looking at the size of function containing an overflowing multiply in
a loop.
All in all, it can be seen that both performance and size has improved
except in the case of armv7 where code size has regressed for 128-bit
multiply. u128*u128 overflowing multiply on 32-bit platforms seem to
benefit from this change a lot, taking only 5% of the time compared to
original algorithm to calculate the same thing.
The final benefit of this change is that LLVM is now capable of lowering
the overflowing unsigned multiply for integers of any bit-width as long
as the target is capable of lowering regular multiplication for the same
bit-width. Previously, 128-bit overflowing multiply was the widest
possible.
Patch by Simonas Kazlauskas!
Differential Revision: https://reviews.llvm.org/D50310
llvm-svn: 339922
This patch refactors the existing TargetLowering::BuildSDIV base implementation to support non-uniform constant vector denominators.
This is the last patch necessary to close PR36545
Differential Revision: https://reviews.llvm.org/D50765
llvm-svn: 339908
This patch fixes PR38125.
Instruction extension types are recorded in PromotedInsts, it can be used later in function canGetThrough. If an instruction has two users with different extension types, it will be inserted into PromotedInsts two times in function promoteOperandForOther. The second one overwrites the first one, and the final extension type is wrong, later causes problem in canGetThrough.
This patch changes the simple bool extension type to 2-bit enum type, add a BothExtension type in addition to zero/sign extension. When an user sees BothExtension for an instruction, it actually knows nothing about how that instruction is extended.
Differential Revision: https://reviews.llvm.org/D49512
llvm-svn: 339822
