This is an initial patch to add the necessary support for a DemandedElts argument to SimplifyDemandedBits, more closely matching computeKnownBits and to help improve vector codegen.
I've added only a small amount of the changes necessary to get at least one test to update - a lot more can be done but I'd like to add these methodically with proper test coverage, at the same time the hope is to slowly move some/all of SimplifyDemandedVectorElts into SimplifyDemandedBits as well.
Differential Revision: https://reviews.llvm.org/D55768
llvm-svn: 349374
If a saturating add/sub has one constant operand, then we can
determine the possible range of outputs it can produce, and simplify
an icmp comparison based on that.
The implementation is based on a similar existing mechanism for
simplifying binary operator + icmps.
Differential Revision: https://reviews.llvm.org/D55735
llvm-svn: 349369
We keep a few iterators into the basic block we're selecting while
performing FastISel. Usually this is fine, but occasionally code wants
to remove already-emitted instructions. When this happens we have to be
careful to update those iterators so they're not pointint at dangling
memory.
llvm-svn: 349365
These features (fairly) recently got split out into their own feature, so we
should make CodeGen use them when available. The main change here is that the
check used to be based on the triple, but now it's based on CPU features.
llvm-svn: 349355
Class InstrBuilder wrongly assumed that llvm targets were always able to return
a non-null pointer when createMCInstrAnalysis() was called on them.
This was causing crashes when simulating executions for targets that don't
provide an MCInstrAnalysis object.
This patch fixes the issue by making MCInstrAnalysis optional.
llvm-svn: 349352
The Load/Store Optimizer runs before Machine Block Placement. At O3 the
Tail Duplication Threshold is set to 4 instructions and this can create
new opportunities for the Load/Store Optimizer. It seems worthwhile to
run it once again.
llvm-svn: 349338
GCC emitted these unconditionally on/before 4.4/March 2012
Clang emitted these unconditionally on/before 3.5/March 2014
This improves performance when parsing CUs (especially those using split
DWARF) that contain no code ranges (such as the mini CUs that may be
created by ThinLTO importing - though generally they should be/are
avoided, especially for Split DWARF because it produces a lot of very
small CUs, which don't scale well in a bunch of other ways too
(including size)).
llvm-svn: 349333
Appended options -ppc-vsr-nums-as-vr and -ppc-asm-full-reg-names to get the
more descriptive output. Also removed useless function attributes.
llvm-svn: 349329
With some patch adopted for Power9 vabsd* insns, some CHECKs can't get the expected results.
But it's false alarm, we should update the case more robust.
llvm-svn: 349325
I'd like to try to move a lot of the flag matching out of EmitTest and push it to isel or isel preprocessing. This is a step towards that.
The test-shrink-bug.ll changie is an improvement because we are no longer interfering with test shrink handling in isel.
The pr34137.ll change is a regression, but the IR came from -O0 and was not reduced by InstCombine. So it contains a lot of redundancies like duplicate loads that made it combine poorly.
llvm-svn: 349315
The transform performs a bitwise logic op in a wider type followed by
truncate when both inputs are truncated from the same source type:
logic_op (truncate x), (truncate y) --> truncate (logic_op x, y)
There are a bunch of other checks that should prevent doing this when
it might be harmful.
We already do this transform for scalars in this spot. The vector
limitation was shared with a check for the case when the operands are
extended. I'm not sure if that limit is needed either, but that would
be a separate patch.
Differential Revision: https://reviews.llvm.org/D55448
llvm-svn: 349303
Also exposes an issue in DAGCombiner::visitFunnelShift where we were assuming the shift amount had the result type (after legalization it'll have the targets shift amount type).
llvm-svn: 349298
Use consistent rules for when to lower to SHLD/SHRD for slow machines - fixes a weird issue where funnel shift gets expanded but then X86ISelLowering's combineOr sees the optsize and combines to SHLD/SHRD, but now with the modulo amount guard......
llvm-svn: 349285
Summary:
Make machine PHIs optimization to work for single value register taken from
several different copies. This is the first step to fix PR38917. This change
allows to get rid of redundant PHIs (see opt_phis2.mir test) to make
the subsequent optimizations (like CSE) possible and simpler.
For instance, before this patch the code like this:
%b = COPY %z
...
%a = PHI %bb1, %a; %bb2, %b
could be optimized to:
%a = %b
but the code like this:
%c = COPY %z
...
%b = COPY %z
...
%a = PHI %bb1, %a; %bb2, %b; %bb3, %c
would remain unchanged.
With this patch the latter case will be optimized:
%a = %z```.
Committed on behalf of: Anton Afanasyev anton.a.afanasyev@gmail.com
Reviewers: RKSimon, MatzeB
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D54839
llvm-svn: 349271
If a saturating add/sub with a constant operand is compared to
another constant, we should be able to determine that the condition
is always true/false in some cases (but currently don't).
llvm-svn: 349261
Add an original test case for setb before the exploitation actually takes effect, later we can check the difference.
Differential Revision: https://reviews.llvm.org/D55696
llvm-svn: 349251
Summary:
This patch checks if the section order is correct when reading a wasm
object file in `WasmObjectFile` and converting YAML to wasm object in
yaml2wasm. (It is not possible to check when reading YAML because it is
handled exclusively by the YAML reader.)
This checks the ordering of all known sections (core sections + known
custom sections). This also adds section ID DataCount section that will
be scheduled to be added in near future.
Reviewers: sbc100
Subscribers: dschuff, mgorny, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54924
llvm-svn: 349221
The current code relies on LeaderUseCount to determine if we can remove
an SSA copy, but in that the LeaderUseCount does not refer to the SSA
copy. If a SSA copy is a dominating leader, we use the operand as dominating
leader instead. This means we removed a user of a ssa copy and we should
decrement its use count, so we can remove the ssa copy once it becomes dead.
Fixes PR38804.
Reviewers: efriedma, davide
Reviewed By: davide
Differential Revision: https://reviews.llvm.org/D51595
llvm-svn: 349217
When converting dbg.declares, if the described value is a [s|z]ext,
refer to the ext directly instead of referring to its operand.
This fixes a narrowing bug (the debugger got the sign of a variable
wrong, see llvm.org/PR35400).
The main reason to refer to the ext's operand was that an optimization
may remove the ext itself, leading to a dropped variable. Now that
InstCombine has been taught to use replaceAllDbgUsesWith (r336451), this
is less of a concern. Other passes can/should adopt this API as needed
to fix dropped variable bugs.
Differential Revision: https://reviews.llvm.org/D51813
llvm-svn: 349214
The change is an effort to split and refactor abandoned
D34708 into smaller parts.
Here the behaviour of unsupported instructions is changed
to match the behaviour of explicit intrinsics calls.
Currently LLVM crashes with:
> Assertion getInstruction() && "Not a call or invoke instruction!" failed.
With this patch LLVM produces a more sensible error message:
> Cannot select: ... i32 = ExternalSymbol'__foobar'
Author: Denys Zariaiev <denys.zariaiev@gmail.com>
Differential Revision: https://reviews.llvm.org/D55145
llvm-svn: 349213
In ThinLTO many split CUs may be effectively empty because of the lack
of support for cross-unit references in split DWARF.
Using a split unit in those cases is just a waste/overhead - and turned
out to be one contributor to a significant symbolizer performance issue
when global variable debug info was being imported (see r348416 for the
primary fix) due to symbolizers seeing CUs with no ranges, assuming
there might still be addresses covered and walking into the split CU to
see if there are any ranges (when that split CU was in a DWP file, that
meant loading the DWP and its index, the index was extra large because
of all these fractured/empty CUs... and so was very expensive to load).
(the 3rd fix which will follow, is to assume that a CU with no ranges is
empty rather than merely missing its CU level range data - and to not
walk into its DIEs (split or otherwise) in search of address information
that is generally not present)
llvm-svn: 349207
Optimization transformations are intentionally disabled by the 'optnone'
function attribute. Therefore do not warn if transformation metadata is
still present.
Using the legacy pass manager structure, the `skipFunction` method takes
care for the optnone attribute (already called before this patch). For
the new pass manager, there is no equivalent, so we check for the
'optnone' attribute manually.
Differential Revision: https://reviews.llvm.org/D55690
llvm-svn: 349184
