This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300
We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.
We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.
A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.
In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect
Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324
llvm-svn: 371635
Summary:
This catches malformed mir files which specify alignment as log2 instead of pow2.
See https://reviews.llvm.org/D65945 for reference,
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790
Reviewers: courbet
Subscribers: MatzeB, qcolombet, dschuff, arsenm, sdardis, nemanjai, jvesely, nhaehnle, hiraditya, kbarton, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Petar.Avramovic, asbirlea, s.egerton, pzheng, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67433
llvm-svn: 371608
This reverts commit r371584. It introduced a dependency from compiler-rt
to llvm/include/ADT, which is problematic for multiple reasons.
One is that it is a novel dependency edge, which needs cross-compliation
machinery for llvm/include/ADT (yes, it is true that right now
compiler-rt included only header-only libraries, however, if we allow
compiler-rt to depend on anything from ADT, other libraries will
eventually get used).
Secondly, depending on ADT from compiler-rt exposes ADT symbols from
compiler-rt, which would cause ODR violations when Clang is built with
the profile library.
llvm-svn: 371598
This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300
We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.
We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.
A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.
In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect
Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324
llvm-svn: 371584
Summary:
This commit is the final one for adding tapi support to the llvm-nm implementation.
This commit also has accompanying tests the additions to lib/Object
Reviewers: ributzka, steven_wu
Reviewed By: ributzka
Subscribers: hiraditya, plotfi, dexonsmith, rupprecht, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66160
llvm-svn: 371576
This fixes a crash in tail call translation caused by assume and lifetime_end
intrinsics.
It's possible to have instructions other than a return after a tail call which
will still have `Analysis::isInTailCallPosition` return true. (Namely,
lifetime_end and assume intrinsics.)
If we emit a tail call, we should stop translating instructions in the block.
Otherwise, we can end up emitting an extra return, or dead instructions in
general. This makes the verifier unhappy, and is generally unfortunate for
codegen.
This also removes the code from AArch64CallLowering that checks if we have a
tail call when lowering a return. This is covered by the new code now.
Also update call-translator-tail-call.ll to show that we now properly tail call
in the presence of lifetime_end and assume.
Differential Revision: https://reviews.llvm.org/D67415
llvm-svn: 371572
Add support for sibcalling calls whose calling convention differs from the
caller's.
- Port over `CCState::resultsCombatible` from CallingConvLower.cpp into
CallLowering. This is used to verify that the way the caller and callee CC
handle incoming arguments matches up.
- Add `CallLowering::analyzeCallResult`. This is basically a port of
`CCState::AnalyzeCallResult`, but using `ArgInfo` rather than `ISD::InputArg`.
- Add `AArch64CallLowering::doCallerAndCalleePassArgsTheSameWay`. This checks
that the calling conventions are compatible, and that the caller and callee
preserve the same registers.
For testing:
- Update call-translator-tail-call.ll to show that we can now handle this.
- Add a GISel line to tailcall-ccmismatch.ll to show that we will not tail call
when the regmasks don't line up.
Differential Revision: https://reviews.llvm.org/D67361
llvm-svn: 371570
Expose a utility function so that all places which want to suppress speculation (when otherwise legal) due to ordering and/or sanitizer interaction can do so.
llvm-svn: 371556
This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300
We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.
We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.
A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.
In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect
Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324
llvm-svn: 371484
This is the first patch in a large sequence. The eventual goal is to have unordered atomic loads and stores - and possibly ordered atomics as well - handled through the normal ISEL codepaths for loads and stores. Today, there handled w/instances of AtomicSDNodes. The result of which is that all transforms need to be duplicated to work for unordered atomics. The benefit of the current design is that it's harder to introduce a silent miscompile by adding an transform which forgets about atomicity. See the thread on llvm-dev titled "FYI: proposed changes to atomic load/store in SelectionDAG" for further context.
Note that this patch is NFC unless the experimental flag is set.
The basic strategy I plan on taking is:
introduce infrastructure and a flag for testing (this patch)
Audit uses of isVolatile, and apply isAtomic conservatively*
piecemeal conservative* update generic code and x86 backedge code in individual reviews w/tests for cases which didn't check volatile, but can be found with inspection
flip the flag at the end (with minimal diffs)
Work through todo list identified in (2) and (3) exposing performance ops
(*) The "conservative" bit here is aimed at minimizing the number of diffs involved in (4). Ideally, there'd be none. In practice, getting it down to something reviewable by a human is the actual goal. Note that there are (currently) no paths which produce LoadSDNode or StoreSDNode with atomic MMOs, so we don't need to worry about preserving any behaviour there.
We've taken a very similar strategy twice before with success - once at IR level, and once at the MI level (post ISEL).
Differential Revision: https://reviews.llvm.org/D66309
llvm-svn: 371441
The bitstream remark serializer landed in r367372.
This adds a bitstream remark parser that parser bitstream remark files
to llvm::remarks::Remark objects through the RemarkParser interface.
A few interesting things to point out:
* There are parsing helpers to parse the different types of blocks
* The main parsing helper allows us to parse remark metadata and open an
external file containing the encoded remarks
* This adds a dependency from the Remarks library to the BitstreamReader
library
* The testing strategy is to create a remark entry through YAML, parse
it, serialize it to bitstream, parse that back and compare the objects.
* There are close to no tests for malformed bitstream remarks, due to
the lack of textual format for the bitstream format.
* This adds a new C API for parsing bitstream remarks:
LLVMRemarkParserCreateBitstream.
* This bumps the REMARKS_API_VERSION to 1.
Differential Revision: https://reviews.llvm.org/D67134
llvm-svn: 371429
Reapply with fix to reduce resources required by the compiler - use
unsigned[2] instead of std::pair. This causes clang and gcc to compile
the generated file multiple times faster, and hopefully will reduce
the resource requirements on Visual Studio also. This fix is a little
ugly but it's clearly the same issue the previous author of
DFAPacketizer faced (the previous tables use unsigned[2] rather uglily
too).
This patch allows the DFAPacketizer to be queried after a packet is formed to work out which
resources were allocated to the packetized instructions.
This is particularly important for targets that do their own bundle packing - it's not
sufficient to know simply that instructions can share a packet; which slots are used is
also required for encoding.
This extends the emitter to emit a side-table containing resource usage diffs for each
state transition. The packetizer maintains a set of all possible resource states in its
current state. After packetization is complete, all remaining resource states are
possible packetization strategies.
The sidetable is only ~500K for Hexagon, but the extra tracking is disabled by default
(most uses of the packetizer like MachinePipeliner don't care and don't need the extra
maintained state).
Differential Revision: https://reviews.llvm.org/D66936
llvm-svn: 371399
This patch allows the DFAPacketizer to be queried after a packet is formed to work out which
resources were allocated to the packetized instructions.
This is particularly important for targets that do their own bundle packing - it's not
sufficient to know simply that instructions can share a packet; which slots are used is
also required for encoding.
This extends the emitter to emit a side-table containing resource usage diffs for each
state transition. The packetizer maintains a set of all possible resource states in its
current state. After packetization is complete, all remaining resource states are
possible packetization strategies.
The sidetable is only ~500K for Hexagon, but the extra tracking is disabled by default
(most uses of the packetizer like MachinePipeliner don't care and don't need the extra
maintained state).
Differential Revision: https://reviews.llvm.org/D66936
........
Reverted as this is causing "compiler out of heap space" errors on MSVC 2017/19 NDEBUG builds
llvm-svn: 371393
Summary:
This patch implements two arithmetic intrinsics:
* int_aarch64_sve_abs
* int_aarch64_sve_neg
testing the support for scalable vector types in intrinsics added in D65930.
Reviewed By: greened
Differential Revision: https://reviews.llvm.org/D65931
llvm-svn: 371388
Loosely based on DAGCombiner version, but this part is slightly simpler in
GlobalIsel because all address calculation is performed by G_GEP. That makes
the inc/dec distinction moot so there's just pre/post to think about.
No targets can handle it yet so testing is via a special flag that overrides
target hooks.
llvm-svn: 371384
Summary:
This changes the ParamLoadedValue pair which the describeLoadedValue()
hook returns so that MachineOperand objects are returned instead of
pointers.
When describing call site values we may need to describe operands which
are not part of the instruction. One such example is zero-materializing
XORs on x86, which I have implemented support for in a child revision.
Instead of having to return a pointer to an operand stored somewhere
outside the instruction, start returning objects directly instead, as
that simplifies the code.
The MachineOperand class only holds POD members, and on x86-64 it is 32
bytes large. That combined with copy elision means that the overhead of
returning a machine operand object from the hook does not become very
large.
I benchmarked this on a 8-thread i7-8650U machine with 32 GB RAM. The
benchmark consisted of building a clang 8.0 binary configured with:
-DCMAKE_BUILD_TYPE=RelWithDebInfo \
-DLLVM_TARGETS_TO_BUILD=X86 \
-DLLVM_USE_SANITIZER=Address \
-DCMAKE_CXX_FLAGS="-Xclang -femit-debug-entry-values -stdlib=libc++"
The average wall clock time increased by 4 seconds, from 62:05 to
62:09, which is an 0.1% increase.
Reviewers: aprantl, vsk, djtodoro, NikolaPrica
Reviewed By: vsk
Subscribers: hiraditya, ychen, llvm-commits
Tags: #debug-info, #llvm
Differential Revision: https://reviews.llvm.org/D67261
llvm-svn: 371332
This patch enables generation of fused multiply add/sub for instructions operating on fp16.
Tested on aarch64-linux.
Differential Revision: https://reviews.llvm.org/D67297
llvm-svn: 371321
Summary:
Add an intrinsic that takes 2 unsigned integers with
the scale of them provided as the third argument and
performs fixed point multiplication on them. The
result is saturated and clamped between the largest and
smallest representable values of the first 2 operands.
This is a part of implementing fixed point arithmetic
in clang where some of the more complex operations
will be implemented as intrinsics.
Patch by: leonardchan, bjope
Reviewers: RKSimon, craig.topper, bevinh, leonardchan, lebedev.ri, spatel
Reviewed By: leonardchan
Subscribers: ychen, wuzish, nemanjai, MaskRay, jsji, jdoerfert, Ka-Ka, hiraditya, rjmccall, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57836
llvm-svn: 371308
Summary:
This patch introduces initial `AAValueSimplify` which simplifies a value in a context.
example
- (for function returned) If all the return values are the same and constant, then we can replace callsite returned with the constant.
- If an internal function takes the same value(constant) as an argument in the callsite, then we can replace the argument with that constant.
Reviewers: jdoerfert, sstefan1
Reviewed By: jdoerfert
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66967
llvm-svn: 371291
Summary:
This is the first change to enable the TLI to be built per-function so
that -fno-builtin* handling can be migrated to use function attributes.
See discussion on D61634 for background. This is an enabler for fixing
handling of these options for LTO, for example.
This change should not affect behavior, as the provided function is not
yet used to build a specifically per-function TLI, but rather enables
that migration.
Most of the changes were very mechanical, e.g. passing a Function to the
legacy analysis pass's getTLI interface, or in Module level cases,
adding a callback. This is similar to the way the per-function TTI
analysis works.
There was one place where we were looking for builtins but not in the
context of a specific function. See FindCXAAtExit in
lib/Transforms/IPO/GlobalOpt.cpp. I'm somewhat concerned my workaround
could provide the wrong behavior in some corner cases. Suggestions
welcome.
Reviewers: chandlerc, hfinkel
Subscribers: arsenm, dschuff, jvesely, nhaehnle, mehdi_amini, javed.absar, sbc100, jgravelle-google, eraman, aheejin, steven_wu, george.burgess.iv, dexonsmith, jfb, asbirlea, gchatelet, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66428
llvm-svn: 371284
version after r371273.
Also fix a minor issue in r371273 that only surfaced after template
instantiation from LLVM's use of the demangler.
llvm-svn: 371274
Add the new method `LibCallSimplifier::substituteInParent()` that calls
`LibCallSimplifier::replaceAllUsesWith()' and
`LibCallSimplifier::eraseFromParent()` back to back, simplifying the
resulting code.
llvm-svn: 371264
Summary:
There's an unspoken invariant of callbr that the list of BlockAddress
Constants in the "function args" list match the BasicBlocks in the
"other labels" list. (This invariant is being added to the LangRef in
https://reviews.llvm.org/D67196).
When modifying the any of the indirect destinations of a callbr
instruction (possible jump targets), we need to update the function
arguments if the argument is a BlockAddress whose BasicBlock refers to
the indirect destination BasicBlock being replaced. Otherwise, many
transforms that modify successors will end up violating that invariant.
A recent change to the arm64 Linux kernel exposed this bug, which
prevents the kernel from booting.
I considered maintaining a mapping from indirect destination BasicBlock
to argument operand BlockAddress, but this ends up being a one to
potentially many (though usually one) mapping. Also, the list of
arguments to a function (or more typically inline assembly) ends up
being less than 10. The implementation is significantly simpler to just
rescan the full list of arguments. Because of the one to potentially
many relationship, the full arg list must be scanned (we can't stop at
the first instance).
Thanks to the following folks that reported the issue and helped debug
it:
* Nathan Chancellor
* Will Deacon
* Andrew Murray
* Craig Topper
Link: https://bugs.llvm.org/show_bug.cgi?id=43222
Link: https://github.com/ClangBuiltLinux/linux/issues/649
Link: https://lists.infradead.org/pipermail/linux-arm-kernel/2019-September/678330.html
Reviewers: craig.topper, chandlerc
Reviewed By: craig.topper
Subscribers: void, javed.absar, kristof.beyls, hiraditya, llvm-commits, nathanchance, srhines
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67252
llvm-svn: 371262
ORC-RPC batches calls by default, and the channel's send method must be called
to transfer any buffered calls to the remote. The call to send was missing on
responses and blocking calls in the SingleThreadedRPCEndpoint. This patch adds
the necessary calls and modifies the RPC unit test to check for them.
llvm-svn: 371245
The IRBuilder doesn't know that the two floating point to integer instructions
have constrained equivalents. This patch adds the support by building on
the strict FP mode now present in the IRBuilder.
Reviewed by: John McCall
Approved by: John McCall
Differential Revision: https://reviews.llvm.org/D67291
llvm-svn: 371235
In order to keep remarks around, we need to make them tied to a string
table.
Users then can delete the parser and rely on the string table to keep
the memory of the strings alive and deduplicated.
llvm-svn: 371233
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790
Reviewers: courbet
Subscribers: nemanjai, javed.absar, hiraditya, kbarton, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, s.egerton, pzheng, ychen, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67267
llvm-svn: 371212
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790
Reviewers: courbet
Subscribers: jyknight, sdardis, nemanjai, javed.absar, hiraditya, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, s.egerton, pzheng, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67229
llvm-svn: 371200
This patch allows the DFAPacketizer to be queried after a packet is formed to work out which
resources were allocated to the packetized instructions.
This is particularly important for targets that do their own bundle packing - it's not
sufficient to know simply that instructions can share a packet; which slots are used is
also required for encoding.
This extends the emitter to emit a side-table containing resource usage diffs for each
state transition. The packetizer maintains a set of all possible resource states in its
current state. After packetization is complete, all remaining resource states are
possible packetization strategies.
The sidetable is only ~500K for Hexagon, but the extra tracking is disabled by default
(most uses of the packetizer like MachinePipeliner don't care and don't need the extra
maintained state).
Differential Revision: https://reviews.llvm.org/D66936
llvm-svn: 371198
Summary:
This fixes poor scheduling in a function containing a barrier and a few
load instructions.
Without this fix, ScheduleDAGInstrs::buildSchedGraph adds an artificial
edge in the dependency graph from the barrier instruction to the exit
node representing live-out latency, with a latency of about 500 cycles.
Because of this it thinks the critical path through the graph also has
a latency of about 500 cycles. And because of that it does not think
that any of the load instructions are on the critical path, so it
schedules them with no regard for their (80 cycle) latency, which gives
poor results.
Reviewers: arsenm, dstuttard, tpr, nhaehnle
Subscribers: kzhuravl, jvesely, wdng, yaxunl, t-tye, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67218
llvm-svn: 371192
`struct Elf*_Shdr` has a field `sh_offset`, named `ShOffset` in
llvm::ELFYAML::Section. Rename SHOffset (e_shoff) to SHOff to prevent confusion.
Reviewed By: grimar
Differential Revision: https://reviews.llvm.org/D67254
llvm-svn: 371185
The MVE and LOB extensions of Armv8.1m can be combined to enable
'tail predication' which removes the need for a scalar remainder
loop after vectorization. Lane predication is performed implicitly
via a system register. The effects of predication is described in
Section B5.6.3 of the Armv8.1-m Arch Reference Manual, the key points
being:
- For vector operations that perform reduction across the vector and
produce a scalar result, whether the value is accumulated or not.
- For non-load instructions, the predicate flags determine if the
destination register byte is updated with the new value or if the
previous value is preserved.
- For vector store instructions, whether the store occurs or not.
- For vector load instructions, whether the value that is loaded or
whether zeros are written to that element of the destination
register.
This patch implements a pass that takes a hardware loop, containing
masked vector instructions, and converts it something that resembles
an MVE tail predicated loop. Currently, if we had code generation,
we'd generate a loop in which the VCTP would generate the predicate
and VPST would then setup the value of VPR.PO. The loads and stores
would be placed in VPT blocks so this is not tail predication, but
normal VPT predication with the predicate based upon a element
counting induction variable. Further work needs to be done to finally
produce a true tail predicated loop.
Because only the loads and stores are predicated, in both the LLVM IR
and MIR level, we will restrict support to only lane-wise operations
(no horizontal reductions). We will perform a final check on MIR
during loop finalisation too.
Another restriction, specific to MVE, is that all the vector
instructions need operate on the same number of elements. This is
because predication is performed at the byte level and this is set
on entry to the loop, or by the VCTP instead.
Differential Revision: https://reviews.llvm.org/D65884
llvm-svn: 371179
Properly check if NewAAInfo conflicts with AAInfo.
Update local variable and alias set that a change occured when a conflict is found.
Resolves PR42969.
llvm-svn: 371139
This patch reuses the MIR vreg renamer from the MIRCanonicalizerPass to cleanup
names of vregs in a MIR file for MIR test authors. I found it useful when
writing a regression test for a globalisel failure I encountered recently and
thought it might be useful for other folks as well.
Differential Revision: https://reviews.llvm.org/D67209
llvm-svn: 371121
Recommit basic sibling call lowering (https://reviews.llvm.org/D67189)
The issue was that if you have a return type other than void, call lowering
will emit COPYs to get the return value after the call.
Disallow sibling calls other than ones that return void for now. Also
proactively disable swifterror tail calls for now, since there's a similar issue
with COPYs there.
Update call-translator-tail-call.ll to include test cases for each of these
things.
llvm-svn: 371114
Summary:
This is a simple change that allows easy iterator semantics for symbols held in interface file.
Not being used, so harmless change right now, but will be once TBD-v4 is submitted.
Reviewers: ributzka, steven_wu
Reviewed By: ributzka
Subscribers: javed.absar, kristof.beyls, dexonsmith, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67204
llvm-svn: 371097
If we have:
bb5:
br i1 %arg3, label %bb6, label %bb7
bb6:
%tmp = getelementptr inbounds i32, i32* %arg1, i64 2
store i32 3, i32* %tmp, align 4
br label %bb9
bb7:
%tmp8 = getelementptr inbounds i32, i32* %arg1, i64 2
store i32 3, i32* %tmp8, align 4
br label %bb9
bb9: ; preds = %bb4, %bb6, %bb7
...
We can't sink stores directly into bb9.
This patch creates new BB that is successor of %bb6 and %bb7
and sinks stores into that block.
SplitFooterBB is the parameter to the pass that controls
that behavior.
Change-Id: I7fdf50a772b84633e4b1b860e905bf7e3e29940f
Differential: https://reviews.llvm.org/D66234
llvm-svn: 371089
This adds support for basic sibling call lowering in AArch64. The intent here is
to only handle tail calls which do not change the ABI (hence, sibling calls.)
At this point, it is very restricted. It does not handle
- Vararg calls.
- Calls with outgoing arguments.
- Calls whose calling conventions differ from the caller's calling convention.
- Tail/sibling calls with BTI enabled.
This patch adds
- `AArch64CallLowering::isEligibleForTailCallOptimization`, which is equivalent
to the same function in AArch64ISelLowering.cpp (albeit with the restrictions
above.)
- `mayTailCallThisCC` and `canGuaranteeTCO`, which are identical to those in
AArch64ISelLowering.cpp.
- `getCallOpcode`, which is exactly what it sounds like.
Tail/sibling calls are lowered by checking if they pass target-independent tail
call positioning checks, and checking if they satisfy
`isEligibleForTailCallOptimization`. If they do, then a tail call instruction is
emitted instead of a normal call. If we have a sibling call (which is always the
case in this patch), then we do not emit any stack adjustment operations. When
we go to lower a return, we check if we've already emitted a tail call. If so,
then we skip the return lowering.
For testing, this patch
- Adds call-translator-tail-call.ll to test which tail calls we currently lower,
which ones we don't, and which ones we shouldn't.
- Updates branch-target-enforcement-indirect-calls.ll to show that we fall back
as expected.
Differential Revision: https://reviews.llvm.org/D67189
........
This fails on EXPENSIVE_CHECKS builds due to a -verify-machineinstrs test failure in CodeGen/AArch64/dllimport.ll
llvm-svn: 371051
Summary:
This patch renames functions that takes or returns alignment as log2, this patch will help with the transition to llvm::Align.
The renaming makes it explicit that we deal with log(alignment) instead of a power of two alignment.
A few renames uncovered dubious assignments:
- `MirParser`/`MirPrinter` was expecting powers of two but `MachineFunction` and `MachineBasicBlock` were using deal with log2(align). This patch fixes it and updates the documentation.
- `MachineBlockPlacement` exposes two flags (`align-all-blocks` and `align-all-nofallthru-blocks`) supposedly interpreted as power of two alignments, internally these values are interpreted as log2(align). This patch updates the documentation,
- `MachineFunctionexposes` exposes `align-all-functions` also interpreted as power of two alignment, internally this value is interpreted as log2(align). This patch updates the documentation,
Reviewers: lattner, thegameg, courbet
Subscribers: dschuff, arsenm, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, javed.absar, hiraditya, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, jocewei, jsji, Jim, s.egerton, llvm-commits, courbet
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65945
llvm-svn: 371045
As DW_AT_rnglists_base points after the header and headers have
different sizes for DWARF32 and DWARF64, we have to use the format
of the CU to adjust the offset correctly in order to extract
the referenced range list table.
The patch also changes the type of RangeSectionBase because in DWARF64
it is 8-bytes long.
Differential Revision: https://reviews.llvm.org/D67098
llvm-svn: 371016
This adds support for basic sibling call lowering in AArch64. The intent here is
to only handle tail calls which do not change the ABI (hence, sibling calls.)
At this point, it is very restricted. It does not handle
- Vararg calls.
- Calls with outgoing arguments.
- Calls whose calling conventions differ from the caller's calling convention.
- Tail/sibling calls with BTI enabled.
This patch adds
- `AArch64CallLowering::isEligibleForTailCallOptimization`, which is equivalent
to the same function in AArch64ISelLowering.cpp (albeit with the restrictions
above.)
- `mayTailCallThisCC` and `canGuaranteeTCO`, which are identical to those in
AArch64ISelLowering.cpp.
- `getCallOpcode`, which is exactly what it sounds like.
Tail/sibling calls are lowered by checking if they pass target-independent tail
call positioning checks, and checking if they satisfy
`isEligibleForTailCallOptimization`. If they do, then a tail call instruction is
emitted instead of a normal call. If we have a sibling call (which is always the
case in this patch), then we do not emit any stack adjustment operations. When
we go to lower a return, we check if we've already emitted a tail call. If so,
then we skip the return lowering.
For testing, this patch
- Adds call-translator-tail-call.ll to test which tail calls we currently lower,
which ones we don't, and which ones we shouldn't.
- Updates branch-target-enforcement-indirect-calls.ll to show that we fall back
as expected.
Differential Revision: https://reviews.llvm.org/D67189
llvm-svn: 370996
In mingw environments, resources are normally compiled to resource
object files directly, instead of letting the linker convert them to
COFF format.
Since some time, GCC supports the notion of a default manifest object.
When invoking the linker, GCC looks for the default manifest object
file, and if found in the expected path, it is added to linker commands.
The default manifest is one that indicates support for the latest known
versions of windows, to implicitly unlock the modern behaviours of certain
APIs.
Not all mingw/gcc distributions include this file, but e.g. in msys2,
the default manifest object is distributed in a separate package (which
can be but might not always be installed).
This means that even if user projects only use one single resource
object file, the linker can end up with two resource object files,
and thus needs to support merging them.
The default manifest has a language id of zero, and GNU ld has got
logic for dropping a manifest with a zero language id, if there's
another manifest present with a nonzero language id. If there are
multiple manifests with a nonzero language id, the merging process
errors out.
Differential Revision: https://reviews.llvm.org/D66825
llvm-svn: 370974
This patch merges the sancov module and funciton passes into one module pass.
The reason for this is because we ran into an out of memory error when
attempting to run asan fuzzer on some protobufs (pc.cc files). I traced the OOM
error to the destructor of SanitizerCoverage where we only call
appendTo[Compiler]Used which calls appendToUsedList. I'm not sure where precisely
in appendToUsedList causes the OOM, but I am able to confirm that it's calling
this function *repeatedly* that causes the OOM. (I hacked sancov a bit such that
I can still create and destroy a new sancov on every function run, but only call
appendToUsedList after all functions in the module have finished. This passes, but
when I make it such that appendToUsedList is called on every sancov destruction,
we hit OOM.)
I don't think the OOM is from just adding to the SmallSet and SmallVector inside
appendToUsedList since in either case for a given module, they'll have the same
max size. I suspect that when the existing llvm.compiler.used global is erased,
the memory behind it isn't freed. I could be wrong on this though.
This patch works around the OOM issue by just calling appendToUsedList at the
end of every module run instead of function run. The same amount of constants
still get added to llvm.compiler.used, abd we make the pass usage and logic
simpler by not having any inter-pass dependencies.
Differential Revision: https://reviews.llvm.org/D66988
llvm-svn: 370971
Summary:
- `__wasm_init_memory` is now the WebAssembly start function instead
of being called from `__wasm_call_ctors` or called directly by the
runtime.
- Adds a new synthetic data symbol `__wasm_init_memory_flag` that is
atomically incremented from zero to one by the thread responsible
for initializing memory.
- All threads now unconditionally perform data.drop on all passive
segments.
- Removes --passive-segments and --active-segments flags and controls
segment type based on --shared-memory instead. The deleted flags
were only present to ameliorate the upgrade path in Emscripten.
Reviewers: sbc100, aheejin
Subscribers: dschuff, jgravelle-google, sunfish, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65783
llvm-svn: 370965
This patch adds the ability to encode and decode InlineInfo objects and adds test coverage. Error handling is introduced in the encoding and decoding which will be used from here on out for remaining patches.
Differential Revision: https://reviews.llvm.org/D66600
llvm-svn: 370936
Summary:
Instead of building attributes for internal functions which we do not
update as long as we assume they are dead, we now do not create
attributes until we assume the internal function to be live. This
improves the number of required iterations, as well as the number of
required updates, in real code. On our tests, the results are mixed.
Reviewers: sstefan1, uenoku
Subscribers: hiraditya, bollu, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66914
llvm-svn: 370924
Summary:
We create attributes on-demand so we need to check the white list
on-demand. This also unifies the location at which we create,
initialize, and eventually invalidate new abstract attributes.
The tests show mixed results, a few more call site attributes are
determined which can cause more iterations.
Reviewers: uenoku, sstefan1
Subscribers: hiraditya, bollu, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66913
llvm-svn: 370922
Summary:
Before we tried to rule out non-exact definitions early but that lead to
on-demand attributes created for them anyway. As a consequence we needed
to look at the definition in the initialize of each attribute again.
This patch centralized this lookup and tightens the condition under
which we give up on non-exact definitions.
Reviewers: uenoku, sstefan1
Subscribers: hiraditya, bollu, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67115
llvm-svn: 370917
As commented on D65712, the getIRPosition methods weren't correctly being overridden.
Differential Revision: https://reviews.llvm.org/D67170
llvm-svn: 370914
This is the beginnings of a reimplementation of ModuloScheduleExpander. It works
by generating a single-block correct pipelined kernel and then peeling out the
prolog and epilogs.
This patch implements kernel generation as well as a validator that will
confirm the number of phis added is the same as the ModuloScheduleExpander.
Prolog and epilog peeling will come in a different patch.
Differential Revision: https://reviews.llvm.org/D67081
llvm-svn: 370893
Breaks BUILD_SHARED_LIBS build, introduces cycles in library dependency
graphs. (clangInterp depends on clangAST which depends on clangInterp)
This reverts r370839, which is an yet another recommit of D64146.
llvm-svn: 370874
Summary:
While fixing the handling of some error cases, r370363 introduced new
problems -- assertion failures due to unchecked errors (my excuse is that a very
early version of that patch used Optional<T> instead of Expected).
This patch adds proper handling of parsing errors encountered when
dumping location lists from inside DWARF DIEs, and adds a bunch of
additional tests.
I reorder the arguments of the location list dumping functions to make
them consistent, and also be able to dump the two kinds of location
lists generically.
Reviewers: JDevlieghere, dblaikie, probinson
Subscribers: aprantl, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67102
llvm-svn: 370868
Summary:
This patch introduces the skeleton of the constexpr interpreter,
capable of evaluating a simple constexpr functions consisting of
if statements. The interpreter is described in more detail in the
RFC. Further patches will add more features.
Reviewers: Bigcheese, jfb, rsmith
Subscribers: bruno, uenoku, ldionne, Tyker, thegameg, tschuett, dexonsmith, mgorny, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D64146
llvm-svn: 370839
The check needs to validate a counter offset before performing pointer
arithmetic with the (potentially corrupt) offset.
Found by UBSan's pointer overflow check.
rdar://54843625
Differential Revision: https://reviews.llvm.org/D66979
llvm-svn: 370826
On AArch64, s128 types have to be split into s64 GPRs when passed as arguments.
This change adds the generic support in call lowering for dealing with multiple
registers, for incoming and outgoing args.
Support for splitting for return types not yet implemented.
Differential Revision: https://reviews.llvm.org/D66180
llvm-svn: 370822
Add the no-capture argument attribute deduction to the Attributor
fixpoint framework.
The new string attributed "no-capture-maybe-returned" is introduced to
allow deduction of no-capture through functions that "capture" an
argument but only by "returning" it. It is only used by the Attributor
for testing.
Differential Revision: https://reviews.llvm.org/D59922
llvm-svn: 370817
This extends the existing logic for propagating constant expressions in an analogous manner for what we do across basic blocks. The core point is that we chose some order of operands, and canonicalize uses towards that one.
The heuristic used is inspired by the one used across blocks; in a follow up change, I'd plan to common them so that the cross block version uses the slightly stronger ordering herein.
As noted by the TODOs in the code, there's a good amount of room for improving the existing code and making it more powerful. Some follow up work planned.
Differential Revision: https://reviews.llvm.org/D66977
llvm-svn: 370791
Summary:
Fold-tail currently supports reduction last-vector-value live-out's,
but has yet to support last-scalar-value live-outs, including
non-header phi's. As it relies on AllowedExit in order to detect
them and bail out we need to add the non-header PHI nodes to
AllowedExit, otherwise we end up with miscompiles.
Solves https://bugs.llvm.org/show_bug.cgi?id=43166
Reviewers: fhahn, Ayal
Reviewed By: fhahn, Ayal
Subscribers: anna, hiraditya, rkruppe, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67074
llvm-svn: 370721
Emitting a schedule is really hard. There are lots of corner cases to take care of; in fact, of the 60+ SWP-specific testcases in the Hexagon backend most of those are testing codegen rather than the schedule creation itself.
One issue is that to test an emission corner case we must craft an input such that the generated schedule uses that corner case; sometimes this is very hard and convolutes testcases. Other times it is impossible but we want to test it anyway.
This patch adds a simple test pass that will consume a module containing a loop and generate pipelined code from it. We use post-instr-symbols as a way to annotate instructions with the stage and cycle that we want to schedule them at.
We also provide a flag that causes the MachinePipeliner to generate these annotations instead of actually emitting code; this allows us to generate an input testcase with:
llc < %s -stop-after=pipeliner -pipeliner-annotate-for-testing -o test.mir
And run the emission in isolation with:
llc < test.mir -run-pass=modulo-schedule-test
llvm-svn: 370705
Eli Friedman