GVN-Hoist appears to miscompile llvm-testsuite
SingleSource/Benchmarks/Misc/fbench.c at the moment.
I filed http://llvm.org/PR28880
This reverts commit r277786.
llvm-svn: 277909
Summary:
This is the 4c patch of the coroutine series. CoroElide pass now checks if PostSplit coro.begin
is referenced by coro.subfn.addr intrinsics. If so replace coro.subfn.addrs with an appropriate coroutine
subfunction associated with that coro.begin.
Documentation and overview is here: http://llvm.org/docs/Coroutines.html.
Upstreaming sequence (rough plan)
1.Add documentation. (https://reviews.llvm.org/D22603)
2.Add coroutine intrinsics. (https://reviews.llvm.org/D22659)
3.Add empty coroutine passes. (https://reviews.llvm.org/D22847)
4.Add coroutine devirtualization + tests.
ab) Lower coro.resume and coro.destroy (https://reviews.llvm.org/D22998)
c) Do devirtualization <= we are here
5.Add CGSCC restart trigger + tests.
6.Add coroutine heap elision + tests.
7.Add the rest of the logic (split into more patches)
Reviewers: majnemer
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D23229
llvm-svn: 277908
Fixes PR28764. Right now there is no way to test this, but (as
mentioned on the PR) with Michael Zolotukhin's yet to be checked in
LoopSimplify verfier, 8 of the llvm-lit tests for IRCE crash.
llvm-svn: 277891
Note that this fold really belongs in InstSimplify.
Refactoring here anyway as an intermediate step because
there's a planned addition to this function in D23134.
Differential Revision: https://reviews.llvm.org/D23223
llvm-svn: 277883
Summary:
Originally the plan was to use the custom worklist to do some block popping,
and because we don't actually need a visited set. The custom one we have
here is slightly broken, and it's not worth fixing vs using depth_first_iterator since we aren't going to go the route we originally
were.
Fixes PR28874
Reviewers: george.burgess.iv
Subscribers: llvm-commits, gberry
Differential Revision: https://reviews.llvm.org/D23187
llvm-svn: 277880
This fixes PR28825. The problem was that we only checked if a value from
a created inner loop is used in the outer loop, and fixed LCSSA for
them. But we missed to fixup LCSSA for values used in exits of the outer
loop.
llvm-svn: 277877
Summary:
Chrome on Linux uses WholeProgramDevirt for speed ups, and it's
important to detect regressions on both sides: the toolchain,
if fewer methods get devirtualized after an update, and Chrome,
if an innocently looking change caused many hot methods become
virtual again.
The need to track devirtualized methods is not Chrome-specific,
but it's probably the only user of the pass at this time.
Reviewers: kcc
Differential Revision: https://reviews.llvm.org/D23219
llvm-svn: 277856
Summary:
This is another refactoring to break up the one function into three logical components functions.
Another non-functional change before we start added in features.
Reviewers: nadav, mehdi_amini, majnemer
Subscribers: twoh, freik, llvm-commits
Differential Revision: https://reviews.llvm.org/D23102
llvm-svn: 277855
Summary: We do not care about intrinsic calls when assigning discriminators.
Reviewers: davidxl, dnovillo
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D23212
llvm-svn: 277843
This generated IR based on the order of evaluation, which is different
between GCC and Clang. With that in mind you get bootstrap miscompares
if you compare a Clang built with GCC-built Clang vs. Clang built with
Clang-built Clang. Diagnosing that made my head hurt.
This also reverts commit r277337, which "fixed" the test case.
llvm-svn: 277820
Summary:
Turn (select C, (sext A), B) into (sext (select C, A, B')) when A is i1 and
B is a compatible constant, also for zext instead of sext. This will then be
further folded into logical operations.
The transformation would be valid for non-i1 types as well, but other parts of
InstCombine prefer to have sext from non-i1 as an operand of select.
Motivated by the shader compiler frontend in Mesa for AMDGPU, which emits i32
for boolean operations. With this change, the boolean logic is fully
recovered.
Reviewers: majnemer, spatel, tstellarAMD
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D22747
llvm-svn: 277801
The patch splits a complex && if condition into easier to read and understand
logic. That wrong early exit condition was letting some instructions with not
all operands available pass through when HoistingGeps was true.
Differential Revision: https://reviews.llvm.org/D23174
llvm-svn: 277785
Add a generalized IRBuilderCallbackInserter, which is just given a
callback to execute after insertion. This can be used to get rid of
the custom inserter in InstCombine, which will in turn allow me to add
target specific InstCombineCalls API for intrinsics without horrible
layering violations.
llvm-svn: 277784
Shifts with a uniform but non-constant count were considered very expensive to
vectorize, because the splat of the uniform count and the shift would tend to
appear in different blocks. That made the splat invisible to ISel, and we'd
scalarize the shift at codegen time.
Since r201655, CodeGenPrepare sinks those splats to be next to their use, and we
are able to select the appropriate vector shifts. This updates the cost model to
to take this into account by making shifts by a uniform cheap again.
Differential Revision: https://reviews.llvm.org/D23049
llvm-svn: 277782
This is the forth patch in the coroutine series. CoroEaly pass now lowers coro.resume
and coro.destroy intrinsics by replacing them with an indirect call to an address
returned by coro.subfn.addr intrinsic. This is done so that CGPassManager recognizes
devirtualization when CoroElide replaces a call to coro.subfn.addr with an appropriate
function address.
Patch by Gor Nishanov!
Differential Revision: https://reviews.llvm.org/D22998
llvm-svn: 277765
I'm removing a misplaced pair of more specific folds from InstCombine in this patch as well,
so we know where those folds are happening in InstSimplify.
llvm-svn: 277738
Summary:
TargetBaseAlign is no longer required since LSV checks if target allows misaligned accesses.
A constant defining a base alignment is still needed for stack accesses where alignment can be adjusted.
Previous patch (D22936) was reverted because tests were failing. This patch also fixes the cause of those failures:
- x86 failing tests either did not have the right target, or the right alignment.
- NVPTX failing tests did not have the right alignment.
- AMDGPU failing test (merge-stores) should allow vectorization with the given alignment but the target info
considers <3xi32> a non-standard type and gives up early. This patch removes the condition and only checks
for a maximum size allowed and relies on the next condition checking for %4 for correctness.
This should be revisited to include 3xi32 as a MVT type (on arsenm's non-immediate todo list).
Note that checking the sizeInBits for a MVT is undefined (leads to an assertion failure),
so we need to create an EVT, hence the interface change in allowsMisaligned to include the Context.
Reviewers: arsenm, jlebar, tstellarAMD
Subscribers: jholewinski, arsenm, mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D23068
llvm-svn: 277735
Not a correctness issue, but it would be nice if we didn't have to
recompute our block numbering (worst-case) every time we move MSSA.
llvm-svn: 277652
Limit the number of times the while(1) loop is executed. With this restriction
the number of hoisted instructions does not change in a significant way on the
test-suite.
Differential Revision: https://reviews.llvm.org/D23028
llvm-svn: 277651
With this patch we compute the DFS numbers of instructions only once and update
them during the code generation when an instruction gets hoisted.
Differential Revision: https://reviews.llvm.org/D23021
llvm-svn: 277650
With this patch we compute the MemorySSA once and update it in the code generator.
Differential Revision: https://reviews.llvm.org/D22966
llvm-svn: 277649
This reverts commit r277611 and the followup r277614.
Bootstrap builds and chromium builds are crashing during inlining after
this change.
llvm-svn: 277642
This is a follow-up to r277637. It teaches MemorySSA that invariant
loads (and loads of provably constant memory) are always liveOnEntry.
llvm-svn: 277640
This patch makes MemorySSA recognize atomic/volatile loads, and makes
MSSA treat said loads specially. This allows us to be a bit more
aggressive in some cases.
Administrative note: Revision was LGTM'ed by reames in person.
Additionally, this doesn't include the `invariant.load` recognition in
the differential revision, because I feel it's better to commit that
separately. Will commit soon.
Differential Revision: https://reviews.llvm.org/D16875
llvm-svn: 277637
Summary:
InstCombine unfolds expressions of the form `zext(or(icmp, icmp))` to `or(zext(icmp), zext(icmp))` such that in a later iteration of InstCombine the exposed `zext(icmp)` instructions can be optimized. We now combine this unfolding and the subsequent `zext(icmp)` optimization to be performed together. Since the unfolding doesn't happen separately anymore, we also again enable the folding of `logic(cast(icmp), cast(icmp))` expressions to `cast(logic(icmp, icmp))` which had been disabled due to its interference with the unfolding transformation.
Tested via `make check` and `lnt`.
Background
==========
For a better understanding on how it came to this change we subsequently summarize its history. In commit r275989 we've already tried to enable the folding of `logic(cast(icmp), cast(icmp))` to `cast(logic(icmp, icmp))` which had to be reverted in r276106 because it could lead to an endless loop in InstCombine (also see http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20160718/374347.html). The root of this problem is that in `visitZExt()` in InstCombineCasts.cpp there also exists a reverse of the above folding transformation, that unfolds `zext(or(icmp, icmp))` to `or(zext(icmp), zext(icmp))` in order to expose `zext(icmp)` operations which would then possibly be eliminated by subsequent iterations of InstCombine. However, before these `zext(icmp)` would be eliminated the folding from r275989 could kick in and cause InstCombine to endlessly switch back and forth between the folding and the unfolding transformation. This is the reason why we now combine the `zext`-unfolding and the elimination of the exposed `zext(icmp)` to happen at one go because this enables us to still allow the cast-folding in `logic(cast(icmp), cast(icmp))` without entering an endless loop again.
Details on the submitted changes
================================
- In `visitZExt()` we combine the unfolding and optimization of `zext` instructions.
- In `transformZExtICmp()` we have to use `Builder->CreateIntCast()` instead of `CastInst::CreateIntegerCast()` to make sure that the new `CastInst` is inserted in a `BasicBlock`. The new calls to `transformZExtICmp()` that we introduce in `visitZExt()` would otherwise cause according assertions to be triggered (in our case this happend, for example, with lnt for the MultiSource/Applications/sqlite3 and SingleSource/Regression/C++/EH/recursive-throw tests). The subsequent usage of `replaceInstUsesWith()` is necessary to ensure that the new `CastInst` replaces the `ZExtInst` accordingly.
- In InstCombineAndOrXor.cpp we again allow the folding of casts on `icmp` instructions.
- The instruction order in the optimized IR for the zext-or-icmp.ll test case is different with the introduced changes.
- The test cases in zext.ll have been adopted from the reverted commits r275989 and r276105.
Reviewers: grosser, majnemer, spatel
Subscribers: eli.friedman, majnemer, llvm-commits
Differential Revision: https://reviews.llvm.org/D22864
Contributed-by: Matthias Reisinger <d412vv1n@gmail.com>
llvm-svn: 277635
