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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371121 91177308-0d34-0410-b5e6-96231b3b80d8
Now that we look through copies, it's possible to visit registers that
have a register class constraint but not a type constraint. Avoid looking
through copies when this occurs as the SrcReg won't be able to determine
it's bit width or any known bits.
Along the same lines, if the initial query is on a register that doesn't
have a type constraint then the result is a default-constructed KnownBits,
that is, a 1-bit fully-unknown value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371116 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371114 91177308-0d34-0410-b5e6-96231b3b80d8
The code was incorrectly counting the number of identical instructions,
and therefore tried to predicate an instruction which should not have
been predicated. This could have various effects: a compiler crash,
an assembler failure, a miscompile, or just generating an extra,
unnecessary instruction.
Instead of depending on TargetInstrInfo::removeBranch, which only
works on analyzable branches, just remove all branch instructions.
Fixes https://bugs.llvm.org/show_bug.cgi?id=43121 and
https://bugs.llvm.org/show_bug.cgi?id=41121 .
Differential Revision: https://reviews.llvm.org/D67203
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371111 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371051 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371045 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370996 91177308-0d34-0410-b5e6-96231b3b80d8
Moving MIRCanonicalizerPass vreg renaming code to MIRVRegNamerUtils so that it
can be reused in another pass (ie planing to write a standalone mir-namer pass).
I'm going to write a mir-namer pass so that next time someone has to author a
test in MIR, they can use it to cleanup the naming and make it more readable by
having the numbered vregs swapped out with named vregs.
Differential Revision: https://reviews.llvm.org/D67114
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370985 91177308-0d34-0410-b5e6-96231b3b80d8
Apologies, due to a git SNAFU this fix (dump doesn't exist and silence unused variables) stayed in my index rather than applying to rL370893.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370894 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370893 91177308-0d34-0410-b5e6-96231b3b80d8
When comparing variable locations, LiveDebugValues currently considers only
the machine location, ignoring any DIExpression applied to it. This is a
problem because that DIExpression can do pretty much anything to the machine
location, for example dereferencing it.
This patch adds DIExpressions to that comparison; now variables based on the
same register/memory-location but with different expressions will compare
differently, and be dropped if we attempt to merge them between blocks. This
reduces variable coverage-range a little, but only because we were producing
broken locations.
Differential Revision: https://reviews.llvm.org/D66942
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370877 91177308-0d34-0410-b5e6-96231b3b80d8
On release builds, 'MI' isn't used by anything (it's already inserted into a
block by BuildMI), while on non-release builds it's used by a LLVM_DEBUG
statement. Mark as explicitly used to avoid the warning.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370870 91177308-0d34-0410-b5e6-96231b3b80d8
Similar to the issue with G_ZEXT that was fixed earlier, this is a quick
to fall back if the source type is not exactly half of the dest type.
Fixes the clang-cmake-aarch64-lld bot build.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370847 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370822 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Simplify the right shift of the intermediate result (given
in four parts) by using funnel shift.
There are some impact on lit tests, but that seems to be
related to register allocation differences due to how FSHR
is expanded on X86 (giving a slightly different operand order
for the OR operations compared to the old code).
Reviewers: leonardchan, RKSimon, spatel, lebedev.ri
Reviewed By: RKSimon
Subscribers: hiraditya, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, s.egerton, pzheng, bevinh, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67036
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370813 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370705 91177308-0d34-0410-b5e6-96231b3b80d8
The motivating bugs are:
https://bugs.llvm.org/show_bug.cgi?id=41340https://bugs.llvm.org/show_bug.cgi?id=42697
As discussed there, we could view this as a failure of IR canonicalization,
but then we would need to implement a backend fixup with target overrides
to get this right in all cases. Instead, we can just view this as a codegen
opportunity. It's not even clear for x86 exactly when we should favor
test+set; some CPUs have better theoretical throughput for the ALU ops than
bt/test.
This patch is made more complicated than I expected because there's an early
DAGCombine for 'and' that can change types of the intermediate ops via
trunc+anyext.
Differential Revision: https://reviews.llvm.org/D66687
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370668 91177308-0d34-0410-b5e6-96231b3b80d8
The missing line added by this patch ensures that only spilt variable
locations are candidates for being restored from the stack. Otherwise,
register or constant-value information can be interpreted as a spill
location, through a union.
The added regression test replicates a scenario where this occurs: the
stack load from [rsp] causes the register-location DBG_VALUE to be
"restored" to rsi, when it should be left alone. See PR43058 for details.
Un x-fail a test that was suffering from this from a previous patch.
Differential Revision: https://reviews.llvm.org/D66895
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370648 91177308-0d34-0410-b5e6-96231b3b80d8
The motivating case for this is a long way from here:
https://bugs.llvm.org/show_bug.cgi?id=43146
...but I think this is where we have to start.
We need to canonicalize/optimize sequences of shift and logic to ease
pattern matching for things like bswap and improve perf in general.
But without the artificial limit of '!LegalTypes' (early combining),
there are a lot of test diffs, and not all are good.
In the minimal tests added for this proposal, x86 should have better
throughput in all cases. AArch64 is neutral for scalar tests because
it can fold shifts into bitwise logic ops.
There are 3 shift opcodes and 3 logic opcodes for a total of 9 possible patterns:
https://rise4fun.com/Alive/VlIhttps://rise4fun.com/Alive/n1mhttps://rise4fun.com/Alive/1Vn
Differential Revision: https://reviews.llvm.org/D67021
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370617 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This fixes the bugzilla id 43183 which triggerd by the following commit:
[RISCV] Avoid generating AssertZext for LP64 ABI when lowering floating LibCall
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370604 91177308-0d34-0410-b5e6-96231b3b80d8
This is not quite NFC because the SDLoc propagation is changed,
but there are no regression test diffs from that.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370587 91177308-0d34-0410-b5e6-96231b3b80d8
Narrowing stores when the target doesn't support the narrow version
forces the target to expand into a load-modify-store sequence, which
is highly suboptimal. The information narrowing throws away (legality
of the inverse transform) is hard to re-analyze. If the target doesn't
support a store of the narrow type, don't narrow even in pre-legalize
mode.
No test as this is DAGCombiner and depends on target bits.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370576 91177308-0d34-0410-b5e6-96231b3b80d8
Restructured the code a little bit in preparation for adding
UMULFIXSAT. I think it will be easier to understand the code
if not interleaving the codegen for signed/unsigned/saturated
cases that much.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370569 91177308-0d34-0410-b5e6-96231b3b80d8
This is the first stage in refactoring the pipeliner and making it more
accessible for backends to override and control. This separates the logic and
state required to *emit* a scheudule from the logic that *computes* and
validates a schedule.
This will enable (a) new schedule emitters and (b) new modulo scheduling
implementations to coexist.
NFC.
Differential Revision: https://reviews.llvm.org/D67006
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370500 91177308-0d34-0410-b5e6-96231b3b80d8
Just disable NSW/NUW flags. This matches what we're already doing for the other situations for these nodes, it was just missed for the demanded constant case.
Noticed by inspection - confirmed in offline discussion with @spatel. I've checked we have test coverage in the x86 extract-bits.ll and extract-lowbits.ll tests
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370497 91177308-0d34-0410-b5e6-96231b3b80d8
This is hidden behind a (scalar-only) isOneConstant(N1) check at the moment, but once we get around to adding vector support we need to ensure we're dealing with the scalar bitwidth, not the total.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370468 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Found a couple of places in the code where all the PHI nodes
of a MBB is updated, replacing references to one MBB by
reference to another MBB instead.
This patch simply refactors the code to use a common helper
(MachineBasicBlock::replacePhiUsesWith) for such PHI node
updates.
Reviewers: t.p.northover, arsenm, uabelho
Subscribers: wdng, hiraditya, jsji, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66750
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370463 91177308-0d34-0410-b5e6-96231b3b80d8
Return a proper zero vector, just in case some elements are undef.
Noticed by inspection after dealing with a similar issue in PR43159.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370460 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Change LiveDebugValues so that it inserts entry values after the bundle
which contains the clobbering instruction. Previously it would insert
the debug value after the bundle head using insertAfter(), breaking the
bundle.
Reviewers: djtodoro, NikolaPrica, aprantl, vsk
Reviewed By: vsk
Subscribers: hiraditya, llvm-commits
Tags: #debug-info, #llvm
Differential Revision: https://reviews.llvm.org/D66888
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370448 91177308-0d34-0410-b5e6-96231b3b80d8
When the number of return values exceeds the number of registers available,
SelectionDAGBuilder::visitRet transforms a function's return to use a
pointer to a buffer to hold return values. When the returned value is an
operator such as extractvalue, the value may have a non-zero result number.
Add that number to the indexing when obtaining the values to store.
This fixes https://bugs.llvm.org/show_bug.cgi?id=43132.
Differential Revision: https://reviews.llvm.org/D66978
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370430 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts r369664 (git commit 51f48295cbe8fa3a44db263b528dd9f7bae7bf9a)
It causes many benchmark regressions, internally and in llvm's benchmark suite.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370398 91177308-0d34-0410-b5e6-96231b3b80d8
I dropped the DemandedElts since it seems to be missing from some of
the new interfaces, but not others.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370389 91177308-0d34-0410-b5e6-96231b3b80d8
Puyan Lotfi