This reverts commit 52621307bcab2013e8833f3317cebd63a6db3885.
Tests have been failing all night with
[0/2] ACTION //llvm/test:check-llvm(//llvm/utils/gn/build/toolchain:unix)
-- Testing: 33647 tests, 64 threads --
Testing: 0 .. 10..
UNRESOLVED: LLVM :: CodeGen/AMDGPU/GlobalISel/isel-blendi-gettargetconstant.ll (6943 of 33647)
******************** TEST 'LLVM :: CodeGen/AMDGPU/GlobalISel/isel-blendi-gettargetconstant.ll' FAILED ********************
Test has no run line!
********************
Since there were other concerns on https://reviews.llvm.org/D67785,
I'm just reverting for now.
llvm-svn: 372383
The way MachinePipeliner uses these target hooks is stateful - we reduce trip
count by one per call to reduceLoopCount. It's a little overfit for hardware
loops, where we don't have to worry about stitching a loop induction variable
across prologs and epilogs (the induction variable is implicit).
This patch introduces a new API:
/// Analyze loop L, which must be a single-basic-block loop, and if the
/// conditions can be understood enough produce a PipelinerLoopInfo object.
virtual std::unique_ptr<PipelinerLoopInfo>
analyzeLoopForPipelining(MachineBasicBlock *LoopBB) const;
The return value is expected to be an implementation of the abstract class:
/// Object returned by analyzeLoopForPipelining. Allows software pipelining
/// implementations to query attributes of the loop being pipelined.
class PipelinerLoopInfo {
public:
virtual ~PipelinerLoopInfo();
/// Return true if the given instruction should not be pipelined and should
/// be ignored. An example could be a loop comparison, or induction variable
/// update with no users being pipelined.
virtual bool shouldIgnoreForPipelining(const MachineInstr *MI) const = 0;
/// Create a condition to determine if the trip count of the loop is greater
/// than TC.
///
/// If the trip count is statically known to be greater than TC, return
/// true. If the trip count is statically known to be not greater than TC,
/// return false. Otherwise return nullopt and fill out Cond with the test
/// condition.
virtual Optional<bool>
createTripCountGreaterCondition(int TC, MachineBasicBlock &MBB,
SmallVectorImpl<MachineOperand> &Cond) = 0;
/// Modify the loop such that the trip count is
/// OriginalTC + TripCountAdjust.
virtual void adjustTripCount(int TripCountAdjust) = 0;
/// Called when the loop's preheader has been modified to NewPreheader.
virtual void setPreheader(MachineBasicBlock *NewPreheader) = 0;
/// Called when the loop is being removed.
virtual void disposed() = 0;
};
The Pipeliner (ModuloSchedule.cpp) can use this object to modify the loop while
allowing the target to hold its own state across all calls. This API, in
particular the disjunction of creating a trip count check condition and
adjusting the loop, improves the code quality in ModuloSchedule.cpp.
llvm-svn: 372376
Summary: This fixes a crasher introduced by r372338.
Reviewers: echristo, arsenm
Subscribers: jvesely, wdng, nhaehnle, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67785
Tighten up the test case.
llvm-svn: 372366
If an instruction had multiple subregister defs, and one of them was
undef, this would improperly conclude all other lanes are
killed. There could still be other defs of those read-undef lanes in
other operands. This would improperly remove register uses from
CurrentVRegUses, so the visitation of later operands would not find
the necessary register dependency. This would also mean this would
fail or not depending on how different subregister def operands were
ordered.
On an undef subregister def, scan the instruction for other
subregister defs and avoid killing those.
This possibly should be deferring removing anything from
CurrentVRegUses until the entire instruction has been processed
instead.
llvm-svn: 372362
This reverts r372314, reapplying r372285 and the commits which depend
on it (r372286-r372293, and r372296-r372297)
This was missing one switch to getTargetConstant in an untested case.
llvm-svn: 372338
This patch converts the DAGCombine isNegatibleForFree/GetNegatedExpression into overridable TLI hooks and includes a demonstration X86 implementation.
The intention is to let us extend existing FNEG combines to work more generally with negatible float ops, allowing it work with target specific combines and opcodes (e.g. X86's FMA variants).
Unlike the SimplifyDemandedBits, we can't just handle target nodes through a Target callback, we need to do this as an override to allow targets to handle generic opcodes as well. This does mean that the target implementations has to duplicate some checks (recursion depth etc.).
I've only begun to replace X86's FNEG handling here, handling FMADDSUB/FMSUBADD negation and some low impact codegen changes (some FMA negatation propagation). We can build on this in future patches.
Differential Revision: https://reviews.llvm.org/D67557
llvm-svn: 372333
This broke the Chromium build, causing it to fail with e.g.
fatal error: error in backend: Cannot select: t362: v4i32 = X86ISD::VSHLI t392, Constant:i8<15>
See llvm-commits thread of r372285 for details.
This also reverts r372286, r372287, r372288, r372289, r372290, r372291,
r372292, r372293, r372296, and r372297, which seemed to depend on the
main commit.
> Encode them directly as an imm argument to G_INTRINSIC*.
>
> Since now intrinsics can now define what parameters are required to be
> immediates, avoid using registers for them. Intrinsics could
> potentially want a constant that isn't a legal register type. Also,
> since G_CONSTANT is subject to CSE and legalization, transforms could
> potentially obscure the value (and create extra work for the
> selector). The register bank of a G_CONSTANT is also meaningful, so
> this could throw off future folding and legalization logic for AMDGPU.
>
> This will be much more convenient to work with than needing to call
> getConstantVRegVal and checking if it may have failed for every
> constant intrinsic parameter. AMDGPU has quite a lot of intrinsics wth
> immarg operands, many of which need inspection during lowering. Having
> to find the value in a register is going to add a lot of boilerplate
> and waste compile time.
>
> SelectionDAG has always provided TargetConstant for constants which
> should not be legalized or materialized in a register. The distinction
> between Constant and TargetConstant was somewhat fuzzy, and there was
> no automatic way to force usage of TargetConstant for certain
> intrinsic parameters. They were both ultimately ConstantSDNode, and it
> was inconsistently used. It was quite easy to mis-select an
> instruction requiring an immediate. For SelectionDAG, start emitting
> TargetConstant for these arguments, and using timm to match them.
>
> Most of the work here is to cleanup target handling of constants. Some
> targets process intrinsics through intermediate custom nodes, which
> need to preserve TargetConstant usage to match the intrinsic
> expectation. Pattern inputs now need to distinguish whether a constant
> is merely compatible with an operand or whether it is mandatory.
>
> The GlobalISelEmitter needs to treat timm as a special case of a leaf
> node, simlar to MachineBasicBlock operands. This should also enable
> handling of patterns for some G_* instructions with immediates, like
> G_FENCE or G_EXTRACT.
>
> This does include a workaround for a crash in GlobalISelEmitter when
> ARM tries to uses "imm" in an output with a "timm" pattern source.
llvm-svn: 372314
We needn't BFI each lane individually into a predicate register when each lane
in the same. A simple sign extend and a vmsr will do.
Differential Revision: https://reviews.llvm.org/D67653
llvm-svn: 372313
This needs special handling due to some subtargets that have a
nonstandard register layout for f16 vectors
Also reject some illegal types on other targets.
llvm-svn: 372293
Encode them directly as an imm argument to G_INTRINSIC*.
Since now intrinsics can now define what parameters are required to be
immediates, avoid using registers for them. Intrinsics could
potentially want a constant that isn't a legal register type. Also,
since G_CONSTANT is subject to CSE and legalization, transforms could
potentially obscure the value (and create extra work for the
selector). The register bank of a G_CONSTANT is also meaningful, so
this could throw off future folding and legalization logic for AMDGPU.
This will be much more convenient to work with than needing to call
getConstantVRegVal and checking if it may have failed for every
constant intrinsic parameter. AMDGPU has quite a lot of intrinsics wth
immarg operands, many of which need inspection during lowering. Having
to find the value in a register is going to add a lot of boilerplate
and waste compile time.
SelectionDAG has always provided TargetConstant for constants which
should not be legalized or materialized in a register. The distinction
between Constant and TargetConstant was somewhat fuzzy, and there was
no automatic way to force usage of TargetConstant for certain
intrinsic parameters. They were both ultimately ConstantSDNode, and it
was inconsistently used. It was quite easy to mis-select an
instruction requiring an immediate. For SelectionDAG, start emitting
TargetConstant for these arguments, and using timm to match them.
Most of the work here is to cleanup target handling of constants. Some
targets process intrinsics through intermediate custom nodes, which
need to preserve TargetConstant usage to match the intrinsic
expectation. Pattern inputs now need to distinguish whether a constant
is merely compatible with an operand or whether it is mandatory.
The GlobalISelEmitter needs to treat timm as a special case of a leaf
node, simlar to MachineBasicBlock operands. This should also enable
handling of patterns for some G_* instructions with immediates, like
G_FENCE or G_EXTRACT.
This does include a workaround for a crash in GlobalISelEmitter when
ARM tries to uses "imm" in an output with a "timm" pattern source.
llvm-svn: 372285
Summary:
Large slowdowns were observed in Rust due to many small, constant
sized copies in conjunction with poorly-optimized memory.copy
implementations. Since memory.copy cannot be expected to be inlined
efficiently by engines at this time, stop using it for the smallest
copies. We continue to lower all memcpy intrinsics to memory.copy,
though.
Reviewers: aheejin, alexcrichton
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, JDevlieghere, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67639
llvm-svn: 372275
Since we now lower most tail calls, it makes sense to support musttail.
Instead of always falling back to SelectionDAG, only fall back when a musttail
call was not able to be emitted as a tail call. Once we can handle most
incoming and outgoing arguments, we can change this to a `report_fatal_error`
like in ISelLowering.
Remove the assert that we don't have varargs and a musttail, and replace it
with a return false. Implementing this requires that we implement
`saveVarArgRegisters` from AArch64ISelLowering, which is an entirely different
patch.
Add GlobalISel lines to vararg-tallcall.ll to make sure that we produce correct
code. Right now we only fall back, but eventually this will be relevant.
Differential Revision: https://reviews.llvm.org/D67681
llvm-svn: 372273
DIFlagBlockByRefStruct is an unused DIFlag that originally was used by
clang to express (Objective-)C block captures in debug info. For the
last year Clang has been emitting complex DIExpressions to describe
block captures instead, which makes all the code supporting this flag
redundant.
This patch removes the flag and all supporting "dead" code, so we can
reuse the bit for something else in the future.
Since this only affects debug info generated by Clang with the block
extension this mostly affects Apple platforms and I don't have any
bitcode compatibility concerns for removing this. The Verifier will
reject debug info that uses the bit and thus degrade gracefully when
LTO'ing older bitcode with a newer compiler.
rdar://problem/44304813
Differential Revision: https://reviews.llvm.org/D67453
llvm-svn: 372272
Summary:
`DAGCombiner::visitADDLikeCommutative()` already has a sibling fold:
`(add X, Carry) -> (addcarry X, 0, Carry)`
This fold, as suggested by @efriedma, helps recover from //some//
of the regressions of D62266
Reviewers: efriedma, deadalnix
Subscribers: javed.absar, kristof.beyls, llvm-commits, efriedma
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62392
llvm-svn: 372259
Summary:
AArch64 GlobalISel doesn't support MachO's large code model, so this patch
adds a check for that combination before implicitly enabling it.
Reviewers: paquette
Subscribers: kristof.beyls, ributzka, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67724
llvm-svn: 372256
Summary:
As discussed in https://reviews.llvm.org/D62341#1515637,
for MIPS `add %x, -1` isn't optimal. Unlike X86 there
are no fastpaths to matearialize such `-1`/`1` vector constants,
and `sub %x, 1` results in better codegen,
so undo canonicalization
Reviewers: atanasyan, Petar.Avramovic, RKSimon
Reviewed By: atanasyan
Subscribers: sdardis, arichardson, hiraditya, jrtc27, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66805
llvm-svn: 372254
We need "xgot" flag in the MipsAsmParser to implement correct expansion
of some pseudo instructions in case of using 32-bit GOT (XGOT).
MipsAsmParser does not have reference to MipsSubtarget but has a
reference to "feature bit set".
llvm-svn: 372220
This patch fixes a bug exposed by D65653 where a subsequent invocation
of `determineCalleeSaves` ends up with a different size for the callee
save area, leading to different frame-offsets in debug information.
In the invocation by PEI, `determineCalleeSaves` tries to determine
whether it needs to spill an extra callee-saved register to get an
emergency spill slot. To do this, it calls 'estimateStackSize' and
manually adds the size of the callee-saves to this. PEI then allocates
the spill objects for the callee saves and the remaining frame layout
is calculated accordingly.
A second invocation in LiveDebugValues causes estimateStackSize to return
the size of the stack frame including the callee-saves. Given that the
size of the callee-saves is added to this, these callee-saves are counted
twice, which leads `determineCalleeSaves` to believe the stack has
become big enough to require spilling an extra callee-save as emergency
spillslot. It then updates CalleeSavedStackSize with a larger value.
Since CalleeSavedStackSize is used in the calculation of the frame
offset in getFrameIndexReference, this leads to incorrect offsets for
variables/locals when this information is recalculated after PEI.
Reviewers: omjavaid, eli.friedman, thegameg, efriedma
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D66935
llvm-svn: 372204
This generates worse code, but matches what is done for avx2 and
prevents crashes when more arguments are passed than we have
registers for.
llvm-svn: 372200
Currently, not all user specified relocations
(with clang intrinsic __builtin_preserve_access_index())
will turn into relocations.
In the current implementation, a __builtin_preserve_access_index()
chain is turned into relocation only if the result of the clang
intrinsic is used in a function call or a nonzero offset computation
of getelementptr. For all other cases, the relocatiion request
is ignored and the __builtin_preserve_access_index() is turned
into regular getelementptr instructions.
The main reason is to mimic bpf_probe_read() requirement.
But there are other use cases where relocatable offset is
generated but not used for bpf_probe_read(). This patch
relaxed previous constraints when to generate relocations.
Now, all user __builtin_preserve_access_index() will have
relocations generated.
Differential Revision: https://reviews.llvm.org/D67688
llvm-svn: 372198
r361845 changed the way we handle "D16" vs. "D32" targets; there used to
be a negative "d16" which removed instructions from the instruction set,
and now there's a "d32" feature which adds instructions to the
instruction set. This is good, but there was an oversight in the
implementation: the behavior of VFPv2 was changed. In particular, the
"vfp2" feature was changed to imply "d32". This is wrong: VFPv2 only
supports 16 D registers.
In practice, this means if you specify -mfpu=vfpv2, the compiler will
generate illegal instructions.
This patch gets rid of "vfp2d16" and "vfp2d16sp", and fixes "vfp2" and
"vfp2sp" so they don't imply "d32".
Differential Revision: https://reviews.llvm.org/D67375
llvm-svn: 372186
This adds support for `-tailcallopt` tail calls to CallLowering. This
piggy-backs off the changes from D67577, since doing it without a bit of
refactoring gets extremely ugly.
Support is basically ported from AArch64ISelLowering. The main difference here
is that tail calls in `-tailcallopt` change the ABI, so there's some extra
bookkeeping for the stack.
Show that we are correctly lowering these by updating tail-call.ll.
Also show that we don't do anything strange in general by updating
fastcc-reserved.ll, which passes `-tailcallopt`, but doesn't emit any tail
calls.
Differential Revision: https://reviews.llvm.org/D67580
llvm-svn: 372177
We currently produce a load, followed by (possibly a move for integers and) a
splat as separate instructions. VSX has always had a splatting load for
doublewords, but as of Power9, we have it for words as well. This patch just
exploits these instructions.
Differential revision: https://reviews.llvm.org/D63624
llvm-svn: 372139
We were previously using the SelectT2AddrModeImm7 for both normal and narrowing
MVE loads/stores. As the narrowing instructions do not accept sp as a register,
it makes little sense to optimise a FrameIndex into the load, only to have to
recover that later on. This adds a SelectTAddrModeImm7 which does not do that
folding, and uses it for narrowing load/store patterns.
Differential Revision: https://reviews.llvm.org/D67489
llvm-svn: 372134
Similar to D67327, but this time for the FP16 VLDR and VSTR instructions that
use the AddrMode5FP16 addressing mode. We need to reserve an emergency spill
slot for instructions that will be out of range to use sp directly.
AddrMode5FP16 is 8 bits with a scale of 2.
Differential Revision: https://reviews.llvm.org/D67483
llvm-svn: 372132
Remove setPreservesCFG from ARMConstantIslandPass and add a couple
of -verify-machine-dom-info instances into the existing codegen
tests.
llvm-svn: 372126
MVE loads and stores have a 7 bit immediate range, scaled by the length of the type. This needs to be taught to the stack estimation code to ensure that an emergency spill slot is reserved in case we run out of registers when materialising stack indices.
Also the narrowing loads/stores can be created with frame indices even though they do not accept SP as a register. We need in those cases to make sure we have an emergency register to use as the frame base, as SP can never be used.
Differential Revision: https://reviews.llvm.org/D67327
llvm-svn: 372114
