This optimisation isn't generally profitable for ARM, because we can
save/restore many registers in the prologue and epilogue using the PUSH
and POP instructions, but mostly use individual LDR/STR instructions for
other spills.
Differential revision: https://reviews.llvm.org/D64910
llvm-svn: 367670
- Avoid a crash when IPRA calls ARMFrameLowering::determineCalleeSaves
with a null RegScavenger. Simply not updating the register scavenger
is fine because IPRA only cares about the SavedRegs vector, the acutal
code of the function has already been generated at this point.
- Add a new hook to TargetRegisterInfo to get the set of registers which
can be clobbered inside a call, even if the compiler can see both
sides, by linker-generated code.
Differential revision: https://reviews.llvm.org/D64908
llvm-svn: 367669
Summary:
The old code can be simplified to define the element type of TailCalls as `BasicBlock` not `CallInst`. Also I use the for-range loop instead the for loop.
Reviewed By: jsji
Differential Revision: https://reviews.llvm.org/D64905
llvm-svn: 367644
AMDGPU sometimes has legal s16 and <2 x s16> operations, but all
registers are really 32-bit. An unmerge destination really should ben
widened to a 32-bit register. If widening a scalarizing vector with a
target size that matches the vector size, bitcast to integer and
extract the relevant bits with shifts.
I'm not sure if this is the right place for this. This could arguably
be part of widenScalar for the result. I also have a growing feeling
that we're missing a bitcast legalize action.
llvm-svn: 367604
If a type is larger than a legal type and needs to be split, we would previously allow the multiply to be decomposed even if the split multiply is legal. Since the shift + add/sub code would also need to be split, its not any better to decompose it.
This patch figures out what type the mul will eventually be legalized to and then uses that type for the query. I tried just returning false illegal types and letting them get handled after type legalization, but then we can't recognize and i64 constant splat on 32-bit targets since will be destroyed by type legalization. We could special case vectors of i64 to avoid that...
Differential Revision: https://reviews.llvm.org/D65533
llvm-svn: 367601
The note in the documentation suggests this restriction is a compile
time optimization for architectures that make heavy use of
bundling. Allowing virtual registers in a bundle is useful for some
(non-R600) AMDGPU use cases and are infrequent enough to matter.
A more common AMDGPU use case has already been using virtual registers
in bundles since r333691, although never calling finalizeBundle on
them and manually creating the use/def list on the BUNDLE
instruction. This is also relatively infrequent, and only happens for
consecutive sequences of some load/store types.
llvm-svn: 367597
This allows functions and globals to to be reordered later in the linking phase
(using the -symbol-ordering-file) even though reordering will be limited to
the scope of the explicit section.
Patch by Rahman Lavaee!
Differential Revision: https://reviews.llvm.org/D65478
llvm-svn: 367501
and partial fix.
Causes windows buildbot errors.
This reverts commit 6e65c34523963094acd0d6c94a5f5c64b32fe6aa and
53da7ca94343166ac68aef81db0398932fc258bb.
llvm-svn: 367496
X86 at least is able to use movmsk or kmov to move the mask to the scalar
domain. Then we can just use test instructions to test individual bits.
This is more efficient than extracting each mask element
individually.
I special cased v1i1 to use the previous behavior. This avoids
poor type legalization of bitcast of v1i1 to i1.
I've skipped expandload/compressstore as I think we need to
handle constant masks for those better first.
Many tests end up with duplicate test instructions due to tail
duplication in the branch folding pass. But the same thing
happens when constructing similar code in C. So its not unique
to the scalarization.
Not sure if this lowering code will also be good for other targets,
but we're only testing X86 today.
Differential Revision: https://reviews.llvm.org/D65319
llvm-svn: 367489
Summary: Honoring no signed zeroes is also available as a user control through clang separately regardless of fastmath or UnsafeFPMath context, DAG guards should reflect this context.
Reviewers: spatel, arsenm, hfinkel, wristow, craig.topper
Reviewed By: spatel
Subscribers: rampitec, foad, nhaehnle, wuzish, nemanjai, jvesely, wdng, javed.absar, MaskRay, jsji
Differential Revision: https://reviews.llvm.org/D65170
llvm-svn: 367486
Summary:
This will make it possible to improve IPRA by taking into account
register usage in indirect calls.
NFC yet; this is just laying the groundwork to start building
up patches to take advantage of the information for improved register
allocation.
Reviewers: aditya_nandakumar, volkan, qcolombet, arsenm, rovka, aemerson, paquette
Subscribers: sdardis, wdng, javed.absar, hiraditya, jrtc27, atanasyan, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65488
llvm-svn: 367476
This makes the field wider than MachineOperand::SubReg_TargetFlags so that
we don't end up silently truncating any higher bits. We should still catch
any bits truncated from the MachineOperand field as a consequence of the
assertion in MachineOperand::setTargetFlags().
Differential Revision: https://reviews.llvm.org/D65465
llvm-svn: 367474
to bail out in store merging dependence check.
We run into a case where dependence check in store merging bail out many times
for the same store and root nodes in a huge basicblock. That increases compile
time by almost 100x. The patch add a map to track how many times the bailing
out happen for the same store and root, and if it is over a limit, stop
considering the store with the same root as a merging candidate.
Differential Revision: https://reviews.llvm.org/D65174
llvm-svn: 367472
Add an option to control whether or not to enable store merging in dag combiner
so we can workaround some bugs more easily.
Differential Revision: https://reviews.llvm.org/D65482
llvm-svn: 367365
Addresses number of comment made on D64652 after commiting:
- Reorders function decls in the TargetLoweringObjectFileXCOFF class.
- Fix comment in MCSectionXCOFF to include description of external reference
csects.
- Convert several llvm_unreachables to report_fatal_error
- Convert several dyn_casts to casts as they are expected not to fail.
- Avoid copying DataLayout object.
llvm-svn: 367324
This allows us to peek through BITCASTs, attempt to simplify the source operand, and then bitcast back.
This reapplies rL367091 which was reverted at rL367118 - we were inconsistently peeking through the bitcasts to the source value.
Fixes PR42777
llvm-svn: 367174
If anything called the recursive isKnownNeverNaN/computeKnownBits/ComputeNumSignBits/SimplifyDemandedBits/SimplifyMultipleUseDemandedBits with an incorrect depth then we could continue to recurse if we'd already exceeded the depth limit.
This replaces the limit check (Depth == 6) with a (Depth >= 6) to make sure that we don't circumvent it.
This causes a couple of regressions as a mixture of calls (SimplifyMultipleUseDemandedBits + combineX86ShufflesRecursively) were calling with depths that were already over the limit. I've fixed SimplifyMultipleUseDemandedBits to not do this. combineX86ShufflesRecursively is trickier as we get a lot of regressions if we reduce its own limit from 8 to 6 (it also starts at Depth == 1 instead of Depth == 0 like the others....) - I'll see what I can do in future patches.
llvm-svn: 367171
We're getting reports of massive compile time increases because SimplifyMultipleUseDemandedBits was losing track of the depth and not earlying-out. No repro yet, but consider this a pre-emptive commit.
llvm-svn: 367169
Adds machine operand lowering for MCSymbolSDNodes to the PowerPC
backend. This is needed to produce call instructions in assembly for AIX
because the callee operand is a MCSymbolSDNode. The test is XFAIL'ed for
asserts due to a (valid) assertion in PEI that the AIX ABI isn't supported yet.
Differential Revision: https://reviews.llvm.org/D63738
llvm-svn: 367133
Eventually all of these will be moved over, but we create nodes in GetDemandedBits recursion at the moment which causes regressions when we try to remove them all.
llvm-svn: 367092
Summary:
In `block-placement` pass, it will create some patterns for unconditional we can do the simple early retrun.
But the `early-ret` pass is before `block-placement`, we don't want to run it again.
This patch is to do the simple early return to optimize the blocks at the last of `block-placement`.
Below is an example
```
BB: | BB:
XOR 3, 3, 4 | XOR 3, 3, 4
B TBB | B ChainBB
... | ...
ChainBB: | ChainBB:
B TBB | ADD 3, 3, 4
... | BLR
TBB: |
ADD 3, 3, 4 |
BLR |
```
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D63972
llvm-svn: 367080
This allows every serializer format to implement metaSerializer() and
return the corresponding meta serializer.
Original llvm-svn: 366946
Reverted llvm-svn: 367004
This fixes the unit tests on Windows bots.
llvm-svn: 367078
Currently, stack protector loads and stores are resolved during
LocalStackSlotAllocation (if the pass needs to run). When this is the
case, the base register assigned to the frame access is going to be one
of the vregs created during LocalStackSlotAllocation. This means that we
are keeping a pointer to the stack protector slot, and we're using this
pointer to load and store to it.
In case register pressure goes up, we may end up spilling this pointer
to the stack, which can be a security concern.
Instead, leave it to PEI to resolve the frame accesses. In order to do
that, we make all stack protector accesses go through frame index
operands, then PEI will resolve this using an offset from sp/fp/bp.
Differential Revision: https://reviews.llvm.org/D64759
llvm-svn: 367068
Summary:
This was originally reported in D62818.
https://rise4fun.com/Alive/oPH
InstCombine does the opposite fold, in hope that `C l>>/<< Y` expression
will be hoisted out of a loop if `Y` is invariant and `X` is not.
But as it is seen from the diffs here, if it didn't get hoisted,
the produced assembly is almost universally worse.
Much like with my recent "hoist add/sub by/from const" patches,
we should get almost universal win if we hoist constant,
there is almost always an "and/test by imm" instruction,
but "shift of imm" not so much, so we may avoid having to
materialize the immediate, and thus need one less register.
And since we now shift not by constant, but by something else,
the live-range of that something else may reduce.
Special care needs to be applied not to disturb x86 `BT` / hexagon `tstbit`
instruction pattern. And to not get into endless combine loop.
Reviewers: RKSimon, efriedma, t.p.northover, craig.topper, spatel, arsenm
Reviewed By: spatel
Subscribers: hiraditya, MaskRay, wuzish, xbolva00, nikic, nemanjai, jvesely, wdng, nhaehnle, javed.absar, tpr, kristof.beyls, jsji, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62871
llvm-svn: 366955
This introduces a new family of combiner helper routines that re-use the
target specific cost model from SelectionDAG, and generate inline implementations
of the memcpy family of intrinsics.
The combines are only enabled at optimization levels higher than -O0, and give
very substantial performance improvements.
Differential Revision: https://reviews.llvm.org/D65167
llvm-svn: 366951
r366317 added a legalization for s128 G_ICMP narrow scalar which tried to hard
code the result type of the new legalized G_SELECT. Change this to instead use
type of the original G_ICMP result and allow the target to legalize it if necessary
later.
llvm-svn: 366943
