CodeGenPrepare pass can sink pointer comparison across statepoint
to the point of use (see comment in IR/SafepointIRVerifier.cpp)
Due to specifics of statepoints, it is still legal to have tied
def and use rewritten to the same register in TwoAddress pass.
However, properly updating LiveIntervals and LiveVariables becomes
complicated. For simplicity, let's fall back to generic handling of
tied registers when we detect such case.
TODO: This fixes functional (assertion) failure. Ideally we should
try to recompute new live range/liveness in place.
Reviewed By: skatkov
Differential Revision: https://reviews.llvm.org/D132255
This interface allows a target to reject a proposed
SMS schedule. For Hexagon/PowerPC, all schedules
are accepted, leaving behavior unchanged. For ARM,
schedules which exceed register pressure limits are
rejected.
Also, two RegisterPressureTracker methods now need to be public so
that register pressure can be computed by more callers.
Reapplication of D128941/(reversion:D132037) with small fix.
Differential Revision: https://reviews.llvm.org/D132170
`RegisterClassInfo` caches information like allocation orders and reuses
it for multiple machine functions where possible. However the `MCPhysReg
*CalleeSavedRegs` field used to test whether the set of callee saved
registers changed did not work: After D28566
`MachineRegisterInfo::getCalleeSavedRegs()` can return dynamically
computed CSR sets that are only valid while the `MachineRegisterInfo`
object of the current function exists.
This changes the code to make a copy of the CSR list instead of keeping
a possibly invalid pointer around.
Differential Revision: https://reviews.llvm.org/D132080
Changed check line to accomodate assertion text difference on
mac and windows; added 'REQUIRES: asserts' line.
This reverts commit 89aaae57eacf77a6902ef8d4af5c92a3d6c642c2.
Similar to D132211, we can optimize x <s -1 ? x : -1 -> x <s 0 ? x : -1
Also improve the unsigned case from D132211 to use x != 0 which
will give a bnez instruction which might be compressible.
Differential Revision: https://reviews.llvm.org/D132252
if x == 1,
x > 1 ? x : 1 return x, which is also 1.
x > 0 ? x : 1 return 1.
Reduce the number of load 1 instructions.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D132211
This patch only add %pc_hi20/%pc_lo12/%plt relocations in order
to be able to generate gnu ld linkable relocation file for the
`hello world` IR :
```
@.str = private unnamed_addr constant [14 x i8] c"Hello world!\0A\00", align 1
define dso_local signext i32 @main() nounwind {
entry:
%call = call signext i32 (ptr, ...) @printf(ptr noundef @.str)
ret i32 0
}
declare dso_local signext i32 @printf(ptr noundef, ...)
```
This patch also updates some test cases due to new modifiers introduced.
New test: test/MC/LoongArch/Relocations/relocations.s
Differential Revision: https://reviews.llvm.org/D132108
Following the comment's thread of D117235, I added checks for the widening + splitting case, which also causes a split with one of the resulting vectors to be empty. Due to the same issues described in that same thread, the `fixed-vectors-strided-store.ll` test is missing the widening + splitting case, while the same case in the `strided-vpload.ll` test requires to manually split the loaded vector.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D121784
Adds a builtin that serves as an optimization hint to apply specific optimized
DAG mutations during scheduling. This also disables any other mutations or
clustering that may interfere with the desired pipeline. The first optimization
strategy that is added here is designed to improve the performance of small gemm
kernels on gfx90a.
Reviewed By: jrbyrnes
Differential Revision: https://reviews.llvm.org/D132079
This patch enables expansion or custom lowering for some integer
condition codes so that any xori that is needed is created before
the last DAG combine to enable optimization.
I've seen cases where we end up with
(or (xori (setcc), 1), (xori (setcc), 1)) which we would ideally
convert to (xori (and (setcc), (setcc)), 1). This patch doesn't
accomplish that yet, but it should allow us to add DAG
combines as follow ups. Example https://godbolt.org/z/Y4qnvsq1b
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D131729
SDNode.
How:
1) Add AArch64ISD::PMULL SDNode, and extend aarch64_neon_pmull intrinsic
tablegen pattern for this SDNode.
2) For aarch64_neon_pmull64, canonicalize i64 operands to v1i64 vectors
during legalization.
3) For {aarch64_neon_pmull, aarch64_neon_pmull64}, combine intrinsic to
SDNode.
Why
1) Adding the SDNode makes it easier to canonicalize i64 inputs (required by
aarch64_neon_pmull64) to vector inputs. Vector inputs carries lane
information, which helps dag-combiner to combine nodes (e.g. rewrite to a
better node to prepare for instruction selection) and instruction-selection
to emit instructions that use higher-half inputs in place
(i.e., no need to move lane 1 content to lane 0).
2) Using the SDNode for aarch64_neon_pmull64 is NFC, yet without this we
have to move the definition of {PMULLv1i64, PMULLv2i64} out of its
current group of records without gains.
Test cases are commented with what is being tested in
`aarch64-pmull2.ll` and `pmull-ldr-merge.ll` under directory
`llvm/test/CodeGen/AArch64`.
Differential Revision: https://reviews.llvm.org/D131047
Certain address space dependent optimizations, like SeperateConstOffsetFromGEP, assume agreement between the address space of the recursive uses and the address space of the def. If this assumption is invalid, then optimizations may or may not be correct depending on properties of an address space for a given target, the address spaces of recursive uses, and the optimization being done.
This patch infers the previous address space for flat_atomic ptr arguments. As a result, the address spaces of the uses in flat_atomic cases will agree with the address space in recursive defs. If this results in non-flat address space, then isel may infer a different intrinsic. For example, if the result is a flat_atomic using global address space, then it will be lowered to the corresponding global_atomic intrinsic.
Change-Id: Ifcd981709dc2ea94d4acbcb84efe7176593ec8c7
Use it to the fix a bug in the fceil/ffloor lowerings. We were
setting the passthru to IMPLICIT_DEF before and using a mask
agnostic policy. This means where the incoming bits in
the mask were 0 they could be anything in the outgoing mask. We
want those bits in the outgoing mask to be 0. This means we need to
pass the input mask as the passthru.
This generates worse code because we are unable to allocate the
v0 register to the output due to an earlyclobber constraint. We
probably need a special TIED pseudoinstruction and probably custom
isel since you can't use V0 twice in the input pattern.
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D132058
I have a couple data points that some microarchitectures prefer
the immediate 0 over x0. Does anyone know of microarchitectures
where the opposite is true?
Unfortunately, this is different than the vncvt.x.x.w alias
from the spec. Perhaps the alias was poorly chosen if x0 isn't
as optimal as immediate 0 on all microarchitectures.
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D132041
This patch fixes the following two bugs in `PPCInstrInfo::isSignOrZeroExtended` helper, which is used from sign-/zero-extension elimination in PPCMIPeephole pass.
- Registers defined by load with update (e.g. LBZU) were identified as already sign or zero-extended. But it is true only for the first def (loaded value) and not for the second def (i.e. updated pointer).
- Registers defined by ORIS/XORIS were identified as already sign-extended. But, it is not true for sign extension depending on the immediate (while it is ok for zero extension).
To handle the first case, the parameter for the helpers is changed from `MachineInstr` to a register number to distinguish first and second defs. Also, this patch moves the initialization of PPCMIPeepholePass to allow mir test case.
Reviewed By: nemanjai
Differential Revision: https://reviews.llvm.org/D40554
This change adds support for lowering llvm.prefetch directly using
GlobalISel. Currently, llvm.prefetch falls back to SelectionDAG.
This Change:
- Adds an AArch64-specific G_PREFETCH generic instruction, to be used
where AArch64ISD::PREFETCH is used in SelectionDAG.
- Adds the GINodeEquiv so patterns are translated over to GlobalISel
automatically.
- Corrects the AArch64Prefetch patterns to use a target immediate, which
is needed to get the patterns to translate across correctly.
- Translates the SelectionDAG legalisation of the prefetch intrinsic
into the corresponding GlobalISel legalisation.
Differential Revision: https://reviews.llvm.org/D132043
The current llvm.prefetch intrinsic docs state "The rw, locality and
cache type arguments must be constant integers."
This change:
- Makes arg 3 (cache type) an ImmArg
- Improves the verifier error messages to reference the incorrect
argument.
- Fixes two tests which contradict the docs.
This is needed as the lowering to GlobalISel is different for ImmArgs
compared to other constants. The non-ImmArgs create a G_CONSTANT MIR
instruction, the for ImmArgs the constant is put directly on the
intrinsic's MIR instruction as an immediate.
Differential Revision: https://reviews.llvm.org/D132042
Currently, record arguments are always passed by reference by allocating
space for record values in the caller. This is less efficient for
small records which may take one or two registers. For example,
for x86_64 and aarch64, for a record size up to 16 bytes, the record
values can be passed by values directly on the registers.
This patch added BPF support of record argument with direct values
for up to 16 byte record size. If record size is 0, that record
will not take any register, which is the same behavior for x86_64
and aarch64. If the record size is greater than 16 bytes, the
record argument will be passed by reference.
Differential Revision: https://reviews.llvm.org/D132144
AdrpAdd fusion is already enabled for "generic" and it helps
the linker apply relocation relaxations for more adrp+add pairs.
This patch enables it for -mtune=neoverse-n1.
Differential revision: https://reviews.llvm.org/D132075
Extends findMoreOptimalIndexType to allow ISD::BUILD_VECTOR based
indices to be truncated when such truncation is lossless. This can
enable the use of 32bit gather/scatter indices thus making it less
likely to have to split a gather/scatter in two.
Depends on D125194
Differential Revision: https://reviews.llvm.org/D130533
Specifying `-regalloc=fast` is not reliable. With fast register allocation,
`LIS = getAnalysisIfAvailable<LiveIntervals>();` get nullptr
in "si-lower-sgpr-spills" pass, so the slot index is not created in the
pass for new inserted instructions. When verifying the machine
instructions, it fails on checking slot index. While greedy-ra is time
consuming basic-ra can be used to reduce compiling time for this test case.
Differential Revision: https://reviews.llvm.org/D131931
Requested SchedGroup pipelines may be non-trivial to satisify. A minimimal example is if the requested pipeline is {2 VMEM, 2 VALU, 2 VMEM} and the original order of SUnits is {VMEM, VALU, VMEM, VALU, VMEM}. Because of existing dependencies, the choice of which SchedGroup the middle VMEM goes into impacts how closely we are able to match the requested pipeline. It seems minimizing the degree of misfit (as measured by the number of edges we can't add) w.r.t the choice we make when mapping an instruction -> SchedGroup is an NP problem. This patch implements the PipelineSolver class which produces a solution for the defined problem for the sched_group_barrier mutation. The solver has both an exponential time exact algorithm and a greedy algorithm. The patch includes some controls which allows the user to select the greedy/exact algorithm.
Differential Revision: https://reviews.llvm.org/D130797
This is a potentially better alternative to D131452 that also
should avoid the infinite loop bug from:
issue #56403
This is again a minimal fix to reduce merging pain for the
release. But if this makes sense, then we might want to guard
all of the RTLIB generation (and other libcalls?) with a
similar name check.
Differential Revision: https://reviews.llvm.org/D131521
Improve copy statistics:
- Count copies from or to physical registers: They are used to model function parameters and calling conventions and the register allocator optimizes for them.
- Check physical registers assigned to virtual registers and stop counting "identity" `COPY`s where source and destination is the same physical registers; they will be removed in the `virtregmap` pass anyway.
Differential Revision: https://reviews.llvm.org/D131932
The current machine function splitter is reliant on profile data to do profile summary analysis to split blocks into cold section. This may sometimes limit the usage of machine function splitter especially in cases where we could do some form of static analysis to split out cold blocks if profile data is absent or profile data which may be faulty (Consider Sample PGO).
Of all code that could statically be marked cold Exception handling blocks are one of them (In fact BFI framework also tends to mark them as cold), and the most in size contribution. In my experiments I found out Exception handling pads and all code reachable from there account for up to 6-8% of the .text section on modern production binaries. This patch introduces a flag to split out all Exception handling blocks and blocks only reachable from Exceptional Handling pad to cold section. This flag has shown to give a performance win of up to 0.1% in terms of average cycles and instructions executed on internal facebook search service.
Reviewed By: snehasish
Differential Revision: https://reviews.llvm.org/D131824
Extracted from D131729 where we handled C==0. It's now generalized
to more constants.
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D132000
