Similar to 806761a7629df268c8aed49657aeccffa6bca449
-mtriple= specifies the full target triple while -march= merely sets the
architecture part of the default target triple (e.g. Windows, macOS),
leaving a target triple which may not make sense.
Therefore, -march= is error-prone and not recommended for tests without a target
triple. The issue has been benign as we recognize sparc*-apple-darwin as ELF instead
of rejecting it outrightly.
SPARC ABI doesn't use stack realignment, so let LLVM know about it in
`SparcFrameLowering`. This has the side effect of making all overaligned
allocations go through `LowerDYNAMIC_STACKALLOC`, so implement the
missing logic there too for overaligned allocations.
This makes the SPARC backend not crash on overaligned `alloca`s and fix
https://github.com/llvm/llvm-project/issues/89569.
The previous behavior could be harmful in some edge cases, such as
emitting a call to `fma()` in the `fma()` implementation itself.
Do this by just being more accurate in `isFMAFasterThanFMulAndFAdd()`.
This was already done for PowerPC; this commit just extends that to Arm,
z/Arch, and x86. MIPS and SPARC already got it right, but I added tests
for them too, for good measure.
Note: I don't have commit access.
Some targets (e.g. PPC and Hexagon) already did this. I think it's best
to do this consistently so that frontend authors don't run into
inconsistent results when they emit `naked` functions. For example, in
Zig, we had to change our emit code to also set `frame-pointer=none` to
get reliable results across targets.
Note: I don't have commit access.
This patch adds a pass that provides workarounds for the errata
described in GRLIB-TN-0009, GRLIB-TN-0010, GRLIB-TN-0011, GRLIB-TN-0012,
and GRLIB-TN-0013, that are applicable to the GR712RC and UT700. The
documents are available for download from here:
https://www.gaisler.com/index.php/information/app-tech-notes
The pass will detect certain sensitive instruction sequences and prevent
them from occurring by inserting NOP instruction. Below is an overview
of each of the workarounds. A similar implementation is available in
GCC.
GRLIB-TN-0009:
* Insert NOPs to prevent the sequence (stb/sth/st/stf) -> (single
non-store/load instruction) -> (any store)
* Insert NOPs to prevent the sequence (std/stdf) -> (any store)
GRLIB-TN-0010:
* Insert a NOP between load instruction and atomic instruction (swap and
casa).
* Insert a NOP at branch target if load in delay slot and atomic
instruction at branch target.
* Do not allow functions to begin with atomic instruction.
GRLIB-TN-0011:
* Insert .p2align 4 before atomic instructions (swap and casa).
GRLIB-TN-0012:
* Place a NOP at the branch target of an integer branch if it is a
floating-point operation or a floating-point branch.
GRLIB-TN-0013:
* Prevent (div/sqrt) instructions in the delay slot.
* Insert NOPs to prevent the sequence (div/sqrt) -> (two or three
floating point operations or loads) -> (div/sqrt).
* Do not insert NOPs if any of the floating point operations have a
dependency on the destination register of the first (div/sqrt).
* Do not insert NOPs if one of the floating point operations is a
(div/sqrt).
* Insert NOPs to prevent (div/sqrt) followed by a branch.
This adds support for using the L and H argument modifiers for twinword
operands in inline asm code, such as in:
```
%1 = tail call i64 asm sideeffect "rd %pc, ${0:L} ; srlx ${0:L}, 32, ${0:H}", "={o4}"()
```
This is needed by the Linux kernel.
When in 32-bit mode, the backend doesn't currently implement 64-bit
atomics, even though the hardware is capable if you have specified a V9
CPU. Thus, limit the width to 32-bit, for now, leaving behind a TODO.
This fixes a regression triggered by PR #73176.
This adds support for marking arbitrary general purpose registers -
except for those with special purpose (G0, I6-I7, O6-O7) - as reserved,
as needed by some software like the Linux kernel.
On 64-bit target, prefer using RDPC over CALL to get the value of %pc.
This is faster on modern processors (Niagara T1 and newer) and avoids
polluting the processor's predictor state.
The old behavior of using a fake CALL is still done when tuning for
classic UltraSPARC processors, since RDPC is much slower there.
A quick pgbench test on a SPARC T4 shows about 2% speedup on SELECT
loads, and about 7% speedup on INSERT/UPDATE loads.
Reviewed By: @s-barannikov
Github PR: https://github.com/llvm/llvm-project/pull/78280
* Placing 'G' before 'M' (SHF_MERGE) can be misleading as the sh_entsize
argument goes before the section group name, if a reader doesn't know
that the order of extra arguments is not affected by the order of flags.
* 'a', 'w', and 'x' indicate basic permission-related flags. Separating
them with 'G' is kinda ugly.
Simplify code and move 'G' after 'o'. The new output is more similar to
GCC.
There are no 64-bit variants of these ALU / SETHI instructions in V9.
Remove these instruction definitions and add patterns to match DAG nodes
to the generic instructions defined in SparcInstrInfo.td.
This is not strictly NFC because of the changes in
`2011-01-11-FrameAddr.ll` test. The reason is that Sparc delay slot
filler pass handled ADDrr but not ADDXrr, which are now the same
instruction.
PR #66334 tried to renumber slot indexes before register allocation, but
the numbering was still affected by list entries for instructions which
had been erased. Fix this to make the register allocator's live range
length heuristics even less dependent on the history of how instructions
have been added to and removed from SlotIndexes's maps.
LEA_ADDri and LEAX_ADDri are printed / encoded the same way as ADDri. I
had to change the type of simm13Op so that it can be used in both 32-
and 64-bit modes. This required the changes in operands of some
InstAliases.
RegAllocGreedy uses SlotIndexes::getApproxInstrDistance to approximate
the length of a live range for its heuristics. Renumbering all slot
indexes with the default instruction distance ensures that this estimate
will be as accurate as possible, and will not depend on the history of
how instructions have been added to and removed from SlotIndexes's maps.
This also means that enabling -early-live-intervals, which runs the
SlotIndexes analysis earlier, will not cause large amounts of churn due
to different register allocator decisions.
LLVM fails to build on 32-bit Solaris/SPARC: several programs fail to
link due to undefined references to `__multi3`. This reference is from
`lib/libLLVMScalarOpts.a(LoopStrengthReduce.cpp.o)`. However, This
function exists neither in the 32-bit `libgcc.a` nor in
`libclang_rt.builtins-sparc.a`. It's only defined in their 64-bit
counterparts.
The same issue affects several 32-bit targets, e.g. 32-bit PowerPC as
described in Issue #54460. The fix is the same: inhibit the libcall for
32-bit compilations. This patch does just that, regenerating the
affected testcases. It allows the build to complete.
Tested on `sparc-sun-solaris2.11`.
The issue is uncovered by #47698: for IR files without a target triple,
-mtriple= specifies the full target triple while -march= merely sets the
architecture part of the default target triple, leaving a target triple which
may not make sense, e.g. riscv64-apple-darwin.
Therefore, -march= is error-prone and not recommended for tests without a target
triple. The issue has been benign as we recognize $unknown-apple-darwin as ELF instead
of rejecting it outrightly.
We currently don't extract vector elements from multi-use build vectors unless TLI.aggressivelyPreferBuildVectorSources accepts them, which seems a little extreme for constant build vectors (especially as under some cases ComputeKnownBits will indirectly extract the data for us).
This is causing a few regressions in some upcoming SimplifyDemandedBits work I'm looking at, all of which just need to know that the element is zero, so I've tweaked the fold to accept zero elements as well, which will typically fold very easily.
Differential Revision: https://reviews.llvm.org/D155582
This is a follow-up to b71edfaa4ec3c998aadb35255ce2f60bba2940b0
since I forgot the lit.local.cfg files in that one.
Reformatting is done with `black`.
If you end up having problems merging this commit because you
have made changes to a python file, the best way to handle that
is to run git checkout --ours <yourfile> and then reformat it
with black.
If you run into any problems, post to discourse about it and
we will try to help.
RFC Thread below:
https://discourse.llvm.org/t/rfc-document-and-standardize-python-code-style
Reviewed By: barannikov88, kwk
Differential Revision: https://reviews.llvm.org/D150762
On 64-bit target, when doing i64 BR_CC where one of the comparison operands is a
constant zero, try to fold the compare and BPcc into a BPr instruction.
For all integers, EQ and NE comparison are available, additionally for signed
integers, GT, GE, LT, and LE is also available.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D142461
On 64-bit target, when doing i64 BR_CC where one of the comparison operands is a
constant zero, try to fold the compare and BPcc into a BPr instruction.
For all integers, EQ and NE comparison are available, additionally for signed
integers, GT, GE, LT, and LE is also available.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D142461
Integrate the BranchRelaxation pass to help with relaxing out-of-range
conditional branches.
This is mostly of concern for SPARCv9, which uses conditional branches with
much smaller range than its v8 counterparts.
(Some large autogenerated code, such as the ones generated by TableGen, already
hits this limitation when building in Release)
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D142458
These are essentially add/sub 1 with a clamping value.
AMDGPU has instructions for these. CUDA/HIP expose these as
atomicInc/atomicDec. Currently we use target intrinsics for these,
but those do no carry the ordering and syncscope. Add these to
atomicrmw so we can carry these and benefit from the regular
legalization processes.
In LowerSELECT_CC, SELECT_REG between two f128s should only be emitted if we
have hardware quadfloat enabled.
This should fix issue #59646
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D140515
Materialize zeros by copying from %g0, which is now marked as constant.
This makes it possible for some common operations (like integer negation) to be
performed in fewer instructions.
This continues @arichardson's patch at D132561.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D138887
On 64-bit target, when doing i64 SELECT_CC where one of the comparison operands
is a constant zero, try to fold the compare and MOVcc into a MOVr instruction.
For all integers, EQ and NE comparison are available, additionally for signed
integers, GT, GE, LT, and LE is also available.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D138922
Materialize zeros by copying from %g0, which is now marked as constant.
This makes it possible for some common operations (like integer negation) to be
performed in fewer instructions.
This continues @arichardson's patch at D132561.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D138887
Don't emit deprecated v8-style FP compares & branches when targeting v9
processors.
For now, always use %fcc0, because currently the allocator requires allocatable
registers to also be spillable, which isn't the case with v9 FCC registers.
The work to enable allocation over the entire FCC register file will be done in
a future patch.
Fixes bug #17834
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D135515
Do not emit deprecated v8-style branches when targeting a v9 processor.
As a side effect, this also fixes the emission of useless ba's when doing
conditional branches on 64-bit integer values.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D130006
Implement CanLowerReturn and associated CallingConv changes for SPARC/SPARC64.
In particular, for SPARC64 there's new `RetCC_Sparc64_*` functions that handles the return case of the calling convention.
It uses the same analysis as `CC_Sparc64_*` family of funtions, but fails if the return value doesn't fit into the return registers.
This makes calls to functions with big return values converted to an sret function as expected, instead of crashing LLVM.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D132465
The code incorrectly checked for CTLZ_ZERO_UNDEF instead of
CTTZ_ZERO_UNDEF.
While I was there I flipped the condition into an early out.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D136010
As discussed in D85414 <https://reviews.llvm.org/D85414>, two tests
currently `FAIL` on Sparc since that backend uses the Sun assembler syntax
for the `.section` directive, controlled by
`SunStyleELFSectionSwitchSyntax`.
Instead of adapting the affected tests, this patch changes that default.
The internal assembler still accepts both forms as input, only the output
syntax is affected.
Current support for the Sun syntax is cursory at best: the built-in
assembler cannot even assemble some of the directives emitted by GCC, and
the set supported by the Solaris assembler is even larger: SPARC Assembly
Language Reference Manual, 3.4 Pseudo-Op Attributes
<https://docs.oracle.com/cd/E37838_01/html/E61063/gmabi.html#scrolltoc>.
A few Sparc test cases need to be adjusted. At the same time, the patch
fixes the failures from D85414 <https://reviews.llvm.org/D85414>.
Tested on `sparcv9-sun-solaris2.11`.
Differential Revision: https://reviews.llvm.org/D85415
This patch emits table lookup in expandCTTZ.
Context -
https://reviews.llvm.org/D113291 transforms set of IR instructions to
cttz intrinsic but there are some targets which does not support CTTZ or
CTLZ. Hence, I generate a table lookup in TargetLowering::expandCTTZ().
Differential Revision: https://reviews.llvm.org/D128911