This patch does a few things to start cleaning up the isFNEG function.
-Remove the Op0/Op1 peekThroughBitcast calls that seem unnecessary. getTargetConstantBitsFromNode has its own peekThroughBitcast inside. And we have a separate peekThroughBitcast on the return value.
-Add a check of the scalar size after the first peekThroughBitcast to ensure we haven't changed the element size and just did something like f32->i32 or f64->i64.
-Remove an unnecessary check that Op1's type is floating point after the peekThroughBitcast. We're just going to look for a bit pattern from a constant. We don't care about its type.
-Add VT checks on several places that consume the return value of isFNEG. Due to the peekThroughBitcasts inside, the type of the return value isn't guaranteed. So its not safe to use it to build other nodes without ensuring the type matches the type being used to build the node. We might be able to replace these checks with bitcasts instead, but I don't have a test case so a bail out check seemed better for now.
Differential Revision: https://reviews.llvm.org/D63683
llvm-svn: 364206
This needs different handling if the source is known to be a valid
condition or not. Handle turning it into shifts or a select during
regbankselect.
llvm-svn: 364186
This matters for byval uses outside of the entry block, which appear
as copies.
Previously, the only folding done was during selection, which could
not see the underlying frame index. For any uses outside the entry
block, the frame index was materialized in the entry block relative to
the global scratch wave offset.
This may produce worse code in cases where the offset ends up not
fitting in the MUBUF offset field. A better heuristic would be helpfu
for extreme frames.
llvm-svn: 364185
This can occur under certain circumstances when undefs are created later on in the constant multipliers (e.g. in this case due to SimplifyDemandedVectorElts). Its better to let the shift by zero to occur and perform any cleanup afterward.
Fixes OSS Fuzz #15429
llvm-svn: 364179
Ideally we'd be able to represent this truncate as a any_extend to
v16i32 and a truncate, but SelectionDAG doens't know how to not
fold those together.
We have isel patterns to use a vpmovzxwd+vpdmovdb for the truncate,
but we aren't able to simultaneously fold the load and the store
from the isel pattern. By pulling the truncate into the store we
can successfully hide it from the DAG combiner. Then we can isel
pattern match the truncstore and load+any_extend separately.
llvm-svn: 364163
This is useful for allowing code to efficiently take an address
that can be later mapped onto debug info. Currently the hwasan
pass achieves this by taking the address of the current function:
http://llvm-cs.pcc.me.uk/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp#921
but this costs two instructions (plus a GOT entry in PIC code) per function
with stack variables. This will allow the cost to be reduced to a single
instruction.
Differential Revision: https://reviews.llvm.org/D63471
llvm-svn: 364126
To help produce better diagnostics for stack use-after-return, we'd like
to be able to determine the addresses of each HWASANified function's local
variables given a small amount of information recorded on entry to the
function. Currently we require all HWASANified functions to use frame pointers
and record (PC, FP) on function entry. This works better than recording SP
because FP cannot change during the function, unlike SP which can change
e.g. due to dynamic alloca.
However, most variables currently end up using SP-relative locations in their
debug info. This prevents us from recomputing the address of most variables
because the distance between SP and FP isn't recorded in the debug info. To
address this, make the AArch64 backend prefer FP-relative debug locations
when producing debug info for HWASANified functions.
Differential Revision: https://reviews.llvm.org/D63300
llvm-svn: 364117
On Windows ARM64, intrinsic __debugbreak is compiled into brk #0xF000 which is
mapped to llvm.debugtrap in Clang. Instruction brk #F000 is the defined break
point instruction on ARM64 which is recognized by Windows debugger and
exception handling code, so llvm.debugtrap should map to it instead of
redirecting to llvm.trap (brk #1) as the default implementation.
Differential Revision: https://reviews.llvm.org/D63635
llvm-svn: 364115
128/256 bit scalar_to_vectors are canonicalized to (insert_subvector undef, (scalar_to_vector), 0). We have isel patterns that try to match this pattern being used by a vzmovl to use a 128-bit instruction and a subreg_to_reg.
This patch detects the insert_subvector undef portion of this and pulls it through the vzmovl, creating a narrower vzmovl and an insert_subvector allzeroes. We can then match the insertsubvector into a subreg_to_reg operation by itself. Then we can fall back on existing (vzmovl (scalar_to_vector)) patterns.
Note, while the scalar_to_vector case is the motivating case I didn't restrict to just that case. I'm also wondering about shrinking any 256/512 vzmovl to an extract_subvector+vzmovl+insert_subvector(allzeros) but I fear that would have bad implications to shuffle combining.
I also think there is more canonicalization we can do with vzmovl with loads or scalar_to_vector with loads to create vzload.
Differential Revision: https://reviews.llvm.org/D63512
llvm-svn: 364095
With this we can now fully code generate jump tables, which is important for code size.
Differential Revision: https://reviews.llvm.org/D63223
llvm-svn: 364086
This change makes use of the newly refactored SwitchLoweringUtils code from
SelectionDAG to in order to generate jump tables and range checks where appropriate.
Much of this code is ported from SDAG with some modifications. We generate
G_JUMP_TABLE and G_BRJT instructions when JT opportunities are found. This means
that targets which previously relied on the naive one MBB per case stmt
translation will now start falling back until they add support for the new opcodes.
For range checks, we don't generate any previously unused operations. This
just recognizes contiguous ranges of case values and generates a single block per
range. Single case value blocks are just a special case of ranges so we get that
support almost for free.
There are still some optimizations missing that I haven't ported over, and
bit-tests are also unimplemented. This patch series is already complex enough.
Actual arm64 support for selection of jump tables is coming in a later patch.
Differential Revision: https://reviews.llvm.org/D63169
llvm-svn: 364085
We already use vmovq for v2i64/v2f64 vzmovl. But we were using a
blendpd+xorpd for v4i64/v4f64/v8i64/v8f64 under opt speed. Or
movsd+xorpd under optsize.
I think the blend with 0 or movss/d is only needed for
vXi32 where we don't have an instruction that can move 32
bits from one xmm to another while zeroing upper bits.
movq is no worse than blendpd on any known CPUs.
llvm-svn: 364079
We sometimes get poor code size because constants of types < 32b are legalized
as 32 bit G_CONSTANTs with a truncate to fit. This works but means that the
localizer can no longer sink them (although it's possible to extend it to do so).
On AArch64 however s8 and s16 constants can be selected in the same way as s32
constants, with a mov pseudo into a W register. If we make s8 and s16 constants
legal then we can avoid unnecessary truncates, they can be CSE'd, and the
localizer can sink them as normal.
There is a caveat: if the user of a smaller constant has to widen the sources,
we end up with an anyext of the smaller typed G_CONSTANT. This can cause
regressions because of the additional extend and missed pattern matching. To
remedy this, there's a new artifact combiner to generate the wider G_CONSTANT
if it's legal for the target.
Differential Revision: https://reviews.llvm.org/D63587
llvm-svn: 364075
Summary:
LLVM Allows Targets to provide information that guides optimisations
made to LLVM IR. This is done with callbacks on a TargetTransformInfo object.
This patch adds a TargetTransformInfo class for RISC-V. This will allow us to
implement RISC-V specific callbacks as they become necessary.
This commit also adds the getIntImmCost callbacks, and tests them with a simple
constant hoisting test. Our immediate costs are on the conservative side, for
the moment, but we prevent hoisting in most circumstances anyway.
Previous review was on D63007
Reviewers: asb, luismarques
Reviewed By: asb
Subscribers: ributzka, MaskRay, llvm-commits, Jim, benna, psnobl, jocewei, PkmX, rkruppe, the_o, brucehoult, MartinMosbeck, rogfer01, edward-jones, zzheng, jrtc27, shiva0217, kito-cheng, niosHD, sabuasal, apazos, simoncook, johnrusso, rbar, hiraditya, mgorny
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63433
llvm-svn: 364046
The sat add/sub tests still have unnecessary extract_subvector((vandnps ymm, ymm), 0) uses that should be split to (vandnps (extract_subvector(ymm, 0), extract_subvector(ymm, 0)), but its getting better.
llvm-svn: 364038
G_INTTOPTR can prevent the localizer from moving G_CONSTANTs, but since it's
essentially a side effect free cast instruction we can remat both instructions.
This patch changes the localizer to enable localization of the chains by
iterating over the entry block instructions in reverse order. That way, uses will
localized first, and then the defs are free to be localized as well.
This also changes the previous SmallPtrSet of localized instructions to use a
SetVector instead. We're dealing with pointers and need deterministic iteration
order.
Overall, this change improves ARM64 -O0 CTMark code size by around 0.7% geomean.
Differential Revision: https://reviews.llvm.org/D63630
llvm-svn: 364001
Every called function could possibly need this to calculate the
absolute address of stack objectst, and this avoids inserting a copy
around every call site in the kernel. It's also somewhat cleaner to
keep this in a callee saved SGPR.
llvm-svn: 363990
Summary:
BLSI sets the C flag is the input is not zero. So if its followed
by a TEST of the input where only the Z flag is consumed, we can
replace it with the opposite check of the C flag.
We should be able to do the same for BLSMSK and BLSR, but the
naive test case for those is being optimized to a subo by
CodeGenPrepare.
Reviewers: spatel, RKSimon
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63589
llvm-svn: 363957
The attribute can specify elimination for leaf or non-leaf, so it
should always be considered. I copied this bug from AArch64, which
probably should also be fixed.
llvm-svn: 363949
Introducing VCC defs during SIFixSGPRCopies is generally
problematic. Avoid it by starting with the VOP3 form with the general
condition register. This is the easiest to fix instance, but doesn't
solve any specific problems I'm looking at.
llvm-svn: 363904
The ARMDisassembler changes allow changing between ARM and Thumb mode
based on the MCSubtargetInfo, rather than the Target, which simplifies
the other changes a bit.
I'm not really happy with adding more target-specific logic to
tools/llvm-objdump/, but there isn't any easy way around it: the logic
in question specifically applies to disassembling an object file, and
that code simply isn't located in lib/Target, at least at the moment.
Differential Revision: https://reviews.llvm.org/D60927
llvm-svn: 363903
Craig Topper