I found a really strange WWM issue through a very convoluted shader that
essentially boils down to a bug in SIInstrInfo where canReadVGPR did not
correctly identify that WWM is like a copy and can have a VGPR as its
source.
Differential Revision: https://reviews.llvm.org/D56002
llvm-svn: 352500
Re-enable the code to rewrite main-function signatures into
"int main(int argc, char *argv[])", but limited to only handling
the case of "int main(void)", so that it doesn't silently strip
an argument in the "int main(int argc, char *argv[], char *envp[])"
case.
This allows main to be called by C startup code, since WebAssembly
requires caller and callee signatures to match, so it can't rely
on passing main a different number of arguments than it expects.
Differential Revision: https://reviews.llvm.org/D57323
llvm-svn: 352479
This attempts to optimise negative values used in load/store operands
a little. We currently try to selct them as rr, materialising the
negative constant using a MOV/MVN pair. This instead selects ri with
an immediate of 0, forcing the add node to become a simpler sub.
Differential Revision: https://reviews.llvm.org/D57121
llvm-svn: 352475
Windows ARM64 has PIC relocation model and uses jump table kind
EK_LabelDifference32. This produces jump table entry as
".word LBB123 - LJTI1_2" which represents the distance between the block
and jump table.
A new relocation type (IMAGE_REL_ARM64_REL32) is needed to do the fixup
correctly if they are in different COFF section.
This change saves the jump table to the same COFF section as the
associated code. An ideal fix could be utilizing IMAGE_REL_ARM64_REL32
relocation type.
Patch by Tom Tan!
Differential Revision: https://reviews.llvm.org/D57277
llvm-svn: 352465
Without the fix we get the following (with -Werror):
../lib/Target/X86/X86ISelLowering.cpp:14181:58: error: suggest braces around initialization of subobject [-Werror,-Wmissing-braces]
SmallVector<std::array<int, 2>, 2> LaneSrcs(NumLanes, {-1, -1});
^~~~~~
{ }
1 error generated.
llvm-svn: 352455
Previously we were only handling bitcast operations, however
prototypeless functions can also appear in other places such as
comparisons and as function params.
Switch to using replaceAllUsesWith() to replace the prototype-less
function uses. This new approach results in some redundant bitcasting
but is much simpler and handles all cases.
Differential Revision: https://reviews.llvm.org/D56938
llvm-svn: 352445
Move the CC analysis implementation to its own .cpp file instead of
duplicating it and artificually using functions in PPCISelLowering.cpp
and PPCFastISel.cpp. Follow-up to the same change done for X86, ARM, and
AArch64.
llvm-svn: 352444
This did not cause the buildbot failure it was previously reverted for.
Original commit message:
I'm not sure why we were using SEXTLOAD. EXTLOAD seems more appropriate since we don't care about the upper bits.
This patch changes this and then modifies the X86 post legalization combine to emit a extending shuffle instead of a sign_extend_vector_inreg. Could maybe use an any_extend_vector_inre
On AVX512 targets I think we might be able to use a masked vpmovzx and not have to expand this at all.
llvm-svn: 352433
Summary:
Avoids duplicating generated static helpers for calling convention
analysis.
This also means you can modify AArch64CallingConv.td without recompiling
the AArch64ISelLowering.cpp monolith, so it provides faster incremental
rebuilds.
Saves 12K in llc.exe, but adds a new object file, which is large.
Reviewers: efriedma, t.p.northover
Subscribers: mgorny, javed.absar, kristof.beyls, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D56948
llvm-svn: 352430
This adds support for legalizing G_FLOG into a RTLib call.
It adds a legalizer test, and updates the existing floating point tests.
https://reviews.llvm.org/D57347
llvm-svn: 352429
Since these pass the pointer in m0 unlike other DS instructions, these
need to worry about whether the address is uniform or not. This
assumes the address is dynamically uniform, and just uses
readfirstlane to get a copy into an SGPR.
I don't know if these have the same 16-bit add for the addressing mode
offset problem on SI or not, but I've just assumed they do.
Also includes some misc. changes to avoid test differences between the
LDS and GDS versions.
llvm-svn: 352422
This adds instruction selection support for @llvm.log10 in AArch64. It teaches
GISel to lower it to a library call, updates the relevant tests, and adds a
legalizer test for log10.
https://reviews.llvm.org/D57341
llvm-svn: 352418
The 'apple-latest' alias is supposed to provide a CPU that contains the
latest Apple processor model supported by LLVM.
This is supposed to be used by tools like lldb to provide a target that
supports most of the CPU features.
For now, this is mapped to Cyclone.
Differential Revision: https://reviews.llvm.org/D56384
llvm-svn: 352412
Followup to D56636, this time handling the UADDSAT case by expanding
uadd.sat(a, b) to umin(a, ~b) + b.
Differential Revision: https://reviews.llvm.org/D56869
llvm-svn: 352409
This contains all of the legalizer changes from D57197 necessary to select
G_FCOS and G_FSIN. It also updates several existing IR tests in
test/CodeGen/AArch64 that verify that we correctly lower the G_FCOS and G_FSIN
instructions.
https://reviews.llvm.org/D57197
3/3
llvm-svn: 352402
First step towards adding support for 64-bit unary "sublane" handling (a bit like lowerShuffleAsRepeatedMaskAndLanePermute).
This allows us to add lowerV64I8Shuffle handling.
llvm-svn: 352389
This is tricky to make optimal: sometimes we're better off using
a single wider op, but other times it makes more sense to combine
a narrow ops to achieve the same result.
This solves the case from:
https://bugs.llvm.org/show_bug.cgi?id=40434
There's potentially a similar change for vectors with 64-bit elements,
but it needs adjustments similar to rL352333 to avoid creating infinite
loops.
llvm-svn: 352380
As the codebase is now under the Apache 2.0 license with LLVM
Exceptions, and all Arm's contributions, past or future, are under that
new license, this Arm specific LICENSE.TXT is no longer needed, thus
removing it.
llvm-svn: 352376
Instruction abs.[ds] is not generating correct result when working
with NaNs for revisions prior mips32r6 and mips64r6.
To generate a sequence which always produce a correct result, but also
to allow user more control on how his code is compiled, attribute
+abs2008 is added, so user can choose legacy or 2008.
By default legacy mode is used on revisions prior R6. Mips32r6 and
mips64r6 use abs2008 mode by default.
Differential Revision: https://reviews.llvm.org/D35983
llvm-svn: 352370
Lower G_USUBO and G_USUBE. Add narrowScalar for G_SUB.
Legalize and select G_SUB for MIPS 32.
Differential Revision: https://reviews.llvm.org/D53416
llvm-svn: 352351
Support G_SDIV, G_UDIV, G_SREM and G_UREM.
The only significant difference between arm and thumb mode is that we
need to check a different subtarget feature.
llvm-svn: 352346
This transform was added with rL351346, and we had
an escape for shufps, but we also want one for
unpckps vs. vpermps because vpermps doesn't take
an immediate shuffle index operand.
llvm-svn: 352333
Although this is longer code, this is no-functional-change-intended.
The goal is to untangle the conditions under which we bail out, so
that's easier to adjust.
llvm-svn: 352320
The add+and sequence followed by a branch can
happen e.g. when looping over the set bits of an integer:
```
while (x != 0) {
func(x & ~x);
x &= x - 1;
}
```
Reviewed By: ctopper
Differential Revision: https://reviews.llvm.org/D57296
llvm-svn: 352306
def32 here means the producing instruction zeroed bits 63:32. We already do this for zext, but it looks like we can get an and+anyext sometimes.
Spotted in the diffs from D33587.
llvm-svn: 352303
Fix issue noted in D57281 that only tested the one use for the SDValue (the result flag), not the entire SUB.
I've added the getNode() to make it clearer what is intended than just the -> redirection.
llvm-svn: 352291
As discussed on PR24545, we should try to commute X86::COND_A 'icmp ugt' cases to X86::COND_B 'icmp ult' to more optimally bind the carry flag output to a SBB instruction.
Differential Revision: https://reviews.llvm.org/D57281
llvm-svn: 352289
We often generate X86ISD::SBB(X, 0) for carry flag arithmetic.
I had tried to create test cases for the ADC equivalent (which often uses the same pattern) but haven't managed to find anything yet.
Differential Revision: https://reviews.llvm.org/D57169
llvm-svn: 352288
This reduces a bit of duplication between the combining and
lowering places that use it, but the primary motivation is
to make it easier to rearrange the lowering logic and solve
PR40434:
https://bugs.llvm.org/show_bug.cgi?id=40434
llvm-svn: 352280
For the power9 CPU, vector operations consume a pair of execution units rather
than one execution unit like a scalar operation. Update the target transform
cost functions to reflect the higher cost of vector operations when targeting
Power9.
Patch by RolandF.
Differential revision: https://reviews.llvm.org/D55461
llvm-svn: 352261
Summary: We have isel patterns for this, but we're missing some load patterns and all broadcast patterns. A DAG combine seems like a better fit for this.
Reviewers: RKSimon, spatel
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D56971
llvm-svn: 352260
Summary:
I'm not sure why we were using SEXTLOAD. EXTLOAD seems more appropriate since we don't care about the upper bits.
This patch changes this and then modifies the X86 post legalization combine to emit a extending shuffle instead of a sign_extend_vector_inreg. Could maybe use an any_extend_vector_inreg, but I just did what we already do in LowerLoad. I think we can actually get rid of this code entirely if we switch to -x86-experimental-vector-widening-legalization.
On AVX512 targets I think we might be able to use a masked vpmovzx and not have to expand this at all.
Reviewers: RKSimon, spatel
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D57186
llvm-svn: 352255
DAGCombiner::visitBITCAST will perform:
fold (bitconvert (fneg x)) -> (xor (bitconvert x), signbit)
fold (bitconvert (fabs x)) -> (and (bitconvert x), (not signbit))
As shown in double-bitmanip-dagcombines.ll, this can be advantageous. But
RV32FD doesn't use bitcast directly (as i64 isn't a legal type), and instead
uses RISCVISD::SplitF64. This patch adds an equivalent DAG combine for
SplitF64.
llvm-svn: 352247
Summary:
Currently, if an instruction with a memory operand has no debug information,
X86DiscriminateMemOps will generate one based on the first line of the
enclosing function, or the last seen debug info.
This may cause confusion in certain debugging scenarios. The long term
approach would be to use the line number '0' in such cases, however, that
brings in challenges: the base discriminator value range is limited
(4096 values).
For the short term, adding an opt-in flag for this feature.
See bug 40319 (https://bugs.llvm.org/show_bug.cgi?id=40319)
Reviewers: dblaikie, jmorse, gbedwell
Reviewed By: dblaikie
Subscribers: aprantl, eraman, hiraditya
Differential Revision: https://reviews.llvm.org/D57257
llvm-svn: 352246
We also need to combine to masked truncating with saturation stores, but I'm leaving that for a future patch.
This does regress some tests that used truncate wtih saturation followed by a masked store. Those now use a truncating store and use min/max to saturate.
Differential Revision: https://reviews.llvm.org/D57218
llvm-svn: 352230
This seems unnecessarily complicated because we gave names to
opposite polarity bools and have code comments that don't really
line up with the logic.
Step 1: remove UndefUpper and assert that it is the opposite of
UndefLower after the initial early exit.
llvm-svn: 352217
Simplify to the generic ISD::ADD/SUB if we don't make use of the result flag.
This mainly helps with ADDCARRY/SUBBORROW intrinsics which get expanded to X86ISD::ADD/SUB but could be simplified further.
Noticed in some of the test cases in PR31754
Differential Revision: https://reviews.llvm.org/D57234
llvm-svn: 352210
This isn't the final fix for our reduction/horizontal codegen, but it takes care
of a lot of the problems. After we narrow the shuffle, existing combines for
insert/extract and binops kick in, and we end up with cheaper 128-bit ops.
The avg and mul reduction tests show an existing shuffle lowering hole for
AVX2/AVX512. I think in its most minimal form this is:
https://bugs.llvm.org/show_bug.cgi?id=40434
...but we might need multiple fixes to get it right.
Differential Revision: https://reviews.llvm.org/D57156
llvm-svn: 352209
Same as ARM.
On this occasion we split some of the instruction select tests for more
complicated instructions into their own files, so we can reuse them for
ARM and Thumb mode. Likewise for the legalizer tests.
llvm-svn: 352188
Fast selection of llvm icmp and fcmp instructions is not handled well about VSX instruction support.
We'd use VSX float comparison instruction instead of non-vsx float comparison instruction
if the operand register class is VSSRC or VSFRC because i32 and i64 are mapped to VSSRC and
VSFRC correspondingly if VSX feature is opened.
If the target does not have corresponding VSX instruction comparison for some type,
just copy VSX-related register to common float register class and use non-vsx comparison instruction.
Differential Revision: https://reviews.llvm.org/D57078
llvm-svn: 352174
Follow the same custom legalisation strategy as used in D57085 for
variable-length shifts (see that patch summary for more discussion). Although
we may lose out on some late-stage DAG combines, I think this custom
legalisation strategy is ultimately easier to reason about.
There are some codegen changes in rv64m-exhaustive-w-insts.ll but they are all
neutral in terms of the number of instructions.
Differential Revision: https://reviews.llvm.org/D57096
llvm-svn: 352171
The previous DAG combiner-based approach had an issue with infinite loops
between the target-dependent and target-independent combiner logic (see
PR40333). Although this was worked around in rL351806, the combiner-based
approach is still potentially brittle and can fail to select the 32-bit shift
variant when profitable to do so, as demonstrated in the pr40333.ll test case.
This patch instead introduces target-specific SelectionDAG nodes for
SHLW/SRLW/SRAW and custom-lowers variable i32 shifts to them. pr40333.ll is a
good example of how this approach can improve codegen.
This adds DAG combine that does SimplifyDemandedBits on the operands (only
lower 32-bits of first operand and lower 5 bits of second operand are read).
This seems better than implementing SimplifyDemandedBitsForTargetNode as there
is no guarantee that would be called (and it's not for e.g. the anyext return
test cases). Also implements ComputeNumSignBitsForTargetNode.
There are codegen changes in atomic-rmw.ll and atomic-cmpxchg.ll but the new
instruction sequences are semantically equivalent.
Differential Revision: https://reviews.llvm.org/D57085
llvm-svn: 352169
This patch exploits the instructions that store a single element from a vector
to preform a (store (extract_elt)). We already have code that does this with
ISA 3.0 instructions that were added to handle i8/i16 types. However, we had
never exploited the existing ones that handle f32/f64/i32/i64 types.
Differential revision: https://reviews.llvm.org/D56175
llvm-svn: 352131
As noted in D57156, we want to check at least part of
this pattern earlier (in combining), so this will allow
the code to be shared instead of duplicated.
llvm-svn: 352127
This patch adds support for vector @llvm.ceil intrinsics when full 16 bit
floating point support isn't available.
To do this, this patch...
- Implements basic isel for G_UNMERGE_VALUES
- Teaches the legalizer about 16 bit floats
- Teaches AArch64RegisterBankInfo to respect floating point registers on
G_BUILD_VECTOR and G_UNMERGE_VALUES
- Teaches selectCopy about 16-bit floating point vectors
It also adds
- A legalizer test for the 16-bit vector ceil which verifies that we create a
G_UNMERGE_VALUES and G_BUILD_VECTOR when full fp16 isn't supported
- An instruction selection test which makes sure we lower to G_FCEIL when
full fp16 is supported
- A test for selecting G_UNMERGE_VALUES
And also updates arm64-vfloatintrinsics.ll to show that the new ceiling types
work as expected.
https://reviews.llvm.org/D56682
llvm-svn: 352113
It should be emitted when any floating-point operations (including
calls) are present in the object, not just when calls to printf/scanf
with floating point args are made.
The difference caused by this is very subtle: in static (/MT) builds,
on x86-32, in a program that uses floating point but doesn't print it,
the default x87 rounding mode may not be set properly upon
initialization.
This commit also removes the walk of the types pointed to by pointer
arguments in calls. (To assist in opaque pointer types migration --
eventually the pointee type won't be available.)
That latter implies that it will no longer consider a call like
`scanf("%f", &floatvar)` as sufficient to emit _fltused on its
own. And without _fltused, `scanf("%f")` will abort with error R6002. This
new behavior is unlikely to bite anyone in practice (you'd have to
read a float, and do nothing with it!), and also, is consistent with
MSVC.
Differential Revision: https://reviews.llvm.org/D56548
llvm-svn: 352076
Select zero extending and sign extending load for MIPS32.
Use size from MachineMemOperand to determine number of bytes to load.
Differential Revision: https://reviews.llvm.org/D57099
llvm-svn: 352038
Use CombinerHelper to combine extending load instructions.
G_LOAD combined with G_ZEXT, G_SEXT or G_ANYEXT gives G_ZEXTLOAD,
G_SEXTLOAD or G_LOAD with same type as def of extending instruction
respectively.
Similarly G_ZEXTLOAD combined with G_ZEXT gives G_ZEXTLOAD and
G_SEXTLOAD combined with G_SEXT gives G_SEXTLOAD with same type
as def of extending instruction.
Differential Revision: https://reviews.llvm.org/D56914
llvm-svn: 352037
This reapplies commit r351987 with a failed test fix. Now the test
accepts both DW_OP_GNU_push_tls_address and DW_OP_form_tls_address
opcode.
Original commit message:
```
This is a fix for a regression introduced by the rL348194 commit. In
that change new type (MEK_DTPREL) of MipsMCExpr expression was added,
but in some places of the code this type of expression considered as
unexpected.
This change fixes the bug. The MEK_DTPREL type of expression is used for
marking TLS DIEExpr only and contains a regular sub-expression. Where we
need to handle the expression, we retrieve the sub-expression and
handle it in a common way.
```
llvm-svn: 352034
After creating new PHI instructions during isel pseudo expansion, the NoPHIs
property of MF should be reset in case it was previously set.
Review: Ulrich Weigand
llvm-svn: 352030
This is a fix for a regression introduced by the rL348194 commit. In
that change new type (MEK_DTPREL) of MipsMCExpr expression was added,
but in some places of the code this type of expression considered as
unexpected.
This change fixes the bug. The MEK_DTPREL type of expression is used for
marking TLS DIEExpr only and contains a regular sub-expression. Where we
need to handle the expression, we retrieve the sub-expression and
handle it in a common way.
llvm-svn: 351987
Enable full support for the debug info. Recommit to fix the emission of
the not required closing brace.
Differential revision: https://reviews.llvm.org/D46189
llvm-svn: 351972
This patch adds a new ReadAdvance definition named ReadInt2Fpu.
ReadInt2Fpu allows x86 scheduling models to accurately describe delays caused by
data transfers from the integer unit to the floating point unit.
ReadInt2Fpu currently defaults to a delay of zero cycles (i.e. no delay) for all
x86 models excluding BtVer2. That means, this patch is only a functional change
for the Jaguar cpu model only.
Tablegen definitions for instructions (V)PINSR* have been updated to account for
the new ReadInt2Fpu. That read is mapped to the the GPR input operand.
On Jaguar, int-to-fpu transfers are modeled as a +6cy delay. Before this patch,
that extra delay was added to the opcode latency. In practice, the insert opcode
only executes for 1cy. Most of the actual latency is actually contributed by the
so-called operand-latency. According to the AMD SOG for family 16h, (V)PINSR*
latency is defined by expression f+1, where f is defined as a forwarding delay
from the integer unit to the fpu.
When printing instruction latency from MCA (see InstructionInfoView.cpp) and LLC
(only when flag -print-schedule is speified), we now need to account for any
extra forwarding delays. We do this by checking if scheduling classes declare
any negative ReadAdvance entries. Quoting a code comment in TargetSchedule.td:
"A negative advance effectively increases latency, which may be used for
cross-domain stalls". When computing the instruction latency for the purpose of
our scheduling tests, we now add any extra delay to the formula. This avoids
regressing existing codegen and mca schedule tests. It comes with the cost of an
extra (but very simple) hook in MCSchedModel.
Differential Revision: https://reviews.llvm.org/D57056
llvm-svn: 351965
Summary:
With XNACK, an smem load whose result is coalesced with an operand (thus
it overwrites its own operand) cannot appear in a clause, because some
other instruction might XNACK and restart the whole clause.
The clause breaker already realized that an smem that overwrites an
operand cannot appear in a clause, and broke the clause. The problem
that this commit fixes is that the SIFormMemoryClauses optimization
formed a bundle with early clobber, which caused the earlier code that
set up the coalesced operand to be removed as dead.
Differential Revision: https://reviews.llvm.org/D57008
Change-Id: I703c4d5b0bf7d6060222bec491f45c18bb3c0016
llvm-svn: 351950
Currently in Arm code, we allocate LR first, under the assumption that
it needs to be saved anyway. Unfortunately this has the disadvantage
that it will require any instructions using it to be the longer thumb2
instructions, not the shorter thumb1 ones.
This switches the order when we are optimising for minsize, returning to
the default order so that more lower registers can be used. It can end
up requiring more pushed registers, but on average produces smaller code.
Differential Revision: https://reviews.llvm.org/D56008
llvm-svn: 351938
In the last stage of type promotion, we replace any zext that uses a
new trunc with the operand of the trunc. This is okay when we only
allowed one type to be optimised, but now its the case that the trunc
maybe needed to produce a more narrow type than the one we were
optimising for. So we need to check this before doing the replacement.
Differential Revision: https://reviews.llvm.org/D57041
llvm-svn: 351935
As part of speculation hardening, the stack pointer gets masked with the
taint register (X16) before a function call or before a function return.
Since there are no instructions that can directly mask writing to the
stack pointer, the stack pointer must first be transferred to another
register, where it can be masked, before that value is transferred back
to the stack pointer.
Before, that temporary register was always picked to be x17, since the
ABI allows clobbering x17 on any function call, resulting in the
following instruction pattern being inserted before function calls and
returns/tail calls:
mov x17, sp
and x17, x17, x16
mov sp, x17
However, x17 can be live in those locations, for example when the call
is an indirect call, using x17 as the target address (blr x17).
To fix this, this patch looks for an available register just before the
call or terminator instruction and uses that.
In the rare case when no register turns out to be available (this
situation is only encountered twice across the whole test-suite), just
insert a full speculation barrier at the start of the basic block where
this occurs.
Differential Revision: https://reviews.llvm.org/D56717
llvm-svn: 351930
Two backend optimizations failed to handle cases when compiled with -g, due
to failing to consider DBG_VALUE instructions. This was in
SystemZTargetLowering::emitSelect() and
SystemZElimCompare::getRegReferences().
This patch makes sure that DBG_VALUEs are recognized so that they do not
affect these optimizations.
Tests for branch-on-count, load-and-trap and consecutive selects.
Review: Ulrich Weigand
https://reviews.llvm.org/D57048
llvm-svn: 351928
Each hwasan check requires emitting a small piece of code like this:
https://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html#memory-accesses
The problem with this is that these code blocks typically bloat code
size significantly.
An obvious solution is to outline these blocks of code. In fact, this
has already been implemented under the -hwasan-instrument-with-calls
flag. However, as currently implemented this has a number of problems:
- The functions use the same calling convention as regular C functions.
This means that the backend must spill all temporary registers as
required by the platform's C calling convention, even though the
check only needs two registers on the hot path.
- The functions take the address to be checked in a fixed register,
which increases register pressure.
Both of these factors can diminish the code size effect and increase
the performance hit of -hwasan-instrument-with-calls.
The solution that this patch implements is to involve the aarch64
backend in outlining the checks. An intrinsic and pseudo-instruction
are created to represent a hwasan check. The pseudo-instruction
is register allocated like any other instruction, and we allow the
register allocator to select almost any register for the address to
check. A particular combination of (register selection, type of check)
triggers the creation in the backend of a function to handle the check
for specifically that pair. The resulting functions are deduplicated by
the linker. The pseudo-instruction (really the function) is specified
to preserve all registers except for the registers that the AAPCS
specifies may be clobbered by a call.
To measure the code size and performance effect of this change, I
took a number of measurements using Chromium for Android on aarch64,
comparing a browser with inlined checks (the baseline) against a
browser with outlined checks.
Code size: Size of .text decreases from 243897420 to 171619972 bytes,
or a 30% decrease.
Performance: Using Chromium's blink_perf.layout microbenchmarks I
measured a median performance regression of 6.24%.
The fact that a perf/size tradeoff is evident here suggests that
we might want to make the new behaviour conditional on -Os/-Oz.
But for now I've enabled it unconditionally, my reasoning being that
hwasan users typically expect a relatively large perf hit, and ~6%
isn't really adding much. We may want to revisit this decision in
the future, though.
I also tried experimenting with varying the number of registers
selectable by the hwasan check pseudo-instruction (which would result
in fewer variants being created), on the hypothesis that creating
fewer variants of the function would expose another perf/size tradeoff
by reducing icache pressure from the check functions at the cost of
register pressure. Although I did observe a code size increase with
fewer registers, I did not observe a strong correlation between the
number of registers and the performance of the resulting browser on the
microbenchmarks, so I conclude that we might as well use ~all registers
to get the maximum code size improvement. My results are below:
Regs | .text size | Perf hit
-----+------------+---------
~all | 171619972 | 6.24%
16 | 171765192 | 7.03%
8 | 172917788 | 5.82%
4 | 177054016 | 6.89%
Differential Revision: https://reviews.llvm.org/D56954
llvm-svn: 351920
It might be a bit nicer to use the fancy .legalIf and co. predicates,
but this was requiring more boilerplate and disables the coverage
assertions.
llvm-svn: 351886
For AMDGPU the shift amount is never 64-bit, and
this needs to use a 32-bit shift.
X86 uses i8, but seemed to be hacking around this before.
llvm-svn: 351882
Summary: Enable full support for the debug info.
Reviewers: echristo
Subscribers: jholewinski, aprantl, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D46189
llvm-svn: 351846
Summary: Initial function labels must follow the debug location for the correct relocation info generation.
Reviewers: tra, jlebar, echristo
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D45784
llvm-svn: 351843
Previously we had names like 'Call' or 'Tail'. This potentially clashes with
the naming scheme used elsewhere in RISCVInstrInfo.td. Many other backends
would use names like AArch64call or PPCtail. I prefer the SystemZ approach,
which uses prefixed all-lowercase names. This matches the naming scheme used
for target-independent SelectionDAG nodes.
llvm-svn: 351823
For constant bit select patterns, replace one AND with a ANDNP, allowing us to reuse the constant mask. Only do this if the mask has multiple uses (to avoid losing load folding) or if we have XOP as its VPCMOV can handle most folding commutations.
This also requires computeKnownBitsForTargetNode support for X86ISD::ANDNP and X86ISD::FOR to prevent regressions in fabs/fcopysign patterns.
Differential Revision: https://reviews.llvm.org/D55935
llvm-svn: 351819
Similar to horizontal ops on D56777, the sse2 (but not mmx) bit shift ops has local forwarding disabled, adding +1cy to the use latency for the result.
Differential Revision: https://reviews.llvm.org/D57026
llvm-svn: 351817
Similar to horizontal ops on D56777, the vpermilpd/vpermilps variable mask ops has local forwarding disabled, adding +1cy to the use latency for the result.
Differential Revision: https://reviews.llvm.org/D57022
llvm-svn: 351815
First step towards PR40376, this patch adds support for getCmpSelInstrCost to use the (optional) Instruction CmpInst predicate to indicate the type of integer comparison we're performing and alter the costs accordingly.
Differential Revision: https://reviews.llvm.org/D57013
llvm-svn: 351810
When we are inserting 1 "inline" element, and zeroing 2 of the other elements then we can safely commute the insertps source inputs to improve memory folding.
Differential Revision: https://reviews.llvm.org/D56843
llvm-svn: 351807
Avoid the infinite loop caused by the target DAG combine converting ANYEXT to
SIGNEXT and the target-independent DAG combine logic converting back to
ANYEXT. Do this by not adding the new node to the worklist.
Committing directly as this definitely doesn't make the problem any worse, and
I intend to follow-up with a patch that avoids this custom combiner logic
altogether and just lowers the i32 operations to a target-specific
SelectionDAG node. This should be easier to reason about and improve codegen
quality in some cases (though may miss out on some later DAG combines).
llvm-svn: 351806
This broke the RISCV build, and even with that fixed, one of the RISCV
tests behaves surprisingly differently with asserts than without,
leaving there no clear test pattern to use. Generally it seems bad for
hte IR to differ substantially due to asserts (as in, an alloca is used
with asserts that isn't needed without!) and nothing I did simply would
fix it so I'm reverting back to green.
This also required reverting the RISCV build fix in r351782.
llvm-svn: 351796
The break isn't strictly needed yet as there is no subsequent entry in the
case. But adding to prevent mistakes further down the road.
llvm-svn: 351785
This patch may seem familiar... but my previous patch handled the
equivalent lsls+and, not this case. Usually instcombine puts the
"and" after the shift, so this case doesn't come up. However, if the
shift comes out of a GEP, it won't get canonicalized by instcombine,
and DAGCombine doesn't have an equivalent transform.
This also modifies isDesirableToCommuteWithShift to suppress DAGCombine
transforms which would make the overall code worse.
I'm not really happy adding a bunch of code to handle this, but it would
probably be tricky to substantially improve the behavior of DAGCombine
here.
Differential Revision: https://reviews.llvm.org/D56032
llvm-svn: 351776
Not sure this is the best fix, but it saves an instruction for certain
constructs involving variable shifts.
Differential Revision: https://reviews.llvm.org/D55572
llvm-svn: 351768
Summary:
Use X86ISD::VFPROUND in the instruction isel patterns. Add new patterns for ISD::FP_ROUND to maintain support for fptrunc in IR.
In the process I found a couple duplicate isel patterns which I also deleted in this patch.
Reviewers: RKSimon, spatel
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D56991
llvm-svn: 351762
Summary:
For compress, a select node doesn't semantically reflect the behavior of the instruction. The mask would have holes in it, but the resulting write is to contiguous elements at the bottom of the vector.
Furthermore, as far as the compressing and expanding is concerned the behavior is depended on the mask. You can't just have an expand/compress node that only reads the input vector. That node would have no meaning by itself.
This all only works because we pattern match the compress/expand+select back to the instruction. But conceivably an optimization of the select could break the pattern and leave something meaningless.
This patch modifies the expand and compress node to take the mask and passthru as additional inputs and gets rid of the select all together.
Reviewers: RKSimon, spatel
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D57002
llvm-svn: 351761
Fixes two problems with GCNHazardRecognizer:
1. It only scans up to 5 instructions emitted earlier.
2. It does not take control flow into account. An earlier instruction
from the previous basic block is not necessarily a predecessor.
At the same time a real predecessor block is not scanned.
The patch provides a way to distinguish between scheduler and
hazard recognizer mode. It is OK to work with emitted instructions
in the scheduler because we do not really know what will be emitted
later and its order. However, when pass works as a hazard recognizer
the schedule is already finalized, and we have full access to the
instructions for the whole function, so we can properly traverse
predecessors and their instructions.
Differential Revision: https://reviews.llvm.org/D56923
llvm-svn: 351759
D56777 added +1cy local forwarding penalty for horizontal operations, but this penalty only affects sse2/xmm variants, the mmx variants don't suffer the penalty.
Confirmed with @andreadb
llvm-svn: 351755
r327630 introduced new write definitions for float/vector loads.
Before that revision, WriteLoad was used by both integer/float (scalar/vector)
load. So, WriteLoad had to conservatively declare a latency to 5cy. That is
because the load-to-use latency for float/vector load is 5cy.
Now that we have dedicated writes for float/vector loads, there is no reason why
we should keep the latency of WriteLoad to 5cy. At the moment, WriteLoad is only
used by scalar integer loads only; we can assume an optimstic 3cy latency for
them.
This patch changes that latency from 5cy to 3cy, and regenerates the affected
scheduling/mca tests.
Differential Revision: https://reviews.llvm.org/D56922
llvm-svn: 351742
This updates the AVR Select8/Select16 expansion code so that, when
inserting the two basic blocks for true and false conditions, any
existing fallthrough on the previous block is preserved.
Prior to this patch, if the block before the Select pseudo fell through
to the subsequent block, two new basic blocks would be inserted at the
prior fallthrough point, changing the fallthrough destination.
The predecessor or successor lists were not updated, causing the
BranchFolding pass at -O1 and above the rearrange basic blocks, causing
an infinite loop. Not to mention the unconditional fallthrough to the
true block is incorrect in of itself.
This patch modifies the Select8/16 expansion so that, if inserting true
and false basic blocks at a fallthrough point, the implicit branch is
preserved by means of an explicit, unconditional branch to the previous
fallthrough destination.
Thanks to Carl Peto for reporting this bug.
This fixes avr-rust bug https://github.com/avr-rust/rust/issues/123.
llvm-svn: 351721
Prior to this, the code was missing AVR-specific relocation logic in
RelocVisitor.h.
This patch teaches RelocVisitor about R_AVR_16 and R_AVR_32.
Debug information is emitted in the final object file, and understood by
'avr-readelf --debug-dump' from AVR-GCC.
llvm-dwarfdump is yet to understand how to dump AVR DWARF symbols.
llvm-svn: 351720
This reverts commit r351718.
Carl pointed out that the unit test could be improved.
This patch will be recommitted once the test is made more resilient.
llvm-svn: 351719
Neil Henning