There's no neg.f16 instruction, so negation has to
be done via subtraction from zero.
Differential Revision: https://reviews.llvm.org/D28876
llvm-svn: 292452
r291670 doesn't crash on the original testcase from PR31589,
but it crashes on a slightly more complex one.
PR31589 has the new reproducer.
llvm-svn: 292444
ARM seems to prefer that long literals be formed from their little end in
order to promote the fusion of the instrs pairs MOV/MOVK and MOVK/MOVK on
Cortex A57 and others (v. "Cortex A57 Software Optimisation Guide", section
4.14).
Differential revision: https://reviews.llvm.org/D28697
llvm-svn: 292422
Limit register coalescer by not allowing it to artificially increase
size of registers beyond dword. Such super-registers are in fact
register sequences and not distinct HW registers.
With more super-regs we would need to allocate adjacent registers
and constraint regalloc more than needed. Moreover, our super
registers are overlapping. For instance we have VGPR0_VGPR1_VGPR2,
VGPR1_VGPR2_VGPR3, VGPR2_VGPR3_VGPR4 etc, which complicates registers
allocation even more, resulting in excessive spilling.
Differential Revision: https://reviews.llvm.org/D28782
llvm-svn: 292413
Non-prevailing weak/linkonce odr symbols will be dropped by ThinLTO to
available_externally when possible. If they had an initializer in the
global_ctors list, a comdat group was being created. This code
already had logic to skip available_externally defs, but now the
EliminateAvailableExternally pass will drop these symbols to
declarations earlier. Change the check to skip all declarations for
linker (which includes available_externally along with declarations).
Reviewers: mehdi_amini
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D28737
llvm-svn: 292408
This patch improves the mul instruction combine function (combineMul)
by adding new layer of logic.
In this patch, we are adding the ability to fold (mul x, -((1 << c) -1))
or (mul x, -((1 << c) +1)) into (neg(X << c) -x) or (neg((x << c) + x) respective.
Differential Revision: https://reviews.llvm.org/D28232
llvm-svn: 292358
This reverts commit r292210, as it broke the Thumb buldbot with:
clang-5.0: error: the clang compiler does not support '-fxray-instrument
on thumbv7-unknown-linux-gnueabihf'.
llvm-svn: 292357
During post-RA pseudo expansion, an 'undef' flag of the source operand should
be propagated by emitGRX32Move().
Review: Ulrich Weigand
llvm-svn: 292353
You can now define the register class of a virtual register on the
operand itself avoiding the need to use a "registers:" block.
Example: "%0:gr64 = COPY %rax"
Differential Revision: https://reviews.llvm.org/D22398
llvm-svn: 292321
Summary:
This change also lets us use max.{s,u}16. There's a vague warning in a
test about this maybe being less efficient, but I could not come up with
a case where the resulting SASS (sm_35 or sm_60) was different with or
without max.{s,u}16. It's true that nvcc seems to emit only
max.{s,u}32, but even ptxas 7.0 seems to have no problem generating
efficient SASS from max.{s,u}16 (the casts up to i32 and back down to
i16 seem to be implicit and nops, happening via register aliasing).
In the absence of evidence, better to have fewer special cases, emit
more straightforward code, etc. In particular, if a new GPU has 16-bit
min/max instructions, we want to be able to use them.
Reviewers: tra
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D28732
llvm-svn: 292304
Summary: Previously we lowered it literally, to shifts and xors.
Reviewers: tra
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D28722
llvm-svn: 292303
Summary:
Avoid an unnecessary conversion operation when using the result of
ctpop.i32 or ctpop.i16 as an i32, as in both cases the ptx instruction
we run returns an i32.
(Previously if we used the value as an i32, we'd do an unnecessary
zext+trunc.)
Reviewers: tra
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D28721
llvm-svn: 292302
Summary:
* Disable "ctlz speculation", which inserts a branch on every ctlz(x) which
has defined behavior on x == 0 to check whether x is, in fact zero.
* Add DAG patterns that avoid re-truncating or re-expanding the result
of the 16- and 64-bit ctz instructions.
Reviewers: tra
Subscribers: llvm-commits, jholewinski
Differential Revision: https://reviews.llvm.org/D28719
llvm-svn: 292299
The patch is to solve the performance problem described in PR27827.
Register coalescing sometimes cannot remove a copy because of interference.
But if we can find a reverse copy in one of the predecessor block of the copy,
the copy is partially redundent and we may remove the copy partially by moving
it to the predecessor block without the reverse copy.
Differential Revision: https://reviews.llvm.org/D28585
llvm-svn: 292292
Some platforms (notably iOS) use a different calling convention for unnamed vs
named parameters in varargs functions, so we need to keep track of this
information when translating calls.
Since not many platforms are involved, the guts of the special handling is in
the ValueHandler class (with a generic implementation that should work for most
targets).
llvm-svn: 292283
Correctly populating Machine PHIs relies on knowing exactly how the IR level
CFG was lowered to MachineIR. This needs to be tracked by any translation
phases that meddle (currently only SwitchInst handling).
This reapplies r291973 which was reverted because of testing failures. Fixes:
+ Don't return an ArrayRef to a local temporary.
+ Incorporate Kristof's suggested comment improvements.
llvm-svn: 292278
Even with the fix from r291630, this still causes problems. I get
widespread assertion failures in the Swift runtime's WeakRefCount::increment()
function. I sent a reduced testcase in reply to the commit.
llvm-svn: 292242
Summary:
Emission of XRay table was occasionally disabled for Arm32, but this bug was not then detected because earlier (also by mistake) testing of XRay was occasionally disabled on 32-bit Arm targets. This patch should fix that problem and detect such problems in the future.
This patch is one of a series, see also
- https://reviews.llvm.org/D28623
Reviewers: rengolin, dberris
Reviewed By: dberris
Subscribers: llvm-commits, aemerson, rengolin, dberris, iid_iunknown
Differential Revision: https://reviews.llvm.org/D28624
llvm-svn: 292210
Emit error when BPF backend sees a call to a global function or to an external symbol.
The kernel verifier only allows calls to predefined helpers from bpf.h
which are defined in 'enum bpf_func_id'. Such calls in assembler must
look like 'call [1-9]+' where number matches bpf_func_id.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 292204
SelectionDAGBuilder recognizes libfuncs using some homegrown
parameter type-checking.
Use TLI instead, removing another heap of redundant code.
This isn't strictly NFC, as the SDAG code was too lax.
Concretely, this means changes are required to two tests:
- calling a non-variadic function via a variadic prototype isn't OK;
it just happens to work on x86_64 (but not on, e.g., aarch64).
- mempcpy has a size_t parameter; the SDAG code accepts any integer
type, which meant using i32 on x86_64 worked.
I don't think it's worth supporting either of these (IMO) broken
testcases. Instead, fix them to be more correct.
llvm-svn: 292189
Generally, the ISEL is expanded into if-then-else sequence, in some
cases (like when the destination register is the same with the true
or false value register), it may just be expanded into just the if
or else sequence.
llvm-svn: 292154
Falkor only partially implements the ARMv8.1a extensions, so this patch
refactors the support for the SQRDML[A|S]H instruction into a separate
feature.
Differential Revision: https://reviews.llvm.org/D28681
llvm-svn: 292142