The ARM ARM is clear that 128-bit loads are only guaranteed to have been atomic
if there has been a corresponding successful stxp. It's less clear for AArch32, so
I'm leaving that alone for now.
llvm-svn: 254524
(This is the second attempt to submit this patch. The first caused two assertion
failures and was reverted. See https://llvm.org/bugs/show_bug.cgi?id=25687)
The patch in http://reviews.llvm.org/D13745 is broken into four parts:
1. New interfaces without functional changes (http://reviews.llvm.org/D13908).
2. Use new interfaces in SelectionDAG, while in other passes treat probabilities
as weights (http://reviews.llvm.org/D14361).
3. Use new interfaces in all other passes.
4. Remove old interfaces.
This patch is 3+4 above. In this patch, MBB won't provide weight-based
interfaces any more, which are totally replaced by probability-based ones.
The interface addSuccessor() is redesigned so that the default probability is
unknown. We allow unknown probabilities but don't allow using it together
with known probabilities in successor list. That is to say, we either have a
list of successors with all known probabilities, or all unknown
probabilities. In the latter case, we assume each successor has 1/N
probability where N is the number of successors. An assertion checks if the
user is attempting to add a successor with the disallowed mixed use as stated
above. This can help us catch many misuses.
All uses of weight-based interfaces are now updated to use probability-based
ones.
Differential revision: http://reviews.llvm.org/D14973
llvm-svn: 254377
and the follow-up r254356: "Fix a bug in MachineBlockPlacement that may cause assertion failure during BranchProbability construction."
Asserts were firing in Chromium builds. See PR25687.
llvm-svn: 254366
The patch in http://reviews.llvm.org/D13745 is broken into four parts:
1. New interfaces without functional changes (http://reviews.llvm.org/D13908).
2. Use new interfaces in SelectionDAG, while in other passes treat probabilities
as weights (http://reviews.llvm.org/D14361).
3. Use new interfaces in all other passes.
4. Remove old interfaces.
This patch is 3+4 above. In this patch, MBB won't provide weight-based
interfaces any more, which are totally replaced by probability-based ones.
The interface addSuccessor() is redesigned so that the default probability is
unknown. We allow unknown probabilities but don't allow using it together
with known probabilities in successor list. That is to say, we either have a
list of successors with all known probabilities, or all unknown
probabilities. In the latter case, we assume each successor has 1/N
probability where N is the number of successors. An assertion checks if the
user is attempting to add a successor with the disallowed mixed use as stated
above. This can help us catch many misuses.
All uses of weight-based interfaces are now updated to use probability-based
ones.
Differential revision: http://reviews.llvm.org/D14973
llvm-svn: 254348
Summary:
Since this build attribute corresponds to a whole module, and
different functions in a module may differ in the optimizations
enabled for them, this attribute is emitted after all functions,
and only in the case that the optimization goals for all
functions match.
Reviewers: logan, hans
Subscribers: aemerson, rengolin, llvm-commits
Differential Revision: http://reviews.llvm.org/D14934
llvm-svn: 254201
Building on r253865 the crash is not limited to signed overflows.
Disable custom handling of unsigned 32-bit and 64-bit integer divide.
Add test cases for both 32-bit and 64-bit unsigned integer overflow.
llvm-svn: 254158
The patch in http://reviews.llvm.org/D13745 is broken into four parts:
1. New interfaces without functional changes.
2. Use new interfaces in SelectionDAG, while in other passes treat probabilities
as weights.
3. Use new interfaces in all other passes.
4. Remove old interfaces.
This the second patch above. In this patch SelectionDAG starts to use
probability-based interfaces in MBB to add successors but other MC passes are
still using weight-based interfaces. Therefore, we need to maintain correct
weight list in MBB even when probability-based interfaces are used. This is
done by updating weight list in probability-based interfaces by treating the
numerator of probabilities as weights. This change affects many test cases
that check successor weight values. I will update those test cases once this
patch looks good to you.
Differential revision: http://reviews.llvm.org/D14361
llvm-svn: 253965
Disable custom handling of signed 32-bit and 64-bit integer divide.
Add test cases for both 32-bit and 64-bit integer overflow crashes.
llvm-svn: 253865
Note, this was reviewed (and more details are in) http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
These intrinsics currently have an explicit alignment argument which is
required to be a constant integer. It represents the alignment of the
source and dest, and so must be the minimum of those.
This change allows source and dest to each have their own alignments
by using the alignment attribute on their arguments. The alignment
argument itself is removed.
There are a few places in the code for which the code needs to be
checked by an expert as to whether using only src/dest alignment is
safe. For those places, they currently take the minimum of src/dest
alignments which matches the current behaviour.
For example, code which used to read:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 8, i1 false)
will now read:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 8 %dest, i8* align 8 %src, i32 500, i1 false)
For out of tree owners, I was able to strip alignment from calls using sed by replacing:
(call.*llvm\.memset.*)i32\ [0-9]*\,\ i1 false\)
with:
$1i1 false)
and similarly for memmove and memcpy.
I then added back in alignment to test cases which needed it.
A similar commit will be made to clang which actually has many differences in alignment as now
IRBuilder can generate different source/dest alignments on calls.
In IRBuilder itself, a new argument was added. Instead of calling:
CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, /* isVolatile */ false)
you now call
CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, SrcAlign, /* isVolatile */ false)
There is a temporary class (IntegerAlignment) which takes the source alignment and rejects
implicit conversion from bool. This is to prevent isVolatile here from passing its default
parameter to the source alignment.
Note, changes in future can now be made to codegen. I didn't change anything here, but this
change should enable better memcpy code sequences.
Reviewed by Hal Finkel.
llvm-svn: 253511
It turns out we decide whether to use SjLj exceptions or some alternative in
two separate places in the backend, and they disagreed with each other. This
led to inconsistent code and is generally a terrible idea.
So make them consistent and add an assert that they *do* match (unfortunately
MCAsmInfo isn't available in opt, so it can't be used to initialise the CodeGen
version directly).
llvm-svn: 253502
If a section is rw, it is irrelevant if the dynamic linker will write to
it or not.
It looks like llvm implemented this because gcc was doing it. It looks
like gcc implemented this in the hope that it would put all the
relocated items close together and speed up the dynamic linker.
There are two problem with this:
* It doesn't work. Both bfd and gold will map .data.rel to .data and
concatenate the input sections in the order they are seen.
* If we want a feature like that, it can be implemented directly in the
linker since it knowns where the dynamic relocations are.
llvm-svn: 253436
Most linked executables do not have a symbol table in COFF.
However, it is pretty typical to have some export entries. Use those
entries to inform the disassembler about potential function definitions
and call targets.
llvm-svn: 253429
The underlying issues surrounding codegen for 32-bit vselects have been resolved. The pessimistic costs for 64-bit vselects remain due to the bad
scalarization that is still happening there.
I tested this on A57 in T32, A32 and A64 modes. I saw no regressions, and some improvements.
From my benchmarks, I saw these improvements in A57 (T32)
spec.cpu2000.ref.177_mesa 5.95%
lnt.SingleSource/Benchmarks/Shootout/strcat 12.93%
lnt.MultiSource/Benchmarks/MiBench/telecomm-CRC32/telecomm-CRC32 11.89%
I also measured A57 A32, A53 T32 and A9 T32 and found no performance regressions. I see much bigger wins in third-party benchmarks with this change
Differential Revision: http://reviews.llvm.org/D14743
llvm-svn: 253349
Several places in AsmPrinter.cpp print comments describing MachineOperand
registers using MCRegisterInfo, which uses MCOperand-oriented names. This
doesn't work for targets that use virtual registers exclusively, as
WebAssembly does, since virtual registers are represented and printed
differently.
This patch preserves what seems to be the spirit of r229978, avoiding the
use of TM.getSubtargetImpl(), while still using MachineOperand-oriented
printing for MachineOperands.
Differential Revision: http://reviews.llvm.org/D14709
llvm-svn: 253338
The way prelink used to work was
* The compiler decides if a given section only has relocations that
are know to point to the same DSO. If so, it names it
.data.rel.ro.local<something>.
* The static linker puts all of these together.
* The prelinker program assigns addresses to each library and resolves
the local relocations.
There are many problems with this:
* It is incompatible with address space randomization.
* The information passed by the compiler is redundant. The linker
knows if a given relocation is in the same DSO or not. If could sort
by that if so desired.
* There are newer ways of speeding up DSO (gnu hash for example).
* Even if we want to implement this again in the compiler, the previous
implementation is pretty broken. It talks about relocations that are
"resolved by the static linker". If they are resolved, there are none
left for the prelinker. What one needs to track is if an expression
will require only dynamic relocations that point to the same DSO.
At this point it looks like the prelinker is an historical curiosity.
For example, fedora has retired it because it failed to build for two
releases
(http://pkgs.fedoraproject.org/cgit/prelink.git/commit/?id=eb43100a8331d91c801ee3dcdb0a0bb9babfdc1f)
This patch removes support for it. That is, it stops printing the
".local" sections.
llvm-svn: 253280
This was left implicit and never ever checked, which means we could have a CMPZ against some non-zero value and we were carrying on with BFI conversion regardless.
Caught by Oliver Stannard using csmith; regression test added.
llvm-svn: 253195
I completely misunderstood what ARMISD::CMPZ means. It's not "compare equal to zero", it's "compare, only setting the zero/Z flag". It can either be equal-to-zero or not-equal-to-zero, and we weren't checking what sense it was.
If it's equal-to-zero, we can swap the operands around and pretend like it is not-equal-to-zero, which is both a bug fix and lets us handle more cases.
llvm-svn: 252891
If we have a chain of BFIs, we may be able to combine several together into one merged BFI. We can do this if the "from" bits from one BFI OR'd with the "from" bits from the other BFI form a contiguous range, and the same with the "to" bits.
llvm-svn: 252740
Added fixes for stage2 failures: CMOV is not commutable; commuting the operands results in the condition being flipped! d'oh!
Original commit message:
If we have a CMOV, OR and AND combination such as:
if (x & CN)
y |= CM;
And:
* CN is a single bit;
* All bits covered by CM are known zero in y;
Then we can convert this to a sequence of BFI instructions. This will always be a win if CM is a single bit, will always be no worse than the TST & OR sequence if CM is two bits, and for thumb will be no worse if CM is three bits (due to the extra IT instruction).
llvm-svn: 252606
"GCC requires the freestanding environment provide memcpy, memmove, memset
and memcmp": https://gcc.gnu.org/onlinedocs/gcc-5.2.0/gcc/Standards.html
Hence in GNUEABI targets LLVM should not convert 'memops' to their equivalent
'__aeabi_memops'. This convertion violates GCC contract.
The -meabi flag controls whether or not LLVM will modify 'memops' in GNUEABI
targets.
Without -meabi: use the triple default EABI.
With -meabi=default: use the triple default EABI.
With -meabi=gnu: use 'memops'.
With -meabi=4 or -meabi=5: use '__aeabi_memops'.
With -meabi set to an unknown value: same as -meabi=default.
Patch by Vinicius Tinti.
llvm-svn: 252462
We don't currently have any runtime library functions for operations on
f16 values (other than conversions to and from f32 and f64), so we
should always promote it to f32, even if that is not a legal type. In
that case, the f32 values would be softened to f32 library calls.
SoftenFloatRes_FP_EXTEND now needs to check the promoted operand's type,
as it may ne a no-op or require a different library call.
getCopyFromParts and getCopyToParts now need to cope with a
floating-point value stored in a larger integer part, as is the case for
any target that needs to store an f16 value in a 32-bit integer
register.
Differential Revision: http://reviews.llvm.org/D12856
llvm-svn: 252459
Previously, subprograms contained a metadata reference to the function they
described. Because most clients need to get or set a subprogram for a given
function rather than the other way around, this created unneeded inefficiency.
For example, many passes needed to call the function llvm::makeSubprogramMap()
to build a mapping from functions to subprograms, and the IR linker needed to
fix up function references in a way that caused quadratic complexity in the IR
linking phase of LTO.
This change reverses the direction of the edge by storing the subprogram as
function-level metadata and removing DISubprogram's function field.
Since this is an IR change, a bitcode upgrade has been provided.
Fixes PR23367. An upgrade script for textual IR for out-of-tree clients is
attached to the PR.
Differential Revision: http://reviews.llvm.org/D14265
llvm-svn: 252219
If we have a CMOV, OR and AND combination such as:
if (x & CN)
y |= CM;
And:
* CN is a single bit;
* All bits covered by CM are known zero in y;
Then we can convert this to a sequence of BFI instructions. This will always be a win if CM is a single bit, will always be no worse than the TST & OR sequence if CM is two bits, and for thumb will be no worse if CM is three bits (due to the extra IT instruction).
llvm-svn: 252057
At the LLVM level this ABI is essentially a minimal modification of AAPCS to
support 16-byte alignment for vector types and the stack.
llvm-svn: 251570
Summary: After D13851 landed, we saw backend crashes when compiling the reduced test case included in this patch. The right fix seems to be to allow these vector types for expansion in instruction selection.
Reviewers: rengolin, t.p.northover
Subscribers: RKSimon, t.p.northover, aemerson, llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D14082
llvm-svn: 251401
Both VLDRS and VLDRD fault if the memory is not 4 byte aligned, which wasn't
really being checked before, leading to faults at runtime.
llvm-svn: 251352
In PIC mode we were previously computing global variable addresses (or GOT
entry addresses) by adding the PC, the PC-relative GOT displacement and
the GOT-relative symbol/GOT entry displacement. Because the latter two
displacements are fixed, we ended up performing one more addition than
necessary.
This change causes us to compute addresses using a single PC-relative
displacement, resulting in a shorter code sequence. This reduces code size
by about 4% in a recent build of Chromium for Android.
As a result of this change we no longer need to compute the GOT base address
in the ARM backend, which allows us to remove the Global Base Reg pass and
SDAG lowering for the GOT.
We also now no longer use the GOT when addressing a symbol which is known
to be defined in the same linkage unit. Specifically, the symbol must have
either hidden visibility or a strong definition in the current module in
order to not use the the GOT.
This is a change from the previous behaviour where we would use the GOT to
address externally visible symbols defined in the same module. I think the
only cases where this could matter are cases involving symbol interposition,
but we don't really support that well anyway.
Differential Revision: http://reviews.llvm.org/D13650
llvm-svn: 251322
Summary:
When ARMFrameLowering::emitPopInst generates a "pop" instruction to restore the callee saved registers, it checks if the LR register is among them. If so, the function may decide to remove the basic block's terminator and replace it with a "pop" to the PC register instead of LR.
This leads to a problem when the block's terminator is preceded by a "llvm.debugtrap" call. The MI iterator points to the trap in such a case, which is also a terminator. If the function decides to restore LR to PC, it erroneously removes the trap.
Reviewers: asl, rengolin
Subscribers: aemerson, jfb, rengolin, dschuff, llvm-commits
Differential Revision: http://reviews.llvm.org/D13672
llvm-svn: 251123
Summary:
Hyphens were missing from the triple, causing it to be parsed
incorrectly. This patch updates the triple and makes necessary
changes to the expected output.
Patch is from Vinicius Tinti.
Reviewers: ab, tinti
Subscribers: srhines, llvm-commits
Differential Revision: http://reviews.llvm.org/D13792
llvm-svn: 251020
These were the cause of a verifier error when building 7zip with
-verify-machineinstrs. Running 'make check' with the verifier
triggered the same error on the test here so i've updated the test
to run the verifier on one of its runs instead of adding a new one.
While looking at this code, there was a stale comment that these
instructions were only used for disassembly. This probably used to
be the case, but they are now used in the 'ARM load / store optimization pass' too.
This reapplies r242300 which was reverted in r242428 due to bot failures.
Ultimately those failures were spurious and completely unrelated to this commit. I reverted this
at the time because it was thought to be at fault.
llvm-svn: 250969
Summary:
TargetLoweringBase::Expand is defined as "Try to expand this to other ops,
otherwise use a libcall." For ISD::UDIV and ISD::SDIV, the choice between
the two possibilities was defined in a rather convoluted way:
- if DIVREM is legal, expand to DIVREM
- if DIVREM has a custom lowering, expand to DIVREM
- if DIVREM libcall is defined and a remainder from the same division is
computed elsewhere, expand to a DIVREM libcall
- else, expand to a DIV libcall
This had the undesirable effect that if both DIV and DIVREM are implemented
as libcalls, then ISD::UDIV and ISD::SDIV are expanded to the heavier DIVREM
libcall, even when the remainder isn't used.
The new code adds a new LegalizeAction, TargetLoweringBase::LibCall, so that
backends can directly control whether they prefer an expansion or a conversion
to a libcall. This makes the generic lowering code even more generic,
allowing its reuse in a wider range of target-specific configurations.
The useful effect is that ARM backend will now generate a call
to __aeabi_{i,u}div rather than __aeabi_{i,u}divmod in cases where
it doesn't need the remainder. There's no functional change outside
the ARM backend.
Reviewers: t.p.northover, rengolin
Subscribers: t.p.northover, llvm-commits, aemerson
Differential Revision: http://reviews.llvm.org/D13862
llvm-svn: 250826
The mapping of these two intrinsics in ARMInstrInfo.td had a small
omission which lead to their operands not being validated/transformed
before being lowered into usat and ssat instructions. This can cause
incorrect instructions to be emitted.
I've also added tests for the remaining two saturating arithmatic
intrinsics @llvm.arm.qadd and @llvm.arm.qsub as they are missing
codegen tests.
llvm-svn: 250697
Accept r11 when targeting Windows on ARM rather than just low registers.
Because we are in a thumb-2 only mode, this may be slightly more expensive in
code size, but results in better code for the environment since it spills the
frame register, which is generally desired for fast stack walking as per the
ABI.
llvm-svn: 249804
I'll be using the function in a similar combine for AArch64. The helper was
also improved to handle undef values.
Part of http://reviews.llvm.org/D13442
llvm-svn: 249572
Tim Northover