TLS access requires an offset from the TLS index. The index itself is the
section-relative distance of the symbol. For ARM, the relevant relocation
(IMAGE_REL_ARM_SECREL) is applied as a constant. This means that the value may
not be an immediate and must be lowered into a constant pool. This offset will
not be base relocated. We were previously emitting the actual address of the
symbol which would be base relocated and would therefore be the vaue offset by
the ImageBase + TLS Offset.
llvm-svn: 271974
new instruction to ARM and AArch64 targets and several system registers.
Patch by: Roger Ferrer Ibanez and Oliver Stannard
Differential Revision: http://reviews.llvm.org/D20282
llvm-svn: 271670
I'm really not sure why we were in the first place, it's the linker's job to
convert between BL/BLX as necessary. Even worse, using BLX left Thumb calls
that could be locally resolved completely unencodable since all offsets to BLX
are multiples of 4.
rdar://26182344
llvm-svn: 269101
Summary:
This patch adds support for the X asm constraint.
To do this, we lower the constraint to either a "w" or "r" constraint
depending on the operand type (both constraints are supported on ARM).
Fixes PR26493
Reviewers: t.p.northover, echristo, rengolin
Subscribers: joker.eph, jgreenhalgh, aemerson, rengolin, llvm-commits
Differential Revision: http://reviews.llvm.org/D19061
llvm-svn: 267411
This corrects the MI annotations for the stack adjustment following the __chkstk
invocation. We were marking the original SP usage as a Def rather than Kill.
The (new) assigned value is the definition, the original reference is killed.
Adjust the ISelLowering to mark Kills and FrameSetup as well.
This partially resolves PR27480.
llvm-svn: 267361
Because lowering of CMP_SWAP_64 occurs during type legalization, there can be
i64 types produced by more than just a BUILD_PAIR or similar. My initial tests
used just incoming function args.
llvm-svn: 266828
Both AArch64 and ARM support llvm.<arch>.thread.pointer intrinsics that
just return the thread pointer. I have a pending patch that does the same
for SystemZ (D19054), and there are many more targets that could benefit
from one.
This patch merges the ARM and AArch64 intrinsics into a single target
independent one that will also be used by subsequent targets.
Differential Revision: http://reviews.llvm.org/D19098
llvm-svn: 266818
The fast register-allocator cannot cope with inter-block dependencies without
spilling. This is fine for ldrex/strex loops coming from atomicrmw instructions
where any value produced within a block is dead by the end, but not for
cmpxchg. So we lower a cmpxchg at -O0 via a pseudo-inst that gets expanded
after regalloc.
Fortunately this is at -O0 so we don't have to care about performance. This
simplifies the various axes of expansion considerably: we assume a strong
seq_cst operation and ensure ordering via the always-present DMB instructions
rather than v8 acquire/release instructions.
Should fix the 32-bit part of PR25526.
llvm-svn: 266679
It is very likely that the swiftself parameter is alive throughout most
functions function so putting it into a callee save register should
avoid spills for the callers with only a minimum amount of extra spills
in the callees.
Currently the generated code is correct but unnecessarily spills and
reloads arguments passed in callee save registers, I will address this
in upcoming patches.
This also adds a missing check that for tail calls the preserved value
of the caller must be the same as the callees parameter.
Differential Revision: http://reviews.llvm.org/D18901
llvm-svn: 266253
Summary:
In the context of http://wg21.link/lwg2445 C++ uses the concept of
'stronger' ordering but doesn't define it properly. This should be fixed
in C++17 barring a small question that's still open.
The code currently plays fast and loose with the AtomicOrdering
enum. Using an enum class is one step towards tightening things. I later
also want to tighten related enums, such as clang's
AtomicOrderingKind (which should be shared with LLVM as a 'C++ ABI'
enum).
This change touches a few lines of code which can be improved later, I'd
like to keep it as NFC for now as it's already quite complex. I have
related changes for clang.
As a follow-up I'll add:
bool operator<(AtomicOrdering, AtomicOrdering) = delete;
bool operator>(AtomicOrdering, AtomicOrdering) = delete;
bool operator<=(AtomicOrdering, AtomicOrdering) = delete;
bool operator>=(AtomicOrdering, AtomicOrdering) = delete;
This is separate so that clang and LLVM changes don't need to be in sync.
Reviewers: jyknight, reames
Subscribers: jyknight, llvm-commits
Differential Revision: http://reviews.llvm.org/D18775
llvm-svn: 265602
We can only perform a tail call to a callee that preserves all the
registers that the caller needs to preserve.
This situation happens with calling conventions like preserver_mostcc or
cxx_fast_tls. It was explicitely handled for fast_tls and failing for
preserve_most. This patch generalizes the check to any calling
convention.
Related to rdar://24207743
Differential Revision: http://reviews.llvm.org/D18680
llvm-svn: 265329
ThreadModel::Single is already handled already by ARMPassConfig adding
LowerAtomicPass to the pass list, which lowers all atomics to non-atomic
ops and deletes fences.
So by the time we get to ISel, there's no atomic fences left, so they
don't need special handling.
llvm-svn: 265178
It is possible to have a fallthrough MBB prior to MBB placement. The original
addition of the BB would result in reordering the BB as not preceding the
successor. Because of the fallthrough nature of the BB, we could end up
executing incorrect code or even a constant pool island! Insert the spliced BB
into the same location to avoid that.
Thanks to Tim Northover for invaluable hints and Fiora for the discussion on
what may have been occurring!
llvm-svn: 264454
We did not have an explicit branch to the continuation BB. When the check was
hoisted, this could permit control follow to fall through into the division
trap. Add the explicit branch to the continuation basic block to ensure that
code execution is correct.
llvm-svn: 264370
This introduces a custom lowering for ISD::SETCCE (introduced in r253572)
that allows us to emit a short code sequence for 64-bit compares.
Before:
push {r7, lr}
cmp r0, r2
mov.w r0, #0
mov.w r12, #0
it hs
movhs r0, #1
cmp r1, r3
it ge
movge.w r12, #1
it eq
moveq r12, r0
cmp.w r12, #0
bne .LBB1_2
@ BB#1: @ %bb1
bl f
pop {r7, pc}
.LBB1_2: @ %bb2
bl g
pop {r7, pc}
After:
push {r7, lr}
subs r0, r0, r2
sbcs.w r0, r1, r3
bge .LBB1_2
@ BB#1: @ %bb1
bl f
pop {r7, pc}
.LBB1_2: @ %bb2
bl g
pop {r7, pc}
Saves around 80KB in Chromium's libchrome.so.
Some notes on this patch:
- I don't much like the ARMISD::BRCOND and ARMISD::CMOV combines I
introduced (nothing else needs them). However, they are necessary in
order to avoid poor codegen, and they seem similar to existing combines
in other backends (e.g. X86 combines (brcond (cmp (setcc Compare))) to
(brcond Compare)).
- No support for Thumb-1. This is in principle possible, but we'd need
to implement ARMISD::SUBE for Thumb-1.
Differential Revision: http://reviews.llvm.org/D15256
llvm-svn: 263962
The two changes together weakened the test and caused a regression with division
handling in MSVC mode. They were applied to avoid an assertion being triggered
in the block frequency analysis. However, the underlying problem was simply
being masked rather than solved properly. Address the actual underlying problem
and revert the changes. Rather than analyze the cause of the assertion, the
division failure was assumed to be an overflow.
The underlying issue was a subtle bug in the BB construction in the emission of
the div-by-zero check (WIN__DBZCHK). We did not construct the proper successor
information in the basic blocks, nor did we update the PHIs associated with the
basic block when we split them. This would result in assertions being triggered
in the block frequency analysis pass.
Although the original tests are being removed, the tests themselves performed
very little in terms of validation but merely tested that we did not assert when
generating code. Update this with new tests that actually ensure that we do not
regress on the code generation.
llvm-svn: 263714
- Rename getATOMIC to getSYNC, as llvm will soon be able to emit both
'__sync' libcalls and '__atomic' libcalls, and this function is for
the '__sync' ones.
- getInsertFencesForAtomic() has been replaced with
shouldInsertFencesForAtomic(Instruction), so that the decision can be
made per-instruction. This functionality will be used soon.
- emitLeadingFence/emitTrailingFence are no longer called if
shouldInsertFencesForAtomic returns false, and thus don't need to
check the condition themselves.
llvm-svn: 263665
This change adds a support for a preserve_most calling convention to the AArch64 backend, similar to how it was done for X86-64.
There is also a subsequent patch on top of this one to add a tail-calls support for this calling convention.
Differential Revision: http://reviews.llvm.org/D18016
llvm-svn: 263092
When div+rem calls on the same arguments are found, the ARM back-end merges the
two calls into one __aeabi_divmod call for up to 32-bits values. However,
for 64-bit values, which also have a lib call (__aeabi_ldivmod), it wasn't
merging the calls, and thus calling ldivmod twice and spilling the temporary
results, which generated pretty bad code.
This patch legalises 64-bit lib calls for divmod, so that now all the spilling
and the second call are gone. It also relaxes the DivRem combiner a bit on the
legal type check, since it was already checking for isLegalOrCustom on every
value, so the extra check for isTypeLegal was redundant.
Second attempt, creating TLI.isOperationCustom like isOperationExpand, to make
sure we only emit valid types or the ones that were explicitly marked as custom.
Now, passing check-all and test-suite on x86, ARM and AArch64.
This patch fixes PR17193 (and a long time FIXME in the tests).
llvm-svn: 262738
When div+rem calls on the same arguments are found, the ARM back-end merges the
two calls into one __aeabi_divmod call for up to 32-bits values. However,
for 64-bit values, which also have a lib call (__aeabi_ldivmod), it wasn't
merging the calls, and thus calling ldivmod twice and spilling the temporary
results, which generated pretty bad code.
This patch legalises 64-bit lib calls for divmod, so that now all the spilling
and the second call are gone. It also relaxes the DivRem combiner a bit on the
legal type check, since it was already checking for isLegalOrCustom on every
value, so the extra check for isTypeLegal was redundant.
This patch fixes PR17193 (and a long time FIXME in the tests).
llvm-svn: 262507
Summary:
If we want classify OoO or not, using getSchedModel().isOutOfOrder()
could be more proper way than using Subtarget->isLikeA9().
Reviewers: jmolloy, rengolin
Differential Revision: http://reviews.llvm.org/D17433
llvm-svn: 261623
Add support for TLS access for Windows on ARM. This generates a similar access
to MSVC for ARM.
The changes to the tablegen data is needed to support loading an external symbol
global that is not for a call. The adjustments to the DAG to DAG transforms are
needed to preserve the 32-bit move.
llvm-svn: 259676
The GNU toolchain emits __aeabi_divmod for soft-divide on ARM cores
which happens to be a lot faster than __divsi3/__modsi3 when the core
has hardware divide instructions. Do the same here.
Fixes PR26450.
llvm-svn: 259657
Various bits we want to use the new ABI actually compile with "-arch armv7k
-miphoneos-version-min=9.0". Not ideal, but also not ridiculous given how
slices work.
llvm-svn: 258975
When we have a single basic block, the explicit copy-back instructions should
be inserted right before the terminator. Before this fix, they were wrongly
placed at the beginning of the basic block.
PR26136
llvm-svn: 257930
Summary:
r255334 matches bit-reverse pattern in InstCombine and generates calls to Instrinsic::bitreverse.
RBIT instruction is only available for ARMv6t2 and above. This patch has the intrinsic expanded during legalization for ARMv4 and ARMv5.
Patch by Z. Zheng <zhaoshiz@codeaurora.org>
Reviewers: apazos, jmolloy, weimingz
Subscribers: aemerson, rengolin, llvm-commits
Differential Revision: http://reviews.llvm.org/D15932
llvm-svn: 257188
Darwin TLS accesses most closely resemble ELF's general-dynamic situation,
since they have to be able to handle all possible situations. The descriptors
and so on are obviously slightly different though.
llvm-svn: 257039
This patch adds some missing calls to MBB::normalizeSuccProbs() in several
locations where it should be called. Those places are found by checking if the
sum of successors' probabilities is approximate one in MachineBlockPlacement
pass with some instrumented code (not in this patch).
Differential revision: http://reviews.llvm.org/D15259
llvm-svn: 255455
After much discussion, ending here:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151123/315620.html
it has been decided that, instead of having the vectorizer directly generate
special absdiff and horizontal-add intrinsics, we'll recognize the relevant
reduction patterns during CodeGen. Accordingly, these intrinsics are not needed
(the operations they represent can be pattern matched, as is already done in
some backends). Thus, we're backing these out in favor of the current
development work.
r248483 - Codegen: Fix llvm.*absdiff semantic.
r242546 - [ARM] Use [SU]ABSDIFF nodes instead of intrinsics for VABD/VABA
r242545 - [AArch64] Use [SU]ABSDIFF nodes instead of intrinsics for ABD/ABA
r242409 - [Codegen] Add intrinsics 'absdiff' and corresponding SDNodes for absolute difference operation
llvm-svn: 255387
Otherwise, we think that most types that look like they'd fit in a
legal vector type are legal (so, basically, *any* vector type with a
size between 33 and 128 bits, I think, since we use pow2 alignment;
e.g., v2i25, v3f32, ...).
DataLayout::getTypeAllocSize rounds up based on alignment.
When checking for target intrinsic legality, that's not what we want:
if rounding makes a difference, the type isn't legal, and the
target intrinsics shouldn't be used, as they are always assumed legal.
One could make the argument that alloc size is ultimately the most
relevant here, since we're dealing with LD/ST intrinsics. That's only
true if we did legalize them though; that's a problem for another day.
Use DataLayout::getTypeSizeInBits instead of getTypeAllocSizeInBits.
Type::getSizeInBits can't be used because that'd gratuitously break
pointer vector support.
Some of these uses are currently fine, because we only hit them when
the type is already known legal (e.g., r114454). Update them for
consistency. It's faster to avoid the rounding anyway!
llvm-svn: 255089
with its source instead of forcing the values on GPRs.
This improves the lowering of vector code when such bitcasts happen in the
middle of vector computations.
rdar://problem/23691584
llvm-svn: 254684
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
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
Summary:
Many target lowerings copy-paste the code to test SDValues for known constants.
This code can instead be shared in SelectionDAG.cpp, and reused in the targets.
Reviewers: MatzeB, andreadb, tstellarAMD
Subscribers: arsenm, jyknight, llvm-commits
Differential Revision: http://reviews.llvm.org/D14945
llvm-svn: 254085
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
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
I missed the side-effects of ParseBFI in my previous attempt (r252748).
Thanks dblaikie for the suggestion of adding a void use of the unused
variable instead.
llvm-svn: 252751
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
ARM V6T2 has instructions for efficient count-leading/trailing-zeros, so this should be
considered a cheap operation (and therefore fair game for speculation) for any ARM V6T2
implementation.
The net result of allowing this speculation for the regression tests in this patch is
that we get this code:
ctlz:
clz r0, r0
bx lr
cttz:
rbit r0, r0
clz r0, r0
bx lr
Instead of:
ctlz:
cmp r0, #0
moveq r0, #32
clzne r0, r0
bx lr
cttz:
cmp r0, #0
moveq r0, #32
rbitne r0, r0
clzne r0, r0
bx lr
This will help solve a general speculation/despeculation problem noted in PR24818:
https://llvm.org/bugs/show_bug.cgi?id=24818
Differential Revision: http://reviews.llvm.org/D14469
llvm-svn: 252639
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
Summary:
The CLR's personality routine passes these in rdx/edx, not rax/eax.
Make getExceptionPointerRegister a virtual method parameterized by
personality function to allow making this distinction.
Similarly make getExceptionSelectorRegister a virtual method parameterized
by personality function, for symmetry.
Reviewers: pgavlin, majnemer, rnk
Subscribers: jyknight, dsanders, llvm-commits
Differential Revision: http://reviews.llvm.org/D14344
llvm-svn: 252383
We can conservatively know that CMOV's known bits are the intersection of known bits for each of its operands. This helps PerformCMOVToBFICombine find more opportunities.
I tried hard to create a testcase for this and failed - we have to sufficiently confuse DAG.computeKnownBits which can see through all the cheap tricks I tried to narrow my larger testcase down :(
This code is actually exercised in CodeGen/ARM/bfi.ll, there's just no functional difference because DAG.computeKnownBits gets the right answer in that case.
llvm-svn: 252168
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
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
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:
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
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
The ARM RTABI defines the half- to single-precision float conversion functions
with an __aeabi prefix, but libgcc only has them with a __gnu prefix. Therefore
we need to emit the __aeabi version when compiling with an eabi or eabihf
triple, and the __gnu version with a gnueabi or gnueabihf triple.
llvm-svn: 249565
Without an additional check for NEON, the compiler crashes during
legalization of NEON ldN/stN.
Differential Revision: http://reviews.llvm.org/D13508
llvm-svn: 249550
We were previously codegen'ing memcpy as regular load/store operations and
hoping that the register allocator would allocate registers in ascending order
so that we could apply an LDM/STM combine after register allocation. According
to the commit that first introduced this code (r37179), we planned to teach the
register allocator to allocate the registers in ascending order. This never got
implemented, and up to now we've been stuck with very poor codegen.
A much simpler approach for achieving better codegen is to create MEMCPY pseudo
instructions, attach scratch virtual registers to them and then, post register
allocation, expand the MEMCPYs into LDM/STM pairs using the scratch registers.
The register allocator will have picked arbitrary registers which we sort when
expanding the MEMCPY. This approach also avoids the need to repeatedly calculate
offsets which ultimately ought to be eliminated pre-RA in order to decrease
register pressure.
Fixes PR9199 and PR23768.
[This is based on Peter Collingbourne's r238473 which was reverted.]
Differential Revision: http://reviews.llvm.org/D13239
Change-Id: I727543c2e94136e0f80b8e22d5642d7b9ee5b458
Author: Peter Collingbourne <peter@pcc.me.uk>
llvm-svn: 249322
This commit changes the interface of the vld[1234], vld[234]lane, and vst[1234],
vst[234]lane ARM neon intrinsics and associates an address space with the
pointer that these intrinsics take. This changes, e.g.,
<2 x i32> @llvm.arm.neon.vld1.v2i32(i8*, i32)
to
<2 x i32> @llvm.arm.neon.vld1.v2i32.p0i8(i8*, i32)
This change ensures that address spaces are fully taken into account in the ARM
target during lowering of interleaved loads and stores.
Differential Revision: http://reviews.llvm.org/D12985
llvm-svn: 248887
supportsTailCall() has two callers. Both of them double-check isThumb1Only(),
and refuse to proceed with tail-calling in that case.
Therefore, it makes sense to move this check to
ARMSubtarget::initSubtargetFeatures, where SupportsTailCall is initialized;
and to eliminate the extra checks at the call sites.
Following a review comment, added an "assert(supportsTailCall())"
in IsEligibleForTailCall.
NFC.
llvm-svn: 248703
We now emit the compiler generated divide by zero check that was needed for the
MSVC routines. We construct a psuedo-instruction for the DBZ check as the
operation requires splitting up the BB. For the 64-bit operations, we need to
custom expand the node as we need to insert the DBZ check and then emit the
libcall to the appropriate name. Because this is target specific, it seemed
better to reproduce the expansion operation from the target-agnostic type
legalization rather than sink this there to avoid the duplication. The division
library calls now match MSVC semantically.
llvm-svn: 248561
Currently, the availability of DSP instructions (ACLE 6.4.7) is handled in a
hand-rolled tricky condition block in tools/clang/lib/Basic/Targets.cpp, with
a FIXME: attached.
This patch changes the handling of +t2dsp to be in line with other
architecture extensions.
Following a revert of r248152 and new review comments, this patch also includes
renaming FeatureDSPThumb2 -> FeatureDSP, hasThumb2DSP() -> hasDSP(), etc.
The spelling of "t2dsp" is preserved, pending a further investigation of its
possible external usage.
Differential Revision: http://reviews.llvm.org/D12937
llvm-svn: 248519
ARM counterpart to r248291:
In the comparison failure block of a cmpxchg expansion, the initial
ldrex/ldxr will not be followed by a matching strex/stxr.
On ARM/AArch64, this unnecessarily ties up the execution monitor,
which might have a negative performance impact on some uarchs.
Instead, release the monitor in the failure block.
The clrex instruction was designed for this: use it.
Also see ARMARM v8-A B2.10.2:
"Exclusive access instructions and Shareable memory locations".
Differential Revision: http://reviews.llvm.org/D13033
llvm-svn: 248294
The vext pseudo-instruction takes the number of elements that need to be
extracted, not the number of bytes. Hence, use the number of elements
directly instead of scaling them with a factor.
Reviewers: Silviu Baranga, James Molloy
(not reflected in the differential revision)
Differential Revision: http://reviews.llvm.org/D12974
llvm-svn: 248208
After D10403, we had FMF in the DAG but disabled by default. Nick reported no crashing errors after some stress testing,
so I enabled them at r243687. However, Escha soon notified us of a bug not covered by any in-tree regression tests:
if we don't propagate the flags, we may fail to CSE DAG nodes because differing FMF causes them to not match. There is
one test case in this patch to prove that point.
This patch hopes to fix or leave a 'TODO' for all of the in-tree places where we create nodes that are FMF-capable. I
did this by putting an assert in SelectionDAG.getNode() to find any FMF-capable node that was being created without FMF
( D11807 ). I then ran all regression tests and test-suite and confirmed that everything passes.
This patch exposes remaining work to get DAG FMF to be fully functional: (1) add the flags to non-binary nodes such as
FCMP, FMA and FNEG; (2) add the flags to intrinsics; (3) use the flags as conditions for transforms rather than the
current global settings.
Differential Revision: http://reviews.llvm.org/D12095
llvm-svn: 247815
We used to have this magic "hasLoadLinkedStoreConditional()" callback,
which really meant two things:
- expand cmpxchg (to ll/sc).
- expand atomic loads using ll/sc (rather than cmpxchg).
Remove it, and, instead, introduce explicit callbacks:
- bool shouldExpandAtomicCmpXchgInIR(inst)
- AtomicExpansionKind shouldExpandAtomicLoadInIR(inst)
Differential Revision: http://reviews.llvm.org/D12557
llvm-svn: 247429
The tests in isVTRNMask and isVTRN_v_undef_Mask should also check that the elements of the upper and lower half of the vectorshuffle occur in the correct order when both halves are used. Without this test the code assumes that it is correct to use vector transpose (vtrn) for the masks <1, 1, 0, 0> and <1, 3, 0, 2>, among others, but the transpose actually incorrectly generates shuffles for <0, 0, 1, 1> and <0, 2, 1, 3> in this case.
Patch by Jeroen Ketema!
llvm-svn: 247254
The code introduced in r244314 assumed that EXTRACT_VECTOR_ELT only
takes constant indices, but it does accept variables.
Bail out for those: we can't use them, as the shuffles we want to
reconstruct do require constant masks.
llvm-svn: 246594
For targets that didn't support this, this will let us respect the
langref instead of failing to select.
Note that we don't need to change the 32-bit x86/PPC lowerings (to
account for the result type/# difference) because they're both
custom and bypass type legalization.
llvm-svn: 246258
We can now run 32-bit programs with empty catch bodies. The next step
is to change PEI so that we get funclet prologues and epilogues.
llvm-svn: 246235
It won't go well. We've already marked 64-bit SETCCs as non-Custom, but it's just possible that a SETCC has a legal result type but an illegal operand type. If this happens, bail out before we create unselectable nodes.
Fixes PR24292. I tried to create a testcase but in 99% of cases we can't trigger this - not surprising that this bug has been latent since 2009.
llvm-svn: 245577
Summary:
The mid-end was generating vector smin/smax/umin/umax nodes, but
we were using vbsl to generatate the code. This adds the vmin/vmax
patterns and a test to check that we are now generating vmin/vmax
instructions.
Reviewers: rengolin, jmolloy
Subscribers: aemerson, rengolin, llvm-commits
Differential Revision: http://reviews.llvm.org/D12105
llvm-svn: 245439
This was my error. We've got f32 marked as legal because they're simulated using a v2f32 instruction, but there's no equivalent for f64.
This will get test coverage imminently when D12015 lands.
llvm-svn: 244916
This commit removes the global manager variable which is responsible for
storing and allocating pseudo source values and instead it introduces a new
manager class named 'PseudoSourceValueManager'. Machine functions now own an
instance of the pseudo source value manager class.
This commit also modifies the 'get...' methods in the 'MachinePointerInfo'
class to construct pseudo source values using the instance of the pseudo
source value manager object from the machine function.
This commit updates calls to the 'get...' methods from the 'MachinePointerInfo'
class in a lot of different files because those calls now need to pass in a
reference to a machine function to those methods.
This change will make it easier to serialize pseudo source values as it will
enable me to transform the mips specific MipsCallEntry PseudoSourceValue
subclass into two target independent subclasses.
Reviewers: Akira Hatanaka
llvm-svn: 244693
Lower Intrinsic::arm_neon_vmins/vmaxs to fminnan/fmaxnan and match that instead. This is important because SDAG will soon be able to select FMINNAN itself, so we need a unified lowering path for intrinsics and SDAG.
NFCI.
llvm-svn: 244593
Lower the intrinsic to a FMINNUM/FMAXNUM node and select that instead. This is important because soon SDAG will be able to select FMINNUM/FMAXNUM itself, so we need an integrated lowering path between SDAG and intrinsics.
NFCI.
llvm-svn: 244592
Summary:
Port the ReconstructShuffle function from AArch64 to ARM
to handle mismatched incoming types in the BUILD_VECTOR
node.
This fixes an outstanding FIXME in the ReconstructShuffle
code.
Reviewers: t.p.northover, rengolin
Subscribers: aemerson, llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D11720
llvm-svn: 244314
Create wrapper methods in the Function class for the OptimizeForSize and MinSize
attributes. We want to hide the logic of "or'ing" them together when optimizing
just for size (-Os).
Currently, we are not consistent about this and rely on a front-end to always set
OptimizeForSize (-Os) if MinSize (-Oz) is on. Thus, there are 18 FIXME changes here
that should be added as follow-on patches with regression tests.
This patch is NFC-intended: it just replaces existing direct accesses of the attributes
by the equivalent wrapper call.
Differential Revision: http://reviews.llvm.org/D11734
llvm-svn: 243994
This adds the software division routines for the Windows RTABI. These are not
expected to be used often though as most modern Windows ARM capable targets
support hardware division. In the case that the target CPU doesnt support
hardware division, this will be the fallback.
llvm-svn: 243952
For a modulo (reminder) operation,
clang -target armv7-none-linux-gnueabi generates "__modsi3"
clang -target armv7-none-eabi generates "__aeabi_idivmod"
clang -target armv7-linux-androideabi generates "__modsi3"
Android bionic libc doesn't provide a __modsi3, instead it provides a
"__aeabi_idivmod". This patch fixes the LLVM ARMISelLowering to generate
the correct call when ever there is a modulo operation.
Differential Revision: http://reviews.llvm.org/D11661
llvm-svn: 243717
Fixing MinSize attribute handling was discussed in D11363.
This is a prerequisite patch to doing that.
The handling of OptSize when lowering mem* functions was broken
on Darwin because it wants to ignore -Os for these cases, but the
existing logic also made it ignore -Oz (MinSize).
The Linux change demonstrates a widespread problem. The backend
doesn't usually recognize the MinSize attribute by itself; it
assumes that if the MinSize attribute exists, then the OptSize
attribute must also exist.
Fixing this more generally will be a follow-on patch or two.
Differential Revision: http://reviews.llvm.org/D11568
llvm-svn: 243693
The 'common' section TLS is not implemented.
Current C/C++ TLS variables are not placed in common section.
DWARF debug info to get the address of TLS variables is not generated yet.
clang and driver changes in http://reviews.llvm.org/D10524
Added -femulated-tls flag to select the emulated TLS model,
which will be used for old targets like Android that do not
support ELF TLS models.
Added TargetLowering::LowerToTLSEmulatedModel as a target-independent
function to convert a SDNode of TLS variable address to a function call
to __emutls_get_address.
Added into lib/Target/*/*ISelLowering.cpp to call LowerToTLSEmulatedModel
for TLSModel::Emulated. Although all targets supporting ELF TLS models are
enhanced, emulated TLS model has been tested only for Android ELF targets.
Modified AsmPrinter.cpp to print the emutls_v.* and emutls_t.* variables for
emulated TLS variables.
Modified DwarfCompileUnit.cpp to skip some DIE for emulated TLS variabls.
TODO: Add proper DIE for emulated TLS variables.
Added new unit tests with emulated TLS.
Differential Revision: http://reviews.llvm.org/D10522
llvm-svn: 243438
Some shufflevectors are currently being incorrectly lowered in the AArch32
backend as the existing checks for detecting the NEON operations from the
shufflevector instruction expects the shuffle mask and the vector operands to be
of the same length.
This is not always the case as the mask may be twice as long as the operand;
here only the lower half of the shufflemask gets checked, so provided the lower
half of the shufflemask looks like a vector transpose (or even is just all -1
for undef) then the intrinsics may get incorrectly lowered into a vector
transpose (VTRN) instruction.
This patch fixes this by accommodating for both cases and adds regression tests.
Differential Revision: http://reviews.llvm.org/D11407
llvm-svn: 243103
is an immediate, in this check the value is negated and stored in and int64_t.
The value can be -2^63 yet the result cannot be stored in an int64_t and this
gives some undefined behaviour causing failures. The negation is only necessary
when the values is within a certain range and so it should not need to negate
-2^63, this patch introduces this and also a regression test.
Differential Revision: http://reviews.llvm.org/D11408
llvm-svn: 243100
llvm.eh.sjlj.setjmp was used as part of the SjLj exception handling
style but is also used in clang to implement __builtin_setjmp. The ARM
backend needs to output additional dispatch tables for the SjLj
exception handling style, these tables however can't be emitted if
llvm.eh.sjlj.setjmp is simply used for __builtin_setjmp and no actual
landing pad blocks exist.
To solve this issue a new llvm.eh.sjlj.setup_dispatch intrinsic is
introduced which is used instead of llvm.eh.sjlj.setjmp in the SjLj
exception handling lowering, so we can differentiate between the case
where we actually need to setup a dispatch table and the case where we
just need the __builtin_setjmp semantic.
Differential Revision: http://reviews.llvm.org/D9313
llvm-svn: 242481
The 64/128-bit vector types are legal if NEON instructions are
available. However, there was no matching patterns for @llvm.cttz.*()
intrinsics and result in fatal error.
This commit fixes the problem by lowering cttz to:
a. ctpop((x & -x) - 1)
b. width - ctlz(x & -x) - 1
llvm-svn: 242037
This patch allows the read_register and write_register intrinsics to
read/write the RBP/EBP registers on X86 iff the targeted register is
the frame pointer for the containing function.
Differential Revision: http://reviews.llvm.org/D10977
llvm-svn: 241827
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
Reviewers: echristo
Subscribers: yaron.keren, rafael, llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11042
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 241779
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
Reviewers: echristo
Subscribers: jholewinski, llvm-commits, rafael, yaron.keren
Differential Revision: http://reviews.llvm.org/D11040
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 241778
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
Reviewers: echristo
Subscribers: jholewinski, ted, yaron.keren, rafael, llvm-commits
Differential Revision: http://reviews.llvm.org/D11028
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 241775
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
Reviewers: echristo
Subscribers: llvm-commits, rafael, yaron.keren
Differential Revision: http://reviews.llvm.org/D11017
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 241655
be emitted.
This is needed to enable ARM long calls for LTO and enable and disable it on a
per-function basis.
Out-of-tree projects currently using EnableARMLongCalls to emit long calls
should start passing "+long-calls" to the feature string (see the changes made
to clang in r241565).
rdar://problem/21529937
Differential Revision: http://reviews.llvm.org/D9364
llvm-svn: 241566
From the linker's perspective, an available_externally global is equivalent
to an external declaration (per isDeclarationForLinker()), so it is incorrect
to consider it to be a weak definition.
Also clean up some logic in the dead argument elimination pass and clarify
its comments to better explain how its behavior depends on linkage,
introduce GlobalValue::isStrongDefinitionForLinker() and start using
it throughout the optimizers and backend.
Differential Revision: http://reviews.llvm.org/D10941
llvm-svn: 241413
There is some functional change here because it changes target code from
atoi(3) to StringRef::getAsInteger which has error checking. For valid
constraints there should be no difference.
llvm-svn: 241411
The patch is generated using this command:
tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
-checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
llvm/lib/
Thanks to Eugene Kosov for the original patch!
llvm-svn: 240137
Currently, we canonicalize shuffles that produce a result larger than
their operands with:
shuffle(concat(v1, undef), concat(v2, undef))
->
shuffle(concat(v1, v2), undef)
because we can access quad vectors (see PerformVECTOR_SHUFFLECombine).
This is useful in the general case, but there are special cases where
native shuffles produce larger results: the two-result ops.
We can look through the concat when lowering them:
shuffle(concat(v1, v2), undef)
->
concat(VZIP(v1, v2):0, :1)
This lets us generate the native shuffles instead of scalarizing to
dozens of VMOVs.
Differential Revision: http://reviews.llvm.org/D10424
llvm-svn: 240118
This reverts commit r239437.
This broke clang-cl self-hosts. We'd end up calling the __imp_ symbol
directly instead of using it to do an indirect function call.
llvm-svn: 239502
that was resetting it.
Remove the uses of DisableTailCalls in subclasses of TargetLowering and use
the value of function attribute "disable-tail-calls" instead. Also,
unconditionally add pass TailCallElim to the pipeline and check the function
attribute at the start of runOnFunction to disable the pass on a per-function
basis.
This is part of the work to remove TargetMachine::resetTargetOptions, and since
DisableTailCalls was the last non-fast-math option that was being reset in that
function, we should be able to remove the function entirely after the work to
propagate IR-level fast-math flags to DAG nodes is completed.
Out-of-tree users should remove the uses of DisableTailCalls and make changes
to attach attribute "disable-tail-calls"="true" or "false" to the functions in
the IR.
rdar://problem/13752163
Differential Revision: http://reviews.llvm.org/D10099
llvm-svn: 239427
This is important because of different addressing modes
depending on the address space for GPU targets.
This only adds the argument, and does not update
any of the uses to provide the correct address space.
llvm-svn: 238723
We were previously codegen'ing these as regular load/store operations and
hoping that the register allocator would allocate registers in ascending order
so that we could apply an LDM/STM combine after register allocation. According
to the commit that first introduced this code (r37179), we planned to teach
the register allocator to allocate the registers in ascending order. This
never got implemented, and up to now we've been stuck with very poor codegen.
A much simpler approach for achiveing better codegen is to create LDM/STM
instructions with identical sets of virtual registers, let the register
allocator pick arbitrary registers and order register lists when printing an
MCInst. This approach also avoids the need to repeatedly calculate offsets
which ultimately ought to be eliminated pre-RA in order to decrease register
pressure.
This is implemented by lowering the memcpy intrinsic to a series of SD-only
MCOPY pseudo-instructions which performs a memory copy using a given number
of registers. During SD->MI lowering, we lower MCOPY to LDM/STM. This is a
little unusual, but it avoids the need to encode register lists in the SD,
and we can take advantage of SD use lists to decide whether to use the _UPD
variant of the instructions.
Fixes PR9199.
Differential Revision: http://reviews.llvm.org/D9508
llvm-svn: 238473
This patch implements LLVM support for the ACLE special register intrinsics in
section 10.1, __arm_{w,r}sr{,p,64}.
This patch is intended to lower the read/write_register instrinsics, used to
implement the special register intrinsics in the clang patch for special
register intrinsics (see http://reviews.llvm.org/D9697), to ARM specific
instructions MRC,MCR,MSR etc. to allow reading an writing of coprocessor
registers in AArch32 and AArch64. This is done by inspecting the register
string passed to the intrinsic and then lowering to the appropriate
instruction.
Patch by Luke Cheeseman.
Differential Revision: http://reviews.llvm.org/D9699
llvm-svn: 237579
We were creating and propagating two separate indices for each jump table (from
back in the mists of time). However, the generic index used by other backends
is sufficient to emit a unique symbol so this was unneeded.
llvm-svn: 237294
to use the information in the module rather than TargetOptions.
We've had and clang has used the use-soft-float attribute for some
time now so have the backends set a subtarget feature based on
a particular function now that subtargets are created based on
functions and function attributes.
For the one middle end soft float check go ahead and create
an overloadable TargetLowering::useSoftFloat function that
just checks the TargetSubtargetInfo in all cases.
Also remove the command line option that hard codes whether or
not soft-float is set by using the attribute for all of the
target specific test cases - for the generic just go ahead and
add the attribute in the one case that showed up.
llvm-svn: 237079
The code that builds the dependence graph assumes that two PseudoSourceValues
don't alias. In a tail calling function two FixedStackObjects might refer to the
same location. Worse 'immutable' fixed stack objects like function arguments are
not immutable and will be clobbered.
Change this so that a load from a FixedStackObject is not invariant in a tail
calling function and don't return a PseudoSourceValue for an instruction in tail
calling functions when building the dependence graph so that we handle function
arguments conservatively.
Fix for PR23459.
rdar://20740035
llvm-svn: 236916
The expansion for t2ABS was always setting the kill flag on the rsb instruction.
It should instead only be set on rsb if it was set on the original ABS instruction.
rdar://problem/20752113
llvm-svn: 236272
[DebugInfo] Add debug locations to constant SD nodes
This adds debug location to constant nodes of Selection DAG and updates
all places that create constants to pass debug locations
(see PR13269).
Can't guarantee that all locations are correct, but in a lot of cases choice
is obvious, so most of them should be. At least all tests pass.
Tests for these changes do not cover everything, instead just check it for
SDNodes, ARM and AArch64 where it's easy to get incorrect locations on
constants.
This is not complete fix as FastISel contains workaround for wrong debug
locations, which drops locations from instructions on processing constants,
but there isn't currently a way to use debug locations from constants there
as llvm::Constant doesn't cache it (yet). Although this is a bit different
issue, not directly related to these changes.
Differential Revision: http://reviews.llvm.org/D9084
llvm-svn: 235989
This adds debug location to constant nodes of Selection DAG and updates
all places that create constants to pass debug locations
(see PR13269).
Can't guarantee that all locations are correct, but in a lot of cases choice
is obvious, so most of them should be. At least all tests pass.
Tests for these changes do not cover everything, instead just check it for
SDNodes, ARM and AArch64 where it's easy to get incorrect locations on
constants.
This is not complete fix as FastISel contains workaround for wrong debug
locations, which drops locations from instructions on processing constants,
but there isn't currently a way to use debug locations from constants there
as llvm::Constant doesn't cache it (yet). Although this is a bit different
issue, not directly related to these changes.
Differential Revision: http://reviews.llvm.org/D9084
llvm-svn: 235977
Because -menable-no-nans causes fcmp conditions to be rewritten
without 'o' or 'u' the recognition code in needs to cope. Also
extended it to handle 'le' and 'ge.
Differential Revision: http://reviews.llvm.org/D8725
llvm-svn: 234421
Summary:
The ARM backend can use a loop to implement copying byval parameters before
a call. In non-thumb2 mode it uses a constant pool load to materialize the
trip count. For targets that need movt instead (e.g. Native Client), use
the same code as in thumb2 mode to materialize the trip count.
Reviewers: jfb, t.p.northover
Differential Revision: http://reviews.llvm.org/D8442
llvm-svn: 233324
Anton tried this 5 years ago but it was reverted due to extra VMOVs
being emitted. This can be easily fixed with a liberal application
of patterns - matching loads/stores and extractelts.
llvm-svn: 232958
Memcpy, and other memory intrinsics, typically tries to use LDM/STM if
the source and target addresses are 4-byte aligned. In CodeGenPrepare
look for calls to memory intrinsics and, if the object is on the
stack, 4-byte align it if it's large enough that we expect that memcpy
would want to use LDM/STM to copy it.
Differential Revision: http://reviews.llvm.org/D7908
llvm-svn: 232627
The main issue being fixed here is that APCS targets handling a "byval align N"
parameter with N > 4 were miscounting what objects were where on the stack,
leading to FrameLowering setting the frame pointer incorrectly and clobbering
the stack.
But byval handling had grown over many years, and had multiple layers of cruft
trying to compensate for each other and calculate padding correctly. This only
really needs to be done once, in the HandleByVal function. Elsewhere should
just do what it's told by that call.
I also stripped out unnecessary APCS/AAPCS distinctions (now that Clang emits
byvals with the correct C ABI alignment), which simplified HandleByVal.
rdar://20095672
llvm-svn: 231959
In theory this allows the compiler to skip materializing the array on
the stack. In practice clang often fails to do that, but that's a
different story. NFC.
llvm-svn: 231571
This commit enables forming vector extloads for ARM.
It only does so for legal types, and when we can't fold the extension
in a wide/long form of the user instruction.
Enabling it for larger types isn't as good an idea on ARM as it is on
X86, because:
- we pretend that extloads are legal, but end up generating vld+vmov
- we have instructions like vld {dN, dM}, which can't be generated
when we "manually expand" extloads to vld+vmov.
For legal types, the combine doesn't fire that often: in the
integration tests only in a big endian testcase, where it removes a
pointless AND.
Related to rdar://19723053
Differential Revision: http://reviews.llvm.org/D7423
llvm-svn: 231396
Summary:
In PNaCl, most atomic instructions have their own @llvm.nacl.atomic.* function, each one, with a few exceptions, represents a consistent behaviour across all NaCl-supported targets. Unfortunately, the atomic RMW operations nand, [u]min, and [u]max aren't directly represented by any such @llvm.nacl.atomic.* function. This patch refines shouldExpandAtomicRMWInIR in TargetLowering so that a future `Le32TargetLowering` class can selectively inform the caller how the target desires the atomic RMW instruction to be expanded (ie via load-linked/store-conditional for ARM/AArch64, via cmpxchg for X86/others?, or not at all for Mips) if at all.
This does not represent a behavioural change and as such no tests were added.
Patch by: Richard Diamond.
Reviewers: jfb
Reviewed By: jfb
Subscribers: jfb, aemerson, t.p.northover, llvm-commits
Differential Revision: http://reviews.llvm.org/D7713
llvm-svn: 231250
a lookup, pass that in rather than use a naked call to getSubtargetImpl.
This involved passing down and around either a TargetMachine or
TargetRegisterInfo. Update all callers/definitions around the targets
and SelectionDAG.
llvm-svn: 230699
This required plumbing a TargetRegisterInfo through computeRegisterProperties
and into findRepresentativeClass which uses it for register class
iteration. This required passing a subtarget into a few target specific
initializations of TargetLowering.
llvm-svn: 230583
The logic is almost there already, with our special homogeneous aggregate
handling. Tweaking it like this allows front-ends to emit AAPCS compliant code
without ever having to count registers or add discarded padding arguments.
Only arrays of i32 and i64 are needed to model AAPCS rules, but I decided to
apply the logic to all integer arrays for more consistency.
llvm-svn: 230348
It was previously using the subtarget to get values for the global
offset without actually checking each function as it was generating
code. Go ahead and solidify the current behavior and make the
existing FIXMEs more prominent.
As a note the ARM backend previously had a thumb1 and non-thumb1
set of defaults. Only the former was tested so I've changed the
behavior to only use that for now.
llvm-svn: 230245
Everyone except R600 was manually passing the length of a static array
at each callsite, calculated in a variety of interesting ways. Far
easier to let ArrayRef handle that.
There should be no functional change, but out of tree targets may have
to tweak their calls as with these examples.
llvm-svn: 230118
This re-applies r223862, r224198, r224203, and r224754, which were
reverted in r228129 because they exposed Clang misalignment problems
when self-hosting.
The combine caused the crashes because we turned ISD::LOAD/STORE nodes
to ARMISD::VLD1/VST1_UPD nodes. When selecting addressing modes, we
were very lax for the former, and only emitted the alignment operand
(as in "[r1:128]") when it was larger than the standard alignment of
the memory type.
However, for ARMISD nodes, we just used the MMO alignment, no matter
what. In our case, we turned ISD nodes to ARMISD nodes, and this
caused the alignment operands to start being emitted.
And that's how we exposed alignment problems that were ignored before
(but I believe would have been caught with SCTRL.A==1?).
To fix this, we can just mirror the hack done for ISD nodes: only
take into account the MMO alignment when the access is overaligned.
Original commit message:
We used to only combine intrinsics, and turn them into VLD1_UPD/VST1_UPD
when the base pointer is incremented after the load/store.
We can do the same thing for generic load/stores.
Note that we can only combine the first load/store+adds pair in
a sequence (as might be generated for a v16f32 load for instance),
because other combines turn the base pointer addition chain (each
computing the address of the next load, from the address of the last
load) into independent additions (common base pointer + this load's
offset).
rdar://19717869, rdar://14062261.
llvm-svn: 229932
In preparation for a future patch:
- rename isLoad to isLoadOp: the former is confusing, and can be taken
to refer to the fact that the node is an ISD::LOAD. (it isn't, yet.)
- change formatting here and there.
- add some comments.
- const-ify bools.
llvm-svn: 229929
This adds a safe interface to the machine independent InputArg struct
for accessing the index of the original (IR-level) argument. When a
non-native return type is lowered, we generate the hidden
machine-level sret argument on-the-fly. Before this fix, we were
representing this argument as OrigArgIndex == 0, which is an outright
lie. In particular this crashed in the AArch64 backend where we
actually try to access the type of the original argument.
Now we use a sentinel value for machine arguments that have no
original argument index. AArch64, ARM, Mips, and PPC now check for this
case before accessing the original argument.
Fixes <rdar://19792160> Null pointer assertion in AArch64TargetLowering
llvm-svn: 229413
Canonicalize access to function attributes to use the simpler API.
getAttributes().getAttribute(AttributeSet::FunctionIndex, Kind)
=> getFnAttribute(Kind)
getAttributes().hasAttribute(AttributeSet::FunctionIndex, Kind)
=> hasFnAttribute(Kind)
llvm-svn: 229220
While various DAG combines try to guarantee that a vector SETCC
operation will have the same output size as input, there's nothing
intrinsic to either creation or LegalizeTypes that actually guarantees
it, so the function needs to be ready to handle a mismatch.
Fortunately this is easy enough, just extend or truncate the naturally
compared result.
I couldn't reproduce the failure in other backends that I know have
SIMD, so it's probably only an issue for these two due to shared
heritage.
Should fix PR21645.
llvm-svn: 228518
This reverts patches 223862, 224198, 224203, and 224754, which were all
related to the vector load/store combining and were reverted/reaplied
a few times due to the same alignment problems we're seeing now.
Further tests, mainly self-hosting Clang, will be needed to reapply this
patch in the future.
llvm-svn: 228129
type (in addition to the memory type).
The *LoadExt* legalization handling used to only have one type, the
memory type. This forced users to assume that as long as the extload
for the memory type was declared legal, and the result type was legal,
the whole extload was legal.
However, this isn't always the case. For instance, on X86, with AVX,
this is legal:
v4i32 load, zext from v4i8
but this isn't:
v4i64 load, zext from v4i8
Whereas v4i64 is (arguably) legal, even without AVX2.
Note that the same thing was done a while ago for truncstores (r46140),
but I assume no one needed it yet for extloads, so here we go.
Calls to getLoadExtAction were changed to add the value type, found
manually in the surrounding code.
Calls to setLoadExtAction were mechanically changed, by wrapping the
call in a loop, to match previous behavior. The loop iterates over
the MVT subrange corresponding to the memory type (FP vectors, etc...).
I also pulled neighboring setTruncStoreActions into some of the loops;
those shouldn't make a difference, as the additional types are illegal.
(e.g., i128->i1 truncstores on PPC.)
No functional change intended.
Differential Revision: http://reviews.llvm.org/D6532
llvm-svn: 225421
Weak externals are resolved statically, so we can actually generate the tail
call on PE/COFF targets without breaking the requirements. It is questionable
whether we want to propagate the current behaviour for MachO as the requirements
are part of the ARM ELF specifications, and it seems that prior to the SVN
r215890, we would have tail'ed the call. For now, be conservative and only
permit it on PE/COFF where the call will always be fully resolved.
llvm-svn: 225119
r223862/r224203 tried to also combine base-updating load/stores.
There was a mistake there: the alignment was added as is as an operand to
the ARMISD::VLD/VST node. However, the VLD/VST selection logic doesn't care
about less-than-standard alignment attributes.
For example, no matter the alignment of a v2i64 load (say 1), SelectVLD picks
VLD1q64 (because of the memory type). But VLD1q64 ("vld1.64 {dXX, dYY}") is
8-aligned, per ARMARMv7a 3.2.1.
For the 1-aligned load, what we really want is VLD1q8.
This commit introduces bitcasts if necessary, and changes the vld/vst type to
one whose standard alignment matches the original load/store alignment.
Differential Revision: http://reviews.llvm.org/D6759
llvm-svn: 224754
Add in definedness checks for shift operators, null checks when
pointers are assumed by the code to be non-null, and explicit
unreachables.
llvm-svn: 224255
r223862 tried to also combine base-updating load/stores.
r224198 reverted it, as "it created a regression on the test-suite
on test MultiSource/Benchmarks/Ptrdist/anagram by scrambling the order
in which the words are shown."
Reapply, with a fix to ignore non-normal load/stores.
Truncstores are handled elsewhere (you can actually write a pattern for
those, whereas for postinc loads you can't, since they return two values),
but it should be possible to also combine extloads base updates, by checking
that the memory (rather than result) type is of the same size as the addend.
Original commit message:
We used to only combine intrinsics, and turn them into VLD1_UPD/VST1_UPD
when the base pointer is incremented after the load/store.
We can do the same thing for generic load/stores.
Note that we can only combine the first load/store+adds pair in
a sequence (as might be generated for a v16f32 load for instance),
because other combines turn the base pointer addition chain (each
computing the address of the next load, from the address of the last
load) into independent additions (common base pointer + this load's
offset).
Differential Revision: http://reviews.llvm.org/D6585
llvm-svn: 224203
This reverts commit r223862, as it created a regression on the test-suite
on test MultiSource/Benchmarks/Ptrdist/anagram by scrambling the order
in which the words are shown. We'll investigate the issue and re-apply
when safe.
llvm-svn: 224198
We used to only combine intrinsics, and turn them into VLD1_UPD/VST1_UPD
when the base pointer is incremented after the load/store.
We can do the same thing for generic load/stores.
Note that we can only combine the first load/store+adds pair in
a sequence (as might be generated for a v16f32 load for instance),
because other combines turn the base pointer addition chain (each
computing the address of the next load, from the address of the last
load) into independent additions (common base pointer + this load's
offset).
Differential Revision: http://reviews.llvm.org/D6585
llvm-svn: 223862
Move the combiner-state check into another function, add a few
small comments, and use a more general type in a cast<>.
In preparation for a future patch.
llvm-svn: 223834
This is to be consistent with StringSet and ultimately with the standard
library's associative container insert function.
This lead to updating SmallSet::insert to return pair<iterator, bool>,
and then to update SmallPtrSet::insert to return pair<iterator, bool>,
and then to update all the existing users of those functions...
llvm-svn: 222334
register class tGPRRegClass if the target is thumb1.
This commit fixes a crash that occurs during register allocation which was
triggered when a virtual register defined by an inline-asm instruction had to
be spilled.
rdar://problem/18740489
llvm-svn: 221178
This patch adds an optimization in CodeGenPrepare to move an extractelement
right before a store when the target can combine them.
The optimization may promote any scalar operations to vector operations in the
way to make that possible.
** Context **
Some targets use different register files for both vector and scalar operations.
This means that transitioning from one domain to another may incur copy from one
register file to another. These copies are not coalescable and may be expensive.
For example, according to the scheduling model, on cortex-A8 a vector to GPR
move is 20 cycles.
** Motivating Example **
Let us consider an example:
define void @foo(<2 x i32>* %addr1, i32* %dest) {
%in1 = load <2 x i32>* %addr1, align 8
%extract = extractelement <2 x i32> %in1, i32 1
%out = or i32 %extract, 1
store i32 %out, i32* %dest, align 4
ret void
}
As it is, this IR generates the following assembly on armv7:
vldr d16, [r0] @vector load
vmov.32 r0, d16[1] @ cross-register-file copy: 20 cycles
orr r0, r0, #1 @ scalar bitwise or
str r0, [r1] @ scalar store
bx lr
Whereas we could generate much faster code:
vldr d16, [r0] @ vector load
vorr.i32 d16, #0x1 @ vector bitwise or
vst1.32 {d16[1]}, [r1:32] @ vector extract + store
bx lr
Half of the computation made in the vector is useless, but this allows to get
rid of the expensive cross-register-file copy.
** Proposed Solution **
To avoid this cross-register-copy penalty, we promote the scalar operations to
vector operations. The penalty will be removed if we manage to promote the whole
chain of computation in the vector domain.
Currently, we do that only when the chain of computation ends by a store and the
target is able to combine an extract with a store.
Stores are the most likely candidates, because other instructions produce values
that would need to be promoted and so, extracted as some point[1]. Moreover,
this is customary that targets feature stores that perform a vector extract (see
AArch64 and X86 for instance).
The proposed implementation relies on the TargetTransformInfo to decide whether
or not it is beneficial to promote a chain of computation in the vector domain.
Unfortunately, this interface is rather inaccurate for this level of details and
although this optimization may be beneficial for X86 and AArch64, the inaccuracy
will lead to the optimization being too aggressive.
Basically in TargetTransformInfo, everything that is legal has a cost of 1,
whereas, even if a vector type is legal, usually a vector operation is slightly
more expensive than its scalar counterpart. That will lead to too many
promotions that may not be counter balanced by the saving of the
cross-register-file copy. For instance, on AArch64 this penalty is just 4
cycles.
For now, the optimization is just enabled for ARM prior than v8, since those
processors have a larger penalty on cross-register-file copies, and the scope is
limited to basic blocks. Because of these two factors, we limit the effects of
the inaccuracy. Indeed, I did not want to build up a fancy cost model with block
frequency and everything on top of that.
[1] We can imagine targets that can combine an extractelement with other
instructions than just stores. If we want to go into that direction, the current
interfaces must be augmented and, moreover, I think this becomes a global isel
problem.
Differential Revision: http://reviews.llvm.org/D5921
<rdar://problem/14170854>
llvm-svn: 220978
Currently, the ARM backend will select the VMAXNM and VMINNM for these C
expressions:
(a < b) ? a : b
(a > b) ? a : b
but not these expressions:
(a > b) ? b : a
(a < b) ? b : a
This patch allows all of these expressions to be matched.
llvm-svn: 220671
This updates check for double precision zero floating point constant to allow
use of instruction with immediate value rather than temporary register.
Currently "a == 0.0", where "a" is of "double" type generates:
vmov.i32 d16, #0x0
vcmpe.f64 d0, d16
With this change it becomes:
vcmpe.f64 d0, #0
Patch by Sergey Dmitrouk.
llvm-svn: 220486
The previous code had a few problems, motivating the choices here.
1. It could create instructions clobbering CPSR, but the incoming MachineInstr
didn't reflect this. A potential source of corruption. This is why the patch
has a new PseudoInst for before lowering.
2. Similarly, there was some code to handle the incoming instruction not being
ARMCC::AL, but this would have caused massive problems if it was actually
invoked when a complex offset needing more than one instruction was requested.
3. It wasn't designed to handle unaligned pointers (or offsets). These should
probably be minimised anyway, but the code needs to deal with them properly
regardless.
4. It had some rather dubious ad-hoc code to avoid calling
emitThumbRegPlusImmediate, a function which should be designed to do precisely
this job.
We seem to cover the common cases correctly now, and hopefully can enhance
emitThumbRegPlusImmediate to handle any extra optimisations we need to add in
future.
llvm-svn: 220236
Currently, we only codegen the VRINT[APMXZR] and VCVT[BT] instructions
when targeting ARMv8, but they are actually present on any target with
FP-ARMv8. Note that FP-ARMv8 is called FPv5 when is is part of an
M-profile core, but they have the same instructions so we model them
both as FPARMv8 in the ARM backend.
llvm-svn: 218763
Summary:
The goal is to eventually remove all the code related to getInsertFencesForAtomic
in SelectionDAGBuilder as it is wrong (designed for ARM, not really portable, works
mostly by accident because the backends are overly conservative), and repeats the
same logic that goes in emitLeading/TrailingFence.
In this patch, I make AtomicExpandPass insert the fences as it knows better
where to put them. Because this requires getting the fences and not just
passing an IRBuilder around, I had to change the return type of
emitLeading/TrailingFence.
This code only triggers on ARM for now. Because it is earlier in the pipeline
than SelectionDAGBuilder, it triggers and lowers atomic accesses to atomic so
SelectionDAGBuilder does not add barriers anymore on ARM.
If this patch is accepted I plan to implement emitLeading/TrailingFence for all
backends that setInsertFencesForAtomic(true), which will allow both making them
less conservative and simplifying SelectionDAGBuilder once they are all using
this interface.
This should not cause any functionnal change so the existing tests are used
and not modified.
Test Plan: make check-all, benefits from existing tests of atomics on ARM
Reviewers: jfb, t.p.northover
Subscribers: aemerson, llvm-commits
Differential Revision: http://reviews.llvm.org/D5179
llvm-svn: 218329
The fix is slightly different then x86 (see r216117) because the number of values
attached to a return can vary even for a single returned value (e.g., f64 yields
two returned values).
<rdar://problem/18352998>
llvm-svn: 218076
Summary:
This patch was originally in D5304 (I could not find a way to reopen that revision).
It was accepted, commited and broke the build bots because the overloading of
the constructor of ArrayRef for braced initializer lists is not supported by all
toolchains. I then reverted it, and propose this fixed version that uses a plain
C array instead in makeDMB (that array is then converted implicitly to an
ArrayRef, but that is not behind an ifdef). Could someone confirm me whether
initialization lists for plain C arrays are supported by every toolchain used
to build llvm ? Otherwise I can just initialize the array in the old way:
args[0] = ...; .. ; args[5] = ...;
Below is the description of the original patch:
```
I had only tested this code for ARMv7 and ARMv8. This patch adds several
fallback paths if the processor does not support dmb ish:
- dmb sy if a cortex-M with support for dmb
- mcr p15, #0, r0, c7, c10, #5 for ARMv6 (special instruction equivalent to a DMB)
These fallback paths were chosen based on the code for fence seq_cst.
Thanks to luqmana for having noticed this bug.
```
Test Plan: Added more cases to atomic-load-store.ll + make check-all
Reviewers: jfb, t.p.northover, luqmana
Subscribers: llvm-commits, aemerson
Differential Revision: http://reviews.llvm.org/D5386
llvm-svn: 218066
It is breaking the build on the buildbots but works fine on my machine, I revert
while trying to understand what happens (it appears to depend on the compiler used
to build, I probably used a C++11 feature that is not perfectly supported by some
of the buildbots).
This reverts commit feb3176c4d006f99af8b40373abd56215a90e7cc.
llvm-svn: 217973
Summary:
I had only tested this code for ARMv7 and ARMv8. This patch adds several
fallback paths if the processor does not support dmb ish:
- dmb sy if a cortex-M with support for dmb
- mcr p15, #0, r0, c7, c10, #5 for ARMv6 (special instruction equivalent to a DMB)
These fallback paths were chosen based on the code for fence seq_cst.
Thanks to luqmana for having noticed this bug.
Test Plan: Added more cases to atomic-load-store.ll + make check-all
Reviewers: jfb, t.p.northover, luqmana
Subscribers: aemerson, llvm-commits
Differential Revision: http://reviews.llvm.org/D5304
llvm-svn: 217965
This required a new hook called hasLoadLinkedStoreConditional to know whether
to expand atomics to LL/SC (ARM, AArch64, in a future patch Power) or to
CmpXchg (X86).
Apart from that, the new code in AtomicExpandPass is mostly moved from
X86AtomicExpandPass. The main result of this patch is to get rid of that
pass, which had lots of code duplicated with AtomicExpandPass.
llvm-svn: 217928
Summary:
Split shouldExpandAtomicInIR() into different versions for Stores/Loads/RMWs/CmpXchgs.
Makes runOnFunction cleaner (no more redundant checking/casting), and will help moving
the X86 backend to this pass.
This requires a way of easily detecting which instructions are atomic.
I followed the pattern of mayReadFromMemory, mayWriteOrReadMemory, etc.. in making
isAtomic() a method of Instruction implemented by a switch on the opcodes.
Test Plan: make check
Reviewers: jfb
Subscribers: mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D5035
llvm-svn: 217080
Fixes two latent bugs:
- There was no fence inserted before expanded seq_cst load (unsound on Power)
- There was only a fence release before seq_cst stores (again unsound, in particular on Power)
It is not even clear if this is correct on ARM swift processors (where release fences are
DMB ishst instead of DMB ish). This behaviour is currently preserved on ARM Swift
as it is not clear whether it is incorrect. I would love to get documentation stating
whether it is correct or not.
These two bugs were not triggered because Power is not (yet) using this pass, and these
behaviours happen to be (mostly?) working on ARM
(although they completely butchered the semantics of the llvm IR).
See:
http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-August/075821.html
for an example of the problems that can be caused by the second of these bugs.
I couldn't see a way of fixing these in a completely target-independent way without
adding lots of unnecessary fences on ARM, hence the target-dependent parts of this
patch.
This patch implements the new target-dependent parts only for ARM (the default
of not doing anything is enough for AArch64), other architectures will use this
infrastructure in later patches.
llvm-svn: 217076
Saleem Abdulrasool