This is mostly achieved by providing the correct register class manually,
because getRegClassFor always returns the GPR*AllRegClass for MVT::i32 and
MVT::i64.
Also cleanup the code to use the FastEmitInst_* method whenever possible. This
makes sure that the operands' register class is properly constrained. For all
the remaining cases this adds the missing constrainOperandRegClass calls for
each operand.
llvm-svn: 216225
The AdvSIMD pass may produce copies that are not coalescer-friendly. The
peephole optimizer knows how to fix that as demonstrated in the test case.
<rdar://problem/12702965>
llvm-svn: 216200
This fixes a bug I introduced in a previous commit (r216033). Sign-/Zero-
extension from i1 cannot be folded into the ADDS/SUBS instructions. Instead both
operands have to be sign-/zero-extended with separate instructions.
Related to <rdar://problem/17913111>.
llvm-svn: 216073
legalization stage. With those two optimizations, fewer signed/zero extension
instructions can be inserted, and then we can expose more opportunities to
Machine CSE pass in back-end.
llvm-svn: 216066
LLVM generates illegal `rbit r0, #352` instruction for rbit intrinsic.
According to ARM ARM, rbit only takes register as argument, not immediate.
The correct instruction should be rbit <Rd>, <Rm>.
The bug was originally introduced in r211057.
Differential Revision: http://reviews.llvm.org/D4980
llvm-svn: 216064
Use FMOVWSr/FMOVXDr instead of FMOVSr/FMOVDr, which have the proper register
class to be used with the zero register. This makes the MachineInstruction
verifier happy again.
This is related to <rdar://problem/18027157>.
llvm-svn: 216040
Factor out the ADDS/SUBS instruction emission code into helper functions and
make the helper functions more clever to support most of the different ADDS/SUBS
instructions the architecture support. This includes better immedediate support,
shift folding, and sign-/zero-extend folding.
This fixes <rdar://problem/17913111>.
llvm-svn: 216033
This adds the missing test that I promised for r215753 to test the
materialization of the floating-point value +0.0.
Related to <rdar://problem/18027157>.
llvm-svn: 216019
Note: This was originally reverted to track down a buildbot error. Reapply
without any modifications.
Original commit message:
FastISel didn't take much advantage of the different addressing modes available
to it on AArch64. This commit allows the ComputeAddress method to recognize more
addressing modes that allows shifts and sign-/zero-extensions to be folded into
the memory operation itself.
For Example:
lsl x1, x1, #3 --> ldr x0, [x0, x1, lsl #3]
ldr x0, [x0, x1]
sxtw x1, w1
lsl x1, x1, #3 --> ldr x0, [x0, x1, sxtw #3]
ldr x0, [x0, x1]
llvm-svn: 216013
Note: This was originally reverted to track down a buildbot error. Reapply
without any modifications.
Original commit message:
This change materializes now the value "0" from the zero register.
The zero register can be folded by several instruction, so no
materialization is need at all.
Fixes <rdar://problem/17924413>.
llvm-svn: 216009
This fixes a few BuildMI callsites where the result register was added by
using addReg, which is per default a use and therefore an operand register.
Also use the zero register as result register when emitting a compare
instruction (SUBS with unused result register).
llvm-svn: 215997
Externally-defined functions with weak linkage should not be
tail-called on ARM or AArch64, as the AAELF spec requires normal calls
to undefined weak functions to be replaced with a NOP or jump to the
next instruction. The behaviour of branch instructions in this
situation (as used for tail calls) is implementation-defined, so we
cannot rely on the linker replacing the tail call with a return.
llvm-svn: 215890
This reverts:
r215595 "[FastISel][X86] Add large code model support for materializing floating-point constants."
r215594 "[FastISel][X86] Use XOR to materialize the "0" value."
r215593 "[FastISel][X86] Emit more efficient instructions for integer constant materialization."
r215591 "[FastISel][AArch64] Make use of the zero register when possible."
r215588 "[FastISel] Let the target decide first if it wants to materialize a constant."
r215582 "[FastISel][AArch64] Cleanup constant materialization code. NFCI."
llvm-svn: 215673
Certain functions such as objc_autoreleaseReturnValue have to be called as
tail-calls even at -O0. Since normal fast-isel doesn't emit calls as tail calls,
we have to fall back to SelectionDAG to select calls that are marked as tail.
<rdar://problem/17991614>
llvm-svn: 215600
FastISel didn't take much advantage of the different addressing modes available
to it on AArch64. This commit allows the ComputeAddress method to recognize more
addressing modes that allows shifts and sign-/zero-extensions to be folded into
the memory operation itself.
For Example:
lsl x1, x1, #3 --> ldr x0, [x0, x1, lsl #3]
ldr x0, [x0, x1]
sxtw x1, w1
lsl x1, x1, #3 --> ldr x0, [x0, x1, sxtw #3]
ldr x0, [x0, x1]
llvm-svn: 215597
This change materializes now the value "0" from the zero register.
The zero register can be folded by several instruction, so no
materialization is need at all.
Fixes <rdar://problem/17924413>.
llvm-svn: 215591
The combiner ignored DBG nodes when checking
the uses of a virtual register.
It combined a sequence like
%vreg1 = madd %vreg2, %vreg3,...
DBG_VALUE (%vreg1 ...)
%vreg4 = add %vreg1,...
to
%vreg4 = madd %vreg2, %vreg3
leaving behind a dangling DBG_VALUE with
a definition. This triggered an assertion
in the MachineTraceMetrics.cpp module.
llvm-svn: 215431
be propagated to all its users, and this propagation could increase the
probability of finding common subexpressions. If the COPY has only one user,
the COPY itself can be removed.
llvm-svn: 215344
For best-case performance on Cortex-A57, we should try to use a balanced mix of odd and even D-registers when performing a critical sequence of independent, non-quadword FP/ASIMD floating-point multiply or multiply-accumulate operations.
This pass attempts to detect situations where the register allocation may adversely affect this load balancing and to change the registers used so as to better utilize the CPU.
Ideally we'd just take each multiply or multiply-accumulate in turn and allocate it alternating even or odd registers. However, multiply-accumulates are most efficiently performed in the same functional unit as their accumulation operand. Therefore this pass tries to find maximal sequences ("Chains") of multiply-accumulates linked via their accumulation operand, and assign them all the same "color" (oddness/evenness).
This optimization affects S-register and D-register floating point multiplies and FMADD/FMAs, as well as vector (floating point only) muls and FMADD/FMA. Q register instructions (and 128-bit vector instructions) are not affected.
llvm-svn: 215199
This short-circuited our error reporting for incorrectly specified
target triples (you'd get AArch64 code instead).
Should fix PR20567.
llvm-svn: 215191
__stack_chk_guard.
Handle the case where the pointer operand of the load instruction that loads the
stack guard is not a global variable but instead a bitcast.
%StackGuard = load i8** bitcast (i64** @__stack_chk_guard to i8**)
call void @llvm.stackprotector(i8* %StackGuard, i8** %StackGuardSlot)
Original test case provided by Ana Pazos.
This fixes PR20558.
llvm-svn: 215167
Re-commit of r214832,r21469 with a work-around that
avoids the previous problem with gcc build compilers
The work-around is to use SmallVector instead of ArrayRef
of basic blocks in preservesResourceLen()/MachineCombiner.cpp
llvm-svn: 215151
Instruction prefetch is not implemented for AArch64, it is incorrectly
translated into data prefetch instruction.
Differential Revision: http://reviews.llvm.org/D4777
llvm-svn: 214860
This implements basic argument lowering for AArch64 in FastISel. It only
handles a small subset of the C calling convention. It supports simple
arguments that can be passed in GPR and FPR registers.
This should cover most of the trivial cases without falling back to
SelectionDAG.
This fixes <rdar://problem/17890986>.
llvm-svn: 214846
sequence on AArch64
Re-commit of r214669 without changes to test cases
LLVM::CodeGen/AArch64/arm64-neon-mul-div.ll and
LLVM:: CodeGen/AArch64/dp-3source.ll
This resolves the reported compfails of the original commit.
llvm-svn: 214832
This fix changes the parameters #r and #s that are passed to the UBFM/SBFM
instruction to get the zero/sign-extension for free.
The original problem was that the shift left would use the 32-bit shift even for
i8/i16 value types, which could leave the upper bits set with "garbage" values.
The arithmetic shift right on the other side would use the wrong MSB as sign-bit
to determine what bits to shift into the value.
This fixes <rdar://problem/17907720>.
llvm-svn: 214788
scalar integer instruction pass.
This is a patch I had lying around from a few months ago. The pass is
currently disabled by default, so nothing to interesting.
llvm-svn: 214779
sequence - AArch64 target support
This patch turns off madd/msub generation in the DAGCombiner and generates
them in the MachineCombiner instead. It replaces the original code sequence
with the combined sequence when it is beneficial to do so.
When there is no machine model support it always generates the madd/msub
instruction. This is true also when the objective is to optimize for code
size: when the combined sequence is shorter is always chosen and does not
get evaluated.
When there is a machine model the combined instruction sequence
is evaluated for critical path and resource length using machine
trace metrics and the original code sequence is replaced when it is
determined to be faster.
rdar://16319955
llvm-svn: 214669
Add branch weights to branch instructions, so that the following passes can
optimize based on it (i.e. basic block ordering).
Fixes <rdar://problem/17887137>.
llvm-svn: 214537
The tbz/tbnz checks the sign bit to convert
op w1, w1, w10
cmp w1, #0
b.lt .LBB0_0
to
op w1, w1, w10
tbnz w1, #31, .LBB0_0
Differential Revision: http://reviews.llvm.org/D4440
llvm-svn: 214518
ADDS and SUBS cannot encode negative immediates or immediates larger than 12bit.
This fix checks if the immediate version can be used under this constraints and
if we can convert ADDS to SUBS or vice versa to support negative immediates.
Also update the test cases to test the immediate versions.
llvm-svn: 214470
This commit updates the existing SelectionDAG tests for the stackmap and patchpoint
intrinsics and enables FastISel testing. It also splits up the tests into separate
files, due to different codegen between SelectionDAG and FastISel.
llvm-svn: 214382
Currently the large code model for MachO uses the GOT to make function calls.
Emit the required adrp and ldr instructions to load the address from the GOT.
Related to <rdar://problem/17733076>.
llvm-svn: 214381
This improves the code generation for the XALU intrinsics when the
condition is feeding a select instruction.
This also updates and enables the XALU unit tests for FastISel.
This fixes <rdar://problem/17831117>.
llvm-svn: 214350
Currently the shift-immediate versions are not supported by tblgen and
hopefully this can be later removed, once the required support has been
added to tblgen.
llvm-svn: 214345
'J' represents a negative number suitable for an add/sub alias
instruction, but while preparing it to become an int64_t we were
mangling the sign extension. So "i32 -1" became 0xffffffffLL, for
example.
Should fix one half of PR20456.
llvm-svn: 214052
address of the stack guard was being spilled to the stack.
Previously the address of the stack guard would get spilled to the stack if it
was impossible to keep it in a register. This patch introduces a new target
independent node and pseudo instruction which gets expanded post-RA to a
sequence of instructions that load the stack guard value. Register allocator
can now just remat the value when it can't keep it in a register.
<rdar://problem/12475629>
llvm-svn: 213967
This commit implements the frameaddress intrinsic for the AArch64 architecture
in FastISel.
There were two test cases that pretty much tested the same, so I combined them
to a single test case.
Fixes <rdar://problem/17811834>
llvm-svn: 213959
which have successfully round-tripped through the combine phase, and use
this to ensure all operands to DAG nodes are visited by the combiner,
even if they are only added during the combine phase.
This is critical to have the combiner reach nodes that are *introduced*
during combining. Previously these would sometimes be visited and
sometimes not be visited based on whether they happened to end up on the
worklist or not. Now we always run them through the combiner.
This fixes quite a few bad codegen test cases lurking in the suite while
also being more principled. Among these, the TLS codegeneration is
particularly exciting for programs that have this in the critical path
like TSan-instrumented binaries (although I think they engineer to use
a different TLS that is faster anyways).
I've tried to check for compile-time regressions here by running llc
over a merged (but not LTO-ed) clang bitcode file and observed at most
a 3% slowdown in llc. Given that this is essentially a worst case (none
of opt or clang are running at this phase) I think this is tolerable.
The actual LTO case should be even less costly, and the cost in normal
compilation should be negligible.
With this combining logic, it is possible to re-legalize as we combine
which is necessary to implement PSHUFB formation on x86 as
a post-legalize DAG combine (my ultimate goal).
Differential Revision: http://reviews.llvm.org/D4638
llvm-svn: 213898
This bug is introduced by r211144. The element of operand may be
smaller than the element of result, but previous commit can
only handle the contrary condition. This commit is to handle this
scenario and generate optimized codes like ZIP1.
llvm-svn: 213830
The transform to constant fold unary operations with an AND across a
vector comparison applies when the constant is not a splat of a scalar
as well.
llvm-svn: 213800
The folding of unary operations through a vector compare and mask operation
is only safe if the unary operation result is of the same size as its input.
For example, it's not safe for [su]itofp from v4i32 to v4f64.
llvm-svn: 213799
I used the wrong method to obtain the return type inside FinishCall. This fix
simply uses the return type from FastLowerCall, which we already determined to
be a valid type.
Reduced test case from Chad. Thanks.
llvm-svn: 213788
The target-independent DAGcombiner will generate:
asr w1, X, #31 w1 = splat sign bit.
add X, X, w1, lsr #28 X = X + 0 or pow2-1
asr w0, X, asr #4 w0 = X/pow2
However, the add + shifts is expensive, so generate:
add w0, X, 15 w0 = X + pow2-1
cmp X, wzr X - 0
csel X, w0, X, lt X = (X < 0) ? X + pow2-1 : X;
asr w0, X, asr 4 w0 = X/pow2
llvm-svn: 213758
There really is no arm64_be: it was a useful fiction to test big-endian support
while both backends existed in parallel, but now the only platform that uses
the name (iOS) doesn't have a big-endian variant, let alone one called
"arm64_be".
llvm-svn: 213748
This commit modifies the existing call lowering functions to be used as the
FastLowerCall and FastLowerIntrinsicCall target-hooks instead.
This enables patchpoint intrinsic lowering for AArch64.
This fixes <rdar://problem/17733076>
llvm-svn: 213704
This makes the first stage DAG for @llvm.convert.to.fp16 an fptrunc,
and correspondingly @llvm.convert.from.fp16 an fpext. The legalisation
path is now uniform, regardless of the input IR:
fptrunc -> FP_TO_FP16 (if f16 illegal) -> libcall
fpext -> FP16_TO_FP (if f16 illegal) -> libcall
Each target should be able to select the version that best matches its
operations and not be required to duplicate patterns for both fptrunc
and FP_TO_FP16 (for example).
As a result we can remove some redundant AArch64 patterns.
llvm-svn: 213507
Because i16 is illegal, there's no native DAG method to
represent a bitcast to or from an f16 type. This meant LLVM was
inserting a stack store/load pair which is really not ideal.
llvm-svn: 213378
Actual support for softening f16 operations is still limited, and can be added
when it's needed. But Soften is much closer to being a useful thing to try
than keeping it Legal when no registers can actually hold such values.
Longer term, we probably want something between Soften and Promote semantics
for most targets, it'll be more efficient to promote the 4 basic operations to
f32 than libcall them.
llvm-svn: 213372
Since the result of a SETCC for AArch64 is 0 or -1 in each lane, we can
move unary operations, in this case [su]int_to_fp through the mask
operation and constant fold the operation away. Generally speaking:
UNARYOP(AND(VECTOR_CMP(x,y), constant))
--> AND(VECTOR_CMP(x,y), constant2)
where constant2 is UNARYOP(constant).
This implements the transform where UNARYOP is [su]int_to_fp.
For example, consider the simple function:
define <4 x float> @foo(<4 x float> %val, <4 x float> %test) nounwind {
%cmp = fcmp oeq <4 x float> %val, %test
%ext = zext <4 x i1> %cmp to <4 x i32>
%result = sitofp <4 x i32> %ext to <4 x float>
ret <4 x float> %result
}
Before this change, the code is generated as:
fcmeq.4s v0, v0, v1
movi.4s v1, #0x1 // Integer splat value.
and.16b v0, v0, v1 // Mask lanes based on the comparison.
scvtf.4s v0, v0 // Convert each lane to f32.
ret
After, the code is improved to:
fcmeq.4s v0, v0, v1
fmov.4s v1, #1.00000000 // f32 splat value.
and.16b v0, v0, v1 // Mask lanes based on the comparison.
ret
The svvtf.4s has been constant folded away and the floating point 1.0f
vector lanes are materialized directly via fmov.4s.
Rather than do the folding manually in the target code, teach getNode()
in the generic SelectionDAG to handle folding constant operands of
vector [su]int_to_fp nodes. It is reasonable (as noted in a FIXME) to do
additional constant folding there as well, but I don't have test cases
for those operations, so leaving them for another time when it becomes
appropriate.
rdar://17693791
llvm-svn: 213341
This makes the two intrinsics @llvm.convert.from.f16 and
@llvm.convert.to.f16 accept types other than simple "float". This is
only strictly needed for the truncate operation, since otherwise
double rounding occurs and there's no way to represent the strict IEEE
conversion. However, for symmetry we allow larger types in the extend
too.
During legalization, we can expand an "fp16_to_double" operation into
two extends for convenience, but abort when the truncate isn't legal. A new
libcall is probably needed here.
Even after this commit, various target tweaks are needed to actually use the
extended intrinsics. I've put these into separate commits for clarity, so there
are no actual tests of f64 conversion here.
llvm-svn: 213248
Memory barrier __builtin_arm_[dmb, dsb, isb] intrinsics are required to
implement their corresponding ACLE and MSVC intrinsics.
This patch ports ARM dmb, dsb, isb intrinsic to AArch64.
Differential Revision: http://reviews.llvm.org/D4520
llvm-svn: 213247
This adds a llvm.aarch64.hint intrinsic to mirror the llvm.arm.hint in order to
support the various hint intrinsic functions in the ACLE.
Add an optional pattern field that permits the subclass to specify the pattern
that matches the selection. The intrinsic pattern is set as mayLoad, mayStore,
so overload the value for the definition of the hint instruction.
llvm-svn: 212883
Storing will generally be immediately preceded by rounding from an f32
or f64, so make sure to match those patterns directly to convert into the
FPR16 register class directly rather than going through the integer GPRs.
This also eliminates an extra step in the convert-from-f64 path
which was first converting to f32 and then to f16 from there.
rdar://17594379
llvm-svn: 212638
Loading will generally extend to an f32 or an 64, so make sure
to match those patterns directly to load into the FPR16 register
class directly rather than going through the integer GPRs.
This also eliminates an extra step in the convert-to-f64 path
which was first converting to f32 and then to f64 from there.
rdar://17594379
llvm-svn: 212573
Currently AArch64FastISel crashes if it tries to extend an integer into an
MVT::i128. This can happen by creating 128 bit integers like so:
typedef unsigned int uint128_t __attribute__((mode(TI)));
typedef int sint128_t __attribute__((mode(TI)));
This patch makes EmitIntExt check for their presence and then falls back to
SelectionDAG.
Tests included.
rdar://17516686
llvm-svn: 212492
We've been performing the wrong operation on ARM for "atomicrmw nand" for
years, since "a NAND b" is "~(a & b)" rather than ARM's very tempting "a & ~b".
This bled over into the generic expansion pass.
So I assume no-one has ever actually tried to do an atomic nand in the real
world. Oh well.
llvm-svn: 212443
vector type legalization strategies in a more fine grained manner, and
change the legalization of several v1iN types and v1f32 to be widening
rather than scalarization on AArch64.
This fixes an assertion failure caused by scalarizing nodes like "v1i32
trunc v1i64". As v1i64 is legal it will fail to scalarize v1i32.
This also provides a foundation for other targets to have more granular
control over how vector types are legalized.
Patch by Hao Liu, reviewed by Tim Northover. I'm committing it to allow
some work to start taking place on top of this patch as it adds some
really important hooks to the backend that I'd like to immediately start
using. =]
http://reviews.llvm.org/D4322
llvm-svn: 212242
This reverts commits r212189 and r212190.
While this pass was accidentally disabled (until r212073), r205437
slipped in a use of `auto` that should have been `auto&`.
This fixes PR20188.
llvm-svn: 212201
This reverts commit r212109, which reverted r212088.
However, disable the assert as it's not necessary for correctness. There are
several corner cases that the assert needed to handle better for in-order
scheduling, but none of them are incorrect scheduler behavior. The assert is
mainly there to collect good unit tests like this and ensure that the
target-independent scheduler is working as expected with the various machine
models.
llvm-svn: 212187
AArch64AddressTypePromotion was doing nothing because it was using the
old semantics of `Use` and `uses()`, when it really wanted to get at the
`users()`.
llvm-svn: 212073
Fixe for Bug 20057 - Assertion failied in llvm::SUnit* llvm::SchedBoundary::pickOnlyChoice(): Assertion `i <= (HazardRec->getMaxLookAhead() + MaxObservedStall) && "permanent hazard"'
Thanks to Chad for the test case.
llvm-svn: 211865
ReconstructShuffle() may wrongly creat a CONCAT_VECTOR trying to
concat 2 of v2i32 into v4i16. This commit is to fix this issue and
try to generate UZP1 instead of lots of MOV and INS.
Patch is initalized by Kevin Qin, and refactored by Tim Northover.
llvm-svn: 211144
To make sure branches are in range, we need to do a better job of estimating
the length of an inline assembly block than "it's probably 1 instruction, who'd
write asm with more than that?".
Fortunately there's already a (highly suspect, see how many ways you can think
of to break it!) callback for this purpose, which is used by the other targets.
rdar://problem/17277590
llvm-svn: 211095
There's probably no acatual change in behaviour here, just updating
the LowerFP_TO_INT function to be more similar to the reverse
implementation and updating costs to current CodeGen.
llvm-svn: 210985
This patch is to move GlobalMerge pass from Transform/Scalar
to CodeGen, because GlobalMerge depends on TargetMachine.
In the mean time, the macro INITIALIZE_TM_PASS is also moved
to CodeGen/Passes.h. With this fix we can avoid making
libScalarOpts depend on libCodeGen.
llvm-svn: 210951
This commit adds a weak variant of the cmpxchg operation, as described
in C++11. A cmpxchg instruction with this modifier is permitted to
fail to store, even if the comparison indicated it should.
As a result, cmpxchg instructions must return a flag indicating
success in addition to their original iN value loaded. Thus, for
uniformity *all* cmpxchg instructions now return "{ iN, i1 }". The
second flag is 1 when the store succeeded.
At the DAG level, a new ATOMIC_CMP_SWAP_WITH_SUCCESS node has been
added as the natural representation for the new cmpxchg instructions.
It is a strong cmpxchg.
By default this gets Expanded to the existing ATOMIC_CMP_SWAP during
Legalization, so existing backends should see no change in behaviour.
If they wish to deal with the enhanced node instead, they can call
setOperationAction on it. Beware: as a node with 2 results, it cannot
be selected from TableGen.
Currently, no use is made of the extra information provided in this
patch. Test updates are almost entirely adapting the input IR to the
new scheme.
Summary for out of tree users:
------------------------------
+ Legacy Bitcode files are upgraded during read.
+ Legacy assembly IR files will be invalid.
+ Front-ends must adapt to different type for "cmpxchg".
+ Backends should be unaffected by default.
llvm-svn: 210903
This commit is to improve global merge pass and support global symbol merge.
The global symbol merge is not enabled by default. For aarch64, we need some
more back-end fix to make it really benifit ADRP CSE.
llvm-svn: 210640
As Ana Pazos pointed out, these have to be restored to their incoming values
before a function returns; i.e. before the tail call. So they can't be used
correctly as the destination register.
llvm-svn: 210525
Previously we were abandonning the attempt, leading to some combination of
extra work (when selection of a load/store fails completely) and inferior code
(when this leads to a real memcpy call instead of inlining).
rdar://problem/17187463
llvm-svn: 210520
We were hitting an assert if FastISel couldn't create the load or store we
requested. Currently this happens for large frame-local addresses, though
CodeGen could be improved there.
rdar://problem/17187463
llvm-svn: 210519
The tests check that the following transform happens:
(ldr|str) X, [x20]
...
sub x20, x20, #16
->
(ldr|str) X, [x20], #-16
with X being either w0, x0, s0, d0 or q0.
llvm-svn: 210113
This means the output of LowerFormalArguments returns a lowered
SDValue with the correct type (expected in SelectionDAGBuilder).
Without this, an assertion under a DEBUG macro triggers when those
types are passed on the stack.
llvm-svn: 210102
The C and C++ semantics for compare_exchange require it to return a bool
indicating success. This gets mapped to LLVM IR which follows each cmpxchg with
an icmp of the value loaded against the desired value.
When lowered to ldxr/stxr loops, this extra comparison is redundant: its
results are implicit in the control-flow of the function.
This commit makes two changes: it replaces that icmp with appropriate PHI
nodes, and then makes sure earlyCSE is called after expansion to actually make
use of the opportunities revealed.
I've also added -{arm,aarch64}-enable-atomic-tidy options, so that
existing fragile tests aren't perturbed too much by the change. Many
of them either rely on undef/unreachable too pervasively to be
restored to something well-defined (particularly while making sure
they test the same obscure assert from many years ago), or depend on a
particular CFG shape, which is disrupted by SimplifyCFG.
rdar://problem/16227836
llvm-svn: 209883
This reverts r208640 (I've just XFAILed the test) because it broke ppc64/Linux
self-hosting. Because nearly every regression test triggers a segfault, I hope
this will be easy to fix.
llvm-svn: 209747
Add regression tests for the following transformation:
str X, [x20]
...
add x20, x20, #32
->
str X, [x20], #32
with X being either w0, x0, s0, d0 or q0.
llvm-svn: 209715
Add regression tests for the following transformation:
ldr X, [x20]
...
add x20, x20, #32
->
ldr X, [x20], #32
with X being either w0, x0, s0, d0 or q0.
llvm-svn: 209711
This commit is debatable. There are two possible approaches, neither
of which is really satisfactory:
1. Use "@foo(i1 zeroext)" to mean an extension to 32-bits on Darwin,
and 8 bits otherwise.
2. Redefine "@foo(i1)" to mean that the i1 is extended by the caller
to 8 bits. This goes against the spirit of "zeroext" I think, but
it's a bit of a vague construct anyway (by definition you're going
to extend to the amount required by the ABI, that's why it's the
ABI!).
This implements option 2. The DAG machinery really isn't setup for the
first (there's a fairly strong assumption that "zeroext" goes to at
least the smallest register size), and even if it was the resulting
DAG looks like it would be inferior in many cases.
Theoretically we could add AssertZext nodes in the consumers of
ABI-passed values too now, but this actually seems to make the code
worse in practice by making truncation proceed in two steps. The code
produced is equally valid if we continue to assume only the low bit is
defined.
Should fix PR19850
llvm-svn: 209637
We can eliminate the custom C++ code in favour of some TableGen to
check the same things. Functionality should be identical, except for a
buffer overrun that was present in the C++ code and meant webkit
failed if any small argument needed to be passed on the stack.
llvm-svn: 209636
Add tests for the following transform:
str X, [x0, #32]
...
add x0, x0, #32
->
str X, [x0, #32]!
with X being either w1, x1, s0, d0 or q0.
llvm-svn: 209627
We have a couple of regression tests for load/store pairing, but (to my knowledge) there are no regression tests for the load/store + add/sub folding.
As a first step towards increased test coverage of this area, this commit adds a test for one instance of a load + add to pre-indexed load transformation.
llvm-svn: 209618
This commit starts with a "git mv ARM64 AArch64" and continues out
from there, renaming the C++ classes, intrinsics, and other
target-local objects for consistency.
"ARM64" test directories are also moved, and tests that began their
life in ARM64 use an arm64 triple, those from AArch64 use an aarch64
triple. Both should be equivalent though.
This finishes the AArch64 merge, and everyone should feel free to
continue committing as normal now.
llvm-svn: 209577
I'm doing this in two phases for a better "git blame" record. This
commit removes the previous AArch64 backend and redirects all
functionality to ARM64. It also deduplicates test-lines and removes
orphaned AArch64 tests.
The next step will be "git mv ARM64 AArch64" and rewire most of the
tests.
Hopefully LLVM is still functional, though it would be even better if
no-one ever had to care because the rename happens straight
afterwards.
llvm-svn: 209576
This reverts commit r208934.
The patch depends on aliases to GEPs with non zero offsets. That is not
supported and fairly broken.
The good news is that GlobalAlias is being redesigned and will have support
for offsets, so this patch should be a nice match for it.
llvm-svn: 208978
TableGen has a fairly dubious heuristic to decide whether an alias should be
printed: does the alias have lest operands than the real instruction. This is
bad enough (particularly with no way to override it), but it should at least be
calculated consistently for both strings.
This patch implements that logic: first get the *correct* string for the
variant, in the same way as the Matcher, without guessing; then count the
number of whitespace chars.
There are basically 4 changes this brings about after the previous
commits; all of these appear to be good, so I have changed the tests:
+ ARM64: we print "neg X, Y" instead of "sub X, xzr, Y".
+ ARM64: we skip implicit "uxtx" and "uxtw" modifiers.
+ Sparc: we print "mov A, B" instead of "or %g0, A, B".
+ Sparc: we print "fcmpX A, B" instead of "fcmpX %fcc0, A, B"
llvm-svn: 208969
This commit implements two command line switches -global-merge-on-external
and -global-merge-aligned, and both of them are false by default, so this
optimization is disabled by default for all targets.
For ARM64, some back-end behaviors need to be tuned to get this optimization
further enabled.
llvm-svn: 208934
In all cases, if a "mov" alias exists, it is the canonical form of the
instruction. Now that TableGen can support aliases containing syntax variants,
we can enable them and improve the quality of the asm output.
llvm-svn: 208874
When performing a scalar comparison that feeds into a vector select,
it's actually better to do the comparison on the vector side: the
scalar route would be "CMP -> CSEL -> DUP", the vector is "CM -> DUP"
since the vector comparisons are all mask based.
llvm-svn: 208210
This completes the port of r204814 (cpirker "AArch64_BE function argument
passing for ARM ABI") from AArch64 to ARM64, and fixes a bunch of issues
found during later development along the way. The biggest of these was
that the alignment fixup logic wasn't replicated into all the places it
should have been.
llvm-svn: 208192
This patch implements the infrastructure to use named register constructs in
programs that need access to specific registers (bare metal, kernels, etc).
So far, only the stack pointer is supported as a technology preview, but as it
is, the intrinsic can already support all non-allocatable registers from any
architecture.
llvm-svn: 208104
An alias has the address of what it points to, so it also has the same
alignment.
This allows a few optimizations to see past aliases for free.
llvm-svn: 208103
The canonical form of the BFM instruction is always one of the more explicit
extract or insert operations, which makes reading output much easier.
llvm-svn: 207752
On instructions using the NZCV register, a couple of conditions have dual
representations: HS/CS and LO/CC (meaning unsigned-higher-or-same/carry-set and
unsigned-lower/carry-clear). The first of these is more descriptive in most
circumstances, so we should print it.
llvm-svn: 207644
Since these are mostly used in "lsl #16", "lsl #32", "lsl #48" combinations to
piece together an immediate in 16-bit chunks, hex is probably the most
appropriate format.
llvm-svn: 207635
Since these instructions only accept a 12-bit immediate, possibly shifted left
by 12, the canonical syntax used by the architecture reference manual is "#N {,
lsl #12 }". We should accept an immediate that has already been shifted, (e.g.
Also, print a comment giving the full addend since it can be helpful.
llvm-svn: 207633
This patch is a supplement of implementing predicate of FP, enabling aarch64 backend
no-fp tests on arm64 target for verification. During this, one bug is exposed and
fixed by this patch.
llvm-svn: 207215
This matches ARM64 behaviour, which I think is clearer. It also puts all the
churn from that difference into one easily ignored commit.
llvm-svn: 207116
ARM64 was not producing pure BFI instructions for bitfield insertion
operations, unlike AArch64. The approach had to be a little different (in
ISelDAGToDAG rather than ISelLowering), and the outcomes aren't identical but
hopefully this gives it similar power.
This should address PR19424.
llvm-svn: 207102
Code mostly copied from AArch64, just tidied up a trifle and plumbed
into the ARM64 way of doing things.
This also enables the AArch64 tests which inspired the previous
untested commits.
llvm-svn: 206574
ARM64 was scalarizing some vector comparisons which don't quite map to
AArch64's compare and mask instructions. AArch64's approach of sacrificing a
little efficiency to emulate them with the limited set available was better, so
I ported it across.
More "inspired by" than copy/paste since the backend's internal expectations
were a bit different, but the tests were invaluable.
llvm-svn: 206570
I enhanced it a little in the process. The decision shouldn't really be beased
on whether a BUILD_VECTOR is a splat: any set of constants will do the job
provided they're related in the correct way.
Also, the BUILD_VECTOR could be any operand of the incoming AND nodes, so it's
best to check for all 4 possibilities rather than assuming it'll be the RHS.
llvm-svn: 206569
It's not actually used to handle C or C++ ABI rules on ARM64, but could well be
emitted by other language front-ends, so it's as well to have a sensible
implementation.
llvm-svn: 206568
These ones used completely different sets of intrinsics, so the only way to do
it is create a separate ARM64 copy and change them all.
Other than that, CodeGen was straightforward, no deficiencies detected here.
llvm-svn: 206392
The most important part here is that we should actuall emit the stubs we refer
to in the exception table, but as a side issue this uses more sensible & GCC
compatible representations for some of the bits of information.
llvm-svn: 206380
If we know that a particular 64-bit constant has all high bits zero, then we
can rely on the fact that 32-bit ARM64 instructions automatically zero out the
high bits of an x-register. This gives the expansion logic less constraints to
satisfy and so sometimes allows it to pick better sequences.
Came up while porting test/CodeGen/AArch64/movw-consts.ll: this will allow a
32-bit MOVN to be used in @test8 soon.
llvm-svn: 206379
This particular DAG combine is designed to kick in when both ConstantFPs will
end up being loaded via a litpool, however those nodes have a semi-legal
status, dictated by isFPImmLegal so in some cases there wouldn't have been a
litpool in the first place. Don't try to be clever in those circumstances.
Picked up while merging some AArch64 tests.
llvm-svn: 206365
Sometimes we need emit the bits that would actually be a MOVN when producing a
relocated MOVZ instruction (don't ask). But not always, a check which ARM64 got
wrong until now.
llvm-svn: 206289
Code is mostly copied directly across, with a slight extension of the
ISelDAGToDAG function so that it can cope with the floating-point constants
being behind a litpool.
llvm-svn: 206285
