A global variable without an explicit alignment specified should be assumed to
be ABI-aligned according to its type, like on other platforms. This allows us
to use better memory operations when accessing it.
rdar://18533701
llvm-svn: 223180
This frequently leads to cases like:
ldr xD, [xN, :lo12:var]
add xA, xN, :lo12:var
ldr xD, [xA, #8]
where the ADD would have been needed anyway, and the two distinct addressing
modes can prevent the formation of an ldp. Because of how we handle ADRP
(aggressively forming an ADRP/ADD pseudo-inst at ISel time), this pattern also
results in duplicated ADRP instructions (one on its own to cover the ldr, and
one combined with the add).
llvm-svn: 223172
Reduce the number of nops emitted for stackmap shadows on AArch64 by counting
non-stackmap instructions up to the next branch target towards the requested
shadow.
<rdar://problem/14959522>
llvm-svn: 223156
Go through implicit defs of CSMI and MI, and clear the kill flags on
their uses in all the instructions between CSMI and MI.
We might have made some of the kill flags redundant, consider:
subs ... %NZCV<imp-def> <- CSMI
csinc ... %NZCV<imp-use,kill> <- this kill flag isn't valid anymore
subs ... %NZCV<imp-def> <- MI, to be eliminated
csinc ... %NZCV<imp-use,kill>
Since we eliminated MI, and reused a register imp-def'd by CSMI
(here %NZCV), that register, if it was killed before MI, should have
that kill flag removed, because it's lifetime was extended.
Also, add an exhaustive testcase for the motivating example.
Reviewed by: Juergen Ributzka <juergen@apple.com>
llvm-svn: 223133
The blocking code originated in ARM, which is more aggressive about casting
types to a canonical representative before doing anything else, so I missed out
most vector HFAs and broke the ABI. This should fix it.
llvm-svn: 223126
r208210 introduced an optimization that improves the vector select
codegen by doing the setcc on vectors directly.
This is a problem they the setcc operands are i1s, because the
optimization would create vectors of i1, which aren't legal.
Part of PR21549.
Differential Revision: http://reviews.llvm.org/D6308
llvm-svn: 223075
r213378 improved f16 bitcasts, so that they go directly through subregs,
instead of through the stack. That code now causes an assertion failure
for bitcasts from other 16-bits types (most importantly v2i8).
Correct that by doing the custom lowering for i16 bitcasts only when the
input is an f16.
Part of PR21549.
Differential Revision: http://reviews.llvm.org/D6307
llvm-svn: 223074
The MachineVerifier used to check that there was always exactly one
unconditional branch to a non-landingpad (normal) successor.
If that normal successor to an invoke BB is unreachable, it seems
reasonable to only have one successor, the landing pad.
On targets other than AArch64 (and on AArch64 with a different testcase),
the branch folder turns the branch to the landing pad into a fallthrough.
The MachineVerifier, which relies on AnalyzeBranch, is unable to check
the condition, and doesn't complain. However, it does in this specific
testcase, where the branch to the landing pad remained.
Make the MachineVerifier accept it.
llvm-svn: 223059
The AAPCS treats small structs and homogeneous floating (or vector) aggregates
specially, and guarantees they either get passed as a contiguous block of
registers, or prevent any future use of those registers and get passed on the
stack.
This concept can fit quite neatly into LLVM's own type system, mapping an HFA
to [N x float] and so on, and small structs to [N x i64]. Doing so allows
front-ends to emit AAPCS compliant code without having to duplicate the
register counting logic.
llvm-svn: 222903
This mostly entails adding relocations, however there are a couple of
changes to existing relocations:
1. R_AARCH64_NONE is defined to be zero rather than 256
R_AARCH64_NONE has been defined to be zero for a long time elsewhere
e.g. binutils and glibc since the submission of the AArch64 port in
2012 so this is required for compatibility.
2. R_AARCH64_TLSDESC_ADR_PAGE renamed to R_AARCH64_TLSDESC_ADR_PAGE21
I don't think there is any way for relocation names to leak out of LLVM
so this should not break anything.
Tested with check-all with no regressions.
llvm-svn: 222821
The pattern matching failed to recognize all instances of "-1", because when
comparing against "-1" we didn't use an APInt of the same bitwidth.
This commit fixes this and also adds inverse versions of the conditon to catch
more cases.
llvm-svn: 222722
E.g., ( a / D; b / D ) -> ( recip = 1.0 / D; a * recip; b * recip)
A hook is added to allow the target to control whether it needs to do such combine.
Reviewed in http://reviews.llvm.org/D6334
llvm-svn: 222510
SeparateConstOffsetFromGEP can gives more optimizaiton opportunities related to GEPs, which benefits EarlyCSE
and LICM. By enabling these passes we can have better address calculations and generate a better addressing
mode. Some SPEC 2006 benchmarks (astar, gobmk, namd) have obvious improvements on Cortex-A57.
Reviewed in http://reviews.llvm.org/D5864.
llvm-svn: 222331
shift-right for booleans (i1).
Arithmetic shift-right immediate with sign-/zero-extensions also works for
boolean values. Update the assert and the test cases to reflect that fact.
llvm-svn: 222272
shift-right for booleans (i1).
Logical shift-right immediate with sign-/zero-extensions also works for boolean
values. Update the assert and the test cases to reflect that fact.
llvm-svn: 222270
Shifts also perform sign-/zero-extends to larger types, which requires us to emit
an integer extend instead of a simple COPY.
Related to PR21594.
llvm-svn: 222257
This change emits a COPY for a shift-immediate with a "zero" shift value.
This fixes PR21594 where we emitted a shift instruction with an incorrect
immediate operand.
llvm-svn: 222247
The generic FastISel code would bail, because it can't emit a sign-extend for
AArch64. This copies the code over and uses AArch64 specific emit functions.
This is not ideal and 'computeAddress' should handles this, so it can fold the
address computation into the memory operation.
I plan to clean up 'computeAddress' anyways, so I will add that in a future
commit.
Related to rdar://problem/18962471.
llvm-svn: 221923
This folds the compare emission into the select emission when possible, so we
can directly use the flags and don't have to emit a separate compare.
Related to rdar://problem/18960150.
llvm-svn: 221847
In the case we optimize an integer extend away and replace it directly with the
source register, we also have to clear all kill flags at all its uses.
This is necessary, because the orignal IR instruction might be trivially dead,
but we replaced it with a nop at MI level.
llvm-svn: 221628
Reversing a CB* instruction used to drop the flags on the condition. On the
included testcase, this lead to a read from an undefined vreg.
Using addOperand keeps the flags, here <undef>.
Differential Revision: http://reviews.llvm.org/D6159
llvm-svn: 221507
While fixing up the register classes in the machine combiner in a previous
commit I missed one.
This fixes the last one and adds a test case.
llvm-svn: 221308
Registers are not all equal. Some are not allocatable (infinite cost),
some have to be preserved but can be used, and some others are just free
to use.
Ensure there is a cost hierarchy reflecting this fact, so that the
allocator will favor scratch registers over callee-saved registers.
llvm-svn: 221293
Some literals in the AArch64 backend had 15 'f's rather than 16, causing
comparisons with a constant 0xffffffffffffffff to be miscompiled.
llvm-svn: 221157
r212242 introduced a legalizer hook, originally to let AArch64 widen
v1i{32,16,8} rather than scalarize, because the legalizer expected, when
scalarizing the result of a conversion operation, to already have
scalarized the operands. On AArch64, v1i64 is legal, so that commit
ensured operations such as v1i32 = trunc v1i64 wouldn't assert.
It did that by choosing to widen v1 types whenever possible. However,
v1i1 types, for which there's no legal widened type, would still trigger
the assert.
This commit fixes that, by only scalarizing a trunc's result when the
operand has already been scalarized, and introducing an extract_elt
otherwise.
This is similar to r205625.
Fixes PR20777.
llvm-svn: 220937
Earlier this summer I fixed an issue where we were incorrectly combining
multiple loads that had different constraints such alignment, invariance,
temporality, etc. Apparently in one case I made copt paste error and swapped
alignment and invariance.
Tests included.
rdar://18816719
llvm-svn: 220933
Benchmarks have shown that it's harmless to the performance there, and having a
unified set of passes between the two cores where possible helps big.LITTLE
deployment.
Patch by Z. Zheng.
llvm-svn: 220744
This is a minor change to use the immediate version when the operand is a null
value. This should get rid of an unnecessary 'mov' instruction in debug
builds and align the code more with the one generated by SelectionDAG.
This fixes rdar://problem/18785125.
llvm-svn: 220713
The pattern matching for a 'ConstantInt' value was too restrictive. Checking for
a 'Constant' with a bull value is sufficient for using an 'cbz/cbnz' instruction.
This fixes rdar://problem/18784732.
llvm-svn: 220709
This fixes a bug where the input register was not defined for the 'tbz/tbnz'
instruction. This happened, because we folded the 'and' instruction from a
different basic block.
This fixes rdar://problem/18784013.
llvm-svn: 220704
At higher optimization levels the LLVM IR may contain more complex patterns for
loads/stores from/to frame indices. The 'computeAddress' function wasn't able to
handle this and triggered an assertion.
This fix extends the possible addressing modes for frame indices.
This fixes rdar://problem/18783298.
llvm-svn: 220700
This fixes a miscompilation in the AArch64 fast-isel which was
triggered when a branch is based on an icmp with condition eq or ne,
and type i1, i8 or i16. The cbz instruction compares the whole 32-bit
register, so values with the bottom 1, 8 or 16 bits clear would cause
the wrong branch to be taken.
llvm-svn: 220553
This adds support for legalization of instructions of the form:
[fp_conv] <1 x i1> %op to <1 x double>
where fp_conv is one of fpto[us]i, [us]itofp. This used to assert
because they were simply missing from the vector operand scalarizer.
A similar problem arose in r190830, with trunc instead.
Fixes PR20778.
Differential Revision: http://reviews.llvm.org/D5810
llvm-svn: 220533
This enables targets to adapt their pass pipeline to the register
allocator in use. For example, with the AArch64 backend, using PBQP
with the cortex-a57, the FPLoadBalancing pass is no longer necessary.
llvm-svn: 220321
Every target we support has support for assembly that looks like
a = b - c
.long a
What is special about MachO is that the above combination suppresses the
production of a relocation.
With this change we avoid producing the intermediary labels when they don't
add any value.
llvm-svn: 220256
