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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213248 91177308-0d34-0410-b5e6-96231b3b80d8
This fixes an issue where a local value is defined before and used after an
inline asm call with side effects.
This fix simply flushes the local value map, which updates the insertion point
for the inline asm call to be above any previously defined local values.
This fixes <rdar://problem/17694203>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213203 91177308-0d34-0410-b5e6-96231b3b80d8
The coalescer is very aggressive at propagating constraints on the register classes, and the register allocator doesn’t know how to split sub-registers later to recover. This patch provides an escape valve for targets that encounter this problem to limit coalescing.
This patch also implements such for ARM to lower register pressure when using lots of large register classes. This works around PR18825.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213078 91177308-0d34-0410-b5e6-96231b3b80d8
This crash was pretty common while compiling Rust for iOS (armv7). Reason -
SjLj preparation step was lowering aggregate arguments as ExtractValue +
InsertValue. ExtractValue has assertion which checks that there is some data in
value, which is not true in case of empty (no fields) structures. Rust uses
them quite extensively so this patch uses a 'select true, %val, undef'
instruction to lower the argument.
Patch by Valerii Hiora.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212922 91177308-0d34-0410-b5e6-96231b3b80d8
This completes the handling for DLL import storage symbols when lowering
instructions. A DLL import storage symbol must have an additional load
performed prior to use. This is applicable to variables and functions.
This is particularly important for non-function symbols as it is possible to
handle function references by emitting a thunk which performs the translation
from the unprefixed __imp_ symbol to the proper symbol (although, this is a
non-optimal lowering). For a variable symbol, no such thunk can be
accommodated.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212431 91177308-0d34-0410-b5e6-96231b3b80d8
Adds support for __builtin_arm_isb. Also corrects DSB and ISB instructions
modelling by adding has-side-effects property.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212276 91177308-0d34-0410-b5e6-96231b3b80d8
Most of this is just tests that were silently succeeding in spite of
schema changes I made over a year ago. Cleaning them up as they lead to
failures in a change I'm working on/will come soon.
test/DebugInfo/2010-01-19-DbgScope.ll was removed as it tested miscoping
where a DebugLoc described a location not in the current function. The
test case doesn't describe why this is a valid situation and should be
supported, so I'm removing it and shortly going to commit changes that
make this firmly unsupported/assert-fail.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211628 91177308-0d34-0410-b5e6-96231b3b80d8
ARM v7M has ldrex/strex but not ldrexd/strexd. This means 32-bit
operations should work as normal, but 64-bit ones are almost certainly
doomed.
Patch by Phoebe Buckheister.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211042 91177308-0d34-0410-b5e6-96231b3b80d8
This also simplifies the IR we create slightly: instead of working out
where success & failure should go manually, it turns out we can just
always jump to a success/failure block created for the purpose. Later
phases will sort out the mess without much difficulty.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210917 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210903 91177308-0d34-0410-b5e6-96231b3b80d8
Windows on ARM uses COFF/PE which is intrinsically position independent. For
the case of 32-bit immediates, use a pair-wise relocation as otherwise we may
exceed the range of operators. This fixes a code generation crash when using
-Oz when targeting Windows on ARM.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210814 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210640 91177308-0d34-0410-b5e6-96231b3b80d8
The armv7-windows-itanium environment is nearly identical to the MSVC ABI. It
has a few divergences, mostly revolving around the use of the Itanium ABI for
C++. VLA support is one of the extensions that are amongst the set of the
extensions.
This adds support for proper VLA emission for this environment. This is
somewhat similar to the handling for __chkstk emission on X86 and the large
stack frame emission for ARM. The invocation style for chkstk is still
controlled via the -mcmodel flag to clang.
Make an explicit note that this is an extension.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210489 91177308-0d34-0410-b5e6-96231b3b80d8
COFF/PE, so the relocation model is never static. Loosen the assertion
accordingly. The relocation can still be emitted properly, as it will be
converted to an IMAGE_REL_ARM_ADDR32 which will be resolved by the loader
taking the base relocation into account. This is necessary to permit the
emission of long calls which can be controlled via the -mlong-calls option in
the driver.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210399 91177308-0d34-0410-b5e6-96231b3b80d8
It includes a pass that rewrites all indirect calls to jumptable functions to pass through these tables.
This also adds backend support for generating the jump-instruction tables on ARM and X86.
Note that since the jumptable attribute creates a second function pointer for a
function, any function marked with jumptable must also be marked with unnamed_addr.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210280 91177308-0d34-0410-b5e6-96231b3b80d8
This patch changes GlobalAlias to point to an arbitrary ConstantExpr and it is
up to MC (or the system assembler) to decide if that expression is valid or not.
This reduces our ability to diagnose invalid uses and how early we can spot
them, but it also lets us do things like
@test5 = alias inttoptr(i32 sub (i32 ptrtoint (i32* @test2 to i32),
i32 ptrtoint (i32* @bar to i32)) to i32*)
An important implication of this patch is that the notion of aliased global
doesn't exist any more. The alias has to encode the information needed to
access it in its metadata (linkage, visibility, type, etc).
Another consequence to notice is that getSection has to return a "const char *".
It could return a NullTerminatedStringRef if there was such a thing, but when
that was proposed the decision was to just uses "const char*" for that.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210062 91177308-0d34-0410-b5e6-96231b3b80d8
Unordered is strictly weaker than monotonic, so if the latter doesn't have any
barriers then the former certainly shouldn't.
rdar://problem/16548260
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209901 91177308-0d34-0410-b5e6-96231b3b80d8
Darwin prologues save their GPRs in two stages: a narrow push of r0-r7 & lr,
followed by a wide push of the remaining registers if there are any. AAPCS uses
a single push.w instruction.
It turns out that, on average, enough registers get pushed that code is smaller
in the AAPCS prologue, which is a nice property for M-class programmers. They
also have other options available for back-traces, so can hopefully deal with
the fact that FP & LR aren't adjacent in memory.
rdar://problem/15909583
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209895 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209883 91177308-0d34-0410-b5e6-96231b3b80d8
Cortex-M4 only has single-precision floating point support, so any LLVM
"double" type will have been split into 2 i32s by now. Fortunately, the
consecutive-register framework turns out to be precisely what's needed to
reconstruct the double and follow AAPCS-VFP correctly!
rdar://problem/17012966
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209650 91177308-0d34-0410-b5e6-96231b3b80d8
This intrinsic permits the emission of platform specific undefined sequences.
ARM has reserved the 0xde opcode which takes a single integer parameter (ignored
by the CPU). This permits the operating system to implement custom behaviour on
this trap. The llvm.arm.undefined intrinsic is meant to provide a means for
generating the target specific behaviour from the frontend. This is
particularly useful for Windows on ARM which has made use of a series of these
special opcodes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209390 91177308-0d34-0410-b5e6-96231b3b80d8
Although the previous code would construct a bundle and add the correct elements
to it, it would not finalise the bundle. This resulted in the InternalRead
markers not being added to the MachineOperands nor, more importantly, the
externally visible defs to the bundle itself. So, although the bundle was not
exposing the def, the generated code would be correct because there was no
optimisations being performed. When optimisations were enabled, the post
register allocator would kick in, and the hazard recognizer would reorder
operations around the load which would define the value being operated upon.
Rather than manually constructing the bundle, simply construct and finalise the
bundle via the finaliseBundle call after both MIs have been emitted. This
improves the code generation with optimisations where IMAGE_REL_ARM_MOV32T
relocations are emitted.
The changes to the other tests are the result of the bundle generation
preventing the scheduler from hoisting the moves across the loads. The net
effect of the generated code is equivalent, but, is much more identical to what
is actually being lowered.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209267 91177308-0d34-0410-b5e6-96231b3b80d8
- On ARM/ARM64 we get a vrev because the shuffle matching code is really smart. We still unroll anything that's not v4i32 though.
- On X86 we get a pshufb with SSSE3. Required more cleverness in isShuffleMaskLegal.
- On PPC we get a vperm for v8i16 and v4i32. v2i64 is unrolled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209123 91177308-0d34-0410-b5e6-96231b3b80d8
Windows on ARM uses R11 for the frame pointer even though the environment is a
pure Thumb-2, thumb-only environment. Replicate this behaviour to improve
Windows ABI compatibility. This register is used for fast stack walking, and
thus is part of the Windows ABI.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209085 91177308-0d34-0410-b5e6-96231b3b80d8
WoA uses COFF, not ELF. ARMISelLowering::createTLOF would previously return ELF
for any non-MachO platform. This was a missed site when the original change for
target format support for Windows on ARM was done.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209057 91177308-0d34-0410-b5e6-96231b3b80d8
This patch changes the design of GlobalAlias so that it doesn't take a
ConstantExpr anymore. It now points directly to a GlobalObject, but its type is
independent of the aliasee type.
To avoid changing all alias related tests in this patches, I kept the common
syntax
@foo = alias i32* @bar
to mean the same as now. The cases that used to use cast now use the more
general syntax
@foo = alias i16, i32* @bar.
Note that GlobalAlias now behaves a bit more like GlobalVariable. We
know that its type is always a pointer, so we omit the '*'.
For the bitcode, a nice surprise is that we were writing both identical types
already, so the format change is minimal. Auto upgrade is handled by looking
through the casts and no new fields are needed for now. New bitcode will
simply have different types for Alias and Aliasee.
One last interesting point in the patch is that replaceAllUsesWith becomes
smart enough to avoid putting a ConstantExpr in the aliasee. This seems better
than checking and updating every caller.
A followup patch will delete getAliasedGlobal now that it is redundant. Another
patch will add support for an explicit offset.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209007 91177308-0d34-0410-b5e6-96231b3b80d8
DIBuilder maintains this invariant and the current DwarfDebug code could
end up doing weird things if it contained declarations (such as putting
the definition DIE inside a CU that contained the declaration - this
doesn't seem like a good idea, so rather than adding logic to handle
this case we'll just ban in for now & cross that bridge if we come to
it later).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209004 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208978 91177308-0d34-0410-b5e6-96231b3b80d8
Add some Windows on ARM specific library calls. These are provided by msvcrt,
and can be used to perform integer to floating-point conversions (and
vice-versa) mirroring similar functions in the RTABI.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208949 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208934 91177308-0d34-0410-b5e6-96231b3b80d8
If the function has the landingpad instruction, then the
handlerdata should be emitted even if the function has
nouwnind attribute. Otherwise, following code will not
work:
void test1() noexcept {
try {
throw_exception();
} catch (...) {
log_unexpected_exception();
}
}
Since the cantunwind was incorrectly emitted and the
LSDA is not available.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208791 91177308-0d34-0410-b5e6-96231b3b80d8
The commit r208166 will cause some regression on ARM EHABI.
This fix has been committed in r208715, and an assertion failure
test case has been committed in r208770.
This commit further extends the unittest so that the actual
value in the handlerdata will be checked.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208790 91177308-0d34-0410-b5e6-96231b3b80d8
This commit was already commited as revision rL208689 and discussd in
phabricator revision D3704.
But the test file was crashing on OS X and windows.
I fixed the test file in the same way as in rL208340.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208711 91177308-0d34-0410-b5e6-96231b3b80d8
Windows on ARM only supports thumb mode execution, so we have to
explicitly pick some non-Windows OS to test ARM mode codegen.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208638 91177308-0d34-0410-b5e6-96231b3b80d8
The current patterns for REV16 misses mostn __builtin_bswap16() due to
legalization promoting the operands to from load/stores toi32s and then
truncing/extending them. This patch adds new patterns that catch the resultant
DAGs and codegens them to rev16 instructions. Tests included.
rdar://15353652
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208620 91177308-0d34-0410-b5e6-96231b3b80d8
Windows on ARM only supports thumb mode execution, so we have to
explicitly pick some non-Windows OS to test ARM mode codegen.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208448 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds support to ARM for custom lowering of the
llvm.{u|s}add.with.overflow.i32 intrinsics for i32/i64. This is particularly useful
for handling idiomatic saturating math functions as generated by
InstCombineCompare.
Test cases included.
rdar://14853450
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208435 91177308-0d34-0410-b5e6-96231b3b80d8
When using the ARM AAPCS, HFAs (Homogeneous Floating-point Aggregates) must
be passed in a block of consecutive floating-point registers, or on the stack.
This means that unused floating-point registers cannot be back-filled with
part of an HFA, however this can currently happen. This patch, along with the
corresponding clang patch (http://reviews.llvm.org/D3083) prevents this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208413 91177308-0d34-0410-b5e6-96231b3b80d8
Handle lowering of global addresses for PIC mode compilation on Windows. Always
use the movw/movt load to load the address as Windows on ARM requires ARMv7+ and
is a pure Thumb environment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208385 91177308-0d34-0410-b5e6-96231b3b80d8
This tightens up r208351 to ensure that a store is fed with the
correct value.
Thanks to Quentin Colombet for spotting this!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208368 91177308-0d34-0410-b5e6-96231b3b80d8
When building on Windows, the default target is Windows. Windows on ARM does
not support ARM mode compilation, resulting in test failures. Simply specify a
triple to ensure that we are testing the correct behaviour.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208340 91177308-0d34-0410-b5e6-96231b3b80d8
The ARM::BLX instruction is an ARM mode instruction. The Windows on ARM target
is limited to Thumb instructions. Correctly use the thumb mode tBLXr
instruction. This would manifest as an errant write into the object file as the
instruction is 4-bytes in length rather than 2. The result would be a corrupted
object file that would eventually result in an executable that would crash at
runtime.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208152 91177308-0d34-0410-b5e6-96231b3b80d8
remove it from the list of unspilled registers. Otherwise the following
attempt to keep the stack aligned by picking an extra GPR register to
spill will not work as it picks up r11.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208129 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208104 91177308-0d34-0410-b5e6-96231b3b80d8
Windows on ARM does not conform to AEABI. However, memset would be emitted
using the AEABI signature, resulting in inverted parameters. Handle this
special case appropriately.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207943 91177308-0d34-0410-b5e6-96231b3b80d8
This introduces the stack lowering emission of the stack probe function for
Windows on ARM. The stack on Windows on ARM is a dynamically paged stack where
any page allocation which crosses a page boundary of the following guard page
will cause a page fault. This page fault must be handled by the kernel to
ensure that the page is faulted in. If this does not occur and a write access
any memory beyond that, the page fault will go unserviced, resulting in an
abnormal program termination.
The watermark for the stack probe appears to be at 4080 bytes (for
accommodating the stack guard canaries and stack alignment) when SSP is
enabled. Otherwise, the stack probe is emitted on the page size boundary of
4096 bytes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207615 91177308-0d34-0410-b5e6-96231b3b80d8
IMAGE_REL_ARM_MOV32T relocations require that the movw/movt pair-wise
relocation is not split up and reordered. When expanding the mov32imm
pseudo-instruction, create a bundle if the machine operand is referencing an
address. This helps ensure that the relocatable address load is not reordered
by subsequent passes.
Unfortunately, this only partially handles the case as the Constant Island Pass
occurs after the instructions are unbundled and does not properly handle
bundles. That is a more fundamental issue with the pass itself and beyond the
scope of this change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207608 91177308-0d34-0410-b5e6-96231b3b80d8
This intrinsic is no longer needed with the new @llvm.arm.hint(i32) intrinsic
which provides a generic, extensible manner for adding hint instructions. This
functionality can now be represented as @llvm.arm.hint(i32 5).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207246 91177308-0d34-0410-b5e6-96231b3b80d8
Introduce the llvm.arm.hint(i32) intrinsic that can be used to inject hints into
the instruction stream. This is particularly useful for generating IR from a
compiler where the user may inject an intrinsic (e.g. __yield). These are then
pattern substituted into the correct instruction which already existed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207242 91177308-0d34-0410-b5e6-96231b3b80d8
The 'CHECK: add' line was occasionally matching against the filename,
breaking the subsequent CHECK-NOT. Also use CHECK-LABEL.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206936 91177308-0d34-0410-b5e6-96231b3b80d8
The point of these calls is to allow Thumb-1 code to make use of the VFP unit
to perform its operations. This is not desirable with -msoft-float, since most
of the reasons you'd want that apply equally to the runtime library.
rdar://problem/13766161
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206874 91177308-0d34-0410-b5e6-96231b3b80d8
handles Intrinsic::trap if TargetOptions::TrapFuncName is set.
This fixes a bug in which the trap function was not taken into consideration
when a program was compiled without optimization (at -O0).
<rdar://problem/16291933>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206323 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, BranchProbabilityInfo::calcLoopBranchHeuristics would determine the weights of basic blocks inside loops even when it didn't have enough information to estimate the branch probabilities correctly. This patch fixes the function to exit early if it doesn't see any exit edges or back edges and let the later heuristics determine the weights.
This fixes PR18705 and <rdar://problem/15991090>.
Differential Revision: http://reviews.llvm.org/D3363
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206194 91177308-0d34-0410-b5e6-96231b3b80d8
The current memory-instruction optimization logic in CGP, which sinks parts of
the address computation that can be adsorbed by the addressing mode, does this
by explicitly converting the relevant part of the address computation into
IR-level integer operations (making use of ptrtoint and inttoptr). For most
targets this is currently not a problem, but for targets wishing to make use of
IR-level aliasing analysis during CodeGen, the use of ptrtoint/inttoptr is a
problem for two reasons:
1. BasicAA becomes less powerful in the face of the ptrtoint/inttoptr
2. In cases where type-punning was used, and BasicAA was used
to override TBAA, BasicAA may no longer do so. (this had forced us to disable
all use of TBAA in CodeGen; something which we can now enable again)
This (use of GEPs instead of ptrtoint/inttoptr) is not currently enabled by
default (except for those targets that use AA during CodeGen), and so aside
from some PowerPC subtargets and SystemZ, there should be no change in
behavior. We may be able to switch completely away from the ptrtoint/inttoptr
sinking on all targets, but further testing is required.
I've doubled-up on a number of existing tests that are sensitive to the
address sinking behavior (including some store-merging tests that are
sensitive to the order of the resulting ADD operations at the SDAG level).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206092 91177308-0d34-0410-b5e6-96231b3b80d8
This removes the -segmented-stacks command line flag in favor of a
per-function "split-stack" attribute.
Patch by Luqman Aden and Alex Crichton!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205997 91177308-0d34-0410-b5e6-96231b3b80d8
More updating of tests to be explicit about the target triple rather than
relying on the default target triple supporting ARM mode.
Indicate to lit that object emission is not yet available for Windows on ARM.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205545 91177308-0d34-0410-b5e6-96231b3b80d8
This changes the tests that were targeting ARM EABI to explicitly specify the
environment rather than relying on the default. This breaks with the new
Windows on ARM support when running the tests on Windows where the default
environment is no longer EABI.
Take the opportunity to avoid a pointless redirect (helps when trying to debug
with providing a command line invocation which can be copy and pasted) and
removing a few greps in favour of FileCheck.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205541 91177308-0d34-0410-b5e6-96231b3b80d8
Implementing this via ComputeMaskedBits has two advantages:
+ It actually works. DAGISel doesn't deal with the chains properly
in the previous pattern-based solution, so they never trigger.
+ The information can be used in other DAG combines, as well as the
trivial "get rid of truncs". For example if the trunc is in a
different basic block.
rdar://problem/16227836
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205540 91177308-0d34-0410-b5e6-96231b3b80d8
The terminal barrier of a cmpxchg expansion will be either Acquire or
SequentiallyConsistent. In either case it can be skipped if the
operation has Monotonic requirements on failure.
rdar://problem/15996804
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205535 91177308-0d34-0410-b5e6-96231b3b80d8
The previous situation where ATOMIC_LOAD_WHATEVER nodes were expanded
at MachineInstr emission time had grown to be extremely large and
involved, to account for the subtly different code needed for the
various flavours (8/16/32/64 bit, cmpxchg/add/minmax).
Moving this transformation into the IR clears up the code
substantially, and makes future optimisations much easier:
1. an atomicrmw followed by using the *new* value can be more
efficient. As an IR pass, simple CSE could handle this
efficiently.
2. Making use of cmpxchg success/failure orderings only has to be done
in one (simpler) place.
3. The common "cmpxchg; did we store?" idiom can be exposed to
optimisation.
I intend to gradually improve this situation within the ARM backend
and make sure there are no hidden issues before moving the code out
into CodeGen to be shared with (at least ARM64/AArch64, though I think
PPC & Mips could benefit too).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205525 91177308-0d34-0410-b5e6-96231b3b80d8
add operation since extract_vector_elt can perform an extend operation. Get the input lane
type from the vector on which we're performing the vpaddl operation on and extend or
truncate it to the output type of the original add node.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205523 91177308-0d34-0410-b5e6-96231b3b80d8
This changes the tests that were targeting ARM EABI to explicitly specify the
environment rather than relying on the default. This breaks with the new
Windows on ARM support when running the tests on Windows where the default
environment is no longer EABI.
Take the opportunity to avoid a pointless redirect (helps when trying to debug
with providing a command line invocation which can be copy and pasted) and
removing a few greps in favour of FileCheck.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205465 91177308-0d34-0410-b5e6-96231b3b80d8
Update the subtarget information for Windows on ARM. This enables using the MC
layer to target Windows on ARM.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205459 91177308-0d34-0410-b5e6-96231b3b80d8
ARM specific optimiztion, finding places in ARM machine code where 2 dmbs
follow one another, and eliminating one of them.
Patch by Reinoud Elhorst.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205409 91177308-0d34-0410-b5e6-96231b3b80d8
The Cyclone CPU is similar to swift for most LLVM purposes, but does have two
preferred instructions for zeroing a VFP register. This teaches LLVM about
them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205309 91177308-0d34-0410-b5e6-96231b3b80d8
This moves one case of raw text checking down into the MCStreamer
interfaces in the form of a virtual function, even if we ultimately end
up consolidating on the one-or-many line tables issue one day, this is
nicer in the interim. This just generally streamlines a bunch of use
cases into a common code path.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205287 91177308-0d34-0410-b5e6-96231b3b80d8
We've already got versions without the barriers, so this just adds IR-level
support for generating the new v8 ones.
rdar://problem/16227836
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204813 91177308-0d34-0410-b5e6-96231b3b80d8
Implementing the LLVM part of the call to __builtin___clear_cache
which translates into an intrinsic @llvm.clear_cache and is lowered
by each target, either to a call to __clear_cache or nothing at all
incase the caches are unified.
Updating LangRef and adding some tests for the implemented architectures.
Other archs will have to implement the method in case this builtin
has to be compiled for it, since the default behaviour is to bail
unimplemented.
A Clang patch is required for the builtin to be lowered into the
llvm intrinsic. This will be done next.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204802 91177308-0d34-0410-b5e6-96231b3b80d8
Sicne MBB->computeRegisterLivenes() returns Dead for sub regs like s0,
d0 is used in vpop instead of updating sp, which causes s0 dead before
its use.
This patch checks the liveness of each subreg to make sure the reg is
actually dead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204411 91177308-0d34-0410-b5e6-96231b3b80d8
These linkages were introduced some time ago, but it was never very
clear what exactly their semantics were or what they should be used
for. Some investigation found these uses:
* utf-16 strings in clang.
* non-unnamed_addr strings produced by the sanitizers.
It turns out they were just working around a more fundamental problem.
For some sections a MachO linker needs a symbol in order to split the
section into atoms, and llvm had no idea that was the case. I fixed
that in r201700 and it is now safe to use the private linkage. When
the object ends up in a section that requires symbols, llvm will use a
'l' prefix instead of a 'L' prefix and things just work.
With that, these linkages were already dead, but there was a potential
future user in the objc metadata information. I am still looking at
CGObjcMac.cpp, but at this point I am convinced that linker_private
and linker_private_weak are not what they need.
The objc uses are currently split in
* Regular symbols (no '\01' prefix). LLVM already directly provides
whatever semantics they need.
* Uses of a private name (start with "\01L" or "\01l") and private
linkage. We can drop the "\01L" and "\01l" prefixes as soon as llvm
agrees with clang on L being ok or not for a given section. I have two
patches in code review for this.
* Uses of private name and weak linkage.
The last case is the one that one could think would fit one of these
linkages. That is not the case. The semantics are
* the linker will merge these symbol by *name*.
* the linker will hide them in the final DSO.
Given that the merging is done by name, any of the private (or
internal) linkages would be a bad match. They allow llvm to rename the
symbols, and that is really not what we want. From the llvm point of
view, these objects should really be (linkonce|weak)(_odr)?.
For now, just keeping the "\01l" prefix is probably the best for these
symbols. If we one day want to have a more direct support in llvm,
IMHO what we should add is not a linkage, it is just a hidden_symbol
attribute. It would be applicable to multiple linkages. For example,
on weak it would produce the current behavior we have for objc
metadata. On internal, it would be equivalent to private (and we
should then remove private).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203866 91177308-0d34-0410-b5e6-96231b3b80d8
This option enables LowerInvoke's obsolete SJLJ EH support, but the
target used in this test (ARM Darwin) no longer uses the LowerInvoke
pass, so the option has no effect here. This target currently uses
the newer SjLjEHPrepare pass instead.
This cleanup will help with removing "-enable-correct-eh-support".
Differential Revision: http://llvm-reviews.chandlerc.com/D3064
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203810 91177308-0d34-0410-b5e6-96231b3b80d8
This is a follow-up to r203635. Saleem pointed out that since symbolic register
names are much easier to read, it would be good if we could turn them off only
when we really need to because we're using an external assembler.
Differential Revision: http://llvm-reviews.chandlerc.com/D3056
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203806 91177308-0d34-0410-b5e6-96231b3b80d8
When the list of VFP registers to be saved was non-contiguous (so multiple
vpush/vpop instructions were needed) these were being ordered oddly, as in:
vpush {d8, d9}
vpush {d11}
This led to the layout in memory being [d11, d8, d9] which is ugly and doesn't
match the CFI_INSTRUCTIONs we're generating either (so Dwarf info would be
broken).
This switches the order of vpush/vpop (in both prologue and epilogue,
obviously) so that the Dwarf locations are correct again.
rdar://problem/16264856
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203655 91177308-0d34-0410-b5e6-96231b3b80d8
Use the options in the ARMISelLowering to control whether tail calls are
optimised or not. Previously, this option was entirely ignored on the ARM
target and only honoured on x86.
This option is mostly useful in profiling scenarios. The default remains that
tail call optimisations will be applied.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203577 91177308-0d34-0410-b5e6-96231b3b80d8
This option is from 2010, designed to work around a linker issue on Darwin for
ARM. According to grosbach this is no longer an issue and this option can
safely be removed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203576 91177308-0d34-0410-b5e6-96231b3b80d8
Tail call optimisation was previously disabled on all targets other than
iOS5.0+. This enables the tail call optimisation on all Thumb 2 capable
platforms.
The test adjustments are to remove the IR hint "tail" to function invocation.
The tests were designed assuming that tail call optimisations would not kick in
which no longer holds true.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203575 91177308-0d34-0410-b5e6-96231b3b80d8
The syntax for "cmpxchg" should now look something like:
cmpxchg i32* %addr, i32 42, i32 3 acquire monotonic
where the second ordering argument gives the required semantics in the case
that no exchange takes place. It should be no stronger than the first ordering
constraint and cannot be either "release" or "acq_rel" (since no store will
have taken place).
rdar://problem/15996804
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203559 91177308-0d34-0410-b5e6-96231b3b80d8
The old system was fairly convoluted:
* A temporary label was created.
* A single PROLOG_LABEL was created with it.
* A few MCCFIInstructions were created with the same label.
The semantics were that the cfi instructions were mapped to the PROLOG_LABEL
via the temporary label. The output position was that of the PROLOG_LABEL.
The temporary label itself was used only for doing the mapping.
The new CFI_INSTRUCTION has a 1:1 mapping to MCCFIInstructions and points to
one by holding an index into the CFI instructions of this function.
I did consider removing MMI.getFrameInstructions completelly and having
CFI_INSTRUCTION own a MCCFIInstruction, but MCCFIInstructions have non
trivial constructors and destructors and are somewhat big, so the this setup
is probably better.
The net result is that we don't create temporary labels that are never used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203204 91177308-0d34-0410-b5e6-96231b3b80d8
scan the register file for sub- and super-registers.
No functionality change intended.
(Tests are updated because the comments in the assembler output are
different.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202416 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Fixes an issue where a test attempts to use -mcpu=cortex-a15 on non-ARM targets.
This triggers an assertion on MIPS since it doesn't know what ABI to use by default for
unrecognized processors.
Reviewers: rengolin
Reviewed By: rengolin
CC: llvm-commits, aemerson, rengolin
Differential Revision: http://llvm-reviews.chandlerc.com/D2876
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202256 91177308-0d34-0410-b5e6-96231b3b80d8
The function with uwtable attribute might be visited by the
stack unwinder, thus the link register should be considered
as clobbered after the execution of the branch and link
instruction (i.e. the definition of the machine instruction
can't be ignored) even when the callee function are marked
with noreturn.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202165 91177308-0d34-0410-b5e6-96231b3b80d8
NaCl's ARM ABI uses 16 byte stack alignment, so set that in
ARMSubtarget.cpp.
Using 16 byte alignment exposes an issue in code generation in which a
varargs function leaves a 4 byte gap between the values of r1-r3 saved
to the stack and the following arguments that were passed on the
stack. (Previously, this code only needed to support 4 byte and 8
byte alignment.)
With this issue, llc generated:
varargs_func:
sub sp, sp, #16
push {lr}
sub sp, sp, #12
add r0, sp, #16 // Should be 20
stm r0, {r1, r2, r3}
ldr r0, .LCPI0_0 // Address of va_list
add r1, sp, #16
str r1, [r0]
bl external_func
Fix the bug by checking for "Align > 4". Also simplify the code by
using OffsetToAlignment(), and update comments.
Differential Revision: http://llvm-reviews.chandlerc.com/D2677
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201497 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
AsmPrinter::EmitInlineAsm() will no longer use the EmitRawText() call for
targets with mature MC support. Such targets will always parse the inline
assembly (even when emitting assembly). Targets without mature MC support
continue to use EmitRawText() for assembly output.
The hasRawTextSupport() check in AsmPrinter::EmitInlineAsm() has been replaced
with MCAsmInfo::UseIntegratedAs which when true, causes the integrated assembler
to parse inline assembly (even when emitting assembly output). UseIntegratedAs
is set to true for targets that consider any failure to parse valid assembly
to be a bug. Target specific subclasses generally enable the integrated
assembler in their constructor. The default value can be overridden with
-no-integrated-as.
All tests that rely on inline assembly supporting invalid assembly (for example,
those that use mnemonics such as 'foo' or 'hello world') have been updated to
disable the integrated assembler.
Changes since review (and last commit attempt):
- Fixed test failures that were missed due to configuration of local build.
(fixes crash.ll and a couple others).
- Fixed tests that happened to pass because the local build was on X86
(should fix 2007-12-17-InvokeAsm.ll)
- mature-mc-support.ll's should no longer require all targets to be compiled.
(should fix ARM and PPC buildbots)
- Object output (-filetype=obj and similar) now forces the integrated assembler
to be enabled regardless of default setting or -no-integrated-as.
(should fix SystemZ buildbots)
Reviewers: rafael
Reviewed By: rafael
CC: llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D2686
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201333 91177308-0d34-0410-b5e6-96231b3b80d8
The front-end is now generating the generic @llvm.fabs for this
operation now, so the extra patterns are no longer needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201314 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
AsmPrinter::EmitInlineAsm() will no longer use the EmitRawText() call for targets with mature MC support. Such targets will always parse the inline assembly (even when emitting assembly). Targets without mature MC support continue to use EmitRawText() for assembly output.
The hasRawTextSupport() check in AsmPrinter::EmitInlineAsm() has been replaced with MCAsmInfo::UseIntegratedAs which when true, causes the integrated assembler to parse inline assembly (even when emitting assembly output). UseIntegratedAs is set to true for targets that consider any failure to parse valid assembly to be a bug. Target specific subclasses generally enable the integrated assembler in their constructor. The default value can be overridden with -no-integrated-as.
All tests that rely on inline assembly supporting invalid assembly (for example, those that use mnemonics such as 'foo' or 'hello world') have been updated to disable the integrated assembler.
Reviewers: rafael
Reviewed By: rafael
CC: llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D2686
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201237 91177308-0d34-0410-b5e6-96231b3b80d8
* CPRCs may be allocated to co-processor registers or the stack – they may never be allocated to core registers
* When a CPRC is allocated to the stack, all other VFP registers should be marked as unavailable
The difference is only noticeable in rare cases where there are a large number of floating point arguments (e.g.
7 doubles + additional float, double arguments). Although it's probably still better to avoid vmov as it can cause
stalls in some older ARM cores. The other, more subtle benefit, is to minimize difference between the various
calling conventions.
rdar://16039676
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201193 91177308-0d34-0410-b5e6-96231b3b80d8
Similarly to the vshrn instructions, these are simple zext/sext + trunc
operations. Using normal LLVM IR should allow for better code, and more sharing
with the AArch64 backend.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201093 91177308-0d34-0410-b5e6-96231b3b80d8
For A- and R-class processors, r12 is not normally callee-saved, but is for
interrupt handlers. See AAPCS, 5.3.1.1, "Use of IP by the linker".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201089 91177308-0d34-0410-b5e6-96231b3b80d8
vshrn is just the combination of a right shift and a truncate (and the limits
on the immediate value actually mean the signedness of the shift doesn't
matter). Using that representation allows us to get rid of an ARM-specific
intrinsic, share more code with AArch64 and hopefully get better code out of
the mid-end optimisers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201085 91177308-0d34-0410-b5e6-96231b3b80d8
According to the AAPCS, when a CPRC is allocated to the stack, all other
VFP registers should be marked as unavailable.
I have also modified the rules for allocating non-CPRCs to the stack, to make
it more explicit that all GPRs must be made unavailable. I cannot think of a
case where the old version would produce incorrect answers, so there is no test
for this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200970 91177308-0d34-0410-b5e6-96231b3b80d8
Fix a bug triggered in IfConverterTriangle when CvtBB has multiple predecessors
by getting the weights before removing a successor.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200958 91177308-0d34-0410-b5e6-96231b3b80d8
This patch fixes the ldr-pseudo implementation to work when used in
inline assembly. The fix is to move arm assembler constant pools
from the ARMAsmParser class to the ARMTargetStreamer class.
Previously we kept the assembler generated constant pools in the
ARMAsmParser object. This does not work for inline assembly because
a new parser object is created for each blob of inline assembly.
This patch moves the constant pools to the ARMTargetStreamer class
so that the constant pool will remain alive for the entire code
generation process.
An ARMTargetStreamer class is now required for the arm backend.
There was no existing implementation for MachO, only Asm and ELF.
Instead of creating an empty MachO subclass, we decided to make the
ARMTargetStreamer a non-abstract class and provide default
(llvm_unreachable) implementations for the non constant-pool related
methods.
Differential Revision: http://llvm-reviews.chandlerc.com/D2638
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200777 91177308-0d34-0410-b5e6-96231b3b80d8
There was an extremely confusing proliferation of LLVM intrinsics to implement
the vacge & vacgt instructions. This combines them all into two polymorphic
intrinsics, shared across both backends.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200768 91177308-0d34-0410-b5e6-96231b3b80d8
Missing braces on if meant we inserted both ARM and Thumb load for a litpool
entry. This didn't end well.
rdar://problem/15959157
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200752 91177308-0d34-0410-b5e6-96231b3b80d8
A bunch of test cases needed to be cleaned up for this, many my fault -
when implementid imported modules I updated test cases by simply
duplicating the prior metadata field - which wasn't always the empty
metadata entry.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200731 91177308-0d34-0410-b5e6-96231b3b80d8
Some of the SHA instructions take a scalar i32 as one argument (largely because
they work on 160-bit hash fragments). This wasn't reflected in the IR
previously, with ARM and AArch64 choosing different types (<4 x i32> and <1 x
i32> respectively) which was ugly.
This makes all the affected intrinsics take a uniform "i32", allowing them to
become non-polymorphic at the same time.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200706 91177308-0d34-0410-b5e6-96231b3b80d8
This changes the PrologueEpilogInserter and LocalStackSlotAllocation passes to
follow the extended stack layout rules for sspstrong and sspreq.
The sspstrong layout rules are:
1. Large arrays and structures containing large arrays (>= ssp-buffer-size)
are closest to the stack protector.
2. Small arrays and structures containing small arrays (< ssp-buffer-size) are
2nd closest to the protector.
3. Variables that have had their address taken are 3rd closest to the
protector.
Differential Revision: http://llvm-reviews.chandlerc.com/D2546
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200601 91177308-0d34-0410-b5e6-96231b3b80d8
When converting from "or + br" to two branches, or converting from
"and + br" to two branches, we correctly update the edge weights of
the two branches.
The previous attempt at r200431 was reverted at r200434 because of
two testing case failures. I modified my patch a little, but forgot
to re-run "make check-all".
Testing case CodeGen/ARM/lsr-unfolded-offset.ll is updated because of
the patch's impact on branch probability which causes changes in
spill placement.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200502 91177308-0d34-0410-b5e6-96231b3b80d8
This commit only handles IfConvertTriangle. To update edge weights
of a successor, one interface is added to MachineBasicBlock:
/// Set successor weight of a given iterator.
setSuccWeight(succ_iterator I, uint32_t weight)
An existing testing case test/CodeGen/Thumb2/v8_IT_5.ll is updated,
since we now correctly update the edge weights, the cold block
is placed at the end of the function and we jump to the cold block.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200428 91177308-0d34-0410-b5e6-96231b3b80d8
After all hard work to implement the EHABI and with the test-suite
passing, it's time to turn it on by default and allow users to
disable it as a work-around while we fix the eventual bugs that show
up.
This commit also remove the -arm-enable-ehabi-descriptors, since we
want the tables to be printed every time the EHABI is turned on
for non-Darwin ARM targets.
Although MCJIT EHABI is not working yet (needs linking with the right
libraries), this commit also fixes some relocations on MCJIT regarding
the EH tables/lib calls, and update some tests to avoid using EH tables
when none are needed.
The EH tests in the test-suite that were previously disabled on ARM
now pass with these changes, so a follow-up commit on the test-suite
will re-enable them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200388 91177308-0d34-0410-b5e6-96231b3b80d8
