Since r241097, `DIBuilder` has only created distinct `DICompileUnit`s.
The backend is liable to start relying on that (if it hasn't already),
so make uniquable `DICompileUnit`s illegal and automatically upgrade old
bitcode. This is a nice cleanup, since we can remove an unnecessary
`DenseSet` (and the associated uniquing info) from `LLVMContextImpl`.
Almost all the testcases were updated with this script:
git grep -e '= !DICompileUnit' -l -- test |
grep -v test/Bitcode |
xargs sed -i '' -e 's,= !DICompileUnit,= distinct !DICompileUnit,'
I imagine something similar should work for out-of-tree testcases.
llvm-svn: 243885
This is necessary for WatchOS support, where the compact unwind format assumes
this kind of layout. For now we only want this on Swift-like CPUs though, where
it's been the Xcode behaviour for ages. Also, since it can expand the prologue
we don't want it at -Oz.
llvm-svn: 243884
Instead of cloning distinct `MDNode`s when linking in a module, just
move them over. The module linker destroys the source module, so the
old node would otherwise just be leaked on the context. Create the new
node in place. This also reduces the number of cloned uniqued nodes
(since it's less likely their operands have changed).
This mapping strategy is only correct when we're discarding the source,
so the linker turns it on via a ValueMapper flag, `RF_MoveDistinctMDs`.
There's nothing observable in terms of `llvm-link` output here: the
linked module should be semantically identical.
I'll be adding more 'distinct' nodes to the debug info metadata graph in
order to break uniquing cycles, so the benefits of this will partly come
in future commits. However, we should get some gains immediately, since
we have a fair number of 'distinct' `DILocation`s being linked in.
llvm-svn: 243883
Instead of always showing/printing all functions, a class derived from
the DOTViewer class can overwrite the set of functions that will be
processed.
This will be used (and tested) by Polly's scop viewers, but other users
can be imagined as well.
llvm-svn: 243881
Summary:
This is useful for PNaCl's `RewriteAtomics` pass. NaCl intrinsics don't exist for some of the more exotic RMW instructions, so by refactoring this function into its own, `RewriteAtomics` can share code rewriting those atomics with `AtomicExpand` while additionally saving a few cycles by generating the `cmpxchg` NaCl-specific intrinsic with the callback. Without this patch, `RewriteAtomics` would require two extra passes over functions, by first requiring use of the full `AtomicExpand` pass to just expand the leftover exotic RMWs and then running itself again to expand resulting `cmpxchg`s.
NFC
Reviewers: jfb
Subscribers: jfb, llvm-commits
Differential Revision: http://reviews.llvm.org/D11422
llvm-svn: 243880
* generate function with string attribute using API,
* dump it in LL format,
* try to parse.
Add parser support for string attributes to fix the issue.
Reviewed By: reames, hfinkel
Differential Revision: http://reviews.llvm.org/D11058
llvm-svn: 243877
Summary:
Modify the cost calculation function for interleaved accesses
to use the target-specific costs for insert/extract element and
memory operations.
This better models the case where the backend can't match
the interleaved group, and we are forced to use a wide load
and shuffle vectors.
Interleaved accesses are not enabled by default, so this shouldn't
cause a performance change.
Reviewers: jmolloy
Subscribers: jmolloy, llvm-commits
Differential Revision: http://reviews.llvm.org/D11718
llvm-svn: 243875
Enabling merging of extern globals appears to be generally either beneficial or
harmless. On some benchmarks suites (on Cortex-M4F, Cortex-A9, and Cortex-A57)
it gives improvements in the 1-5% range, but in the rest the overall effect is
zero.
Differential Revision: http://reviews.llvm.org/D10966
llvm-svn: 243874
Adjust the GlobalMergeOnExternal option so that the default behaviour is to
do whatever the Target thinks is best. Explicitly enabled or disabling the
option will override this default.
Differential Revision: http://reviews.llvm.org/D10965
llvm-svn: 243873
The test/DebugInfo/dwarfdump-macho-universal.test test added in r243862 uses
an input from another test's directory (test/tools/dsymutil/Inputs/fat-test.o)
which breaks our test setup.
Copying the required test input to the test's Input directory to fix the issue.
llvm-svn: 243872
In http://reviews.llvm.org/rL215382, IT forming was made more conservative under
the belief that a flag-setting instruction was unpredictable inside an IT block on ARMv6M.
But actually, ARMv6M doesn't even support IT blocks so that's impossible. In the ARMARM for
v7M, v7AR and v8AR it states that the semantics of such an instruction changes inside an
IT block - it doesn't set the flags. So actually it is fine to use one inside an IT block
as long as the flags register is dead afterwards.
This gives significant performance improvements in a variety of MPEG based workloads.
Differential revision: http://reviews.llvm.org/D11680
llvm-svn: 243869
This is a minor optimization to only check for unresolved operands
inside `mapDistinctNode()` if the operands have actually changed. This
shouldn't really cause any change in behaviour. I didn't actually see a
slowdown in a profile, I was just poking around nearby and saw the
opportunity.
llvm-svn: 243866
Summary: This currently sets the shift amount RHS to the same type as the LHS, and assumes that the LHS is a simple type. This isn't currently the case e.g. with weird integers sizes, but will eventually be true and will assert if not. That's what you get for having an experimental backend: break it and you get to keep both pieces. Most backends either set the RHS to MVT::i32 or MVT::i64, but WebAssembly is a virtual ISA and tries to have regular-looking binary operations where both operands are the same type (even if a 64-bit RHS shifter is slightly silly, hey it's free!).
Subscribers: llvm-commits, sunfish, jfb
Differential Revision: http://reviews.llvm.org/D11715
llvm-svn: 243860
Change `DIELoc` and `DIEBlock` to stop inheriting from `DIE`, instead
inheriting from `DIEValueList` to share the value storage API. This
awkward bit of code-sharing was also fairly confusing: neither `DIELoc`
nor `DIEBlock` represents a `DIE`, so why would they inherit from it?
Aside from the API cleanup, this should improve debug info memory usage
in the backend, since it shaves five pointers off of every `DIELoc` and
`DIEBlock`. I haven't bothered to measure the savings, though.
llvm-svn: 243858
Split out a helper `printValues()` for printing `DIEBlock` and `DIELoc`,
instead of relying on `DIE::print()`. The shared code was actually
fairly small there. No functionality change intended.
llvm-svn: 243856
Rewrite `DIEValueList` as a subclass of `DIE`, renaming its API to match
`DIE`'s. This is preparation for changing `DIEBlock` and `DIELoc` to
stop inheriting from `DIE` and inherit directly from `DIEValueList`.
I thought about leaving this as a has-a relationship (and changing
`DIELoc` and `DIEBlock` to also have-a `DIEValueList`), but that seemed
to require a fair bit more boilerplate and I think it needed more
changes to the `DwarfUnit` API than this will.
No functionality change intended here.
llvm-svn: 243854
The XformToShuffleWithZero method currently checks AND masks at the per-lane level for all-one and all-zero constants and attempts to convert them to legal shuffle clear masks.
This patch generalises XformToShuffleWithZero, splitting and checking the sub-lanes of the constants down to the byte level to see if any legal shuffle clear masks are possible. This allows a lot of masks (often from legalization or truncation) to be folded into existing shuffle patterns and removes a lot of constant mask loading.
There are a few examples of poor shuffle lowering that are exposed by this patch that will be cleaned up in future patches (e.g. merging shuffles that are separated by bitcasts, x86 legalized v8i8 zero extension uses PMOVZX+AND+AND instead of AND+PMOVZX, etc.)
Differential Revision: http://reviews.llvm.org/D11518
llvm-svn: 243831
Remove some unnecessary explicit special members in Hexagon that, once
removed, allow the other implicit special members to be used without
depending on deprecated features.
llvm-svn: 243825
Summary: Also test 64-bit integers, except shifts for now which are broken because isel dislikes the 32-bit truncate that precedes them.
Reviewers: sunfish
Subscribers: llvm-commits, jfb
Differential Revision: http://reviews.llvm.org/D11699
llvm-svn: 243822
Various targets use std::swap on specific MCAsmOperands (ARM and
possibly Hexagon as well). It might be helpful to mark those subclasses
as final, to ensure that the availability of move/copy operations can't
lead to slicing. (same sort of requirements as the non-vitual dtor -
protected or a final class)
llvm-svn: 243820
This commit fixes a bug in the class 'SIInstrInfo' where the implicit register
machine operands were added to a machine instruction in an incorrect order -
the implicit uses were added before the implicit defs.
I found this bug while working on moving the implicit register operand
verification code from the MIR parser to the machine verifier.
This commit also makes the method 'addImplicitDefUseOperands' in the machine
instruction class public so that it can be reused in the 'SIInstrInfo' class.
Reviewers: Matt Arsenault
Differential Revision: http://reviews.llvm.org/D11689
llvm-svn: 243799
Summary:
For example, in
struct S {
int *x;
int *y;
};
__global__ void foo(S s) {
int *b = s.y;
// use b
}
"b" is guaranteed to point to global. NVPTX should emit ld.global/st.global for
accessing "b".
Reviewers: jholewinski
Subscribers: llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11505
llvm-svn: 243790
Summary:
Use -1 as numoperands for the return SDTypeProfile, denoting that return is variadic. Note that the patterns in InstrControl.td still need to match the inputs, so this ins't an "anything goes" variadic on ret!
The next step will be to handle other local types (not just int32).
Reviewers: sunfish
Subscribers: llvm-commits, jfb
Differential Revision: http://reviews.llvm.org/D11692
llvm-svn: 243783
Successive versions of LLVM should retain the ability to parse bitcode
generated by old releases of the compiler. This adds a bitcode format
compatibility test, which is intended to provide good (albeit not
entirely exhaustive) coverage of the current LangRef.
This also includes compatibility tests for LLVM 3.6. After every 3.X.0
release, the compatibility.ll file from the 3.X branch should be copied
to compatibility-3.X.ll on trunk, and the 3.X.0 release used to generate
a corresponding bitcode file.
Patch by Vedant Kumar!
llvm-svn: 243779
When encountering a scattered relocation, the code would assert trying to
access an unexisting section. I couldn't find a way to expose the result
of the processing of a scattered reloc, and I'm really unsure what the
right thing to do is. This patch just skips them during the processing in
DwarfContext and adds a mach-o file to the tests that exposed the asserting
behavior.
(This is a new failure that is being exposed by Rafael's recent work on
the libObject interfaces. I think the wrong behavior has always happened,
but now it's asserting)
llvm-svn: 243778
Remove the fake `DW_TAG_auto_variable` and `DW_TAG_arg_variable` tags,
using `DW_TAG_variable` in their place Stop exposing the `tag:` field at
all in the assembly format for `DILocalVariable`.
Most of the testcase updates were generated by the following sed script:
find test/ -name "*.ll" -o -name "*.mir" |
xargs grep -l 'DILocalVariable' |
xargs sed -i '' \
-e 's/tag: DW_TAG_arg_variable, //' \
-e 's/tag: DW_TAG_auto_variable, //'
There were only a handful of tests in `test/Assembly` that I needed to
update by hand.
(Note: a follow-up could change `DILocalVariable::DILocalVariable()` to
set the tag to `DW_TAG_formal_parameter` instead of `DW_TAG_variable`
(as appropriate), instead of having that logic magically in the backend
in `DbgVariable`. I've added a FIXME to that effect.)
llvm-svn: 243774
This introduces new instructions neccessary to implement MSVC-compatible
exception handling support. Most of the middle-end and none of the
back-end haven't been audited or updated to take them into account.
Differential Revision: http://reviews.llvm.org/D11097
llvm-svn: 243766
Replace the general `createLocalVariable()` with two more specific
functions: `createParameterVariable()` and `createAutoVariable()`, and
rewrite the documentation.
Besides cleaning up the API, this avoids exposing the fake DWARF tags
`DW_TAG_arg_variable` and `DW_TAG_auto_variable` to frontends, and is
preparation for removing them completely.
llvm-svn: 243764
Summary:
This prints assembly for int32 integer operations defined in WebAssemblyInstrInteger.td only, with major caveats:
- The operation names are currently incorrect.
- Other integer and floating-point types will be added later.
- The printer isn't factored out to handle recursive AST code yet, since it can't even handle control flow anyways.
- The assembly format isn't full s-expressions yet either, this will be added later.
- This currently disables PrologEpilogCodeInserter as well as MachineCopyPropagation becasue they don't like virtual registers, which WebAssembly likes quite a bit. This will be fixed by factoring out NVPTX's change (currently a fork of PrologEpilogCodeInserter).
Reviewers: sunfish
Subscribers: llvm-commits, jfb
Differential Revision: http://reviews.llvm.org/D11671
llvm-svn: 243763
Add i16, i32, i64 imul machine instructions to the list of reassociation
candidates.
A new bit of logic is needed to handle integer instructions: they have an
implicit EFLAGS operand, so we have to make sure it's dead in order to do
any reassociation with integer ops.
Differential Revision: http://reviews.llvm.org/D11660
llvm-svn: 243756
This makes llvm-nm consistent with binutils nm on executables and DLLs.
For a vanilla hello world executable, the address of main should include
the default image base of 0x400000.
llvm-svn: 243755
Summary:
Favor the extended reg patterns over the shifted reg patterns that match
only the operand shift and not the full sign/zero extend and shift.
Reviewers: jmolloy, t.p.northover
Subscribers: mcrosier, aemerson, llvm-commits, rengolin
Differential Revision: http://reviews.llvm.org/D11569
llvm-svn: 243753
This patch is a follow up from r240560 and is a step further into
mitigating the compile time performance issues in CaptureTracker.
By providing the CaptureTracker with a "cached ordered basic block"
instead of computing it every time, MemDepAnalysis can use this cache
throughout its calls to AA->callCapturesBefore, avoiding to recompute it
for every scanned instruction. In the same testcase used in r240560,
compile time is reduced from 2min to 30s.
This also fixes PR22348.
rdar://problem/19230319
Differential Revision: http://reviews.llvm.org/D11364
llvm-svn: 243750
Summary:
This prevents vreg260 and D7 from being merged in:
%vreg260<def> = LDC1 ...
JAL <ga:@sin>, <regmask ... list not containing D7 ...>
%D7<def> = COPY %vreg260; ...
Doing so is not valid because the JAL clobbers the D7.
This fixes the almabench regression in the LLVM 3.7.0 release branch.
Reviewers: MatzeB
Subscribers: MatzeB, qcolombet, hans, llvm-commits
Differential Revision: http://reviews.llvm.org/D11649
llvm-svn: 243745
This is to fix an incorrect error when trying to initialize
DwarfNumbers with a !cast<int> of a bits initializer.
getValuesAsListOfInts("DwarfNumbers") would not see an IntInit
and instead the cast, so would give up.
It seems likely that this could be generalized to attempt
the convertInitializerTo for any type. I'm not really sure
why the existing code seems to special case the string cast cases
when convertInitializerTo seems like it should generally handle this
sort of thing.
llvm-svn: 243722
For a modulo (reminder) operation,
clang -target armv7-none-linux-gnueabi generates "__modsi3"
clang -target armv7-none-eabi generates "__aeabi_idivmod"
clang -target armv7-linux-androideabi generates "__modsi3"
Android bionic libc doesn't provide a __modsi3, instead it provides a
"__aeabi_idivmod". This patch fixes the LLVM ARMISelLowering to generate
the correct call when ever there is a modulo operation.
Differential Revision: http://reviews.llvm.org/D11661
llvm-svn: 243717
Fixing MinSize attribute handling was discussed in D11363.
This is a prerequisite patch to doing that.
The handling of OptSize when lowering mem* functions was broken
on Darwin because it wants to ignore -Os for these cases, but the
existing logic also made it ignore -Oz (MinSize).
The Linux change demonstrates a widespread problem. The backend
doesn't usually recognize the MinSize attribute by itself; it
assumes that if the MinSize attribute exists, then the OptSize
attribute must also exist.
Fixing this more generally will be a follow-on patch or two.
Differential Revision: http://reviews.llvm.org/D11568
llvm-svn: 243693
This uncovered latent bugs previously:
http://reviews.llvm.org/D10403
...but it's time to try again because internal tests aren't finding more.
If time passes and no other bugs are reported, we can remove this cl::opt.
llvm-svn: 243687
Summary: Also provide the associated assertion when CodeGen starts.
Reviewers: echristo
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11654
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 243682
The patch changes the SLPVectorizer::vectorizeStores to choose the immediate
succeeding or preceding candidate for a store instruction when it has multiple
consecutive candidates. In this way it has better chance to find more slp
vectorization opportunities.
Differential Revision: http://reviews.llvm.org/D10445
llvm-svn: 243666
I'm not sure what reasons the comment here could have
had for not setting these. Without these set, there is
an assertion hit during DWARF emission.
llvm-svn: 243661
Copy implementation of applyFixup from AArch64 with AArch64 bits
ripped out.
Tests will be included with a later commit. Several other
problems must be fixed before binary debug info emission
will work.
llvm-svn: 243660
Summary:
Replace the switch on instruction opcode with a switch on register size.
This way we don't need to update the switch statement when we add new
SMRD variants.
Reviewers: arsenm
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11601
llvm-svn: 243652
Summary:
This function is never called. isReallyTriviallyReMaterializable() is
the function that should be implemented instead.
Reviewers: arsenm
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11620
llvm-svn: 243651
Update the debug info in the check-lines because the change in r243638
introduced a constant initialization before the prologue's end as part
of a register spill.
llvm-svn: 243640
Summary:
This hidden option would disable code generation through FastISel by
default. It was removed from the available options and from the
Fast-ISel tests that required it in order to run the tests.
Reviewers: dsanders
Subscribers: qcolombet, llvm-commits
Differential Revision: http://reviews.llvm.org/D11610
llvm-svn: 243638
Summary:
Previously, we would sign-extend non-boolean negative constants and
zero-extend otherwise. This was problematic for PHI instructions with
negative values that had a type with bitwidth less than that of the
register used for materialization.
More specifically, ComputePHILiveOutRegInfo() assumes the constants
present in a PHI node are zero extended in their container and
afterwards deduces the known bits.
For example, previously we would materialize an i16 -4 with the
following instruction:
addiu $r, $zero, -4
The register would end-up with the 32-bit 2's complement representation
of -4. However, ComputePHILiveOutRegInfo() would generate a constant
with the upper 16-bits set to zero. The SelectionDAG builder would use
that information to generate an AssertZero node that would remove any
subsequent trunc & zero_extend nodes.
In theory, we should modify ComputePHILiveOutRegInfo() to consult
target-specific hooks about the way they prefer to materialize the
given constants. However, git-blame reports that this specific code
has not been touched since 2011 and it seems to be working well for every
target so far.
Reviewers: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11592
llvm-svn: 243636
Summary:
Mips doesn't implement unw_getcontext() or libunwind::Registers_*::jumpto() yet
so we must disable libunwind for this release.
Reviewers: hans
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11563
llvm-svn: 243633
The reason I was passing this vector by value in the constructor so that
I wouldn't have to copy when initializing the corresponding member but
then I forgot the std::move.
The use-case is LoopDistribution which filters the checks then
std::moves it to LoopVersioning's constructor. With this interface we
can avoid any copies.
llvm-svn: 243616
Before, we were passing the pointer partitions to LAA. Now, we get all
the checks from LAA and filter out the checks within partitions in
LoopDistribution.
This effectively concludes the steps to move filtering memchecks from
LAA into its clients. There is still some cleanup left to remove the
unused interfaces in LAA that still take PtrPartition.
(Moving this functionality to LoopDistribution also requires
needsChecking on pointers to be made public.)
llvm-svn: 243613
This avoids stack overflows when the the compiler does not perform tail call
elimination. Apparently this happens for MSVC with the /Ob2 switch which
may be used by external code including this header.
Reported by and based on a patch from Jean-Francois Riendeau.
Related to rdar://21900756
llvm-svn: 243590
Bonus change to remove emacs major mode marker from SystemZMachineFunctionInfo.cpp because emacs already knows it's C++ from the extension. Also fix typo "appeary" in AMDGPUMCAsmInfo.h.
llvm-svn: 243585
Prevent all the unrelated LLVM options to appear in the -help output
by introducing a tool specific option category. As a drive-by improve
the wording of the help message.
llvm-svn: 243583
The dsymutil-classic -v option dumps the tool version rather than
putting it in verbose mode. Rename -v to -verbose and update the
tests that use it (in the process removing it from a few tests that
didn't require it anymore since the -dump-debug-map option was
introduced).
A followup commit will reintroduce the -v option that dumps the
version.
llvm-svn: 243582
This reverts commit r243567, which ultimately reapplies r243563.
The fix here was to use std::enable_if for overload resolution. Thanks to David
Blaikie for lots of help on this, and for the extra tests!
Original commit message follows:
For cases where we needed a foreach loop in reverse over a container,
we had to do something like
for (const GlobalValue *GV : make_range(TypeInfos.rbegin(),
TypeInfos.rend())) {
This provides a convenience method which shortens this to
for (const GlobalValue *GV : reverse(TypeInfos)) {
There are 2 versions of this, with a preference to the rbegin() version.
The first uses rbegin() and rend() to construct an iterator_range.
The second constructs an iterator_range from the begin() and end() methods
wrapped in std::reverse_iterator's.
Reviewed by David Blaikie.
llvm-svn: 243581
This patch improves the 32-bit target i64 constant matching to detect the shuffle vector splats that are introduced by i64 vector shift vectorization (D8416).
Differential Revision: http://reviews.llvm.org/D11327
llvm-svn: 243577
It's potentially more efficient on Cyclone, and from the optimization guides &
schedulers looks like it has no effect on Cortex-A53 or A57. In general you'd
expect a MOV to be about the most efficient instruction with its semantics,
even though the official "UXTW" alias is really a UBFX.
llvm-svn: 243576
This commit extracts the code that's used by the class 'MIRParserImpl' to parse
the machine basic block references into a new method named 'parseMBBReference'.
llvm-svn: 243572
This patch vectorizes the v2i64/v4i64 ASHR shift operations - the last remaining integer vector shifts that are still being transferred to/from the scalar unit to be completed.
Differential Revision: http://reviews.llvm.org/D11439
llvm-svn: 243569
This reverts commit r243563.
The GCC buildbots were extremely unhappy about this. Reverting while
we discuss a better way of doing overload resolution.
llvm-svn: 243567
For cases where we needed a foreach loop in reverse over a container,
we had to do something like
for (const GlobalValue *GV : make_range(TypeInfos.rbegin(),
TypeInfos.rend())) {
This provides a convenience method which shortens this to
for (const GlobalValue *GV : reverse(TypeInfos)) {
There are 2 versions of this, with a preference to the rbegin() version.
The first uses rbegin() and rend() to construct an iterator_range.
The second constructs an iterator_range from the begin() and end() methods
wrapped in std::reverse_iterator's.
Reviewed by David Blaikie.
llvm-svn: 243563
Summary:
returns_twice (most importantly, setjmp) functions are
optimization-hostile: if local variable is promoted to register, and is
changed between setjmp() and longjmp() calls, this update will be
undone. This is the reason why "man setjmp" advises to mark all these
locals as "volatile".
This can not be enough for ASan, though: when it replaces static alloca
with dynamic one, optionally called if UAR mode is enabled, it adds a
whole lot of SSA values, and computations of local variable addresses,
that can involve virtual registers, and cause unexpected behavior, when
these registers are restored from buffer saved in setjmp.
To fix this, just disable dynamic alloca and UAR tricks whenever we see
a returns_twice call in the function.
Reviewers: rnk
Subscribers: llvm-commits, kcc
Differential Revision: http://reviews.llvm.org/D11495
llvm-svn: 243561
Making allowableAlignment() more accessible was suggested as a predecessor patch
for D10662, so I've pulled it into TargetLowering. This let's us remove 4 instances
of duplicate logic in LegalizeDAG.
There's a subtle functional change in the implementation: the existing
allowableAlignment() code was using getPrefTypeAlignment() when checking
alignment with the DataLayout and assumed that was fast. In this implementation,
we use getABITypeAlignment() and assume that is fast. See the TODO comment or the
discussion in the Phab review for future improvements in this implementation
(don't use the data layout at all).
There are no regression test changes from this difference, and I'm not sure how to
expose it via a test. I think we actually do want to provide the 'Fast' param when
checking this from DAGCombiner::MergeConsecutiveStores(). Ie, we shouldn't merge
stores if the new stores are not going to be fast. But that change will require
fixing allowsMisalignedMemoryAccess() overrides as noted in D10662.
Differential Revision: http://reviews.llvm.org/D10905
llvm-svn: 243549
ASan shadow on Android starts at address 0 for both historic and
performance reasons. This is possible because the platform mandates
-pie, which makes lower memory region always available.
This is not such a good idea on 64-bit platforms because of MAP_32BIT
incompatibility.
This patch changes Android/AArch64 mapping to be the same as that of
Linux/AAarch64.
llvm-svn: 243548