History log of /art/runtime/arch/arm/fault_handler_arm.cc
Revision Date Author Comments
57943810cfc789da890d73621741729da5feaaf8 07-Dec-2017 Andreas Gampe <agampe@google.com> ART: Replace base/logging with android-base/logging

Replace wherever possible. ART's base/logging is now mainly VLOG
and initialization code that is unnecessary to pull in and makes
changes to verbose logging more painful than they have to be.

Test: m test-art-host
Change-Id: I3e3a4672ba5b621e57590a526c7d1c8b749e4f6e
33bff25bcd7a02d35c54f63740eadb1a4833fc92 01-Nov-2017 Vladimir Marko <vmarko@google.com> ART: Make InstructionSet an enum class and add kLast.

Adding InstructionSet::kLast shall make it easier to encode
the InstructionSet in fewer bits using BitField<>. However,
introducing `kLast` into the `art` namespace is not a good
idea, so we change the InstructionSet to an enum class.
This also uncovered a case of InstructionSet::kNone being
erroneously used instead of vixl32::Condition::None(), so
it's good to remove `kNone` from the `art` namespace.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Change-Id: I6fa6168dfba4ed6da86d021a69c80224f09997a6
8cf9cb386cd9286d67e879f1ee501ec00d72a4e1 19-Jul-2017 Andreas Gampe <agampe@google.com> ART: Include cleanup

Let clang-format reorder the header includes.

Derived with:

* .clang-format:
BasedOnStyle: Google
IncludeIsMainRegex: '(_test|-inl)?$'

* Steps:
find . -name '*.cc' -o -name '*.h' | xargs sed -i.bak -e 's/^#include/ #include/' ; git commit -a -m 'ART: Include cleanup'
git-clang-format -style=file HEAD^
manual inspection
git commit -a --amend

Test: mmma art
Change-Id: Ia963a8ce3ce5f96b5e78acd587e26908c7a70d02
b486a98aadc95d80548953410cf23edba62259fa 01-Jun-2017 Andreas Gampe <agampe@google.com> ART: Introduce thread-current-inl.h

Factor out Thread::Current() code into its own -inl file to remove
transitive includes.

This requires at the same time correcting mutex.h, i.e., moving
some functions into mutex-inl.h.

Test: m test-art-host
Change-Id: I88f888b604e0897368d9b483edce6ce4332dd9c9
c6ea7d00ad069a2736f603daa3d8eaa9a1f8ea11 02-Feb-2017 Andreas Gampe <agampe@google.com> ART: Clean up art_method.h

Clean up the header. Fix up other headers including the -inl file,
in an effort to prune the include graph. Fix broken transitive
includes by making includes explicit. Introduce new -inl files
for method handles and reference visiting.

Test: source build/envsetup.sh && lunch aosp_angler-userdebug && mmma art
Test: source build/envsetup.sh && lunch aosp_mips64-userdebug && mmma art
Change-Id: I8f60f1160c2a702fdf3598149dae38f6fa6bc851
efd20cb2f63cf647c7d947d00e8987affefeb177 01-Mar-2017 Josh Gao <jmgao@google.com> Catch signals that happen inside a fault handler.

Unblock some signals (SIGABRT, SIGBUS, SIGSEGV) that could happen
inside of the ART internal fault handlers, to report crashes inside of
the signal handler. Because we can't use sigaction to change the
handler when this happens, because it modifies global state, add a new
member variable in Thread to track whether a call to the fault handler
is reentrant or not.

Remove the old nested signal implementation that attempted to do this.

Bug: http://b/35853436
Test: changed the #if 0 to #if 1, ran a dummy process that
threw a NullPointerException, inspected logcat
Change-Id: I04bb4a09433c6817933d64ec681ec433b528f2a5
3b7537bfc5a6b7ccb18b3970d8edf14b72464af7 13-Sep-2016 Vladimir Marko <vmarko@google.com> Revert "Revert "Use implicit null checks inside try blocks.""

Fix implicit checks in try blocks to emit stack maps.
Fix arm64 null expection from signal entrypoint to call
the runtime handler instead or simply jumping there.

On Nexus 9, AOSP ToT, the boot.oat size reduction is
prebuilt multi-part boot image:
- 32-bit boot.oat: -448KiB (-1.3%)
- 64-bit boot.oat: -528KiB (-1.2%)
on-device built single boot image:
- 32-bit boot.oat: -448KiB (-1.4%)
- 64-bit boot.oat: -528KiB (-1.3%)
Note that the oat files no longer contain dex files which
have been moved to vdex, so the percentages are not directly
comparable with the those reported in the original commit.

Test: Run ART test suite including gc-stress on host and Nexus 9.
Bug: 30212852
Bug: 31468464

This reverts commit 0719b5b9b458cb3eb9f0823f0dacdfe1a71214dd.

Change-Id: If8a9da8c11adf2aad203e93b6684ce16ed776285
0719b5b9b458cb3eb9f0823f0dacdfe1a71214dd 13-Sep-2016 Nicolas Geoffray <ngeoffray@google.com> Revert "Use implicit null checks inside try blocks."

Fails gcstress tests.

This reverts commit 7aa7560683626c7893011271c241b3265ded1dc3.

Change-Id: I4f5c89048b9ffddbafa02f3001e329ff87058ca2
7aa7560683626c7893011271c241b3265ded1dc3 07-Sep-2016 Vladimir Marko <vmarko@google.com> Use implicit null checks inside try blocks.

Make implicit null check entrypoint save all registers, use
platform-specific approach to still pass the fault address.
Allow implicit null checks in try blocks.

On Nexus 9, AOSP ToT, the boot.oat size reduction is
prebuilt multi-part boot image:
- 32-bit boot.oat: -452KiB (-0.7%)
- 64-bit boot.oat: -482KiB (-0.7%)
on-device built single boot image:
- 32-bit boot.oat: -444KiB (-0.7%)
- 64-bit boot.oat: -488KiB (-0.7%)

Test: Run ART test suite on host and Nexus 9.
Test: Build aosp_mips64-eng.
Change-Id: I279f3ab57e2e2f338131c5cac45c51b673bdca19
542451cc546779f5c67840e105c51205a1b0a8fd 26-Jul-2016 Andreas Gampe <agampe@google.com> ART: Convert pointer size to enum

Move away from size_t to dedicated enum (class).

Bug: 30373134
Bug: 30419309
Test: m test-art-host
Change-Id: Id453c330f1065012e7d4f9fc24ac477cc9bb9269
e8e1127da3f154fae8d2eb16a94203544a182159 28-Jun-2016 Nicolas Geoffray <ngeoffray@google.com> Do checks on the fault address when we think it's an NPE.

bug:29321958
Change-Id: I28f4da56eb3e0b48721d3ac41114858bc80daadb
f561aab4decda4ae559955f18eb04a3f48d8c706 19-Jun-2015 Narayan Kamath <narayan@google.com> fault_handler : debug output sp in hex and not decimal.

Easier to compare against hex values in tombstones and debuggerd
dumps.

Change-Id: I4a4512ea1ce5872fdb6b41e824fa3475dfcfb71d
3d21bdf8894e780d349c481e5c9e29fe1556051c 22-Apr-2015 Mathieu Chartier <mathieuc@google.com> Move mirror::ArtMethod to native

Optimizing + quick tests are passing, devices boot.

TODO: Test and fix bugs in mips64.

Saves 16 bytes per most ArtMethod, 7.5MB reduction in system PSS.
Some of the savings are from removal of virtual methods and direct
methods object arrays.

Bug: 19264997

(cherry picked from commit e401d146407d61eeb99f8d6176b2ac13c4df1e33)

Change-Id: I622469a0cfa0e7082a2119f3d6a9491eb61e3f3d

Fix some ArtMethod related bugs

Added root visiting for runtime methods, not currently required
since the GcRoots in these methods are null.

Added missing GetInterfaceMethodIfProxy in GetMethodLine, fixes
--trace run-tests 005, 044.

Fixed optimizing compiler bug where we used a normal stack location
instead of double on ARM64, this fixes the debuggable tests.

TODO: Fix JDWP tests.

Bug: 19264997

Change-Id: I7c55f69c61d1b45351fd0dc7185ffe5efad82bd3

ART: Fix casts for 64-bit pointers on 32-bit compiler.

Bug: 19264997
Change-Id: Ief45cdd4bae5a43fc8bfdfa7cf744e2c57529457

Fix JDWP tests after ArtMethod change

Fixes Throwable::GetStackDepth for exception event detection after
internal stack trace representation change.

Adds missing ArtMethod::GetInterfaceMethodIfProxy call in case of
proxy method.

Bug: 19264997
Change-Id: I363e293796848c3ec491c963813f62d868da44d2

Fix accidental IMT and root marking regression

Was always using the conflict trampoline. Also included fix for
regression in GC time caused by extra roots. Most of the regression
was IMT.

Fixed bug in DumpGcPerformanceInfo where we would get SIGABRT due to
detached thread.

EvaluateAndApplyChanges:
From ~2500 -> ~1980
GC time: 8.2s -> 7.2s due to 1s less of MarkConcurrentRoots

Bug: 19264997
Change-Id: I4333e80a8268c2ed1284f87f25b9f113d4f2c7e0

Fix bogus image test assert

Previously we were comparing the size of the non moving space to
size of the image file.

Now we properly compare the size of the image space against the size
of the image file.

Bug: 19264997
Change-Id: I7359f1f73ae3df60c5147245935a24431c04808a

[MIPS64] Fix art_quick_invoke_stub argument offsets.

ArtMethod reference's size got bigger, so we need to move other args
and leave enough space for ArtMethod* and 'this' pointer.

This fixes mips64 boot.

Bug: 19264997
Change-Id: I47198d5f39a4caab30b3b77479d5eedaad5006ab
e401d146407d61eeb99f8d6176b2ac13c4df1e33 22-Apr-2015 Mathieu Chartier <mathieuc@google.com> Move mirror::ArtMethod to native

Optimizing + quick tests are passing, devices boot.

TODO: Test and fix bugs in mips64.

Saves 16 bytes per most ArtMethod, 7.5MB reduction in system PSS.
Some of the savings are from removal of virtual methods and direct
methods object arrays.

Bug: 19264997
Change-Id: I622469a0cfa0e7082a2119f3d6a9491eb61e3f3d
2cebb24bfc3247d3e9be138a3350106737455918 22-Apr-2015 Mathieu Chartier <mathieuc@google.com> Replace NULL with nullptr

Also fixed some lines that were too long, and a few other minor
details.

Change-Id: I6efba5fb6e03eb5d0a300fddb2a75bf8e2f175cb
9415886d879a7459ee9a3c6613f1a2687c87f08a 03-Apr-2015 Andreas Gampe <agampe@google.com> ART: Avoid obvious segfault in arm & x86 fault handler

These handlers need to read an instruction to determine where to
look for info. Don't try to read from pc=0.

Bug: 20040863
Change-Id: I38b56dc6dd806df22e608ee8d46c4091a738e4bc
d582fa4ea62083a7598dded5b82dc2198b3daac7 06-Nov-2014 Ian Rogers <irogers@google.com> Instruction set features for ARM64, MIPS and X86.

Also, refactor how feature strings are handled so they are additive or
subtractive.
Make MIPS have features for FPU 32-bit and MIPS v2. Use in the quick compiler
rather than #ifdefs that wouldn't have worked in cross-compilation.
Add SIMD features for x86/x86-64 proposed in:
https://android-review.googlesource.com/#/c/112370/

Bug: 18056890

Change-Id: Ic88ff84a714926bd277beb74a430c5c7d5ed7666
c4f990eab0486be624c271ebe08d4ed6c2783c42 04-Nov-2014 Chih-Hung Hsieh <chh@google.com> Add ATTRIBUTE_UNUSED to unused parameters.

They are reported by Clang compiler.

BUG: 18244071
Change-Id: I3ebf7a9c324490adbf1135f21818c7ad83c83f3d
8ce6b9040747054b444a7fa706503cd257801936 26-Aug-2014 Dave Allison <dallison@google.com> Handle nested signals

This allows for signals to be raised inside the ART signal handler.
This can occur when the JavaStackTraceHandler attempts to generate
a stack trace and something goes wrong.

It also fixes an issue where the fault manager was not being
correctly shut down inside the signal chaining code. In this
case the signal handler was not restored to the original.

Bug: 17006816
Bug: 17133266

(cherry picked from commit fabe91e0d558936ac26b98d2b4ee1af08f58831d)

Change-Id: I10730ef52d5d8d34610a5293253b3be6caf4829e
fabe91e0d558936ac26b98d2b4ee1af08f58831d 26-Aug-2014 Dave Allison <dallison@google.com> Handle nested signals

This allows for signals to be raised inside the ART signal handler.
This can occur when the JavaStackTraceHandler attempts to generate
a stack trace and something goes wrong.

It also fixes an issue where the fault manager was not being
correctly shut down inside the signal chaining code. In this
case the signal handler was not restored to the original.

Bug: 17006816
Bug: 17133266
Change-Id: I9c25bf4f6921e6a107aefbdf47d2c0db9f41508f
b038ba66a166fb264ca121632f447712e0973b5b 14-Aug-2014 Dave Allison <dallison@google.com> Revert "Revert "Reduce stack usage for overflow checks""

Fixes stack protection issue.
Fixes mac build issue.

This reverts commit 83b1940e6482b9d8feba5c492507735686650ea5.

Change-Id: I7ba17252882b23a740bcda2ea94aacf398255406
4cf00ba324f5f6884059796a6ba41937f32e1844 14-Aug-2014 Dave Allison <dallison@google.com> Revert "Reduce stack usage for overflow checks"

This reverts commit 63c051a540e6dfc806f656b88ac3a63e99395429.

Change-Id: I282a048994fcd130fe73842b16c21680053c592f
03c9785a8a6d712775cf406c4371d0227c44148f 14-Aug-2014 Dave Allison <dallison@google.com> Revert "Revert "Reduce stack usage for overflow checks""

Fixes stack protection issue.
Fixes mac build issue.

This reverts commit 83b1940e6482b9d8feba5c492507735686650ea5.

Change-Id: I7ba17252882b23a740bcda2ea94aacf398255406
83b1940e6482b9d8feba5c492507735686650ea5 14-Aug-2014 Dave Allison <dallison@google.com> Revert "Reduce stack usage for overflow checks"

This reverts commit 63c051a540e6dfc806f656b88ac3a63e99395429.

Change-Id: I282a048994fcd130fe73842b16c21680053c592f
63c051a540e6dfc806f656b88ac3a63e99395429 26-Jul-2014 Dave Allison <dallison@google.com> Reduce stack usage for overflow checks

This reduces the stack space reserved for overflow checks to 12K, split
into an 8K gap and a 4K protected region. GC needs over 8K when running
in a stack overflow situation.

Also prevents signal runaway by detecting a signal inside code that
resulted from a signal handler invokation. And adds a max signal count to
the SignalTest to prevent it running forever.

Also reduces the number of iterations for the InterfaceTest as this was
taking (almost) forever with the --trace option on run-test.

Bug: 15435566

Change-Id: Id4fd46f22d52d42a9eb431ca07948673e8fda694

Conflicts:
compiler/optimizing/code_generator_x86_64.cc
runtime/arch/x86/fault_handler_x86.cc
runtime/arch/x86_64/quick_entrypoints_x86_64.S
b0f05b9654eb005bc8c8e15f615a7f5a312f640c 17-Jul-2014 Dave Allison <dallison@google.com> Add implicit checks for x86_64 architecture.

This combines the x86 and x86_64 fault handlers into one. It also
merges in the change to the entrypoints for X86_64.

Replaces generic instruction length calculator with one that only
works with the specific instructions we use.

Bug: 16256184

Change-Id: I1e8ab5ad43f46060de9597615b423c89a836035c
Signed-off-by: Chao-ying Fu <chao-ying.fu@intel.com>
648d7112609dd19c38131b3e71c37bcbbd19d11e 26-Jul-2014 Dave Allison <dallison@google.com> Reduce stack usage for overflow checks

This reduces the stack space reserved for overflow checks to 12K, split
into an 8K gap and a 4K protected region. GC needs over 8K when running
in a stack overflow situation.

Also prevents signal runaway by detecting a signal inside code that
resulted from a signal handler invokation. And adds a max signal count to
the SignalTest to prevent it running forever.

Also reduces the number of iterations for the InterfaceTest as this was
taking (almost) forever with the --trace option on run-test.

Bug: 15435566

Change-Id: Id4fd46f22d52d42a9eb431ca07948673e8fda694
dfd3b47813c14c5f1607cbe7b10a28b1b2f29cbc 17-Jul-2014 Dave Allison <dallison@google.com> Add implicit checks for x86_64 architecture.

This combines the x86 and x86_64 fault handlers into one. It also
merges in the change to the entrypoints for X86_64.

Replaces generic instruction length calculator with one that only
works with the specific instructions we use.

Bug: 16256184

Change-Id: I1e8ab5ad43f46060de9597615b423c89a836035c
Signed-off-by: Chao-ying Fu <chao-ying.fu@intel.com>
0f45f22eb3c52f0ece4c56989180e79c6680d825 15-Jul-2014 Andreas Gampe <agampe@google.com> ART: Throw StackOverflowError in native code

Initialize stack-overflow errors in native code to be able to reduce
the preserved area size of the stack.

Includes a refactoring away from constexpr in instruction_set.h to allow
for easy changing of the values.

Bug: 16256184

(cherry picked from commit 7ea6f79bbddd69d5db86a8656a31aaaf64ae2582)

Change-Id: I117cc8485f43da5f0a470f0f5e5b3dc3b5a06246
7ea6f79bbddd69d5db86a8656a31aaaf64ae2582 15-Jul-2014 Andreas Gampe <agampe@google.com> ART: Throw StackOverflowError in native code

Initialize stack-overflow errors in native code to be able to reduce
the preserved area size of the stack.

Includes a refactoring away from constexpr in instruction_set.h to allow
for easy changing of the values.

Change-Id: I117cc8485f43da5f0a470f0f5e5b3dc3b5a06246
147eb41b53729ec8d5c188d1cac90964a51afb8a 11-Jul-2014 Dave Allison <dallison@google.com> Revert "Revert "Revert "Revert "Add implicit null and stack checks for x86""""

This reverts commit 0025a86411145eb7cd4971f9234fc21c7b4aced1.

Bug: 16256184
Change-Id: Ie0760a0c293aa3b62e2885398a8c512b7a946a73

Conflicts:
compiler/dex/quick/arm64/target_arm64.cc
compiler/image_test.cc
runtime/fault_handler.cc
69dfe51b684dd9d510dbcb63295fe180f998efde 11-Jul-2014 Dave Allison <dallison@google.com> Revert "Revert "Revert "Revert "Add implicit null and stack checks for x86""""

This reverts commit 0025a86411145eb7cd4971f9234fc21c7b4aced1.

Bug: 16256184
Change-Id: Ie0760a0c293aa3b62e2885398a8c512b7a946a73
7fb36ded9cd5b1d254b63b3091f35c1e6471b90e 10-Jul-2014 Dave Allison <dallison@google.com> Revert "Revert "Add implicit null and stack checks for x86""

Fixes x86_64 cross compile issue. Removes command line options
and property to set implicit checks - this is hard coded now.

This reverts commit 3d14eb620716e92c21c4d2c2d11a95be53319791.

Change-Id: I5404473b5aaf1a9c68b7181f5952cb174d93a90d
0025a86411145eb7cd4971f9234fc21c7b4aced1 11-Jul-2014 Nicolas Geoffray <ngeoffray@google.com> Revert "Revert "Revert "Add implicit null and stack checks for x86"""

Broke the build.

This reverts commit 7fb36ded9cd5b1d254b63b3091f35c1e6471b90e.

Change-Id: I9df0e7446ff0913a0e1276a558b2ccf6c8f4c949
34e826ccc80dc1cf7c4c045de6b7f8360d504ccf 29-May-2014 Dave Allison <dallison@google.com> Add implicit null and stack checks for x86

This adds compiler and runtime changes for x86
implicit checks. 32 bit only.

Both host and target are supported.
By default, on the host, the implicit checks are null pointer and
stack overflow. Suspend is implemented but not switched on.

Change-Id: I88a609e98d6bf32f283eaa4e6ec8bbf8dc1df78a
3d14eb620716e92c21c4d2c2d11a95be53319791 10-Jul-2014 Dave Allison <dallison@google.com> Revert "Add implicit null and stack checks for x86"

It breaks cross compilation with x86_64.

This reverts commit 34e826ccc80dc1cf7c4c045de6b7f8360d504ccf.

Change-Id: I34ba07821fc0a022fda33a7ae21850957bbec5e7
7cd26f355ba83be75b72ed628ed5ee84a3245c4f 19-Jun-2014 Andreas Gampe <agampe@google.com> ART: Target-dependent stack overflow, less check elision

Refactor the separate stack overflow reserved sizes from thread.h
into instruction_set.h and make sure they're used in the compiler.

Refactor the decision on when to elide stack overflow checks:
especially with large interpreter stack frames, it is not a good
idea to elide checks when the frame size is even close to the
reserved size. Currently enforce checks when the frame size is
>= 2KB, but make sure that frame sizes 1KB and below will elide
the checks (number from experience).

Bug: 15728765
Change-Id: I016bfd3d8218170cbccbd123ed5e2203db167c06
5cd33753b96d92c03e3cb10cb802e68fb6ef2f21 16-Apr-2014 Dave Allison <dallison@google.com> Handle implicit stack overflow without affecting stack walks

This changes the way in which implicit stack overflows are handled
to satisfy concerns about changes to the stack walk code.

Instead of creating a gap in the stack and checking for it in
the stack walker, use the ManagedStack infrastructure to concoct
an invisible gap that will never be seen by a stack walk.

Also, this uses madvise to tell the kernel that the main stack's
protected region will probably never be accessed, and instead
of using memset to map the pages in, use memcpy to read from
them. This will save 32K on the main stack.

Also adds a 'signals' verbosity level as per a review request.

Bug: 14066862
Change-Id: I5257305feeaea241d11e6aa6f021d2a81da20b81
8194963098247be6bca9cc4a54dbfa65c73e8ccc 02-May-2014 Vladimir Marko <vmarko@google.com> Replace CountOneBits and __builtin_popcount with POPCOUNT.

Clean up utils.h, make some functions constexpr.

Change-Id: I2399100280cbce81c3c4f5765f0680c1ddcb5883
d6ed642458c8820e1beca72f3d7b5f0be4a4b64b 10-Apr-2014 Dave Allison <dallison@google.com> Revert "Revert "Revert "Use trampolines for calls to helpers"""

This reverts commit f9487c039efb4112616d438593a2ab02792e0304.

Change-Id: Id48a4aae4ecce73db468587967968a3f7618b700
f9487c039efb4112616d438593a2ab02792e0304 09-Apr-2014 Dave Allison <dallison@google.com> Revert "Revert "Use trampolines for calls to helpers""

This reverts commit 081f73e888b3c246cf7635db37b7f1105cf1a2ff.

Change-Id: Ibd777f8ce73cf8ed6c4cb81d50bf6437ac28cb61

Conflicts:
compiler/dex/quick/mir_to_lir.h
081f73e888b3c246cf7635db37b7f1105cf1a2ff 07-Apr-2014 Dave Allison <dallison@google.com> Revert "Use trampolines for calls to helpers"

This reverts commit 754ddad084ccb610d0cf486f6131bdc69bae5bc6.

Change-Id: Icd979adee1d8d781b40a5e75daf3719444cb72e8
754ddad084ccb610d0cf486f6131bdc69bae5bc6 19-Feb-2014 Dave Allison <dallison@google.com> Use trampolines for calls to helpers

This is an ARM specific optimization to the compiler
that uses trampoline islands to make calls to runtime
helper functions. The intention is to reduce the size
of the generated code (by 2 bytes per call) without
affecting performance.

By default this is on when generating an OAT file. It is
off when compiling to memory.

To switch this off in dex2oat, use the command line option:
--no-helper-trampolines

Enhances disassembler to print the trampoline entry on the
BL instruction like this:

0xb6a850c0: f7ffff9e bl -196 (0xb6a85000) ; pTestSuspend

Bug: 12607709
Change-Id: I9202bdb7cf21252ad807bd48701f1f6ce8e3d0fe
8325296769a77ecf3ab647b5ab516f439f5b3206 04-Apr-2014 Dave Allison <dallison@google.com> Disable use of R4 as a promotable register

When we are using implicit suspend checks we can potentially
use r4 as a register into which variables can be promoted. However
the runtime doesn't save this and thus will corrupt it. Not good.

This disables the promotion of r4 until we can figure out how
to make the runtime save it properly.

Change-Id: Ib95ce93579e1c364de5ecc8e728f2cb7990da77a
c751fdcc9491c1b60c3db517fbc41bb98e92441f 31-Mar-2014 Mathieu Chartier <mathieuc@google.com> Add handler for printing java stack traces for compiled code SIGSEGV.

Added a new FaultHandler which attempts to print a java stack trace
when a SIGSEGV occurse in generated code. This should help debugging
compiler and GC related heap corruption.

Bug: 13725693
Bug: 12934910

Change-Id: Id54d83ea180c222eb86d449c61926e83f0b026ad
dd7624d2b9e599d57762d12031b10b89defc9807 15-Mar-2014 Ian Rogers <irogers@google.com> Allow mixing of thread offsets between 32 and 64bit architectures.

Begin a more full implementation x86-64 REX prefixes.
Doesn't implement 64bit thread offset support for the JNI compiler.

Change-Id: If9af2f08a1833c21ddb4b4077f9b03add1a05147
f943914730db8ad2ff03d49a2cacd31885d08fd7 27-Mar-2014 Dave Allison <dallison@google.com> Implement implicit stack overflow checks

This also fixes some failing run tests due to missing
null pointer markers.

The implementation of the implicit stack overflow checks introduces
the ability to have a gap in the stack that is skipped during
stack walk backs. This gap is protected against read/write and
is used to trigger a SIGSEGV at function entry if the stack
will overflow.

Change-Id: I0c3e214c8b87dc250cf886472c6d327b5d58653e
b373e091eac39b1a79c11f2dcbd610af01e9e8a9 21-Feb-2014 Dave Allison <dallison@google.com> Implicit null/suspend checks (oat version bump)

This adds the ability to use SEGV signals
to throw NullPointerException exceptions from Java code rather
than having the compiler generate explicit comparisons and
branches. It does this by using sigaction to trap SIGSEGV and when triggered
makes sure it's in compiled code and if so, sets the return
address to the entry point to throw the exception.

It also uses this signal mechanism to determine whether to check
for thread suspension. Instead of the compiler generating calls
to a function to check for threads being suspended, the compiler
will now load indirect via an address in the TLS area. To trigger
a suspend, the contents of this address are changed from something
valid to 0. A SIGSEGV will occur and the handler will check
for a valid instruction pattern before invoking the thread
suspension check code.

If a user program taps SIGSEGV it will prevent our signal handler
working. This will cause a failure in the runtime.

There are two signal handlers at present. You can control them
individually using the flags -implicit-checks: on the runtime
command line. This takes a string parameter, a comma
separated set of strings. Each can be one of:

none switch off
null null pointer checks
suspend suspend checks
all all checks

So to switch only suspend checks on, pass:
-implicit-checks:suspend

There is also -explicit-checks to provide the reverse once
we change the default.

For dalvikvm, pass --runtime-arg -implicit-checks:foo,bar

The default is -implicit-checks:none

There is also a property 'dalvik.vm.implicit_checks' whose value is the same
string as the command option. The default is 'none'. For example to switch on
null checks using the option:

setprop dalvik.vm.implicit_checks null

It only works for ARM right now.

Bumps OAT version number due to change to Thread offsets.

Bug: 13121132
Change-Id: If743849138162f3c7c44a523247e413785677370