Commit Graph

240 Commits

Author SHA1 Message Date
Yuri Gorshenin
eba0a96f8e [asan-asm-instrumentation] Fixed memory references which includes %rsp as a base or an index register.
Summary: [asan-asm-instrumentation] Fixed memory references which includes %rsp as a base or an index register.

Reviewers: eugenis

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5599

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219602 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-13 09:37:47 +00:00
David Blaikie
5f3c0bafeb DebugInfo+DFSan: Ensure that debug info references to llvm::Functions remain pointing to the underlying function when wrappers are created
This is somewhat the inverse of how similar bugs in DAE and ArgPromo
manifested and were addressed. In those passes, individual call sites
were visited explicitly, and then the old function was deleted. This
left the debug info with a null llvm::Function* that needed to be
updated to point to the new function.

In the case of DFSan, it RAUWs the old function with the wrapper, which
includes debug info. So now the debug info refers to the wrapper, which
doesn't actually have any instructions with debug info in it, so it is
ignored entirely - resulting in a DW_TAG_subprogram with no high/low pc,
etc. Instead, fix up the debug info to refer to the original function
after the RAUW messed it up.

Reviewed/discussed with Peter Collingbourne on the llvm-dev mailing
list.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219249 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-07 22:59:46 +00:00
Yuri Gorshenin
86e0844d1c [asan-asm-instrumentation] CFI directives are generated for .S files.
Summary: CFI directives are generated for .S files.

Reviewers: eugenis

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5520

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219199 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-07 11:03:09 +00:00
Duncan P. N. Exon Smith
83902832de Revert "Revert "DI: Fold constant arguments into a single MDString""
This reverts commit r218918, effectively reapplying r218914 after fixing
an Ocaml bindings test and an Asan crash.  The root cause of the latter
was a tightened-up check in `DILexicalBlock::Verify()`, so I'll file a
PR to investigate who requires the loose check (and why).

Original commit message follows.

--

This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString.  Integers are stringified and
a `\0` character is used as a separator.

Part of PR17891.

Note: I've attached my testcases upgrade scripts to the PR.  If I've
just broken your out-of-tree testcases, they might help.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219010 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-03 20:01:09 +00:00
Duncan P. N. Exon Smith
32e192aeb3 Revert "DI: Fold constant arguments into a single MDString"
This reverts commit r218914 while I investigate some bots.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218918 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-02 22:15:31 +00:00
Duncan P. N. Exon Smith
0917b70630 DI: Fold constant arguments into a single MDString
This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString.  Integers are stringified and
a `\0` character is used as a separator.

Part of PR17891.

Note: I've attached my testcases upgrade scripts to the PR.  If I've
just broken your out-of-tree testcases, they might help.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218914 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-02 21:56:57 +00:00
Adrian Prantl
02474a32eb Move the complex address expression out of DIVariable and into an extra
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.

Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.

By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.

The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)

This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.

What this patch doesn't do:

This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.

http://reviews.llvm.org/D4919
rdar://problem/17994491

Thanks to dblaikie and dexonsmith for reviewing this patch!

Note: I accidentally committed a bogus older version of this patch previously.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218787 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-01 18:55:02 +00:00
Adrian Prantl
10c4265675 Revert r218778 while investigating buldbot breakage.
"Move the complex address expression out of DIVariable and into an extra"

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218782 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-01 18:10:54 +00:00
Adrian Prantl
076fd5dfc1 Move the complex address expression out of DIVariable and into an extra
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.

Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.

By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.

The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)

This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.

What this patch doesn't do:

This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.

http://reviews.llvm.org/D4919
rdar://problem/17994491

Thanks to dblaikie and dexonsmith for reviewing this patch!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218778 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-01 17:55:39 +00:00
Lorenzo Martignoni
f49592dddc Introduce support for custom wrappers for vararg functions.
Differential Revision: http://reviews.llvm.org/D5412



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218671 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-30 12:33:16 +00:00
Kostya Serebryany
0e9d114865 [asan] don't instrument module CTORs that may be run before asan.module_ctor. This fixes asan running together -coverage
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218421 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-24 22:41:55 +00:00
Yuri Gorshenin
ca31084292 [asan-assembly-instrumentation] Added CFI directives to the generated instrumentation code.
Summary: [asan-assembly-instrumentation] Added CFI directives to the generated instrumentation code.

Reviewers: eugenis

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5189

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217482 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-10 09:45:49 +00:00
Kostya Serebryany
c9b2548b23 [asan] fix debug info produced for asan-coverage=2
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217106 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-03 23:24:18 +00:00
Kostya Serebryany
f12b1d8c7b [asan] add -asan-coverage=3: instrument all blocks and critical edges.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217098 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-03 22:37:37 +00:00
Kostya Serebryany
891198b358 [asan] Assign a low branch weight to ASan's slow path, patch by Jonas Wagner. This speeds up asan (at least on SPEC) by 1%-5% or more. Also fix lint in dfsan.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216972 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-02 21:46:51 +00:00
Yuri Gorshenin
861eddb266 [asan-assembly-instrumentation] Prologue and epilogue are moved out from InstrumentMemOperand().
Reviewers: eugenis

Subscribers: llvm-commits

Differential revision: http://reviews.llvm.org/D4923

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216879 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-01 12:51:00 +00:00
Yuri Gorshenin
c642ad9546 Revert "[asan-assembly-instrumentation] Prologue and epilogue are moved out from InstrumentMemOperand()."
This reverts commit 895aa39703.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216872 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-01 10:24:04 +00:00
Yuri Gorshenin
895aa39703 [asan-assembly-instrumentation] Prologue and epilogue are moved out from InstrumentMemOperand().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216869 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-01 09:56:45 +00:00
Peter Collingbourne
f5377021c5 [dfsan] Fix non-determinism bug in non-zero label check annotator.
We now use a std::vector instead of a DenseSet to store the list of
label checks so that we can iterate over it deterministically.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216255 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-22 01:18:18 +00:00
Peter Collingbourne
b3b125aafc [dfsan] Treat vararg custom functions like unimplemented functions.
Because declarations of these functions can appear in places like autoconf
checks, they have to be handled somehow, even though we do not support
vararg custom functions. We do so by printing a warning and calling the
uninstrumented function, as we do for unimplemented functions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216042 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-20 01:40:23 +00:00
Chandler Carruth
5e5aa9438d Revert r215415 which causse MSan to crash on a great deal of C++ code.
I've followed up on the original commit as well.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215532 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-13 09:19:39 +00:00
Reid Kleckner
23761603fe msan: Handle musttail calls
First, avoid calling setTailCall(false) on musttail calls.  The funciton
prototypes should be "congruent", so the shadow layout should be exactly
the same.

Second, avoid inserting instrumentation after a musttail call to
propagate the return value shadow.  We don't need to propagate the
result of a tail call, it should already be in the right place.

Reviewed By: eugenis

Differential Revision: http://reviews.llvm.org/D4331

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215415 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-12 00:12:43 +00:00
Peter Collingbourne
95d1d442c9 [dfsan] Try not to create too many additional basic blocks in functions which
already have a large number of blocks. Works around a performance issue with
the greedy register allocator.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214944 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-06 00:33:40 +00:00
Alexey Samsonov
cbd84586ef [ASan] Use metadata to pass source-level information from Clang to ASan.
Instead of creating global variables for source locations and global names,
just create metadata nodes and strings. They will be transformed into actual
globals in the instrumentation pass (if necessary). This approach is more
flexible:
1) we don't have to ensure that our custom globals survive all the optimizations
2) if globals are discarded for some reason, we will simply ignore metadata for them
   and won't have to erase corresponding globals
3) metadata for source locations can be reused for other purposes: e.g. we may
   attach source location metadata to alloca instructions and provide better descriptions
   for stack variables in ASan error reports.

No functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214604 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-02 00:35:50 +00:00
Peter Collingbourne
f1499548d0 [dfsan] Correctly handle loads and stores of zero size.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214561 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-01 21:18:18 +00:00
Evgeniy Stepanov
7ee4f09c94 [msan] Fix handling of array types.
Switch array type shadow from a single integer to
an array of integers (i.e. make it per-element).
This simplifies instrumentation of extractvalue and fixes PR20493.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214398 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-31 11:02:27 +00:00
Evgeniy Stepanov
8a78bb9836 [asan] Support x86 REP MOVS asm instrumentation.
Patch by Yuri Gorshenin.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214395 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-31 09:11:04 +00:00
Alexey Samsonov
30ea42931a [ASan] Don't instrument load/stores with !nosanitize metadata.
This is used to avoid instrumentation of instructions added by UBSan
in Clang frontend (see r213291). This fixes PR20085.

Reviewed in http://reviews.llvm.org/D4544.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213292 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 18:48:12 +00:00
Evgeniy Stepanov
e1287f556f [msan] Avoid redundant origin stores.
Origin is meaningless for fully initialized values. Avoid
storing origin for function arguments that are known to
be always initialized (i.e. shadow is a compile-time null
constant).

This is not about correctness, but purely an optimization.
Seems to affect compilation time of blacklisted functions
significantly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213239 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-17 09:10:37 +00:00
Alexey Samsonov
5c3e016576 CHECK-LABEL-ize one test
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213177 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-16 18:11:31 +00:00
Peter Collingbourne
110748bbb4 [dfsan] Introduce further optimization to reduce the number of union queries.
Specifically, do not compute a union if it is statically known that one
shadow set subsumes the other.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213100 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-15 22:13:19 +00:00
Peter Collingbourne
f32aa7addc [dfsan] Introduce an optimization to reduce the number of union queries.
Specifically, when building a union query, if we are dominated by an identical
query then use the result of that query instead.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213047 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-15 04:41:17 +00:00
Alexey Samsonov
b2d259060d [ASan] Collect unmangled names of global variables in Clang to print them in error reports.
Currently ASan instrumentation pass creates a string with global name
for each instrumented global (to include global names in the error report). Global
name is already mangled at this point, and we may not be able to demangle it
at runtime (e.g. there is no __cxa_demangle on Android).

Instead, create a string with fully qualified global name in Clang, and pass it
to ASan instrumentation pass in llvm.asan.globals metadata. If there is no metadata
for some global, ASan will use the original algorithm.

This fixes https://code.google.com/p/address-sanitizer/issues/detail?id=264.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212872 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-12 00:42:52 +00:00
Timur Iskhodzhanov
cc00568a75 Add a test case for r212596
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212828 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-11 16:32:53 +00:00
Peter Collingbourne
706cbb3337 [dfsan] Handle bitcast aliases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212668 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-10 01:30:39 +00:00
Evgeniy Stepanov
5ba71b01d8 [asan] Generate asm instrumentation in MC.
Generate entire ASan asm instrumentation in MC without
relying on runtime helper functions.

Patch by Yuri Gorshenin.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212455 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-07 13:57:37 +00:00
Evgeniy Stepanov
e3bf8ea879 [msan] Fix handling of phi in blacklisted functions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212454 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-07 13:28:31 +00:00
Evgeniy Stepanov
76a2f8d368 [msan] Stop propagating shadow in blacklisted functions.
With this change all values passed through blacklisted functions
become fully initialized. Previous behavior was to initialize all
loads in blacklisted functions, but apply normal shadow propagation
logic for all other operation.

This makes blacklist applicable in a wider range of situations.

It also makes code for blacklisted functions a lot shorter, which
works as yet another workaround for PR17409.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212268 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-03 11:56:30 +00:00
Evgeniy Stepanov
1bb48fa8ab [msan] Add missing attributes in MemorySanitizer tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212267 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-03 11:49:50 +00:00
Alexey Samsonov
1b6333c47e [ASan] Print exact source location of global variables in error reports.
See https://code.google.com/p/address-sanitizer/issues/detail?id=299 for the
original feature request.

Introduce llvm.asan.globals metadata, which Clang (or any other frontend)
may use to report extra information about global variables to ASan
instrumentation pass in the backend. This metadata replaces
llvm.asan.dynamically_initialized_globals that was used to detect init-order
bugs. llvm.asan.globals contains the following data for each global:
  1) source location (file/line/column info);
  2) whether it is dynamically initialized;
  3) whether it is blacklisted (shouldn't be instrumented).

Source location data is then emitted in the binary and can be picked up
by ASan runtime in case it needs to print error report involving some global.
For example:

  0x... is located 4 bytes to the right of global variable 'C::array' defined in '/path/to/file:17:8' (0x...) of size 40

These source locations are printed even if the binary doesn't have any
debug info.

This is an ABI-breaking change. ASan initialization is renamed to
__asan_init_v4(). Pre-built libraries compiled with older Clang will not work
with the fresh runtime.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212188 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-02 16:54:41 +00:00
Reid Kleckner
3b15c970ab msan: Stop stripping the 'tail' modifier off of calls
This probably isn't necessary since msan started to unpoison the return
value shadow memory before all calls.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212061 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-30 20:12:27 +00:00
Adrian Prantl
93b97c9a57 Debug info: split out complex DIVariable address expressions into a
separate MDNode so they can be uniqued via folding set magic. To conserve
space, DIVariable nodes are still variable-length, with the last two
fields being optional.

No functional change.
http://reviews.llvm.org/D3526

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212050 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-30 17:17:35 +00:00
David Majnemer
c8a1169c93 IR: Add COMDATs to the IR
This new IR facility allows us to represent the object-file semantic of
a COMDAT group.

COMDATs allow us to tie together sections and make the inclusion of one
dependent on another. This is required to implement features like MS
ABI VFTables and optimizing away certain kinds of initialization in C++.

This functionality is only representable in COFF and ELF, Mach-O has no
similar mechanism.

Differential Revision: http://reviews.llvm.org/D4178

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211920 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-27 18:19:56 +00:00
Evgeniy Stepanov
6ce4a9f175 [msan] Fix bad interaction between with-calls mode and chained origin tracking.
Origin history should only be recorded for uninitialized values, because it is
meaningless otherwise. This change moves __msan_chain_origin to the runtime
library side and makes it conditional on the corresponding shadow value.

Previous code was correct, but _very_ inefficient.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211700 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-25 14:41:57 +00:00
Evgeniy Stepanov
fc72762a0f [msan] Handle X86 *.psad.* and *.pmadd.* intrinsics.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211156 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-18 12:02:29 +00:00
Evgeniy Stepanov
792a173523 [msan] Fix handling of multiplication by a constant with a number of trailing zeroes.
Multiplication by an integer with a number of trailing zero bits leaves
the same number of lower bits of the result initialized to zero.
This change makes MSan take this into account in the case of multiplication by
a compile-time constant.

We don't handle the general, non-constant, case because
(a) it's not going to be cheap (computation-wise);
(b) multiplication by a partially uninitialized value in user code is
    a bad idea anyway.

Constant case must be handled because it appears from LLVM optimization of a
completely valid user code, as the test case in compiler-rt demonstrates.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211092 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-17 09:23:12 +00:00
Alexey Samsonov
6140939365 Remove top-level Clang -fsanitize= flags for optional ASan features.
Init-order and use-after-return modes can currently be enabled
by runtime flags. use-after-scope mode is not really working at the
moment.

The only problem I see is that users won't be able to disable extra
instrumentation for init-order and use-after-scope by a top-level Clang flag.
But this instrumentation was implicitly enabled for quite a while and
we didn't hear from users hurt by it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210924 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-13 17:53:44 +00:00
Tim Northover
8f2a85e099 IR: add "cmpxchg weak" variant to support permitted failure.
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
2014-06-13 14:24:07 +00:00
Alp Toker
8aeca44558 Reduce verbiage of lit.local.cfg files
We can just split targets_to_build in one place and make it immutable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210496 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-09 22:42:55 +00:00
Evgeniy Stepanov
35d5a437ea Fix test in r210472.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210473 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-09 14:48:53 +00:00