Commit Graph

557 Commits

Author SHA1 Message Date
Pete Cooper 125ad17fed Use foreach loop over constant operands. NFC.
A number of places had explicit loops over Constant::operands().
Just use foreach loops where possible.

llvm-svn: 240694
2015-06-25 20:51:38 +00:00
Alexander Kornienko f00654e31b Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)
Apparently, the style needs to be agreed upon first.

llvm-svn: 240390
2015-06-23 09:49:53 +00:00
Alexander Kornienko 70bc5f1398 Fixed/added namespace ending comments using clang-tidy. NFC
The patch is generated using this command:

tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
  -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
  llvm/lib/


Thanks to Eugene Kosov for the original patch!

llvm-svn: 240137
2015-06-19 15:57:42 +00:00
Benjamin Kramer 5014f40fa6 [Bitcode] Replace hand-coded little endian handling with Endian.h functions.
No functional change intended.

llvm-svn: 239944
2015-06-17 20:55:30 +00:00
David Majnemer 7fddeccb8b Move the personality function from LandingPadInst to Function
The personality routine currently lives in the LandingPadInst.

This isn't desirable because:
- All LandingPadInsts in the same function must have the same
  personality routine.  This means that each LandingPadInst beyond the
  first has an operand which produces no additional information.

- There is ongoing work to introduce EH IR constructs other than
  LandingPadInst.  Moving the personality routine off of any one
  particular Instruction and onto the parent function seems a lot better
  than have N different places a personality function can sneak onto an
  exceptional function.

Differential Revision: http://reviews.llvm.org/D10429

llvm-svn: 239940
2015-06-17 20:52:32 +00:00
Duncan P. N. Exon Smith 51149d5589 modules: Add explicit dependency on intrinsics_gen
`LLVM_ENABLE_MODULES` builds sometimes fail because `Intrinsics.td`
needs to regenerate `Instrinsics.h` before anyone can include anything
from the LLVM_IR module.  Represent the dependency explicitly to prevent
that.

llvm-svn: 239796
2015-06-16 00:44:12 +00:00
Peter Collingbourne 82437bf7a5 Protection against stack-based memory corruption errors using SafeStack
This patch adds the safe stack instrumentation pass to LLVM, which separates
the program stack into a safe stack, which stores return addresses, register
spills, and local variables that are statically verified to be accessed
in a safe way, and the unsafe stack, which stores everything else. Such
separation makes it much harder for an attacker to corrupt objects on the
safe stack, including function pointers stored in spilled registers and
return addresses. You can find more information about the safe stack, as
well as other parts of or control-flow hijack protection technique in our
OSDI paper on code-pointer integrity (http://dslab.epfl.ch/pubs/cpi.pdf)
and our project website (http://levee.epfl.ch).

The overhead of our implementation of the safe stack is very close to zero
(0.01% on the Phoronix benchmarks). This is lower than the overhead of
stack cookies, which are supported by LLVM and are commonly used today,
yet the security guarantees of the safe stack are strictly stronger than
stack cookies. In some cases, the safe stack improves performance due to
better cache locality.

Our current implementation of the safe stack is stable and robust, we
used it to recompile multiple projects on Linux including Chromium, and
we also recompiled the entire FreeBSD user-space system and more than 100
packages. We ran unit tests on the FreeBSD system and many of the packages
and observed no errors caused by the safe stack. The safe stack is also fully
binary compatible with non-instrumented code and can be applied to parts of
a program selectively.

This patch is our implementation of the safe stack on top of LLVM. The
patches make the following changes:

- Add the safestack function attribute, similar to the ssp, sspstrong and
  sspreq attributes.

- Add the SafeStack instrumentation pass that applies the safe stack to all
  functions that have the safestack attribute. This pass moves all unsafe local
  variables to the unsafe stack with a separate stack pointer, whereas all
  safe variables remain on the regular stack that is managed by LLVM as usual.

- Invoke the pass as the last stage before code generation (at the same time
  the existing cookie-based stack protector pass is invoked).

- Add unit tests for the safe stack.

Original patch by Volodymyr Kuznetsov and others at the Dependable Systems
Lab at EPFL; updates and upstreaming by myself.

Differential Revision: http://reviews.llvm.org/D6094

llvm-svn: 239761
2015-06-15 21:07:11 +00:00
Yaron Keren 4c20debe3c Rangify several for loops in ValueEnumerator constructor.
llvm-svn: 239636
2015-06-12 20:18:20 +00:00
Owen Anderson 85fa7d5037 Add initial support for the convergent attribute.
llvm-svn: 238264
2015-05-26 23:48:40 +00:00
Adrian Prantl 1f599f9f65 IR / debug info: Add a DWOId field to DICompileUnit,
so DWARF skeleton CUs can be expression in IR. A skeleton CU is a
(typically empty) DW_TAG_compile_unit that has a DW_AT_(GNU)_dwo_name and
a DW_AT_(GNU)_dwo_id attribute. It is used to refer to external debug info.

This is a prerequisite for clang module debugging as discussed in
http://lists.cs.uiuc.edu/pipermail/cfe-dev/2014-November/040076.html.
In order to refer to external types stored in split DWARF (dwo) objects,
such as clang modules, we need to emit skeleton CUs, which identify the
dwarf object (i.e., the clang module) by filename (the SplitDebugFilename)
and a hash value, the dwo_id.

This patch only contains the IR changes. The idea is that a CUs with a
non-zero dwo_id field will be emitted together with a DW_AT_GNU_dwo_name
and DW_AT_GNU_dwo_id attribute.

http://reviews.llvm.org/D9488
rdar://problem/20091852

llvm-svn: 237949
2015-05-21 20:37:30 +00:00
Duncan P. N. Exon Smith 538ef562bd Bitcode: Set LastDL after writing DebugLocs
Somehow I dropped this in r233585, and we haven't had `DEBUG_LOC_AGAIN`
records since.  Add it back.  Also tests that the output assembly looks
okay.

Fixes PR23436.

llvm-svn: 236661
2015-05-06 22:51:12 +00:00
Duncan P. N. Exon Smith a9308c49ef IR: Give 'DI' prefix to debug info metadata
Finish off PR23080 by renaming the debug info IR constructs from `MD*`
to `DI*`.  The last of the `DIDescriptor` classes were deleted in
r235356, and the last of the related typedefs removed in r235413, so
this has all baked for about a week.

Note: If you have out-of-tree code (like a frontend), I recommend that
you get everything compiling and tests passing with the *previous*
commit before updating to this one.  It'll be easier to keep track of
what code is using the `DIDescriptor` hierarchy and what you've already
updated, and I think you're extremely unlikely to insert bugs.  YMMV of
course.

Back to *this* commit: I did this using the rename-md-di-nodes.sh
upgrade script I've attached to PR23080 (both code and testcases) and
filtered through clang-format-diff.py.  I edited the tests for
test/Assembler/invalid-generic-debug-node-*.ll by hand since the columns
were off-by-three.  It should work on your out-of-tree testcases (and
code, if you've followed the advice in the previous paragraph).

Some of the tests are in badly named files now (e.g.,
test/Assembler/invalid-mdcompositetype-missing-tag.ll should be
'dicompositetype'); I'll come back and move the files in a follow-up
commit.

llvm-svn: 236120
2015-04-29 16:38:44 +00:00
David Blaikie bdb4910202 [opaque pointer type] Encode the allocated type of an alloca rather than its pointer result type.
llvm-svn: 235998
2015-04-28 16:51:01 +00:00
David Blaikie 2a661cd062 [opaque pointer type] Encode the pointee type in the bitcode for 'cmpxchg'
As a space optimization, this instruction would just encode the pointer
type of the first operand and use the knowledge that the second and
third operands would be of the pointee type of the first. When typed
pointers go away, this assumption will no longer be available - so
encode the type of the second operand explicitly and rely on that for
the third.

Test case added to demonstrate the backwards compatibility concern,
which only comes up when the definition of the second operand comes
after the use (hence the weird basic block sequence) - at which point
the type needs to be explicitly encoded in the bitcode and the record
length changes to accommodate this.

llvm-svn: 235966
2015-04-28 04:30:29 +00:00
David Blaikie 1a848da518 [opaque pointer type] encode the pointee type of global variables
Use a few extra bits in the const field (after widening it from a fixed
single bit) to stash the address space which is no longer provided by
the type (and an extra bit in there to specify that we're using that new
encoding).

llvm-svn: 235911
2015-04-27 19:58:56 +00:00
Duncan P. N. Exon Smith 3d4cd756b6 IR: Add assembly/bitcode support for function metadata attachments
Add serialization support for function metadata attachments (added in
r235783).  The syntax is:

    define @foo() !attach !0 {

Metadata attachments are only allowed on functions with bodies.  Since
they come before the `{`, they're not really part of the body; since
they require a body, they're not really part of the header.  In
`LLParser` I gave them a separate function called from `ParseDefine()`,
`ParseOptionalFunctionMetadata()`.

In bitcode, I'm using the same `METADATA_ATTACHMENT` record used by
instructions.  Instruction metadata attachments are included in a
special "attachment" block at the end of a `Function`.  The attachment
records are laid out like this:

    InstID (KindID MetadataID)+

Note that these records always have an odd number of fields.  The new
code takes advantage of this to recognize function attachments (which
don't need an instruction ID):

    (KindID MetadataID)+

This means we can use the same attachment block already used for
instructions.

This is part of PR23340.

llvm-svn: 235785
2015-04-24 22:04:41 +00:00
David Blaikie 5ea1f7b744 [opaque pointer type] bitcode: add explicit callee type to invoke instructions
llvm-svn: 235735
2015-04-24 18:06:06 +00:00
David Blaikie 612ddbfde0 [opaque pointer types] Serialize the value type for store instructions
Without pointee types the space optimization of storing only the pointer
type and not the value type won't be viable - so add the extra type
information that would be missing.

Storeatomic coming soon.

llvm-svn: 235474
2015-04-22 04:14:42 +00:00
David Blaikie 561a157233 [opaque pointer type] Serialize the type of an llvm::Function as a function type rather than a function pointer type
llvm-svn: 235200
2015-04-17 16:28:26 +00:00
David Blaikie dbe6e0f171 [opaque pointer type] Explicit pointee type for call instruction
Use an extra bit in the CCInfo to flag the newer version of the
instructiont hat includes the type explicitly.

Tested the newer error cases I added, but didn't add tests for the finer
granularity improvements to existing error paths.

llvm-svn: 235160
2015-04-17 06:40:14 +00:00
Sanjoy Das 31ea6d1590 [IR] Introduce a dereferenceable_or_null(N) attribute.
Summary:
If a pointer is marked as dereferenceable_or_null(N), LLVM assumes it
is either `null` or `dereferenceable(N)` or both.  This change only
introduces the attribute and adds a token test case for the `llvm-as`
/ `llvm-dis`.  It does not hook up other parts of the optimizer to
actually exploit the attribute -- those changes will come later.

For pointers in address space 0, `dereferenceable(N)` is now exactly
equivalent to `dereferenceable_or_null(N)` && `nonnull`.  For other
address spaces, `dereferenceable(N)` is potentially weaker than
`dereferenceable_or_null(N)` && `nonnull` (since we could have a null
`dereferenceable(N)` pointer).

The motivating case for this change is Java (and other managed
languages), where pointers are either `null` or dereferenceable up to
some usually known-at-compile-time constant offset.

Reviewers: rafael, hfinkel

Reviewed By: hfinkel

Subscribers: nicholas, llvm-commits

Differential Revision: http://reviews.llvm.org/D8650

llvm-svn: 235132
2015-04-16 20:29:50 +00:00
Duncan P. N. Exon Smith 62e0f454a0 DebugInfo: Remove 'inlinedAt:' field from MDLocalVariable
Remove 'inlinedAt:' from MDLocalVariable.  Besides saving some memory
(variables with it seem to be single largest `Metadata` contributer to
memory usage right now in -g -flto builds), this stops optimization and
backend passes from having to change local variables.

The 'inlinedAt:' field was used by the backend in two ways:

 1. To tell the backend whether and into what a variable was inlined.
 2. To create a unique id for each inlined variable.

Instead, rely on the 'inlinedAt:' field of the intrinsic's `!dbg`
attachment, and change the DWARF backend to use a typedef called
`InlinedVariable` which is `std::pair<MDLocalVariable*, MDLocation*>`.
This `DebugLoc` is already passed reliably through the backend (as
verified by r234021).

This commit removes the check from r234021, but I added a new check
(that will survive) in r235048, and changed the `DIBuilder` API in
r235041 to require a `!dbg` attachment whose 'scope:` is in the same
`MDSubprogram` as the variable's.

If this breaks your out-of-tree testcases, perhaps the script I used
(mdlocalvariable-drop-inlinedat.sh) will help; I'll attach it to PR22778
in a moment.

llvm-svn: 235050
2015-04-15 22:29:27 +00:00
Duncan P. N. Exon Smith 8a7b84b4d0 uselistorder: Remove the global bits
Remove all the global bits to do with preserving use-list order by
moving the `cl::opt`s to the individual tools that want them.  There's a
minor functionality change to `libLTO`, in that you can't send in
`-preserve-bc-uselistorder=false`, but making that bit settable (if it's
worth doing) should be through explicit LTO API.

As a drive-by fix, I removed some includes of `UseListOrder.h` that were
made unnecessary by recent commits.

llvm-svn: 234973
2015-04-15 03:14:06 +00:00
Duncan P. N. Exon Smith 679db3345c uselistorder: Pull bit through BitcodeWriterPass
Now the callers of `BitcodeWriterPass` decide whether or not to preserve
bitcode use-list order.

llvm-svn: 234959
2015-04-15 00:34:24 +00:00
Duncan P. N. Exon Smith a052ed6381 uselistorder: Pull the bit through WriteToBitcodFile()
Change the callers of `WriteToBitcodeFile()` to pass `true` or
`shouldPreserveBitcodeUseListOrder()` explicitly.  I left the callers
that want to send `false` alone.

I'll keep pushing the bit higher until hopefully I can delete the global
`cl::opt` entirely.

llvm-svn: 234957
2015-04-15 00:10:50 +00:00
Duncan P. N. Exon Smith 458593a457 uselistorder: Thread bit through ValueEnumerator
Canonicalize access to whether to preserve use-list order in bitcode on
a `bool` stored in `ValueEnumerator`.  Next step, expose this as a
`bool` through `WriteBitcodeToFile()`.

llvm-svn: 234956
2015-04-14 23:45:11 +00:00
Duncan P. N. Exon Smith 7ad0bd54d3 DebugInfo: Make MDSubprogram::getFunction() return Constant
Change `MDSubprogram::getFunction()` and
`MDGlobalVariable::getConstant()` to return a `Constant`.  Previously,
both returned `ConstantAsMetadata`.

llvm-svn: 234699
2015-04-11 20:27:40 +00:00
Duncan P. N. Exon Smith 1134473f51 IR: Remove MDTupleTypedArrayWrapper::operator MDTuple*()
Remove `MDTupleTypedArrayWrapper::operator MDTuple*()`, since it causes
ambiguity (at least in some [1] compilers [2]) when using indexes to
`MDTupleTypedArrayWrapper::operator[](unsigned)` that are convertible to
(but not the same as) `unsigned`.

[1]: http://lab.llvm.org:8011/builders/sanitizer-windows/builds/2308
[2]: http://lab.llvm.org:8011/builders/clang-cmake-mips/builds/4442

llvm-svn: 234326
2015-04-07 16:50:39 +00:00
Duncan P. N. Exon Smith 5dcf621c8a IR: Rename MDSubrange::getLo() to getLowerBound()
During initial review, the `lo:` field was renamed to `lowerBound:`.
Make the same change to the C++ API.

llvm-svn: 234267
2015-04-07 00:39:59 +00:00
Duncan P. N. Exon Smith ab659fb3d0 IR: Use the new DebugLoc API, NFC
Update lib/IR and lib/Bitcode to use the new `DebugLoc` API.  Added an
explicit conversion to `bool` (avoiding a conversion to `MDLocation`),
since a couple of these use cases need to handle broken code.

llvm-svn: 233585
2015-03-30 19:40:05 +00:00
Duncan P. N. Exon Smith 1facf7a13d Bitcode: Reflow code to use early continues, NFC
llvm-svn: 233578
2015-03-30 18:29:18 +00:00
Duncan P. N. Exon Smith 79f8d11d5a AsmWriter: Assert on unresolved metadata nodes
Assert that `MDNode::isResolved()`.  While in theory the `Verifier`
should catch this, it doesn't descend into all debug info, and the
`DebugInfoVerifier` doesn't call into the `Verifier`.  Besides, this
helps to catch bugs when `-disable-verify=true`.

Note that I haven't come across a place where this fails with clang
today, so no testcase.

llvm-svn: 232442
2015-03-17 00:16:35 +00:00
David Blaikie b9263570a5 [opaque pointer type] Bitcode support for explicit type parameter on the gep operator
This happened to be fairly easy to support backwards compatibility based
on the number of operands (old format had an even number, new format has
one more operand so an odd number).

test/Bitcode/old-aliases.ll already appears to test old gep operators
(if I remove the backwards compatibility in the BitcodeReader, this and
another test fail) so I'm not adding extra test coverage here.

llvm-svn: 232216
2015-03-13 21:03:36 +00:00
David Blaikie b5b5efd2d1 [opaque pointer type] Bitcode support for explicit type parameter on GEP.
Like r230414, add bitcode support including backwards compatibility, for
an explicit type parameter to GEP.

At the suggestion of Duncan I tried coalescing the two older bitcodes into a
single new bitcode, though I did hit a wrinkle: I couldn't figure out how to
create an explicit abbreviation for a record with a variable number of
arguments (the indicies to the gep). This means the discriminator between
inbounds and non-inbounds gep is a full variable-length field I believe? Is my
understanding correct? Is there a way to create such an abbreviation? Should I
just use two bitcodes as before?

Reviewers: dexonsmith

Differential Revision: http://reviews.llvm.org/D7736

llvm-svn: 230415
2015-02-25 01:08:52 +00:00
David Blaikie 8503565eec [opaque pointer type] bitcode support for explicit type parameter to the load instruction
Summary:
I've taken my best guess at this, but I've cargo culted in places & so
explanations/corrections would be great.

This seems to pass all the tests (check-all, covering clang and llvm) so I
believe that pretty well exercises both the backwards compatibility and common
(same version) compatibility given the number of checked in bitcode files we
already have. Is that a reasonable approach to testing here? Would some more
explicit tests be desired?

1) is this the right way to do back-compat in this case (looking at the number
  of entries in the bitcode record to disambiguate between the old schema and
  the new?)

2) I don't quite understand the logarithm logic to choose the encoding type of
  the type parameter in the abbreviation description, but I found another
  instruction doing the same thing & it seems to work. Is that the right
  approach?

Reviewers: dexonsmith

Differential Revision: http://reviews.llvm.org/D7655

llvm-svn: 230414
2015-02-25 01:07:20 +00:00
David Blaikie 7b0281089e BitcodeWriter: Refactor common computation of bits required for a type index.
Suggested by Duncan. Happy to bikeshed the name, cache the result, etc.

llvm-svn: 230410
2015-02-25 00:51:52 +00:00
Duncan P. N. Exon Smith ad6eb127c9 Bitcode: Stop assuming non-null fields
When writing the bitcode serialization for the new debug info hierarchy,
I assumed two fields would never be null.

Drop that assumption, since it's brittle (and crashes the
`BitcodeWriter` if wrong), and is a check better left for the verifier
anyway.  (No need for a bitcode upgrade here, since the new hierarchy is
still not in place.)

The fields in question are `MDCompileUnit::getFile()` and
`MDDerivedType::getBaseType()`, the latter of which isn't null in
test/Transforms/Mem2Reg/ConvertDebugInfo2.ll (see !14, a pointer to
nothing).  While the testcase might have bitrotted, there's no reason
for the bitcode format to rely on non-null for metadata operands.

This also fixes a bug in `AsmWriter` where if the `file:` is null it
isn't emitted (caught by the double-round trip in the testcase I'm
adding) -- this is a required field in `LLParser`.

I'll circle back to ConvertDebugInfo2.  Once the specialized nodes are
in place, I'll be trying to turn the debug info verifier back on by
default (in the newer module pass form committed r206300) and throwing
more logic in there.  If the testcase has bitrotted (as opposed to me
not understanding the schema correctly) I'll fix it then.

llvm-svn: 229960
2015-02-20 03:17:58 +00:00
Duncan P. N. Exon Smith 3d62bbacb1 IR: Drop scope from MDTemplateParameter
Follow-up to r229740, which removed `DITemplate*::getContext()` after my
upgrade script revealed that scopes are always `nullptr` for template
parameters.  This is the other shoe: drop `scope:` from
`MDTemplateParameter` and its two subclasses.  (Note: a bitcode upgrade
would be pointless, since the hierarchy hasn't been moved into place.)

llvm-svn: 229791
2015-02-19 00:37:21 +00:00
Benjamin Kramer 6cd780ff21 Prefer SmallVector::append/insert over push_back loops.
Same functionality, but hoists the vector growth out of the loop.

llvm-svn: 229500
2015-02-17 15:29:18 +00:00
Aaron Ballman f9a1897c72 Removing LLVM_DELETED_FUNCTION, as MSVC 2012 was the last reason for requiring the macro. NFC; LLVM edition.
llvm-svn: 229340
2015-02-15 22:54:22 +00:00
Duncan P. N. Exon Smith 1c93116489 AsmWriter/Bitcode: MDImportedEntity
llvm-svn: 229025
2015-02-13 01:46:02 +00:00
Duncan P. N. Exon Smith d45ce96c38 AsmWriter/Bitcode: MDObjCProperty
llvm-svn: 229024
2015-02-13 01:43:22 +00:00
Duncan P. N. Exon Smith 0c5c0124ac AsmWriter/Bitcode: MDExpression
llvm-svn: 229023
2015-02-13 01:42:09 +00:00
Duncan P. N. Exon Smith 72fe2d0b79 AsmWriter/Bitcode: MDLocalVariable
llvm-svn: 229022
2015-02-13 01:39:44 +00:00
Duncan P. N. Exon Smith c8f810a017 AsmWriter/Bitcode: MDGlobalVariable
llvm-svn: 229020
2015-02-13 01:35:40 +00:00
Duncan P. N. Exon Smith 2847f3805e AsmWriter/Bitcode: MDTemplate{Type,Value}Parameter
llvm-svn: 229019
2015-02-13 01:34:32 +00:00
Duncan P. N. Exon Smith e146000565 AsmWriter/Bitcode: MDNamespace
llvm-svn: 229018
2015-02-13 01:32:09 +00:00
Duncan P. N. Exon Smith 06a0702e40 AsmWriter/Bitcode: MDLexicalBlockFile
llvm-svn: 229017
2015-02-13 01:30:42 +00:00
Duncan P. N. Exon Smith a96d409997 AsmWriter/Bitcode: MDLexicalBlock
llvm-svn: 229016
2015-02-13 01:29:28 +00:00
Duncan P. N. Exon Smith 19fc5ed7db AsmWriter/Bitcode: MDSubprogram
llvm-svn: 229014
2015-02-13 01:26:47 +00:00