The description of the 'returned' attribute says that it is only used when
code-generating the caller. I'd like to make the optimizer smarter about
looking through functions with returned arguments (generally, but motivated by
my llvm.noalias work). As David pointed out in the review of D22202, the
LangRef should be updated to make its expanded uses clearer.
Differential Revision: http://reviews.llvm.org/D22205
llvm-svn: 275026
Text suggested by Daniel Berlin. While it is likely to be exactly what
the advisory committee would do anyway, codifying it does no harm and
helps reassure people that rare does not mean arbitrary.
Differential Revision: http://reviews.llvm.org/D21981
llvm-svn: 274659
Summary:
This complements the earlier addition of IntrWriteMem and IntrWriteArgMem
LLVM intrinsic properties, see D18291.
Also start using the attribute for memset, memcpy, and memmove intrinsics,
and remove their special-casing in BasicAliasAnalysis.
Reviewers: reames, joker.eph
Subscribers: joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D18714
llvm-svn: 274485
This new chapter describes compiling LLVM IR to object files.
The new chaper is chapter 8, so later chapters have been renumbered.
Since this brings us to 10 chapters total, I've also needed to rename
the other chapters to use two digit numbering.
Differential Revision: http://reviews.llvm.org/D18070
llvm-svn: 274441
associated reporting guide.
I want to emphasize that at this point these are just drafts!
This is the result of very extended discussion on the mailing lists on
several different threads:
http://lists.llvm.org/pipermail/llvm-dev/2015-October/091218.htmlhttp://lists.llvm.org/pipermail/llvm-dev/2016-May/099120.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151019/307070.html
The reporting guide in particular I anticipate will be shaped somewhat
by the advisory committee when they are selected. But hopefully this
serves as a good starting point and good guidance while the advisory
committee is being sorted out.
I'd like to thank all the folks who contributed to this. Many, *many*
people worked to help with drafting, wording, suggestions, and edits.
Also, this is based on widely used existing codes of coduct as mentioned
in the text, and the original authors of those deserve many thanks as
well.
Differential Revision: http://reviews.llvm.org/D13741
llvm-svn: 274268
This is a resubmittion of 263158 change after fixing the existing problem with intrinsics mangling (see LTO and intrinsics mangling llvm-dev thread for details).
This patch fixes the problem which occurs when loop-vectorize tries to use @llvm.masked.load/store intrinsic for a non-default addrspace pointer. It fails with "Calling a function with a bad signature!" assertion in CallInst constructor because it tries to pass a non-default addrspace pointer to the pointer argument which has default addrspace.
The fix is to add pointer type as another overloaded type to @llvm.masked.load/store intrinsics.
Reviewed By: reames
Differential Revision: http://reviews.llvm.org/D17270
llvm-svn: 274043
Passing -output-dir path/to/dir to llvm-cov show creates path/to/dir if
it doesn't already exist, and prints reports into that directory.
In function view mode, all views are written into
path/to/dir/functions.$EXTENSION. In file view mode, all views are
written into path/to/dir/coverage/$PATH.$EXTENSION.
Changes since the initial commit:
- Avoid accidentally closing stdout twice.
llvm-svn: 273985
This reverts commit r273971. test/profile/instrprof-visibility.cpp is
failing because of an uncaught error in SafelyCloseFileDescriptor.
llvm-svn: 273978
Passing -output-dir path/to/dir to llvm-cov show creates path/to/dir if
it doesn't already exist, and prints reports into that directory.
In function view mode, all views are written into
path/to/dir/functions.$EXTENSION. In file view mode, all views are
written into path/to/dir/coverage/$PATH.$EXTENSION.
llvm-svn: 273971
This is a resubmittion of 263158 change after fixing the existing problem with intrinsics mangling (see LTO and intrinsics mangling llvm-dev thread for details).
This patch fixes the problem which occurs when loop-vectorize tries to use @llvm.masked.load/store intrinsic for a non-default addrspace pointer. It fails with "Calling a function with a bad signature!" assertion in CallInst constructor because it tries to pass a non-default addrspace pointer to the pointer argument which has default addrspace.
The fix is to add pointer type as another overloaded type to @llvm.masked.load/store intrinsics.
Reviewed By: reames
Differential Revision: http://reviews.llvm.org/D17270
llvm-svn: 273892
This intrinsic safely loads a function pointer from a virtual table pointer
using type metadata. This intrinsic is used to implement control flow integrity
in conjunction with virtual call optimization. The virtual call optimization
pass will optimize away llvm.type.checked.load intrinsics associated with
devirtualized calls, thereby removing the type check in cases where it is
not needed to enforce the control flow integrity constraint.
This patch also introduces the capability to copy type metadata between
global variables, and teaches the virtual call optimization pass to do so.
Differential Revision: http://reviews.llvm.org/D21121
llvm-svn: 273756
The bitset metadata currently used in LLVM has a few problems:
1. It has the wrong name. The name "bitset" refers to an implementation
detail of one use of the metadata (i.e. its original use case, CFI).
This makes it harder to understand, as the name makes no sense in the
context of virtual call optimization.
2. It is represented using a global named metadata node, rather than
being directly associated with a global. This makes it harder to
manipulate the metadata when rebuilding global variables, summarise it
as part of ThinLTO and drop unused metadata when associated globals are
dropped. For this reason, CFI does not currently work correctly when
both CFI and vcall opt are enabled, as vcall opt needs to rebuild vtable
globals, and fails to associate metadata with the rebuilt globals. As I
understand it, the same problem could also affect ASan, which rebuilds
globals with a red zone.
This patch solves both of those problems in the following way:
1. Rename the metadata to "type metadata". This new name reflects how
the metadata is currently being used (i.e. to represent type information
for CFI and vtable opt). The new name is reflected in the name for the
associated intrinsic (llvm.type.test) and pass (LowerTypeTests).
2. Attach metadata directly to the globals that it pertains to, rather
than using the "llvm.bitsets" global metadata node as we are doing now.
This is done using the newly introduced capability to attach
metadata to global variables (r271348 and r271358).
See also: http://lists.llvm.org/pipermail/llvm-dev/2016-June/100462.html
Differential Revision: http://reviews.llvm.org/D21053
llvm-svn: 273729
Summary:
We will start generating this in a future patch.
Reviewers: arsenm, kzhuravl, rafael, ruiu, tony-tye
Subscribers: arsenm, llvm-commits, kzhuravl
Differential Revision: http://reviews.llvm.org/D21482
llvm-svn: 273628
This change is motivated by an upcoming change to the metadata representation
used for CFI. The indirect function call checker needs type information for
external function declarations in order to correctly generate jump table
entries for such declarations. We currently associate such type information
with declarations using a global metadata node, but I plan [1] to move all
such metadata to global object attachments.
In bitcode, metadata attachments for function declarations appear in the
global metadata block. This seems reasonable to me because I expect metadata
attachments on declarations to be uncommon. In the long term I'd also expect
this to be the case for CFI, because we'd want to use some specialized bitcode
format for this metadata that could be read as part of the ThinLTO thin-link
phase, which would mean that it would not appear in the global metadata block.
To solve the lazy loaded metadata issue I was seeing with D20147, I use the
same bitcode representation for metadata attachments for global variables as I
do for function declarations. Since there's a use case for metadata attachments
in the global metadata block, we might as well use that representation for
global variables as well, at least until we have a mechanism for lazy loading
global variables.
In the assembly format, the metadata attachments appear after the "declare"
keyword in order to avoid a parsing ambiguity.
[1] http://lists.llvm.org/pipermail/llvm-dev/2016-June/100462.html
Differential Revision: http://reviews.llvm.org/D21052
llvm-svn: 273336
Nearly all the changes to this pass have been done while maintaining and
updating other parts of LLVM. LLVM has had another pass, SROA, which
has superseded ScalarReplAggregates for quite some time.
Differential Revision: http://reviews.llvm.org/D21316
llvm-svn: 272737
If a local_unnamed_addr attribute is attached to a global, the address
is known to be insignificant within the module. It is distinct from the
existing unnamed_addr attribute in that it only describes a local property
of the module rather than a global property of the symbol.
This attribute is intended to be used by the code generator and LTO to allow
the linker to decide whether the global needs to be in the symbol table. It is
possible to exclude a global from the symbol table if three things are true:
- This attribute is present on every instance of the global (which means that
the normal rule that the global must have a unique address can be broken without
being observable by the program by performing comparisons against the global's
address)
- The global has linkonce_odr linkage (which means that each linkage unit must have
its own copy of the global if it requires one, and the copy in each linkage unit
must be the same)
- It is a constant or a function (which means that the program cannot observe that
the unique-address rule has been broken by writing to the global)
Although this attribute could in principle be computed from the module
contents, LTO clients (i.e. linkers) will normally need to be able to compute
this property as part of symbol resolution, and it would be inefficient to
materialize every module just to compute it.
See:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20160509/356401.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20160516/356738.html
for earlier discussion.
Part of the fix for PR27553.
Differential Revision: http://reviews.llvm.org/D20348
llvm-svn: 272709
This enables use of the 'R' and 'T' memory constraints for inline ASM
operands on SystemZ, which allow an index register as well as an
immediate displacement. This patch includes corresponding documentation
and test case updates.
As with the last patch of this kind, I moved the 'm' constraint to the
most general case, which is now 'T' (base + 20-bit signed displacement +
index register).
Author: colpell
Differential Revision: http://reviews.llvm.org/D21239
llvm-svn: 272547
Summary: This also deprecated the get attribute function familly.
Reviewers: Wallbraker, whitequark, joker.eph, echristo, rafael, jyknight
Subscribers: axw, joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D19181
llvm-svn: 272504
Summary:
This documents the various relocation types that are supported by the
Radeon Open Compute (ROC) runtime (which is essentially the dynamic
linker for AMDGPU).
Only R_AMDGPU_32 is not currently supported by the ROC runtime, but
it will usually be resolved at link time by lld.
Patch by: Konstantin Zhuravlyov
Reviewers: kzhuravl, rafael
Subscribers: rafael, arsenm, llvm-commits, kzhuravl
Differential Revision: http://reviews.llvm.org/D20952
llvm-svn: 272352
This enables use of the 'S' constraint for inline ASM operands on
SystemZ, which allows for a memory reference with a signed 20-bit
immediate displacement. This patch includes corresponding documentation
and test case updates.
I've changed the 'T' constraint to match the new behavior for 'S', as
'T' also uses a long displacement (though index constraints are still
not implemented). I also changed 'm' to match the behavior for 'S' as
this will allow for a wider range of displacements for 'm', though
correct me if that's not the right decision.
Author: colpell
Differential Revision: http://reviews.llvm.org/D21097
llvm-svn: 272266
Changes since the initial commit:
- Use echo instead of printf. This should side-step the character
escaping issues on Windows.
Differential Revision: http://reviews.llvm.org/D20980
llvm-svn: 272068
take into account modernizations in r246002 and r270381.
Patch based on http://reviews.llvm.org/D20954 by Miroslav Hrncir.
Thanks Miroslav!
llvm-svn: 271985
Summary:
This is an initial implementation of a Hardened Allocator based on Sanitizer Common's CombinedAllocator.
It aims at mitigating heap based vulnerabilities by adding several features to the base allocator, while staying relatively fast.
The following were implemented:
- additional consistency checks on the allocation function parameters and on the heap chunks;
- use of checksum protected chunk header, to detect corruption;
- randomness to the allocator base;
- delayed freelist (quarantine), to mitigate use after free and overall determinism.
Additional mitigations are in the works.
Reviewers: eugenis, aizatsky, pcc, krasin, vitalybuka, glider, dvyukov, kcc
Subscribers: kubabrecka, filcab, llvm-commits
Differential Revision: http://reviews.llvm.org/D20084
llvm-svn: 271968
Hal Finkel