Load Hardening.
Wires up the existing pass to work with a proper IR attribute rather
than just a hidden/internal flag. The internal flag continues to work
for now, but I'll likely remove it soon.
Most of the churn here is adding the IR attribute. I talked about this
Kristof Beyls and he seemed at least initially OK with this direction.
The idea of using a full attribute here is that we *do* expect at least
some forms of this for other architectures. There isn't anything
*inherently* x86-specific about this technique, just that we only have
an implementation for x86 at the moment.
While we could potentially expose this as a Clang-level attribute as
well, that seems like a good question to defer for the moment as it
isn't 100% clear whether that or some other programmer interface (or
both?) would be best. We'll defer the programmer interface side of this
for now, but at least get to the point where the feature can be enabled
without relying on implementation details.
This also allows us to do something that was really hard before: we can
enable *just* the indirect call retpolines when using SLH. For x86, we
don't have any other way to mitigate indirect calls. Other architectures
may take a different approach of course, and none of this is surfaced to
user-level flags.
Differential Revision: https://reviews.llvm.org/D51157
llvm-svn: 341363
Most users won't have to worry about this as all of the
'getOrInsertFunction' functions on Module will default to the program
address space.
An overload has been added to Function::Create to abstract away the
details for most callers.
This is based on https://reviews.llvm.org/D37054 but without the changes to
make passing a Module to Function::Create() mandatory. I have also added
some more tests and fixed the LLParser to accept call instructions for
types in the program address space.
Reviewed By: bjope
Differential Revision: https://reviews.llvm.org/D47541
llvm-svn: 340519
In cases where the debugger load time is a worthwhile tradeoff (or less
costly - such as loading from a DWP instead of a variety of DWOs
(possibly over a high-latency/distributed filesystem)) against object
file size, it can be reasonable to disable pubnames and corresponding
gdb-index creation in the linker.
A backend-flag version of this was implemented for NVPTX in
D44385/r327994 - which was fine for NVPTX which wouldn't mix-and-match
CUs. Now that it's going to be a user-facing option (likely powered by
"-gno-pubnames", the same as GCC) it should be encoded in the
DICompileUnit so it can vary per-CU.
After this, likely the NVPTX support should be migrated to the metadata
& the previous flag implementation should be removed.
Reviewers: aprantl
Differential Revision: https://reviews.llvm.org/D50213
llvm-svn: 339939
Flags in DIBasicType will be used to pass attributes used in
DW_TAG_base_type, such as DW_AT_endianity.
Patch by Chirag Patel!
Differential Revision: https://reviews.llvm.org/D49610
llvm-svn: 339714
Summary:
Currently all type ids are emitted into the index file when it is
written. For distributed ThinLTO, that meant that all type ids were
being duplicated into every single distributed index file, regardless of
whether they were referenced, leading to huge amounts of unnecessary
duplication and size bloat.
Keep track of the type id GUIDs actually referenced by the GV summary
records being emitted, and only emit those type IDs.
Add a new test, and fix test/Assembler/thinlto-summary.ll so that all
type ids are referenced to prevent deletion in that test.
Reviewers: pcc
Subscribers: mehdi_amini, inglorion, eraman, steven_wu, dexonsmith, vitalybuka, llvm-commits
Differential Revision: https://reviews.llvm.org/D49565
llvm-svn: 337503
Summary:
Adds assembly parsing support for the module summary index (follow on
to r333335 which added the assembly writing support).
I added support to llvm-as to invoke the index parsing, so that it can
create either a bitcode file with a Module and a per-module index, or
a combined index without a Module.
I will send follow on patches soon to do the following:
- add support to tools such as llvm-lto2 to parse the per-module indexes
from assembly instead of bitcode when testing the thin link.
- verification support.
Depends on D47844 and D47842.
Reviewers: pcc, dexonsmith, mehdi_amini
Subscribers: inglorion, eraman, steven_wu, llvm-commits
Differential Revision: https://reviews.llvm.org/D47905
llvm-svn: 335602
Summary:
I discovered when writing the summary parsing support that the
per-module index builder and writer are computing the GUID from the
value name alone (ignoring the linkage type). This was ok since those
GUID were not emitted in the bitcode, and there are never multiple
conflicting names in a single module.
However, I don't see a reason for making the GUID computation different
for the per-module case. It also makes things simpler on the parsing
side to have the GUID computation consistent. So this patch changes the
summary analysis phase and the per-module summary writer to compute the
GUID using the facility on the GlobalValue.
Reviewers: pcc, dexonsmith
Subscribers: llvm-commits, inglorion
Differential Revision: https://reviews.llvm.org/D47844
llvm-svn: 335560
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is
!DILabel(scope: !1, name: "foo", file: !2, line: 3)
We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is
llvm.dbg.label(metadata !1)
It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.
We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.
Differential Revision: https://reviews.llvm.org/D45024
Patch by Hsiangkai Wang.
llvm-svn: 331841
See r331124 for how I made a list of files missing the include.
I then ran this Python script:
for f in open('filelist.txt'):
f = f.strip()
fl = open(f).readlines()
found = False
for i in xrange(len(fl)):
p = '#include "llvm/'
if not fl[i].startswith(p):
continue
if fl[i][len(p):] > 'Config':
fl.insert(i, '#include "llvm/Config/llvm-config.h"\n')
found = True
break
if not found:
print 'not found', f
else:
open(f, 'w').write(''.join(fl))
and then looked through everything with `svn diff | diffstat -l | xargs -n 1000 gvim -p`
and tried to fix include ordering and whatnot.
No intended behavior change.
llvm-svn: 331184
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.
To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.
Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.
Reviewers: pcc, mehdi_amini, dexonsmith
Reviewed By: dexonsmith
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45132
llvm-svn: 329334
Summary:
Introduce the ShadowCallStack function attribute. It's added to
functions compiled with -fsanitize=shadow-call-stack in order to mark
functions to be instrumented by a ShadowCallStack pass to be submitted
in a separate change.
Reviewers: pcc, kcc, kubamracek
Reviewed By: pcc, kcc
Subscribers: cryptoad, mehdi_amini, javed.absar, llvm-commits, kcc
Differential Revision: https://reviews.llvm.org/D44800
llvm-svn: 329108
Summary:
Useful to selectively disable importing into specific modules for
debugging/triaging/workarounds.
Reviewers: eraman
Subscribers: inglorion, llvm-commits
Differential Revision: https://reviews.llvm.org/D45062
llvm-svn: 328909
Summary:
When building with libFuzzer, converting control flow to selects or
obscuring the original operands of CMPs reduces the effectiveness of
libFuzzer's heuristics.
This patch provides an attribute to disable or modify certain optimizations
for optimal fuzzing signal.
Provides a less aggressive alternative to https://reviews.llvm.org/D44057.
Reviewers: vitalybuka, davide, arsenm, hfinkel
Reviewed By: vitalybuka
Subscribers: junbuml, mehdi_amini, wdng, javed.absar, hiraditya, llvm-commits, kcc
Differential Revision: https://reviews.llvm.org/D44232
llvm-svn: 328214
X86 Supports Indirect Branch Tracking (IBT) as part of Control-Flow Enforcement Technology (CET).
IBT instruments ENDBR instructions used to specify valid targets of indirect call / jmp.
The `nocf_check` attribute has two roles in the context of X86 IBT technology:
1. Appertains to a function - do not add ENDBR instruction at the beginning of the function.
2. Appertains to a function pointer - do not track the target function of this pointer by adding nocf_check prefix to the indirect-call instruction.
This patch implements `nocf_check` context for Indirect Branch Tracking.
It also auto generates `nocf_check` prefixes before indirect branchs to jump tables that are guarded by range checks.
Differential Revision: https://reviews.llvm.org/D41879
llvm-svn: 327767
In DWARF v5 the Line Number Program Header is extensible, allowing values with
new content types. In this extension a content type is added,
DW_LNCT_LLVM_source, which contains the embedded source code of the file.
Add new optional attribute for !DIFile IR metadata called source which contains
source text. Use this to output the source to the DWARF line table of code
objects. Analogously extend METADATA_FILE in Bitcode and .file directive in ASM
to support optional source.
Teach llvm-dwarfdump and llvm-objdump about the new values. Update the output
format of llvm-dwarfdump to make room for the new attribute on file_names
entries, and support embedded sources for the -source option in llvm-objdump.
Differential Revision: https://reviews.llvm.org/D42765
llvm-svn: 325970
Summary: The discussion and as per need, each vendor needs a way to keep the old fast flags and the new fast flags in the auto upgrade path of the IR upgrader. This revision addresses that issue.
Patched by Michael Berg
Reviewers: qcolombet, hans, steven_wu
Reviewed By: qcolombet, steven_wu
Subscribers: dexonsmith, vsk, mehdi_amini, andrewrk, MatzeB, wristow, spatel
Differential Revision: https://reviews.llvm.org/D43253
llvm-svn: 325525
Summary:
Gold plugin does not add pass to ThinLTO modules without useful symbols.
In this case ThinLTO can't create corresponding index file and some features, like CFI,
cannot be processes by backed correctly without index.
Given that we don't need the backed output we can request it to avoid
processing the module. This is implemented by this patch using new
"SkipModuleByDistributedBackend" flag.
Reviewers: pcc, tejohnson
Subscribers: mehdi_amini, inglorion, eraman, cfe-commits
Differential Revision: https://reviews.llvm.org/D42995
llvm-svn: 325411
Summary:
TypeID summaries are used by CFI and need to be serialized by ThinLTO
indexing for later use by LTO Backend.
Reviewers: tejohnson, pcc
Subscribers: mehdi_amini, inglorion, eraman, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D42611
llvm-svn: 325182
Rather than encode the absence of a checksum with a Kind variant, instead put
both the kind and value in a struct and wrap it in an Optional.
Differential Revision: http://reviews.llvm.org/D43043
llvm-svn: 324928
This patch is the LLVM part of fixing the issues, described in
https://bugs.llvm.org/show_bug.cgi?id=36168
* The representation of enumerator values in the debug info metadata now
contains a boolean flag isUnsigned, which determines how the bits of
the value are interpreted.
* The DW_TAG_enumeration type DIE now always (for DWARF version >= 3)
includes a DW_AT_type attribute, which refers to the underlying
integer type, as suggested in DWARFv4 (5.7 Enumeration Type Entries).
* The debug info metadata for enumeration type contains (in flags)
indication whether this is a C++11 "fixed enum".
* For C++11 enumeration with a fixed underlying type, the DIE also
includes the DW_AT_enum_class attribute (for DWARF version >= 4).
* Encoding of enumerator constants uses DW_FORM_sdata for signed values
and DW_FORM_udata for unsigned values, as suggested by DWARFv4 (7.5.4
Attribute Encodings).
The changes should be backwards compatible:
* the isUnsigned attribute is optional and defaults to false.
* if the underlying type for the enumeration is not available, the
enumerator values are considered signed.
* the FixedEnum flag defaults to clear.
* the bitcode format for DIEnumerator stores the unsigned flag bit #1 of
the first record element, so the format does not change and the zero
previously stored there is consistent with the false default for
IsUnsigned.
Differential Revision: https://reviews.llvm.org/D42734
llvm-svn: 324489
Vitaly Buka
Chandler Carruth
Alexander Richardson
David Blaikie
Adrian Prantl
Fangrui Song
Teresa Johnson
Shiva Chen
Nico Weber
Mandeep Singh Grang
Vlad Tsyrklevich
Matt Morehouse
Oren Ben Simhon
Scott Linder
Steven Wu
Rafael Espindola
Momchil Velikov