After rL365286 I had failing test:
LLVM :: tools/gold/X86/v1.12/thinlto_emit_linked_objects.ll
It was failing with the output:
$ llvm-bcanalyzer --dump llvm/test/tools/gold/X86/v1.12/Output/thinlto_emit_linked_objects.ll.tmp3.o.thinlto.bc
Expected<T> must be checked before access or destruction.
Unchecked Expected<T> contained error:
Unexpected end of file reading 0 of 0 bytesStack dump:
Change-Id: I07e03262074ea5e0aae7a8d787d5487c87f914a2
llvm-svn: 366387
Add "memtag" sanitizer that detects and mitigates stack memory issues
using armv8.5 Memory Tagging Extension.
It is similar in principle to HWASan, which is a software implementation
of the same idea, but there are enough differencies to warrant a new
sanitizer type IMHO. It is also expected to have very different
performance properties.
The new sanitizer does not have a runtime library (it may grow one
later, along with a "debugging" mode). Similar to SafeStack and
StackProtector, the instrumentation pass (in a follow up change) will be
inserted in all cases, but will only affect functions marked with the
new sanitize_memtag attribute.
Reviewers: pcc, hctim, vitalybuka, ostannard
Subscribers: srhines, mehdi_amini, javed.absar, kristof.beyls, hiraditya, cryptoad, steven_wu, dexonsmith, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D64169
llvm-svn: 366123
This recommits r365750 (git commit 8b222ecf27)
Original message:
Currently invalid bitcode files can cause a crash, when OpNum exceeds
the number of elements in Record, like in the attached bitcode file.
The test case was generated by clusterfuzz: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=15698
Reviewers: t.p.northover, thegameg, jfb
Reviewed By: jfb
Differential Revision: https://reviews.llvm.org/D64507
llvm-svn: 365750jkkkk
llvm-svn: 366018
At the moment, bitcode files with invalid forward reference can easily
cause the bitcode reader to run out of memory, by creating a forward
reference with a very high index.
We can use the size of the bitcode file as an upper bound, because a
valid bitcode file can never contain more records. This should be
sufficient to fail early in most cases. The only exception is large
files with invalid forward references close to the file size.
There are a couple of clusterfuzz runs that fail with out-of-memory
because of very high forward references and they should be fixed by this
patch.
A concrete example for this is D64507, which causes out-of-memory on
systems with low memory, like the hexagon upstream bots.
Reviewers: t.p.northover, thegameg, jfb, efriedma, hfinkel
Reviewed By: jfb
Differential Revision: https://reviews.llvm.org/D64577
llvm-svn: 366017
Introduce and deduce "nosync" function attribute to indicate that a function
does not synchronize with another thread in a way that other thread might free memory.
Reviewers: jdoerfert, jfb, nhaehnle, arsenm
Subscribers: wdng, hfinkel, nhaenhle, mehdi_amini, steven_wu,
dexonsmith, arsenm, uenoku, hiraditya, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D62766
llvm-svn: 365830
Currently invalid bitcode files can cause a crash, when OpNum exceeds
the number of elements in Record, like in the attached bitcode file.
The test case was generated by clusterfuzz: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=15698
Reviewers: t.p.northover, thegameg, jfb
Reviewed By: jfb
Differential Revision: https://reviews.llvm.org/D64507
llvm-svn: 365750
Summary: We emit CFI_FUNCTION_DEFS and CFI_FUNCTION_DECLS to
distributed ThinLTO indices to implement indirect function call
checking. This change causes us to only emit entries for functions
that are either defined or used by the module we're writing the index
for (instead of all functions in the combined index), which can make
the indices substantially smaller.
Fixes PR42378.
Reviewers: pcc, vitalybuka, eugenis
Subscribers: mehdi_amini, hiraditya, dexonsmith, arphaman, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63887
llvm-svn: 365537
This patch adds a function attribute, nofree, to indicate that a function does
not, directly or indirectly, call a memory-deallocation function (e.g., free,
C++'s operator delete).
Reviewers: jdoerfert
Differential Revision: https://reviews.llvm.org/D49165
llvm-svn: 365336
This allows us to use the analyzer from unit tests.
* Refactor the interface to use proper error handling for most functions
after JF's work.
* Move everything into a BitstreamAnalyzer class.
* Move that to Bitcode/BitcodeAnalyzer.h.
Differential Revision: https://reviews.llvm.org/D64116
llvm-svn: 365286
Reintroduces the scalable vector IR type from D32530, after it was reverted
a couple of times due to increasing chromium LTO build times. This latest
incarnation removes the walk over aggregate types from the verifier entirely,
in favor of rejecting scalable vectors in the isValidElementType methods in
ArrayType and StructType. This removes the 70% degradation observed with
the second repro tarball from PR42210.
Reviewers: thakis, hans, rengolin, sdesmalen
Reviewed By: sdesmalen
Differential Revision: https://reviews.llvm.org/D64079
llvm-svn: 365203
It's possible that some function can load and store the same
variable using the same constant expression:
store %Derived* @foo, %Derived** bitcast (%Base** @bar to %Derived**)
%42 = load %Derived*, %Derived** bitcast (%Base** @bar to %Derived**)
The bitcast expression was mistakenly cached while processing loads,
and never examined later when processing store. This caused @bar to
be mistakenly treated as read-only variable. See load-store-caching.ll.
llvm-svn: 365188
This reverts r365040 (git commit 5cacb91475)
Speculatively reverting, since this appears to have broken check-lld on
Linux. Partial analysis in https://crbug.com/981168.
llvm-svn: 365097
This moves Bitcode/Bitstream*, Bitcode/BitCodes.h to Bitstream/.
This is needed to avoid a circular dependency when using the bitstream
code for parsing optimization remarks.
Since Bitcode uses Core for the IR part:
libLLVMRemarks -> Bitcode -> Core
and Core uses libLLVMRemarks to generate remarks (see
IR/RemarkStreamer.cpp):
Core -> libLLVMRemarks
we need to separate the Bitstream and Bitcode part.
For clang-doc, it seems that it doesn't need the whole bitcode layer, so
I updated the CMake to only use the bitstream part.
Differential Revision: https://reviews.llvm.org/D63899
llvm-svn: 365091
Summary:
If LTOUnit splitting is disabled, the module summary analysis computes
the summary information necessary to perform single implementation
devirtualization during the thin link with the index and no IR. The
information collected from the regular LTO IR in the current hybrid WPD
algorithm is summarized, including:
1) For vtable definitions, record the function pointers and their offset
within the vtable initializer (subsumes the information collected from
IR by tryFindVirtualCallTargets).
2) A record for each type metadata summarizing the vtable definitions
decorated with that metadata (subsumes the TypeIdentiferMap collected
from IR).
Also added are the necessary bitcode records, and the corresponding
assembly support.
The follow-on index-based WPD patch is D55153.
Depends on D53890.
Reviewers: pcc
Subscribers: mehdi_amini, Prazek, inglorion, eraman, steven_wu, dexonsmith, arphaman, llvm-commits
Differential Revision: https://reviews.llvm.org/D54815
llvm-svn: 364960
This patch introduces a new function attribute, willreturn, to indicate
that a call of this function will either exhibit undefined behavior or
comes back and continues execution at a point in the existing call stack
that includes the current invocation.
This attribute guarantees that the function does not have any endless
loops, endless recursion, or terminating functions like abort or exit.
Patch by Hideto Ueno (@uenoku)
Reviewers: jdoerfert
Subscribers: mehdi_amini, hiraditya, steven_wu, dexonsmith, lebedev.ri, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62801
llvm-svn: 364555
There is existing bitcode that we need to support where the structured nature
of pointer types is used to derive the result type of some operation. For
example a GEP's operation and result will be based on its input Type.
When pointers become opaque, the BitcodeReader will still have access to this
information because it's explicitly told how to construct the more complex
types used, but this information will not be attached to any Value that gets
looked up. This changes BitcodeReader so that in all places which use type
information in this manner, it's derived from a side-table rather than from the
Value in question.
llvm-svn: 364550
We saw a 70% ThinLTO link time increase in Chromium for Android, see
crbug.com/978817. Sounds like more of PR42210.
> Recommit of D32530 with a few small changes:
> - Stopped recursively walking through aggregates in
> the verifier, so that we don't impose too much
> overhead on large modules under LTO (see PR42210).
> - Changed tests to match; the errors are slightly
> different since they only report the array or
> struct that actually contains a scalable vector,
> rather than all aggregates which contain one in
> a nested member.
> - Corrected an older comment
>
> Reviewers: thakis, rengolin, sdesmalen
>
> Reviewed By: sdesmalen
>
> Differential Revision: https://reviews.llvm.org/D63321
llvm-svn: 364543