length excluding the table header. Instead it must encode the contribution length minus the length
field itself.
Reviewer: JDevliegehere
Differential Revision: https://reviews.llvm.org/D45922
llvm-svn: 332030
Summary:
Experimental data flow tracer for fuzz targets.
Allows to tell which bytes of the input affect which functions of the fuzz target.
We previously attempted to use DFSan directly in the libFuzzer process,
and that didn't work nicely.
Now we will try to collect the data flow information for the seed corpus
in a separate process (using this tracer), and then use it in the regular libFuzzer runs.
Reviewers: morehouse, pcc, Dor1s
Reviewed By: morehouse, Dor1s
Subscribers: delcypher, #sanitizers, llvm-commits
Differential Revision: https://reviews.llvm.org/D46666
llvm-svn: 332029
Summary:
The Itanium ABI requires that the type info for pointer-to-incomplete types to have internal linkage, so that it doesn't interfere with the type info once completed. Currently it also marks the type info name as internal as well. However, this causes a bug with the STL implementations, which use the type info name pointer to perform ordering and hashing of type infos.
For example:
```
// header.h
struct T;
extern std::type_info const& Info;
// tu_one.cpp
#include "header.h"
std::type_info const& Info = typeid(T*);
// tu_two.cpp
#include "header.h"
struct T {};
int main() {
auto &TI1 = Info;
auto &TI2 = typeid(T*);
assert(TI1 == TI2); // Fails
assert(TI1.hash_code() == TI2.hash_code()); // Fails
}
```
This patch fixes the STL bug by emitting the type info name as linkonce_odr when the type-info is for a pointer-to-incomplete type.
Note that libc++ could fix this without a compiler change, but the quality of fix would be poor. The library would either have to:
(A) Always perform strcmp/string hashes.
(B) Determine if we have a pointer-to-incomplete type, and only do strcmp then. This would require an ABI break for libc++.
Reviewers: rsmith, rjmccall, majnemer, vsapsai
Reviewed By: rjmccall
Subscribers: smeenai, cfe-commits
Differential Revision: https://reviews.llvm.org/D46665
llvm-svn: 332028
This commit relands r331905.
r331904 added SrcMgr::CharacteristicKind to the InclusionDirective
callback, this revision updates instances of it in clang-tools-extra.
llvm-svn: 332023
This commit relands r331904.
Adding a SrcMgr::CharacteristicKind parameter to the InclusionDirective
in PPCallbacks, and updating calls to that function. This will be useful
in https://reviews.llvm.org/D43778 to determine which includes are
system
headers.
Differential Revision: https://reviews.llvm.org/D46614
llvm-svn: 332021
Summary:
The SanitizerCommon-lsan-x86_64-Linux test failed due to the address of
the very first allocation ending up in the stack through "delete[]".
Workaround this by performing another allocation. The issue was only
present with optimization enabled, the test would pass with -O0.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D46650
llvm-svn: 332020
In general, it's difficult to poke the ConstantExpr code in CFLAA, since
LLVM is so great at eagerly reducing ConstantExprs. :)
Sadly, this only shows a functional difference from before the patch
because CFLAA has some special logic around taking loads of non-pointers
into account. Namely, with the broken select behavior, CFLAA will
completely fail to take note of @g3. Since CFLAA doesn't have any record
about @g3 when we do an alias query for @g3 and %a, it conservatively
answers MayAlias. When we properly take @g3 into account with the new
select logic, we get NoAlias for this query.
I suspect that the aforementioned "special logic" isn't completely
correct, but this test-case should prevent future wonky aliasing results
from appearing for these flavors of ConstantExprs, so I think it's still
worth having.
llvm-svn: 332017
Added initial support for L2 parallelism in SPMD mode. Note, though,
that the orphaned parallel directives are not currently supported in
SPMD mode.
llvm-svn: 332016
Accessing the members of a large data structures needs a lot of GEPs which
usually have large offsets due to the size of the underlying data structure. If
the offsets are too large to fit into the r+i addressing mode, these GEPs cannot
be sunk to their users' blocks and many extra registers are needed then to carry
the values of these GEPs.
This patch tries to split a large data struct starting from %base like the
following.
Before:
BB0:
%base =
BB1:
%gep0 = gep %base, off0
%gep1 = gep %base, off1
%gep2 = gep %base, off2
BB2:
%load1 = load %gep0
%load2 = load %gep1
%load3 = load %gep2
After:
BB0:
%base =
%new_base = gep %base, off0
BB1:
%new_gep0 = %new_base
%new_gep1 = gep %new_base, off1 - off0
%new_gep2 = gep %new_base, off2 - off0
BB2:
%load1 = load i32, i32* %new_gep0
%load2 = load i32, i32* %new_gep1
%load3 = load i32, i32* %new_gep2
In the above example, the struct is split into two parts. The first part still
starts from %base and the second part starts from %new_base. After the
splitting, %new_gep1 and %new_gep2 have smaller offsets and then can be sunk to
BB2 and folded into their users.
The algorithm to split data structure is simple and very similar to the work of
merging SExts. First, it collects GEPs that have large offsets when iterating
the blocks. Second, it splits the underlying data structures and updates the
collected GEPs to use smaller offsets.
Differential Revision: https://reviews.llvm.org/D42759
llvm-svn: 332015
Summary:
- Adds getters for the line, column, and scope of a DILocation
- Adds getters for the name, size in bits, offset in bits, alignment in bits, line, and flags of a DIType
Reviewers: whitequark, harlanhaskins, deadalnix
Reviewed By: whitequark
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46627
llvm-svn: 332014
Merging data segments produces smaller code sizes because each segment
has some boilerplate. Therefore, merging data segments is generally the
right approach, especially with wasm where binaries are typically
delivered over the network.
However, when analyzing wasm binaries, it can be helpful to get a
conservative picture of which functions are using which data
segments[0]. Perhaps there is a large data segment that you didn't
expect to be included in the wasm, introduced by some library you're
using, and you'd like to know which library it was. In this scenario,
merging data segments only makes the analysis worse.
Alternatively, perhaps you will remove some dead functions by-hand[1]
that can't be statically proven dead by the compiler or lld, and
removing these functions might make some data garbage collect-able, and
you'd like to run `--gc-sections` again so that this now-unused data can
be collected. If the segments were originally merged, then a single use
of the merged data segment will entrench all of the data.
[0] https://github.com/rustwasm/twiggy
[1] https://github.com/fitzgen/wasm-snip
Patch by Nick Fitzgerald!
Differential Revision: https://reviews.llvm.org/D46417
llvm-svn: 332013
This is most useful when using lld-link on a non-Win host (but it might become
useful on Windows too if lld also grows a fansi-escape-codes flag).
Also make the help for --color-diagnostic mention the valid values in ELF and
wasm, and print the flag name with two dashes in diags, since the one-dash form
is seen as a list of many one-letter flags in some contexts.
https://reviews.llvm.org/D46693
llvm-svn: 332012
Summary: The final -wasm component has been the default for some time now.
Subscribers: jfb, dschuff, jgravelle-google, eraman, aheejin, JDevlieghere, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D46342
llvm-svn: 332007
These symbols only get included in the output symbols table if
they are used in a relocation.
This behaviour matches more closely the ELF object writer.
Differential Revision: https://reviews.llvm.org/D46561
llvm-svn: 332005
Summary:
Fixed two non-standard usages of sem_open in the libFuzzer library and
one NetBSD-related modification with test script.
- The return value to indicate error should be SEM_FAILED instead of
(void *)-1 (please refer to "RETURN VALUE" section in this [[
http://pubs.opengroup.org/onlinepubs/9699919799/functions/sem_open.html
| page ]]). Actually, SEM_FAILED != (void *)-1 holds in NetBSD.
- The SharedMemoryRegion::SemName function should return name
starting with slash. Because the behaviour of name which does not
start with slash is unspecified as the [[
http://pubs.opengroup.org/onlinepubs/9699919799/functions/sem_open.html
| "DESCRIPTION" section ]] specified:
> If name does not begin with the <slash> character, the effect is implementation-defined.
- The length of name is limited to 14 in NetBSD, it is suggested to
reduce the length of equivalence server name in the test script.
Patch by: Yang Zheng
Reviewers: vitalybuka, krytarowski, kcc
Reviewed By: kcc
Subscribers: kcc, #sanitizers, llvm-commits, joerg
Differential Revision: https://reviews.llvm.org/D46622
llvm-svn: 332003
This is a follow up to the rL330983. The patch teaches ld, sd, and lld
commands accept 32-bit memory offsets by replacing `mem_simm16` operand
to `mem_simmptr`. In fact, these commands should accept 64-bit offsets,
but so large offsets require another command expanding and will be
supported by a separate patch.
Differential Revision: https://reviews.llvm.org/D46629
llvm-svn: 331997
This is a follow up to the rL330983. The patch teaches lh and lhu
commands accepts 32-bit memory offsets by replacing `mem_simm16` operand
to `mem_simmptr`.
Differential Revision: https://reviews.llvm.org/D46513
llvm-svn: 331996
This diff slightly reorganizes the tests and improves
the test coverage of help messages / error reports.
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D46589
llvm-svn: 331993
With nnan, there's no need for the masked merge / blend
sequence (that probably costs much more than the min/max
instruction).
Somewhere between clang 5.0 and 6.0, we started producing
these intrinsics for fmax()/fmin() in C source instead of
libcalls or fcmp/select. The backend wasn't prepared for
that, so we regressed perf in those cases.
Note: it's possible that other targets have similar problems
as seen here.
Noticed while investigating PR37403 and related bugs:
https://bugs.llvm.org/show_bug.cgi?id=37403
The IR FMF propagation cases still don't work. There's
a proposal that might fix those cases in D46563.
llvm-svn: 331992
Summary:
This change teaches DSE that the atomic memory intrinsics can be overwriten
partially in the same way as the non-atomic forms. Specifically, that the
atomic memcpy & memset can be shortened at the end and that the atomic memset
can be shortened at the beginning, if they partially overwritten
by later stores.
Reviewers: mkazantsev, skatkov, apilipenko, efriedma, rsmith, spatel, filcab, sanjoy
Reviewed By: efriedma
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45584
llvm-svn: 331991
Fixes bug https://bugs.llvm.org/show_bug.cgi?id=37339.
InlineAsm is only uniqued if the FunctionTypes are exactly the
same, while cmpTypes() for example considers all pointer types
in the default address space to be the same. For this reason
the end of cmpInlineAsm() can be reached.
This patch replaces the unreachable assertion with a check that
the function types are not identical.
Differential Revision: https://reviews.llvm.org/D46495
Reviewers: jfb
llvm-svn: 331990
Clang 6.0 was updated to create these intrinsics rather than
libcalls or fcmp/select, but the backend wasn't prepared to
handle that optimally.
This bug is not the primary reason for PR37403:
https://bugs.llvm.org/show_bug.cgi?id=37403
...but it's probably more important for x86 perf.
llvm-svn: 331988
Summary:
The combine in rebuildSetCC may be combined to another
node leaving our references stale. Keep a handle on
it to avoid stale references.
Fixes PR36602.
Reviewers: dbabokin, RKSimon, eli.friedman, davide
Subscribers: hiraditya, uabelho, JesperAntonsson, qcolombet, llvm-commits
Differential Revision: https://reviews.llvm.org/D46404
llvm-svn: 331985
Sanjay Patel