Currently we do not represent runtime preemption in the IR, which has several
drawbacks:
1) The semantics of GlobalValues differ depending on the object file format
you are targeting (as well as the relocation-model and -fPIE value).
2) We have no way of disabling inlining of run time interposable functions,
since in the IR we only know if a function is link-time interposable.
Because of this llvm cannot support elf-interposition semantics.
3) In LTO builds of executables we will have extra knowledge that a symbol
resolved to a local definition and can't be preemptable, but have no way to
propagate that knowledge through the compiler.
This patch adds preemptability specifiers to the IR with the following meaning:
dso_local --> means the compiler may assume the symbol will resolve to a
definition within the current linkage unit and the symbol may be accessed
directly even if the definition is not within this compilation unit.
dso_preemptable --> means that the compiler must assume the GlobalValue may be
replaced with a definition from outside the current linkage unit at runtime.
To ease transitioning dso_preemptable is treated as a 'default' in that
low-level codegen will still do the same checks it did previously to see if a
symbol should be accessed indirectly. Eventually when IR producers emit the
specifiers on all Globalvalues we can change dso_preemptable to mean 'always
access indirectly', and remove the current logic.
Differential Revision: https://reviews.llvm.org/D20217
llvm-svn: 316668
Summary:
When describing trunc/zext/sext/ptrtoint/inttoptr in the chapter
about Constant Expressions we now simply refer to the Instruction
Reference. As far as I know there are no difference when it comes
to the semantics and the argument constraints. The only difference
is that the syntax is slighly different for the constant expressions,
regarding the use of parenthesis in constant expressions.
Referring to the Instruction Reference is the same solution as
already used for several other operations, such as bitcast.
The main goal was to add information that vector types are allowed
also in trunc/zext/sext/ptrtoint/inttoptr constant expressions.
That was not explicitly mentioned earlier, and resulted in some
questions in the review of https://reviews.llvm.org/D38546
Reviewers: efriedma, majnemer
Reviewed By: efriedma
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39165
llvm-svn: 316429
Summary:
Updated the XRayExample docs with instructions for using the llvm-xray stacks
command.
Reviewers: dberris
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39106
llvm-svn: 316192
This patch adds a new kind of metadata that indicates the possible callees of
indirect calls.
Differential Revision: https://reviews.llvm.org/D37354
llvm-svn: 315944
static __global int Var = 0;
__global int* Ptr[] = {&Var};
...
In this case Var is a non premptable symbol and so its address can be used as the value of Ptr, with a base relative relocation that will add the delta between the ELF address and the actual load address. Such relocations do not require a symbol.
Differential Revision: https://reviews.llvm.org/D38909
llvm-svn: 315935
- Update docs to match llvm coding style
- Add missing FP16_OVFL bit for gfx9
- Fix the size of the kernel descriptor in the docs
Differential Revision: https://reviews.llvm.org/D38902
llvm-svn: 315822
This refers to a temporary path that can be shared across all tests,
identified by a particular label. This can be used for things like
caches.
At the moment, the character set for the LABEL is limited to C
identifier characters, plus '-', '+', '=', and '.'. This is the same
set of characters currently allowed in REQUIRES clause identifiers.
llvm-svn: 315697
Minor doc update that the FileCheck matcher supports POSIX ERE.
It also fixes a minor issue in the regexp describing a variable
name: underscores are allowed too.
Differential Revision: https://reviews.llvm.org/D38787
llvm-svn: 315679
Here we add a secondary option parser to llvm-isel-fuzzer (and provide
it for use with other fuzzers). With this, you can copy the fuzzer to
a name like llvm-isel-fuzzer=aarch64-gisel for a fuzzer that fuzzer
AArch64 with GlobalISel enabled, or fuzzer=x86_64 to fuzz x86, with no
flags required. This should be useful for running these in OSS-Fuzz.
Note that this handrolls a subset of cl::opts to recognize, rather
than embedding a complete command parser for argv[0]. If we find we
really need the flexibility of handling arbitrary options at some
point we can rethink this.
This re-applies 315545 using "=" instead of ":" as a separator for
arguments.
llvm-svn: 315557
It broke some tests on Windows:
Failing Tests (4):
LLVM :: tools/llvm-isel-fuzzer/execname-options.ll
LLVM :: tools/llvm-isel-fuzzer/missing-triple.ll
LLVM :: tools/llvm-isel-fuzzer/x86-empty-bc.ll
LLVM :: tools/llvm-isel-fuzzer/x86-empty.ll
> llvm-isel-fuzzer: Handle a subset of backend flags in the executable name
>
> Here we add a secondary option parser to llvm-isel-fuzzer (and provide
> it for use with other fuzzers). With this, you can copy the fuzzer to
> a name like llvm-isel-fuzzer:aarch64-gisel for a fuzzer that fuzzer
> AArch64 with GlobalISel enabled, or fuzzer:x86_64 to fuzz x86, with no
> flags required. This should be useful for running these in OSS-Fuzz.
>
> Note that this handrolls a subset of cl::opts to recognize, rather
> than embedding a complete command parser for argv[0]. If we find we
> really need the flexibility of handling arbitrary options at some
> point we can rethink this.
llvm-svn: 315554
Here we add a secondary option parser to llvm-isel-fuzzer (and provide
it for use with other fuzzers). With this, you can copy the fuzzer to
a name like llvm-isel-fuzzer:aarch64-gisel for a fuzzer that fuzzer
AArch64 with GlobalISel enabled, or fuzzer:x86_64 to fuzz x86, with no
flags required. This should be useful for running these in OSS-Fuzz.
Note that this handrolls a subset of cl::opts to recognize, rather
than embedding a complete command parser for argv[0]. If we find we
really need the flexibility of handling arbitrary options at some
point we can rethink this.
llvm-svn: 315545
This patch adds a post-linking pass which replaces the function pointer of enqueued
block kernel with a global variable (runtime handle) and adds
runtime-handle attribute to the enqueued block kernel.
In LLVM CodeGen the runtime-handle metadata will be translated to
RuntimeHandle metadata in code object. Runtime allocates a global buffer
for each kernel with RuntimeHandel metadata and saves the kernel address
required for the AQL packet into the buffer. __enqueue_kernel function
in device library knows that the invoke function pointer in the block
literal is actually runtime handle and loads the kernel address from it
and puts it into AQL packet for dispatching.
This cannot be done in FE since FE cannot create a unique global variable
with external linkage across LLVM modules. The global variable with internal
linkage does not work since optimization passes will try to replace loads
of the global variable with its initialization value.
Differential Revision: https://reviews.llvm.org/D38610
llvm-svn: 315352
At the last LLVM dev meeting we had a debug info for optimized code
BoF session. In that session I presented some graphs that showed how
the quality of the debug info produced by LLVM changed over the last
couple of years. This is a cleaned up version of the patch I used to
collect the this data. It is implemented as an extension of
llvm-dwarfdump, adding a new --statistics option. The intended
use-case is to automatically run this on the debug info produced by,
e.g., our bots, to identify eyebrow-raising changes or regressions
introduced by new transformations that we could act on.
In the current form, two kinds of data are being collected:
- The number of variables that have a debug location versus the number
of variables in total (this takes into account inlined instances of
the same function, so if a variable is completely missing form only
one instance it will be found).
- The PC range covered by variable location descriptions versus the PC
range of all variables' containing lexical scopes.
The output format is versioned and extensible, so I'm looking forward
to both bug fixes and ideas for other data that would be interesting
to track.
Differential Revision: https://reviews.llvm.org/D36627
llvm-svn: 315101
The fix is to avoid invalidating our insertion point in
replaceDbgDeclare:
Builder.insertDeclare(NewAddress, DIVar, DIExpr, Loc, InsertBefore);
+ if (DII == InsertBefore)
+ InsertBefore = &*std::next(InsertBefore->getIterator());
DII->eraseFromParent();
I had to write a unit tests for this instead of a lit test because the
use list order matters in order to trigger the bug.
The reduced C test case for this was:
void useit(int*);
static inline void inlineme() {
int x[2];
useit(x);
}
void f() {
inlineme();
inlineme();
}
llvm-svn: 313905
.. as well as the two subsequent changes r313826 and r313875.
This leads to segfaults in combination with ASAN. Will forward repro
instructions to the original author (rnk).
llvm-svn: 313876
Summary:
The documentation refers to a boolean that controls whether response files are
handled, but this is incorrect. Since r165535, response files are always
enabled.
Reviewers: compnerd, rafael
Reviewed By: compnerd
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38095
llvm-svn: 313830
Summary:
This implements the design discussed on llvm-dev for better tracking of
variables that live in memory through optimizations:
http://lists.llvm.org/pipermail/llvm-dev/2017-September/117222.html
This is tracked as PR34136
llvm.dbg.addr is intended to be produced and used in almost precisely
the same way as llvm.dbg.declare is today, with the exception that it is
control-dependent. That means that dbg.addr should always have a
position in the instruction stream, and it will allow passes that
optimize memory operations on local variables to insert llvm.dbg.value
calls to reflect deleted stores. See SourceLevelDebugging.rst for more
details.
The main drawback to generating DBG_VALUE machine instrs is that they
usually cause LLVM to emit a location list for DW_AT_location. The next
step will be to teach DwarfDebug.cpp how to recognize more DBG_VALUE
ranges as not needing a location list, and possibly start setting
DW_AT_start_offset for variables whose lifetimes begin mid-scope.
Reviewers: aprantl, dblaikie, probinson
Subscribers: eraman, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D37768
llvm-svn: 313825
Summary: Resubmission of D37937. Fixed i386 target building (conversion from std::size_t& to uint64_t& failed). Fixed documentation warning failure about docs/CFIVerify.rst not being in the tree.
Reviewers: vlad.tsyrklevich
Reviewed By: vlad.tsyrklevich
Patch by Mitch Phillips
Subscribers: sbc100, mgorny, pcc, llvm-commits, kcc
Differential Revision: https://reviews.llvm.org/D38089
llvm-svn: 313809
Summary: Resubmission of D37937. Fixed i386 target building (conversion from std::size_t& to uint64_t& failed). Fixed documentation warning failure about docs/CFIVerify.rst not being in the tree.
Reviewers: vlad.tsyrklevich
Reviewed By: vlad.tsyrklevich
Patch by Mitch Phillips
Subscribers: mgorny, pcc, llvm-commits, kcc
Differential Revision: https://reviews.llvm.org/D38089
llvm-svn: 313798
Sean Fertile