This patch
addresses a null pointer dereference issue reported by static analyzer
tool in the
`EmitSVETupleSetOrGet()` and `EmitSVETupleCreate()` functions.
Previously, the function
assumed that the result of `dyn_cast<>` to `ScalableVectorType` would
always be non-null,
which is not guaranteed.
The fix introduces a null check after the `dyn_cast<>` operation. If the
cast fails and
`SingleVecTy` is null, the function now returns `nullptr` to indicate an
error. This prevents the
dereference of a null pointer, which could lead to undefined behavior.
Additionally, the assert message has been corrected to accurately
reflect the expected
conditions.
These changes collectively enhance the robustness of the code by
ensuring type safety and preventing runtime errors due to improper type
casting.
This is the first patch in a series of patches for the Sandbox Vectorizer project.
SandboxIR is not tightly coupled to the Sandbox Vectorizer and could be used
independently as a transactional layer on top of LLVM IR.
For a detailed description of the project please refer to the RFC:
https://discourse.llvm.org/t/rfc-sandbox-vectorizer-an-experimental-modular-vectorizer/79059
This patch adds some basic boilerplate code for the SandboxIR which includes
parts of the SandboxIR `Value`, `User` and `Context` classes.
The entire body of the function is inside of an if-statement, followed
by a "return false". Invert the condition and return early, unindent
and clang-format the function.
Similar to other attributes in Binding, the `PyAffineMapAttribute`
should include a value attribute to enable users to directly retrieve
the `AffineMap` from the `AffineMapAttr`.
The lifetime bound warning in Clang currently only considers
initializations. This patch extends the warning to include assignments.
- **Support for assignments of built-in pointer types**: this is done is
by reusing the existing statement-local implementation. Clang now warns
if the pointer is assigned to a temporary object that being destoryed at
the end of the full assignment expression.
With this patch, we will detect more cases under the on-by-default
diagnostic `-Wdangling`. I have added a new category for this specific
diagnostic so that people can temporarily disable it if their codebase
is not yet clean.
This is the first step to address #63310, focusing only on pointer
types. Support for C++ assignment operators will come in a follow-up
patch.
Fixes#54492
This is exactly as originally landed in #95129,
but now the minimal Z3 version was increased to meet this change in #96682.
https://discourse.llvm.org/t/bump-minimal-z3-requirements-from-4-7-1-to-4-8-9/79664/4
---
This patch is a functional change.
https://discourse.llvm.org/t/analyzer-rfc-taming-z3-query-times/79520
As a result of this patch, individual Z3 queries in refutation will be
bound by 300ms. Every report equivalence class will be processed in at
most 1 second.
The heuristic should have only really marginal observable impact -
except for the cases when we had big report eqclasses with long-running
(15s) Z3 queries, where previously CSA effectively halted. After this
patch, CSA will tackle such extreme cases as well.
(cherry picked from commit eacc3b3504)
This patch allows expressions to reference entities in anonymous
namespaces. Previously this would have resulted in:
```
(lldb) expr foo::FooAnonymousVar
error: <user expression 0>:1:6: no member named 'FooAnonymousVar' in namespace 'foo'
1 | foo::FooAnonymousVar
| ~~~~~^
```
We already allow such lookups through inline namespaces, and for the
purposes of lookup, anonymous namespaces shouldn't behave any different.
Fixes https://github.com/llvm/llvm-project/issues/96963.
This extends the existing register fields support from AArch64 Linux
to AArch64 FreeBSD. So you will now see output like this:
```
(lldb) register read cpsr
cpsr = 0x60000200
= (N = 0, Z = 1, C = 1, V = 0, DIT = 0, SS = 0, IL = 0, SSBS = 0, D = 1, A = 0, I = 0, F = 0, nRW = 0, EL = 0, SP = 0)
```
Linux and FreeBSD both have HWCAP/HWCAP2 so the detection mechanism
is the same and I've renamed the detector class to reflect that.
I have confirmed that FreeBSD's treatment of CPSR (spsr as the kernel
calls it) is similair enough that we can use the same field information.
(see `sys/arm64/include/armreg.h` and `PSR_SETTABLE_64`)
For testing I've enabled the same live process test as Linux
and added a shell test using an existing FreeBSD core file.
Note that the latter does not need XML support because when reading
a core file we are not sending the information via target.xml,
it's just internal to LLDB.
Disable conversion of a `(select (icmp))` when it would result in more
instructions `(xor (lshr (and)))`. This transformation produces more
instructions and can interfere with other more profitable folds for
`select`. For example before this change the following folding would
occur:
```llvm
%1 = icmp slt i32 %X, 0
%2 = select i1 %1, i64 0, i64 8
```
to
```llvm
%1 = lshr i32 %X, 28
%2 = and i32 %1, 8
%3 = xor i32 %2, 8
%4 = zext nneg i32 %3 to i64
```
Timers are an out-of-line function call and a global variable access,
here twice per emitted instruction. At this granularity, not only the
time results become skewed, but the timers also add a performance
overhead when profiling is disabled. Also outside of the innermost loop,
timers add a measurable overhead. As this is quite expensive for a
mostly unused profiling facility, remove the timers.
Fixes#39650.
Extract an adjustKnownBitsForSelectArm() helper for the
ValueTracking logic and make use of it in SimplifyDemandedBits().
This fixes a consistency violation under instcombine-verify-known-bits.
This PR reverts #95290 and the one-liner followup PR #96494.
I received some substantial feedback on #95290, which I plan to address
in a future PR.
I've also received feedback that because the change emits errors where
they were not emitted before, we should at least have a flag to disable
the stricter warnings.
We're missing SimplifyDemandedBits styles of optimizations,
so one case differs from the DAG from not trimming the constant.
The other case is an optimization we get that the DAG doesn't do to
split the 64-bit shift.
https://reviews.llvm.org/D138082
Start functions with BTI in order to identify the function as a valid
branch target.
Also add the BTI marker to tsan_rtl_aarch64.S.
With this patch, libclang_rt.tsan.so can now be generated with
DT_AARCH64_BTI_PLT when built with -mbranch-protection=standard.
Use range-based for loops. In addition, extracted a loop from
`CXXRecordDecl::completeDefinition` to eliminate the `Done` flag, and
only construct `MyFinalOverriders` when `FinalOverriders` is null.
This patch addresses a use-after-move issue, reported by static analyzer
tool, by clearing the `PotentiallyInterestingDecls` deque after it has
been moved to `MaybeInterestingDecls`.
The fix ensures that the subsequent assert statement correctly checks
for an empty state, preventing any undefined behavior in
ASTReader::PassInterestingDeclsToConsumer().
### Background
It's surprisingly common for C++ code in the wild to conditionally
show/hide declarations to Doxygen through the use of preprocessor
directives. One especially common version of this pattern is
demonstrated below:
```cpp
/// @brief Test comment
#ifdef DOXYGEN_BUILD_ENABLED
template<typename T>
#else
template <typename T>
typename std::enable_if<std::is_integral<T>::value>::type
#endif
void f() {}
```
There are more examples I've collected below to demonstrate usage of
this pattern:
- Example 1:
[Magnum](8538610fa2/src/Magnum/Resource.h (L117-L127))
- Example 2:
[libcds](9985d2a87f/cds/container/michael_list_nogc.h (L36-L54))
- Example 3:
[rocPRIM](609ae19565/rocprim/include/rocprim/block/detail/block_reduce_raking_reduce.hpp (L60-L65))
From my research, it seems like the most common rationale for this
functionality is hiding difficult-to-parse code from Doxygen, especially
where template metaprogramming is concerned.
Currently, Clang does not support attaching comments to decls if there
are preprocessor comments between the comment and the decl. This is
enforced here:
b6ebea7972/clang/lib/AST/ASTContext.cpp (L284-L287)
Alongside preprocessor directives, any instance of `;{}#@` between a
comment and decl will cause the comment to not be attached to the decl.
#### Rationale
It would be nice for Clang-based documentation tools, such as
[hdoc](https://hdoc.io), to support code using this pattern. Users
expect to see comments attached to the relevant decl — even if there is
an `#ifdef` in the way — which Clang does not currently do.
#### History
Originally, commas were also in the list of "banned" characters, but
were removed in `b534d3a0ef69`
([link](b534d3a0ef))
because availability macros often have commas in them. From my reading
of the code, it appears that the original intent of the code was to
exclude macros and decorators between comments and decls, possibly in an
attempt to properly attribute comments to macros (discussed further in
"Complications", below). There's some more discussion here:
https://reviews.llvm.org/D125061.
### Change
This modifies Clang comment parsing so that comments are attached to
subsequent declarations even if there are preprocessor directives
between the end of the comment and the start of the decl. Furthermore,
this change:
- Adds tests to verify that comments are attached to their associated
decls even if there are preprocessor directives in between
- Adds tests to verify that current behavior has not changed (i.e. use
of the other characters between comment and decl will result in the
comment not being attached to the decl)
- Updates existing `lit` tests which would otherwise break.
#### Complications
Clang [does not yet
support](https://github.com/llvm/llvm-project/issues/38206) attaching
doc comments to macros. Consequently, the change proposed in this RFC
affects cases where a doc comment attached to a macro is followed
immediately by a normal declaration. In these cases, the macro's doc
comments will be attached to the subsequent decl. Previously they would
be ignored because any preprocessor directives between a comment and a
decl would result in the comment not being attached to the decl. An
example of this is shown below.
```cpp
/// Doc comment for a function-like macro
/// @param n
/// A macro argument
#define custom_sqrt(n) __internal_sqrt(n)
int __internal_sqrt(int n) { return __builtin_sqrt(n); }
// NB: the doc comment for the custom_sqrt macro will actually be attached to __internal_sqrt!
```
There is a real instance of this problem in the Clang codebase, namely
here:
be10070f91/clang/lib/Headers/amxcomplexintrin.h (L65-L114)
As part of this RFC, I've added a semicolon to break up the Clang
comment parsing so that the `-Wdocumentation` errors go away, but this
is a hack. The real solution is to fix Clang comment parsing so that doc
comments are properly attached to macros, however this would be a large
change that is outside of the scope of this RFC.
Currently, an AsmPrinterHandler has several methods that allow to
dynamically hook in unwind or debug info emission, e.g. at begin/end of
every function or instruction. The class hierarchy and the actually
overridden functions are as follows:
(SymSz=setSymbolSize, mFE=markFunctionEnd, BBS=BasicBlockSection,
FL=Funclet; b=beginX, e=endX)
SymSz Mod Fn mFE BBS FL Inst
AsmPrinterHandler - - - - - - -
` PseudoProbeHandler - - - - - - -
` WinCFGuard - e e - - - -
` EHStreamer - - - - - - -
` DwarfCFIException - e be - be - -
` ARMException - - be e - - -
` AIXException - - e - - - -
` WinException - e be e - be -
` WasmException - e be - - - -
` DebugHandlerBase - b be - be - be
` BTFDebug - e - - - - b
` CodeViewDebug - be - - - - b
` DWARFDebug yes be - - - - b
Doing virtual function calls per instruction is costly and useless when
the called function does nothing.
This commit performs the following clean-up/improvements:
- PseudoProbeHandler is no longer an AsmPrinterHandler -- it used
nothing of its functionality to hook in at the possible points. This
avoids virtual function calls when a pseudo probe printer is present.
- DebugHandlerBase is no longer an AsmPrinterHandler, but a separate
base class. DebugHandlerBase is the only remaining "hook" for begin/end
instruction and setSymbolSize (only used by DWARFDebug). begin/end for
function and basic block sections are never overriden and therefore are
no longer virtual. (Originally I intended there to be only one debug
handler, but BPF as the only target supports two at the same time: DWARF
and BTF.)
- AsmPrinterHandler no longer has begin/end instruction and
setSymbolSize hooks -- these were only used by DebugHandlerBase. This
avoid iterating over handlers in every instruction.
AsmPrinterHandler Mod Fn mFE BBS FL
` WinCFGuard e e - - -
` EHStreamer - - - - -
` DwarfCFIException e be - be -
` ARMException - be e - -
` AIXException - e - - -
` WinException e be e - be
` WasmException e be - - -
SymSz Mod Fn BBS Inst
DebugHandlerBase - b be be be
` BTFDebug - e b
` CodeViewDebug - be b
` DWARFDebug yes be b
PseudoProbeHandler (no shared methods)
To continue allowing external users (e.g., Julia) to hook in at every
instruction, a new method addDebugHandler is exposed.
This results in a performance improvement, especially in the -O0 -g0
case with unwind information (e.g., JIT baseline).
Summary:
The `errno` variable is expected to be `thread_local` by the standard.
However, the GPU targets do not support `thread_local` and implementing
that would be a large endeavor. Because of that, we previously didn't
provide the `errno` symbol at all. However, to build some programs we at
least need to be able to link against `errno`. Many things that would
normally set `errno` completely ignore it currently (i.e. stdio) but
some programs still need to be able to link against correct C programs.
For this purpose this patch exports the `errno` symbol as a simple
global. Internally, this will be updated atomically so it's at least not
racy. Externally, this will be on the user. I've updated the
documentation to state as such. This is required to get `libc++` to
build.
Summary:
Straightforward RPC implementation of the `remove` function for the GPU.
Copies over the string and calls `remove` on it, passing the result
back. This is required for building some `libc++` functionality.
This patch fixes the docs generation for the DLTI dialect to include
attributes (CMake config pointed to the wrong tablegen file). It also
fixes formatting in places so that proper markdown is generated.
