This includes fixes for:
- test-suite: some benchmarks need to be compiled with -fcommon, see D75557.
- compiler-rt: one test needed -fcommon, and another a change, see D75520.
As part of this, set down the general rules for non-trivial types
in C in their full and gory detail, and then separately describe how
they apply to the ARC qualified types.
I'm not totally satisfied with the drafting of the dynamic-objects UB
rules here, but I feel like I'm building on a lot of wreckage.
Summary:
This is an attempt to simply the process of building the clang
documentation, which should help avoid some of the recent issues we've
had generating the documentation for the website.
The html documentation for clang is generated by sphinx from the
reStructuredText (rst) files we have in the clang/docs directory.
There are also some rst files that need to be generated by TableGen,
before they can be passed to sphinx. Prior to this patch we were not
generating those rst files as part with the build system and they had to be
generated manually.
This patch enables the automatic generation of these rst files, but
since they are generated at build time the cannot be placed in the
clang/docs directory and must go into the cmake build directory.
Unfortunately sphinx does not currently support multiple source
directories[1], so in order to be able to generate the full
documentation, we need to work around this by copying the
rst files from the clang/docs into the build directory before
generating the html documentation.
[1] https://github.com/sphinx-doc/sphinx/issues/3132
Reviewers: rsmith, aaron.ballman, beanz, smeenai, phosek, compnerd, mgorny, delcypher
Reviewed By: mgorny, delcypher
Subscribers: delcypher, merge_guards_bot, mgorny, llvm-commits, cfe-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D72875
Summary:
Currently, `optionally` can take multiple arguments, which commits it to a
particular strategy for those arguments (in this case, "for each"). We limit the
matcher to a single argument, which avoids any potential confusion and
simplifies the implementation. The user can retrieve multiple-argument
optionality, by explicitly using the desired operator (like `forEach`, `anyOf`,
`allOf`, etc.) with all children wrapped in `optionally`.
Reviewers: sbenza, aaron.ballman
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D75556
Summary:
This patch introduces the `clang_analyzer_isTainted` expression inspection
check for checking taint.
Using this we could query the analyzer whether the expression used as the
argument is tainted or not. This would be useful in tests, where we don't want
to issue warning for all tainted expressions in a given file
(like the `debug.TaintTest` would do) but only for certain expressions.
Example usage:
```lang=c++
int read_integer() {
int n;
clang_analyzer_isTainted(n); // expected-warning{{NO}}
scanf("%d", &n);
clang_analyzer_isTainted(n); // expected-warning{{YES}}
clang_analyzer_isTainted(n + 2); // expected-warning{{YES}}
clang_analyzer_isTainted(n > 0); // expected-warning{{YES}}
int next_tainted_value = n; // no-warning
return n;
}
```
Reviewers: NoQ, Szelethus, baloghadamsoftware, xazax.hun, boga95
Reviewed By: Szelethus
Subscribers: martong, rnkovacs, whisperity, xazax.hun,
baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, donat.nagy,
Charusso, cfe-commits, boga95, dkrupp, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D74131
This reverts commit 0a9fc9233e.
Going to look at the asan failures.
I find the failures in the test suite weird, because they look
like compile time test and I don't understand how that can be
failing, but will have a brief look at that too.
This makes -fno-common the default for all targets because this has performance
and code-size benefits and is more language conforming for C code.
Additionally, GCC10 also defaults to -fno-common and so we get consistent
behaviour with GCC.
With this change, C code that uses tentative definitions as definitions of a
variable in multiple translation units will trigger multiple-definition linker
errors. Generally, this occurs when the use of the extern keyword is neglected
in the declaration of a variable in a header file. In some cases, no specific
translation unit provides a definition of the variable. The previous behavior
can be restored by specifying -fcommon.
As GCC has switched already, we benefit from applications already being ported
and existing documentation how to do this. For example:
- https://gcc.gnu.org/gcc-10/porting_to.html
- https://wiki.gentoo.org/wiki/Gcc_10_porting_notes/fno_common
Differential revision: https://reviews.llvm.org/D75056
Summary:
Acts on `BinaryOperator` and `UnaryOperator` and functions the same as `anyOf(hasOperatorName(...), hasOperatorName(...), ...)`
Documentation generation isn't perfect but I feel that the python doc script needs updating for that
Reviewers: aaron.ballman, gribozavr2
Reviewed By: aaron.ballman, gribozavr2
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D75040
Summary:
Clang's "asm goto" feature didn't initially support outputs constraints. That
was the same behavior as gcc's implementation. The decision by gcc not to
support outputs was based on a restriction in their IR regarding terminators.
LLVM doesn't restrict terminators from returning values (e.g. 'invoke'), so
it made sense to support this feature.
Output values are valid only on the 'fallthrough' path. If an output value's used
on an indirect branch, then it's 'poisoned'.
In theory, outputs *could* be valid on the 'indirect' paths, but it's very
difficult to guarantee that the original semantics would be retained. E.g.
because indirect labels could be used as data, we wouldn't be able to split
critical edges in situations where two 'callbr' instructions have the same
indirect label, because the indirect branch's destination would no longer be
the same.
Reviewers: jyknight, nickdesaulniers, hfinkel
Reviewed By: jyknight, nickdesaulniers
Subscribers: MaskRay, rsmith, hiraditya, llvm-commits, cfe-commits, craig.topper, rnk
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D69876
Summary:
This patch introduces a new checker:
`alpha.security.cert.pos.34c`
This checker is implemented based on the following rule:
https://wiki.sei.cmu.edu/confluence/x/6NYxBQ
The check warns if `putenv` function is
called with automatic storage variable as an argument.
Differential Revision: https://reviews.llvm.org/D71433
user interface and documentation, and update __cplusplus for C++20.
WG21 considers the C++20 standard to be finished (even though it still
has some more steps to pass through in the ISO process).
The old flag names are accepted for compatibility, as usual, and we
still have lots of references to C++2a in comments and identifiers;
those can be cleaned up separately.
Change clang option -ffp-model=precise, the default, to select ffp-contract=on
The patch caused some problems for PowerPC but ibm has made
adjustments so I am resubmitting this patch. Additionally, Andy looked
at the performance regressions on LNT and it looks like a loop
unrolling decision that could be adjusted.
Reviewers: rjmccall, Andy Kaylor
Differential Revision: https://reviews.llvm.org/D74436
Converting a pointer to an integer whose result cannot represented in the
integer type is undefined behavior is C and prohibited in C++. C++ already
has a diagnostic when casting. This adds a diagnostic for C.
Since this diagnostic uses the range of the conversion it also modifies
int-to-pointer-cast diagnostic to use a range.
Fixes PR8718: No warning on casting between pointer and non-pointer-sized int
Differential Revision: https://reviews.llvm.org/D72231
This reverts commit 0a1123eb43.
Want to revert this because it's causing trouble for PowerPC
I also fixed test fp-model.c which was looking for an incorrect error message
This option add a line break then a lambda is inside a function call.
Reviewers : djasper, klimek, krasimir, MyDeveloperDay
Reviewed By: MyDeveloperDay
Differential Revision: https://reviews.llvm.org/D44609
DynTypedNode and ASTNodeKind are implemented as part of the clang AST
library, which uses the main clang namespace. There doesn't seem to be a
need for this extra level of namespacing.
I left behind aliases in the ast_type_traits namespace for out of tree
clients of these APIs. To provide aliases for the enumerators, I used
this pattern:
namespace ast_type_traits {
constexpr TraversalKind TK_AsIs = ::clang::TK_AsIs;
}
I think the typedefs will be useful for migration, but we might be able
to drop these enumerator aliases.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D74499
This reverts commit 99c5bcbce8.
Change clang option -ffp-model=precise to select ffp-contract=on
Including some small touch-ups to the original commit
Reviewers: rjmccall, Andy Kaylor
Differential Revision: https://reviews.llvm.org/D74436
Implement protection against the stack clash attack [0] through inline stack
probing.
Probe stack allocation every PAGE_SIZE during frame lowering or dynamic
allocation to make sure the page guard, if any, is touched when touching the
stack, in a similar manner to GCC[1].
This extends the existing `probe-stack' mechanism with a special value `inline-asm'.
Technically the former uses function call before stack allocation while this
patch provides inlined stack probes and chunk allocation.
Only implemented for x86.
[0] https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt
[1] https://gcc.gnu.org/ml/gcc-patches/2017-07/msg00556.html
This a recommit of 39f50da2a3 with proper LiveIn
declaration, better option handling and more portable testing.
Differential Revision: https://reviews.llvm.org/D68720
Implement protection against the stack clash attack [0] through inline stack
probing.
Probe stack allocation every PAGE_SIZE during frame lowering or dynamic
allocation to make sure the page guard, if any, is touched when touching the
stack, in a similar manner to GCC[1].
This extends the existing `probe-stack' mechanism with a special value `inline-asm'.
Technically the former uses function call before stack allocation while this
patch provides inlined stack probes and chunk allocation.
Only implemented for x86.
[0] https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt
[1] https://gcc.gnu.org/ml/gcc-patches/2017-07/msg00556.html
This a recommit of 39f50da2a3 with proper LiveIn
declaration, better option handling and more portable testing.
Differential Revision: https://reviews.llvm.org/D68720
Implement protection against the stack clash attack [0] through inline stack
probing.
Probe stack allocation every PAGE_SIZE during frame lowering or dynamic
allocation to make sure the page guard, if any, is touched when touching the
stack, in a similar manner to GCC[1].
This extends the existing `probe-stack' mechanism with a special value `inline-asm'.
Technically the former uses function call before stack allocation while this
patch provides inlined stack probes and chunk allocation.
Only implemented for x86.
[0] https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt
[1] https://gcc.gnu.org/ml/gcc-patches/2017-07/msg00556.html
This a recommit of 39f50da2a3 with better option
handling and more portable testing
Differential Revision: https://reviews.llvm.org/D68720
Summary:
Due to a recent (but retroactive) C++ rule change, only sufficiently
C-compatible classes are permitted to be given a typedef name for
linkage purposes. Add an enabled-by-default warning for these cases, and
rephrase our existing error for the case where we encounter the typedef
name for linkage after we've already computed and used a wrong linkage
in terms of the new rule.
Reviewers: rjmccall
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D74103
Implement protection against the stack clash attack [0] through inline stack
probing.
Probe stack allocation every PAGE_SIZE during frame lowering or dynamic
allocation to make sure the page guard, if any, is touched when touching the
stack, in a similar manner to GCC[1].
This extends the existing `probe-stack' mechanism with a special value `inline-asm'.
Technically the former uses function call before stack allocation while this
patch provides inlined stack probes and chunk allocation.
Only implemented for x86.
[0] https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt
[1] https://gcc.gnu.org/ml/gcc-patches/2017-07/msg00556.html
This a recommit of 39f50da2a3 with correct option
flags set.
Differential Revision: https://reviews.llvm.org/D68720
This reverts commit 39f50da2a3.
The -fstack-clash-protection is being passed to the linker too, which
is not intended.
Reverting and fixing that in a later commit.
Implement protection against the stack clash attack [0] through inline stack
probing.
Probe stack allocation every PAGE_SIZE during frame lowering or dynamic
allocation to make sure the page guard, if any, is touched when touching the
stack, in a similar manner to GCC[1].
This extends the existing `probe-stack' mechanism with a special value `inline-asm'.
Technically the former uses function call before stack allocation while this
patch provides inlined stack probes and chunk allocation.
Only implemented for x86.
[0] https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt
[1] https://gcc.gnu.org/ml/gcc-patches/2017-07/msg00556.html
Differential Revision: https://reviews.llvm.org/D68720
Summary:
From `clang-format` version 3.7.0 and up, , there is no way to keep following format of ObjectiveC block:
```
- (void)_aMethod
{
[self.test1 t:self w:self callback:^(typeof(self) self, NSNumber *u, NSNumber *v) {
u = c;
}]
}
```
Regardless of the change in `.clang-format` configuration file, all parameters will be lined up so that colons will be on the same column, like following:
```
- (void)_aMethod
{
[self.test1 t:self
w:self
callback:^(typeof(self) self, NSNumber *u, NSNumber *v) {
u = c;
}]
}
```
Considering with ObjectiveC, the first code style is cleaner & more readable for some people, I've added a config option: `ObjCDontBreakBeforeNestedBlockParam` (boolean) so that if it is enable, the first code style will be favored.
Reviewed By: MyDeveloperDay
Patch By: ghvg1313
Tags: #clang, #clang-format
Differential Revision: https://reviews.llvm.org/D70926
First attempt at implementing -fsemantic-interposition.
Rely on GlobalValue::isInterposable that already captures most of the expected
behavior.
Rely on a ModuleFlag to state whether we should respect SemanticInterposition or
not. The default remains no.
So this should be a no-op if -fsemantic-interposition isn't used, and if it is,
isInterposable being already used in most optimisation, they should honor it
properly.
Note that it only impacts architecture compiled with -fPIC and no pie.
Differential Revision: https://reviews.llvm.org/D72829
Summary:
Ninja is no longer an experimental tool, documentation changed to
reflect this.
Reviewers: nikola
Reviewed By: nikola
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D73567
This patch broke the Sanitizer buildbots. Please see the commit's
differential revision for more information
(https://reviews.llvm.org/D67678).
This reverts commit b72a8c65e4.
Summary:
The documentation for IndentCaseLabels claimed that the "Switch
statement body is always indented one level more than case labels". This
is technically false for the code block immediately following the label.
Its closing bracket aligns with the start of the label.
If the case label are not indented, it leads to a style where the
closing bracket of the block aligns with the closing bracket of the
switch statement, which can be hard to parse.
This change introduces a new option, IndentCaseBlocks, which when true
treats the block as a scope block (which it technically is).
(Note: regenerated ClangFormatStyleOptions.rst using tools/dump_style.py)
Reviewed By: MyDeveloperDay
Patch By: capn
Tags: #clang-format, #clang
Differential Revision: https://reviews.llvm.org/D72276
This is an alternative to the continous mode that was implemented in
D68351. This mode relies on padding and the ability to mmap a file over
the existing mapping which is generally only available on POSIX systems
and isn't suitable for other platforms.
This change instead introduces the ability to relocate counters at
runtime using a level of indirection. On every counter access, we add a
bias to the counter address. This bias is stored in a symbol that's
provided by the profile runtime and is initially set to zero, meaning no
relocation. The runtime can mmap the profile into memory at abitrary
location, and set bias to the offset between the original and the new
counter location, at which point every subsequent counter access will be
to the new location, which allows updating profile directly akin to the
continous mode.
The advantage of this implementation is that doesn't require any special
OS support. The disadvantage is the extra overhead due to additional
instructions required for each counter access (overhead both in terms of
binary size and performance) plus duplication of counters (i.e. one copy
in the binary itself and another copy that's mmapped).
Differential Revision: https://reviews.llvm.org/D69740
Flags are clang's default UI is flags.
We can have an env var in addition to that, but in D69825 nobody has yet
mentioned why this needs an env var, so omit it for now. If someone
needs to set the flag via env var, the existing CCC_OVERRIDE_OPTIONS
mechanism works for it (set CCC_OVERRIDE_OPTIONS=+-fno-integrated-cc1
for example).
Also mention the cc1-in-process change in the release notes.
Also spruce up the test a bit so it actually tests something :)
Differential Revision: https://reviews.llvm.org/D72769
GCC supports the conditional operator on VectorTypes that acts as a
'select' in C++ mode. This patch implements the support. Types are
converted as closely to GCC's behavior as possible, though in a few
places consistency with our existing vector type support was preferred.
Note that this implementation is different from the OpenCL version in a
number of ways, so it unfortunately required a different implementation.
First, the SEMA rules and promotion rules are significantly different.
Secondly, GCC implements COND[i] != 0 ? LHS[i] : RHS[i] (where i is in
the range 0- VectorSize, for each element). In OpenCL, the condition is
COND[i] < 0 ? LHS[i]: RHS[i].
In the process of implementing this, it was also required to make the
expression COND ? LHS : RHS type dependent if COND is type dependent,
since the type is now dependent on the condition. For example:
T ? 1 : 2;
Is not typically type dependent, since the result can be deduced from
the operands. HOWEVER, if T is a VectorType now, it could change this
to a 'select' (basically a swizzle with a non-constant mask) with the 1
and 2 being promoted to vectors themselves.
While this is a change, it is NOT a standards incompatible change. Based
on my (and D. Gregor's, at the time of writing the code) reading of the
standard, the expression is supposed to be type dependent if ANY
sub-expression is type dependent.
Differential Revision: https://reviews.llvm.org/D71463
Summary:
The analysis for const-ness of local variables required a view generally useful
matchers that are extracted into its own patch.
They are `decompositionDecl` and `forEachArgumentWithParamType`, that works
for calls through function pointers as well.
Reviewers: aaron.ballman
Reviewed By: aaron.ballman
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D72505
Summary:
This checker verifies if default placement new is provided with pointers
to sufficient storage capacity.
Noncompliant Code Example:
#include <new>
void f() {
short s;
long *lp = ::new (&s) long;
}
Based on SEI CERT rule MEM54-CPP
https://wiki.sei.cmu.edu/confluence/display/cplusplus/MEM54-CPP.+Provide+placement+new+with+properly+aligned+pointe
This patch does not implement checking of the alignment.
Reviewers: NoQ, xazax.hun
Subscribers: mgorny, whisperity, xazax.hun, baloghadamsoftware, szepet,
rnkovacs, a.sidorin, mikhail.ramalho, donat
Tags: #clang
Differential Revision: https://reviews.llvm.org/D71612
This change introduces three new builtins (which work on both pointers
and integers) that can be used instead of common bitwise arithmetic:
__builtin_align_up(x, alignment), __builtin_align_down(x, alignment) and
__builtin_is_aligned(x, alignment).
I originally added these builtins to the CHERI fork of LLVM a few years ago
to handle the slightly different C semantics that we use for CHERI [1].
Until recently these builtins (or sequences of other builtins) were
required to generate correct code. I have since made changes to the default
C semantics so that they are no longer strictly necessary (but using them
does generate slightly more efficient code). However, based on our experience
using them in various projects over the past few years, I believe that adding
these builtins to clang would be useful.
These builtins have the following benefit over bit-manipulation and casts
via uintptr_t:
- The named builtins clearly convey the semantics of the operation. While
checking alignment using __builtin_is_aligned(x, 16) versus
((x & 15) == 0) is probably not a huge win in readably, I personally find
__builtin_align_up(x, N) a lot easier to read than (x+(N-1))&~(N-1).
- They preserve the type of the argument (including const qualifiers). When
using casts via uintptr_t, it is easy to cast to the wrong type or strip
qualifiers such as const.
- If the alignment argument is a constant value, clang can check that it is
a power-of-two and within the range of the type. Since the semantics of
these builtins is well defined compared to arbitrary bit-manipulation,
it is possible to add a UBSAN checker that the run-time value is a valid
power-of-two. I intend to add this as a follow-up to this change.
- The builtins avoids int-to-pointer casts both in C and LLVM IR.
In the future (i.e. once most optimizations handle it), we could use the new
llvm.ptrmask intrinsic to avoid the ptrtoint instruction that would normally
be generated.
- They can be used to round up/down to the next aligned value for both
integers and pointers without requiring two separate macros.
- In many projects the alignment operations are already wrapped in macros (e.g.
roundup2 and rounddown2 in FreeBSD), so by replacing the macro implementation
with a builtin call, we get improved diagnostics for many call-sites while
only having to change a few lines.
- Finally, the builtins also emit assume_aligned metadata when used on pointers.
This can improve code generation compared to the uintptr_t casts.
[1] In our CHERI compiler we have compilation mode where all pointers are
implemented as capabilities (essentially unforgeable 128-bit fat pointers).
In our original model, casts from uintptr_t (which is a 128-bit capability)
to an integer value returned the "offset" of the capability (i.e. the
difference between the virtual address and the base of the allocation).
This causes problems for cases such as checking the alignment: for example, the
expression `if ((uintptr_t)ptr & 63) == 0` is generally used to check if the
pointer is aligned to a multiple of 64 bytes. The problem with offsets is that
any pointer to the beginning of an allocation will have an offset of zero, so
this check always succeeds in that case (even if the address is not correctly
aligned). The same issues also exist when aligning up or down. Using the
alignment builtins ensures that the address is used instead of the offset. While
I have since changed the default C semantics to return the address instead of
the offset when casting, this offset compilation mode can still be used by
passing a command-line flag.
Reviewers: rsmith, aaron.ballman, theraven, fhahn, lebedev.ri, nlopes, aqjune
Reviewed By: aaron.ballman, lebedev.ri
Differential Revision: https://reviews.llvm.org/D71499
Summary: Pretty self-evident. This example was missing an lparen. Added it, and fixed up the ASCII art.
Patch by Nick Black <dankamongmen@gmail.com>
Reviewers: pcc
Reviewed By: pcc
Subscribers: tejohnson, mehdi_amini, inglorion, hiraditya, steven_wu, dexonsmith, cfe-commits
Tags: #llvm, #clang
Differential Revision: https://reviews.llvm.org/D70765
This matcher matches any node and at the same time executes all its
inner matchers to produce any possbile result bindings.
This is useful when a user wants certain supplementary information
that's not always present along with the main match result.
Remove description of language mode from the language
extensions and add a link to pdf document.
Tags: #clang
Differential Revision: https://reviews.llvm.org/D72076
Adds a new ASTMatcher condition called 'hasInitStatement()' that matches if,
switch and range-for statements with an initializer. Reworked clang-tidy
readability-else-after-return to handle variables in the if condition or init
statements in c++17 ifs. Also checks if removing the else would affect object
lifetimes in the else branch.
Fixes PR44364.
On Darwin, when used for generating a linked binary from a source file
(through an intermediate object file), the driver will invoke `cc1` to
generate a temporary object file. The temporary remark file will now be
emitted next to the object file, which will then be picked up by
`dsymutil` and emitted in the .dSYM bundle.
This is available for all formats except YAML since by default, YAML
doesn't need a section and the remark file will be lost.
D39317 made clang use .init_array when no gcc installations is found.
This change changes all gcc installations to use .init_array .
GCC 4.7 by default stopped providing .ctors/.dtors compatible crt files,
and stopped emitting .ctors for __attribute__((constructor)).
.init_array should always work.
FreeBSD rules are moved to FreeBSD.cpp to make Generic_ELF rules clean.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D71434
Copy the block to the heap before passing it to the callee in case the
block escapes in the callee.
rdar://problem/55683462
Differential Revision: https://reviews.llvm.org/D71431
This adds a check for the usage of -foptimization-record-file with
multiple -arch options. This is not permitted since it would require us
to rename the file requested by the user to avoid overwriting it for the
second cc1 invocation.
Patch was reverted because https://bugs.llvm.org/show_bug.cgi?id=44048
The original patch is modified to set the strictfp IR attribute
explicitly in CodeGen instead of as a side effect of IRBuilder.
In the 2nd attempt to reapply there was a windows lit test fail, the
tests were fixed to use wildcard matching.
Differential Revision: https://reviews.llvm.org/D62731
Emit a gap region beginning where the switch body begins. This sets line
execution counts in the areas between non-overlapping cases to 0.
This also removes some special handling of the first case in a switch:
these are now treated like any other case.
This does not resolve an outstanding issue with case statement regions
that do not end when a region is terminated. But it should address
llvm.org/PR44011.
Differential Revision: https://reviews.llvm.org/D70571
Summary:
Removed the ```-fforce-experimental-new-constant-interpreter flag```, leaving
only the ```-fexperimental-new-constant-interpreter``` one. The interpreter
now always emits an error on an unsupported feature.
Allowing the interpreter to bail out would require a mapping from APValue to
interpreter memory, which will not be necessary in the final version. It is
more sensible to always emit an error if the interpreter fails.
Reviewers: jfb, Bigcheese, rsmith, dexonsmith
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D70071
Summary:
Implicit Conversion Sanitizer is *almost* feature complete.
There aren't *that* much unsanitized things left,
two major ones are increment/decrement (this patch) and bit fields.
As it was discussed in
[[ https://bugs.llvm.org/show_bug.cgi?id=39519 | PR39519 ]],
unlike `CompoundAssignOperator` (which is promoted internally),
or `BinaryOperator` (for which we always have promotion/demotion in AST)
or parts of `UnaryOperator` (we have promotion/demotion but only for
certain operations), for inc/dec, clang omits promotion/demotion
altogether, under as-if rule.
This is technically correct: https://rise4fun.com/Alive/zPgD
As it can be seen in `InstCombineCasts.cpp` `canEvaluateTruncated()`,
`add`/`sub`/`mul`/`and`/`or`/`xor` operators can all arbitrarily
be extended or truncated:
901cd3b3f6/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp (L1320-L1334)
But that has serious implications:
1. Since we no longer model implicit casts, do we pessimise
their AST representation and everything that uses it?
2. There is no demotion, so lossy demotion sanitizer does not trigger :]
Now, i'm not going to argue about the first problem here,
but the second one **needs** to be addressed. As it was stated
in the report, this is done intentionally, so changing
this in all modes would be considered a penalization/regression.
Which means, the sanitization-less codegen must not be altered.
It was also suggested to not change the sanitized codegen
to the one with demotion, but i quite strongly believe
that will not be the wise choice here:
1. One will need to re-engineer the check that the inc/dec was lossy
in terms of `@llvm.{u,s}{add,sub}.with.overflow` builtins
2. We will still need to compute the result we would lossily demote.
(i.e. the result of wide `add`ition/`sub`traction)
3. I suspect it would need to be done right here, in sanitization.
Which kinda defeats the point of
using `@llvm.{u,s}{add,sub}.with.overflow` builtins:
we'd have two `add`s with basically the same arguments,
one of which is used for check+error-less codepath and other one
for the error reporting. That seems worse than a single wide op+check.
4. OR, we would need to do that in the compiler-rt handler.
Which means we'll need a whole new handler.
But then what about the `CompoundAssignOperator`,
it would also be applicable for it.
So this also doesn't really seem like the right path to me.
5. At least X86 (but likely others) pessimizes all sub-`i32` operations
(due to partial register stalls), so even if we avoid promotion+demotion,
the computations will //likely// be performed in `i32` anyways.
So i'm not really seeing much benefit of
not doing the straight-forward thing.
While looking into this, i have noticed a few more LLVM middle-end
missed canonicalizations, and filed
[[ https://bugs.llvm.org/show_bug.cgi?id=44100 | PR44100 ]],
[[ https://bugs.llvm.org/show_bug.cgi?id=44102 | PR44102 ]].
Those are not specific to inc/dec, we also have them for
`CompoundAssignOperator`, and it can happen for normal arithmetics, too.
But if we take some other path in the patch, it will not be applicable
here, and we will have most likely played ourselves.
TLDR: front-end should emit canonical, easy-to-optimize yet
un-optimized code. It is middle-end's job to make it optimal.
I'm really hoping reviewers agree with my personal assessment
of the path this patch should take..
This originally landed in 9872ea4ed1
but got immediately reverted in cbfa237892
because the assertion was faulty. That fault ended up being caused
by the enum - while there will be promotion, both types are unsigned,
with same width. So we still don't need to sanitize non-signed cases.
So far. Maybe the assert will tell us this isn't so.
Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=44054 | PR44054 ]].
Refs. https://github.com/google/sanitizers/issues/940
Reviewers: rjmccall, erichkeane, rsmith, vsk
Reviewed By: erichkeane
Subscribers: mehdi_amini, dexonsmith, cfe-commits, #sanitizers, llvm-commits, aaron.ballman, t.p.northover, efriedma, regehr
Tags: #llvm, #clang, #sanitizers
Differential Revision: https://reviews.llvm.org/D70539
The asssertion that was added does not hold,
breaks on test-suite/MultiSource/Applications/SPASS/analyze.c
Will reduce the testcase and revisit.
This reverts commit 9872ea4ed1, 870f3542d3.
Summary:
Implicit Conversion Sanitizer is *almost* feature complete.
There aren't *that* much unsanitized things left,
two major ones are increment/decrement (this patch) and bit fields.
As it was discussed in
[[ https://bugs.llvm.org/show_bug.cgi?id=39519 | PR39519 ]],
unlike `CompoundAssignOperator` (which is promoted internally),
or `BinaryOperator` (for which we always have promotion/demotion in AST)
or parts of `UnaryOperator` (we have promotion/demotion but only for
certain operations), for inc/dec, clang omits promotion/demotion
altogether, under as-if rule.
This is technically correct: https://rise4fun.com/Alive/zPgD
As it can be seen in `InstCombineCasts.cpp` `canEvaluateTruncated()`,
`add`/`sub`/`mul`/`and`/`or`/`xor` operators can all arbitrarily
be extended or truncated:
901cd3b3f6/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp (L1320-L1334)
But that has serious implications:
1. Since we no longer model implicit casts, do we pessimise
their AST representation and everything that uses it?
2. There is no demotion, so lossy demotion sanitizer does not trigger :]
Now, i'm not going to argue about the first problem here,
but the second one **needs** to be addressed. As it was stated
in the report, this is done intentionally, so changing
this in all modes would be considered a penalization/regression.
Which means, the sanitization-less codegen must not be altered.
It was also suggested to not change the sanitized codegen
to the one with demotion, but i quite strongly believe
that will not be the wise choice here:
1. One will need to re-engineer the check that the inc/dec was lossy
in terms of `@llvm.{u,s}{add,sub}.with.overflow` builtins
2. We will still need to compute the result we would lossily demote.
(i.e. the result of wide `add`ition/`sub`traction)
3. I suspect it would need to be done right here, in sanitization.
Which kinda defeats the point of
using `@llvm.{u,s}{add,sub}.with.overflow` builtins:
we'd have two `add`s with basically the same arguments,
one of which is used for check+error-less codepath and other one
for the error reporting. That seems worse than a single wide op+check.
4. OR, we would need to do that in the compiler-rt handler.
Which means we'll need a whole new handler.
But then what about the `CompoundAssignOperator`,
it would also be applicable for it.
So this also doesn't really seem like the right path to me.
5. At least X86 (but likely others) pessimizes all sub-`i32` operations
(due to partial register stalls), so even if we avoid promotion+demotion,
the computations will //likely// be performed in `i32` anyways.
So i'm not really seeing much benefit of
not doing the straight-forward thing.
While looking into this, i have noticed a few more LLVM middle-end
missed canonicalizations, and filed
[[ https://bugs.llvm.org/show_bug.cgi?id=44100 | PR44100 ]],
[[ https://bugs.llvm.org/show_bug.cgi?id=44102 | PR44102 ]].
Those are not specific to inc/dec, we also have them for
`CompoundAssignOperator`, and it can happen for normal arithmetics, too.
But if we take some other path in the patch, it will not be applicable
here, and we will have most likely played ourselves.
TLDR: front-end should emit canonical, easy-to-optimize yet
un-optimized code. It is middle-end's job to make it optimal.
I'm really hoping reviewers agree with my personal assessment
of the path this patch should take..
Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=44054 | PR44054 ]].
Reviewers: rjmccall, erichkeane, rsmith, vsk
Reviewed By: erichkeane
Subscribers: mehdi_amini, dexonsmith, cfe-commits, #sanitizers, llvm-commits, aaron.ballman, t.p.northover, efriedma, regehr
Tags: #llvm, #clang, #sanitizers
Differential Revision: https://reviews.llvm.org/D70539
We seem to have been gradually growing support for atomic min/max operations
(exposing longstanding IR atomicrmw instructions). But until now there have
been gaps in the expected intrinsics. This adds support for the C11-style
intrinsics (i.e. taking _Atomic, rather than individually blessed by C11
standard), and the variants that return the new value instead of the original
one.
That way, people won't be misled by trying one form and it not working, and the
front-end is more friendly to people using _Atomic types, as we recommend.
Make it possible to use online profile merging ("%m" mode) with
continuous sync ("%c" mode).
To implement this, the merged profile is locked in the runtime
initialization step and either a) filled out for the first time or b)
checked for compatibility. Then, the profile can simply be mmap()'d with
MAP_SHARED set. With the mmap() in place, counter updates from every
process which uses an image are mapped onto the same set of physical
pages assigned by the filesystem cache. After the mmap() is set up, the
profile is unlocked.
Differential Revision: https://reviews.llvm.org/D69586
and a follow-up NFC rearrangement as it's causing a crash on valid. Testcase is on the original review thread.
This reverts commits af57dbf12e and e6584b2b7b
For RISC-V the value provided to -march should determine whether to
compile for 32- or 64-bit RISC-V irrespective of the target provided to
the Clang driver. This adds a test for this flag for RISC-V and sets the
Target architecture correctly in these cases.
Differential Revision: https://reviews.llvm.org/D54214
Provides support for using r6-r11 as globally scoped
register variables. This requires a -ffixed-rN flag
in order to reserve rN against general allocation.
If for a given GRV declaration the corresponding flag
is not found, or the the register in question is the
target's FP, we fail with a diagnostic.
Differential Revision: https://reviews.llvm.org/D68862
Summary: Adds a new option SpaceBeforeBrackets to add spaces before brackets (i.e. int a[23]; -> int a [23];) This is present as an option in the Visual Studio C++ code formatting settings, but there was no matching setting in clang-format.
Reviewers: djasper, MyDeveloperDay, mitchell-stellar
Reviewed By: MyDeveloperDay
Subscribers: llvm-commits, cfe-commits, klimek
Patch by: Anteru
Tags: #clang, #clang-format, #llvm
Differential Revision: https://reviews.llvm.org/D6920
Summary:
Clang/LLVM is a cross-compiler, and so we don't have to make a choice
about `-march`/`-mabi` at build-time, but we may have to compute a
default `-march`/`-mabi` when compiling a program. Until now, each
place that has needed a default `-march` has calculated one itself.
This patch adds a single place where a default `-march` is calculated,
in order to avoid calculating different defaults in different places.
This patch adds a new function `riscv::getRISCVArch` which encapsulates
this logic based on GCC's for computing a default `-march` value
when none is provided. This patch also updates the logic in
`riscv::getRISCVABI` to match the logic in GCC's build system for
computing a default `-mabi`.
This patch also updates anywhere that `-march` is used to now use the
new function which can compute a default. In particular, we now
explicitly pass a `-march` value down to the gnu assembler.
GCC has convoluted logic in its build system to choose a default
`-march`/`-mabi` based on build options, which would be good to match.
This patch is based on the logic in GCC 9.2.0. This commit's logic is
different to GCC's only for baremetal targets, where we default
to rv32imac/ilp32 or rv64imac/lp64 depending on the target triple.
Tests have been updated to match the new logic.
Reviewers: asb, luismarques, rogfer01, kito-cheng, khchen
Reviewed By: asb, luismarques
Subscribers: sameer.abuasal, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, shiva0217, jrtc27, MaskRay, zzheng, edward-jones, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, Jim, s.egerton, pzheng, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D69383
Summary:
By additional regex match, grouping of main include can be enabled in files that are not normally considered as a C/C++ source code.
For example, this might be useful in templated code, where template implementations are being held in *Impl.hpp files.
On the occassion, 'assume-filename' option description was reworded as it was misleading. It has nothing to do with `style=file` option and it does not influence sourced style filename.
Reviewers: rsmith, ioeric, krasimir, sylvestre.ledru, MyDeveloperDay
Reviewed By: MyDeveloperDay
Subscribers: MyDeveloperDay, cfe-commits
Patch by: furdyna
Tags: #clang
Differential Revision: https://reviews.llvm.org/D67750
Summary:
Format.h is used to generate ClangFormatStyleOptions.rst, the layout of the comments is critical to the rst file. Accidentally clang-formatting Format.h can lead to the .rst changing.
This revision simply add // clang-format off/on statement around the areas who formatting needs to be maintained, mainly around the options that are related to what happens when the line breaks due to `ColumnLimit` (which is what is happening to the comment)
This allows Format.h to be clang-formatted without causing a change in the documentation when dump_format_style.py is rerun, which is also part of the revision.
Reviewers: mitchell-stellar, klimek, sammccall, owenpan
Reviewed By: mitchell-stellar
Subscribers: cfe-commits
Tags: #clang, #clang-format
Differential Revision: https://reviews.llvm.org/D69951
Summary:
This revision is the last in a series of revisions to return `clang/doc/tools/dump_format_style.py` to be being able to parse Format.h without needing to manually merge the ClangFormatStyleOptions.rst file.
The final modification to dump_format_style.py is needed following the addition of a nested enumeration inside a nested structure following the introduction of {D68296}
Prior related revisions will allow for a fully clang-formatted `clang/include/clang/Format/Format.h` to once again be used at the source.
{D69951}
{D69433}
{D69404}
Reviewers: mitchell-stellar, klimek, sammccall, owenpan
Reviewed By: mitchell-stellar
Subscribers: cfe-commits
Tags: #clang-format, #clang
Differential Revision: https://reviews.llvm.org/D70003
Summary: This is updating the OpenMP status table. Cray has volunteered for `defaultmap` and supporting `in_reduction` on the `target` construct, so the status on those entries from was changed from "unclaimed". Also, a new entry was added for supporting non-contiguous arrays sections on the `target update` directive.
Reviewers: ABataev, hfinkel, jdoerfert, kkwli0
Reviewed By: ABataev
Subscribers: guansong, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D69923
Add options to control floating point behavior: trapping and
exception behavior, rounding, and control of optimizations that affect
floating point calculations. More details in UsersManual.rst.
Reviewers: rjmccall
Differential Revision: https://reviews.llvm.org/D62731
Summary:
a change {D67541} cause LanguageStandard to now be subtly different from all other clang-format options, in that the Enum value (less the prefix) is not always allowed as valid as the configuration option.
This caused the ClangFormatStyleOptions.rst and the Format.h to diverge so that the ClangFormatStyleOptions.rst could no longer be generated from the Format.h using dump_format_stlye.py
This fix tried to remedy that:
1) by allowing an additional comment (in Format.h) after the enum to be used as the `in configuration ( XXXX )` text, and changing the dump_format_style.py to support that.
This makes the following code:
```
enum {
...
LS_Cpp03, // c++03
LS_Cpp11, // c++11
...
};
```
would render as:
```* ``LS_Cpp03`` (in configuration: ``c++03``)
* ``LS_Cpp11`` (in configuration: ``c++11``)
```
And we also move the deprecated alias into the text of the enum (otherwise it won't be added at the end as an option)
This patch includes a couple of other whitespace changes which help bring Format.h and ClangFormatStyleOptions.rst almost back into line and regeneratable... (there is still one more)
Reviewers: klimek, mitchell-stellar, sammccall
Reviewed By: mitchell-stellar, sammccall
Subscribers: mrexodia, cfe-commits
Tags: #clang, #clang-format
Differential Revision: https://reviews.llvm.org/D69433
-mvzeroupper will force the vzeroupper insertion pass to run on
CPUs that normally wouldn't. -mno-vzeroupper disables it on CPUs
where it normally runs.
To support this with the default feature handling in clang, we
need a vzeroupper feature flag in X86.td. Since this flag has
the opposite polarity of the fast-partial-ymm-or-zmm-write we
used to use to disable the pass, we now need to add this new
flag to every CPU except KNL/KNM and BTVER2 to keep identical
behavior.
Remove -fast-partial-ymm-or-zmm-write which is no longer used.
Differential Revision: https://reviews.llvm.org/D69786
Add support for continuously syncing profile counter updates to a file.
The motivation for this is that programs do not always exit cleanly. On
iOS, for example, programs are usually killed via a signal from the OS.
Running atexit() handlers after catching a signal is unreliable, so some
method for progressively writing out profile data is necessary.
The approach taken here is to mmap() the `__llvm_prf_cnts` section onto
a raw profile. To do this, the linker must page-align the counter and
data sections, and the runtime must ensure that counters are mapped to a
page-aligned offset within a raw profile.
Continuous mode is (for the moment) incompatible with the online merging
mode. This limitation is lifted in https://reviews.llvm.org/D69586.
Continuous mode is also (for the moment) incompatible with value
profiling, as I'm not sure whether there is interest in this and the
implementation may be tricky.
As I have not been able to test extensively on non-Darwin platforms,
only Darwin support is included for the moment. However, continuous mode
may "just work" without modification on Linux and some UNIX-likes. AIUI
the default value for the GNU linker's `--section-alignment` flag is set
to the page size on many systems. This appears to be true for LLD as
well, as its `no_nmagic` option is on by default. Continuous mode will
not "just work" on Fuchsia or Windows, as it's not possible to mmap() a
section on these platforms. There is a proposal to add a layer of
indirection to the profile instrumentation to support these platforms.
rdar://54210980
Differential Revision: https://reviews.llvm.org/D68351
Removed the explicit list of supported features from OpenMP 5.0 and used
the reference to the table instead. Also, fixed info about constructs
that can be executed in SPMD mode, if and num_threads clauses do not
affect it anymore.
Summary:
A new function pass (Transforms/CFGuard/CFGuard.cpp) inserts CFGuard checks on
indirect function calls, using either the check mechanism (X86, ARM, AArch64) or
or the dispatch mechanism (X86-64). The check mechanism requires a new calling
convention for the supported targets. The dispatch mechanism adds the target as
an operand bundle, which is processed by SelectionDAG. Another pass
(CodeGen/CFGuardLongjmp.cpp) identifies and emits valid longjmp targets, as
required by /guard:cf. This feature is enabled using the `cfguard` CC1 option.
Reviewers: thakis, rnk, theraven, pcc
Subscribers: ychen, hans, metalcanine, dmajor, tomrittervg, alex, mehdi_amini, mgorny, javed.absar, kristof.beyls, hiraditya, steven_wu, dexonsmith, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D65761
Sjoerd Meijer