The lowering looks a lot like normal EH lowering, with the exception
that the exceptions are caught by executing filter expression code
instead of matching typeinfo globals. The filter expressions are
outlined into functions which are used in landingpad clauses where
typeinfo would normally go.
Major aspects that still need work:
- Non-call exceptions in __try bodies won't work yet. The plan is to
outline the __try block in the frontend to keep things simple.
- Filter expressions cannot use local variables until capturing is
implemented.
- __finally blocks will not run after exceptions. Fixing this requires
work in the LLVM SEH preparation pass.
The IR lowering looks like this:
// C code:
bool safe_div(int n, int d, int *r) {
__try {
*r = normal_div(n, d);
} __except(_exception_code() == EXCEPTION_INT_DIVIDE_BY_ZERO) {
return false;
}
return true;
}
; LLVM IR:
define i32 @filter(i8* %e, i8* %fp) {
%ehptrs = bitcast i8* %e to i32**
%ehrec = load i32** %ehptrs
%code = load i32* %ehrec
%matches = icmp eq i32 %code, i32 u0xC0000094
%matches.i32 = zext i1 %matches to i32
ret i32 %matches.i32
}
define i1 zeroext @safe_div(i32 %n, i32 %d, i32* %r) {
%rr = invoke i32 @normal_div(i32 %n, i32 %d)
to label %normal unwind to label %lpad
normal:
store i32 %rr, i32* %r
ret i1 1
lpad:
%ehvals = landingpad {i8*, i32} personality i32 (...)* @__C_specific_handler
catch i8* bitcast (i32 (i8*, i8*)* @filter to i8*)
%ehptr = extractvalue {i8*, i32} %ehvals, i32 0
%sel = extractvalue {i8*, i32} %ehvals, i32 1
%filter_sel = call i32 @llvm.eh.seh.typeid.for(i8* bitcast (i32 (i8*, i8*)* @filter to i8*))
%matches = icmp eq i32 %sel, %filter_sel
br i1 %matches, label %eh.except, label %eh.resume
eh.except:
ret i1 false
eh.resume:
resume
}
Reviewers: rjmccall, rsmith, majnemer
Differential Revision: http://reviews.llvm.org/D5607
llvm-svn: 226760
Sema::ActOnIdExpression to use the new functionality.
Among other things, this allows recovery in several cases where it
wasn't possible before (e.g. correcting a mistyped static_cast<>).
llvm-svn: 222464
Changes diagnostic options, language standard options, diagnostic identifiers, diagnostic wording to use c++14 instead of c++1y. It also modifies related test cases to use the updated diagnostic wording.
llvm-svn: 215982
This patch is necessary to support constant expressions which replaces the integer value in the loop hint attribute with an expression. The integer value was also storing the pragma’s state for options like vectorize(enable/disable) and the pragma unroll and nounroll directive. The state variable is introduced to hold the state of those options/pragmas. This moves the validation of the state (keywords) from SemaStmtAttr handler to the loop hint annotation token handler.
Resubmit with changes to try to fix the build-bot issue.
Reviewed by Aaron Ballman
llvm-svn: 214432
This patch is necessary to support constant expressions which replaces the integer value in the loop hint attribute with an expression. The integer value was also storing the pragma’s state for options like vectorize(enable/disable) and the pragma unroll and nounroll directive. The state variable is introduced to hold the state of those options/pragmas. This moves the validation of the state (keywords) from SemaStmtAttr handler to the loop hint annotation token handler.
Reviewed by Aaron Ballman
llvm-svn: 214333
Assigns indices to try blocks. These indices will used in constructing
tables that the mscrt function __except_handler3 reads during SEH.
Testing will occur once we actually emit the tables, in a subsequent
patch.
llvm-svn: 213437
Give scope a SEHTryScope bit, set that in ParseSEHTry(), and let Sema
walk the scope chain to find the SEHTry parent on __leave statements.
(They are rare enough that it seems better to do the walk instead of
giving Scope a SEHTryParent pointer -- this is similar to AtCatchScope.)
llvm-svn: 212422
Rather than having kw___if_exists be a special case of
ParseCompoundStatementBody, we can look for kw___if_exists in the big
switch over for valid statement tokens in ParseStatementOrDeclaration.
Nested __if_exists blocks are used in the DECLARE_REGISTRY_RESOURCEID
macro from atlcom.h.
llvm-svn: 211654
hint attributes. Includes tests for pragma printing and for attribute order
which is incorrectly reversed by ParsedAttributes.
Reviewed by Aaron Ballman
llvm-svn: 210925
This change isolates various llvm/MC headers from the rest of the parser and
better aligns with the existing SemaStmtAsm.cpp.
No change in functionality, code move only.
llvm-svn: 210420
Parse of nested name spacifier is modified so that it properly recovers
if colon is mistyped as double colon in case statement.
This patch fixes PR15133.
Differential Revision: http://llvm-reviews.chandlerc.com/D2870
llvm-svn: 206135
This patch adds support for the msvc pragmas section, bss_seg, code_seg,
const_seg and data_seg as well as support for __declspec(allocate()).
Additionally it corrects semantics and adds diagnostics for
__attribute__((section())) and the interaction between the attribute
and the msvc pragmas and declspec. In general conflicts should now be
well diganosed within and among these features.
In supporting the pragmas new machinery for uniform lexing for
msvc pragmas was introduced. The new machinery always lexes the
entire pragma and stores it on an annotation token. The parser
is responsible for parsing the pragma when the handling the
annotation token.
There is a known outstanding bug in this implementation in C mode.
Because these attributes and pragmas apply _only_ to definitions, we
process them at the time we detect a definition. Due to tentative
definitions in C, we end up processing the definition late. This means
that in C mode, everything that ends up in a BSS section will end up in
the _last_ BSS section rather than the one that was live at the time of
tentative definition, even if that turns out to be the point of actual
definition. This issue is not known to impact anything as of yet
because we are not aware of a clear use or use case for #pragma bss_seg
but should be fixed at some point.
Differential Revision=http://reviews.llvm.org/D3065#inline-16241
llvm-svn: 205810
When parsing MS inline assembly, we note that fpsw is an implicit def of
most x87 FP operations, and add it to the clobber list. However, we
don't recognize fpsw as a gcc register name, and we assert. Clang
always adds an fpsr clobber, which means the same thing to LLVM, so we
can just use that.
This test case was broken by my LLVM change r196939.
Reviewers: echristo
Differential Revision: http://llvm-reviews.chandlerc.com/D2993
llvm-svn: 204878
Summary:
The MSVC ABI appears to mangle the lexical scope into the names of
statics. Specifically, a counter is incremented whenever a scope is
entered where things can be declared in such a way that an ambiguity can
arise. For example, a class scope inside of a class scope doesn't do
anything interesting because the nested class cannot collide with
another nested class.
There are problems with this scheme:
- It is unreliable. The counter is only incremented when a previously
never encountered scope is entered. There are cases where this will
cause ambiguity amongst declarations that have the same name where one
was introduced in a deep scope while the other was introduced right
after in the previous lexical scope.
- It is wasteful. Statements like: {{{{{{{ static int foo = a; }}}}}}}
will make the mangling of "foo" larger than it need be because the
scope counter has been incremented many times.
Because of these problems, and practical implementation concerns. We
choose not to implement this scheme if the local static or local type
isn't visible. The mangling of these declarations will look very
similar but the numbering will make far more sense, this scheme is
lifted from the Itanium ABI implementation.
Reviewers: rsmith, doug.gregor, rnk, eli.friedman, cdavis5x
Reviewed By: rnk
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D2953
llvm-svn: 202951
Introduce a notion of a 'current representation method' for
pointers-to-members.
When starting out, this is set to 'best case' (representation method is
chosen by examining the class, selecting the smallest representation
that would work given the class definition or lack thereof).
This pragma allows the translation unit to dictate exactly what
representation to use, similar to how the inheritance model keywords
operate.
N.B. PCH support is forthcoming.
Differential Revision: http://llvm-reviews.chandlerc.com/D2723
llvm-svn: 201105
Due to statement expressions supported as GCC extension, it is possible
to put 'break' or 'continue' into a loop/switch statement but outside
its body, for example:
for ( ; ({ if (first) { first = 0; continue; } 0; }); )
This code is rejected by GCC if compiled in C mode but is accepted in C++
code. GCC bug 44715 tracks this discrepancy. Clang used code generation
that differs from GCC in both modes: only statement of the third
expression of 'for' behaves as if it was inside loop body.
This change makes code generation more close to GCC, considering 'break'
or 'continue' statement in condition and increment expressions of a
loop as it was inside the loop body. It also adds error for the cases
when 'break'/'continue' appear outside loop due to this syntax. If
code generation differ from GCC, warning is issued.
Differential Revision: http://llvm-reviews.chandlerc.com/D2518
llvm-svn: 199897
encodes the canonical rules for LLVM's style. I noticed this had drifted
quite a bit when cleaning up LLVM, so wanted to clean up Clang as well.
llvm-svn: 198686
1) Teach ExpectAndConsume() to emit expected and expected-after diagnostics
using the generic diagnostic descriptions added in r197972, eliminating another
set of trivial err_expected_* variations while maintaining existing behaviour.
2) Lift SkipUntil() recovery out of ExpectAndConsume(). The Expect/Consume
family of functions are primitive parser operations that now have the
well-defined property of operating on single tokens. Factoring out recovery
exposes opportunities for more consistent and tailored error recover at the
call sites instead of just relying on a bottled SkipUntil formula.
llvm-svn: 198270
Introduce proper facilities to render token spellings using the diagnostic
formatter.
Replaces most of the hard-coded diagnostic messages related to expected tokens,
which all shared the same semantics but had to be multiply defined due to
variations in token order or quote marks.
The associated parser changes are largely mechanical but they expose
commonality in whole chunks of the parser that can now be factored away.
This commit uses C++11 typed enums along with a speculative legacy fallback
until the transition is complete.
Requires corresponding changes in LLVM r197895.
llvm-svn: 197972
lookup, if parsing failed, we did not restore the lexer state properly, and
eventually crashed. This change ensures that we always consume all the tokens
from the new token stream we started to parse the name from inline asm.
llvm-svn: 196182
module. Use the marker to diagnose cases where we try to transition between
submodules when not at the top level (most likely because a closing brace was
missing at the end of a header file, but is also possible if submodule headers
attempt to do something fundamentally non-modular, like our .def files).
llvm-svn: 195543
the GNU documentation: the attribute only appertains to the label if it is
followed by a semicolon. Based on a patch by Aaron Ballman!
llvm-svn: 194869
It's possible to embed the frontend in applications that haven't initialized
backend targets so we need to handle this condition gracefully.
llvm-svn: 193685
This patch wasn't reviewed, and isn't correctly preserving the behaviors
relied upon by QT. I don't have a direct example of fallout, but it
should go through the standard code review process. For example, it
should never have removed the QT test case that was added when fixing
those users.
llvm-svn: 193174
This is a fix to PR17649, caused by fix in r193073. QT uses 'break' statement
to implement their 'foreach' macro. To enable build of QT, this fix reenables
break but only in 'for' statement specifier and only in the third expression.
llvm-svn: 193170
Due to statement expressions supported as GCC extension, it is possible
to put 'break' or 'continue' into a loop/switch statement but outside its
body, for example:
for ( ; ({ if (first) { first = 0; continue; } 0; }); )
Such usage must be diagnosed as an error, GCC rejects it. To recognize
this and similar patterns the flags BreakScope and ContinueScope are
temporarily turned off while parsing condition expression.
Differential Revision: http://llvm-reviews.chandlerc.com/D1762
llvm-svn: 193073
Move some tests from typo-correction.cpp to typo-correction-pt2.cpp
because they were running afoul of the hard-coded limit of 20 typos
corrected. Some of the tests after it were still working due to the
limit not applying to cached corrections and in cases where a non-NULL
MemberContext is passed in to Sema::CorrectTypo. Most of the moved tests
still passed after being moved, but the test involving "data_struct" had
only been passing because the test had exceeded that limit so a fix for
it is also included (most of the changes to ParseStmt.cpp are shared with
and originated from another typo correction impovement that was split
into a separate commit).
llvm-svn: 191544
We generally don't warn about extensions involving keywords reserved
for the implementation, so we shouldn't warn here either: the
standard doesn't require it, and it doesn't provide useful information
to the user.
llvm-svn: 188840
the actual parser and support arbitrary id-expressions.
We're actually basically set up to do arbitrary expressions here
if we wanted to.
Assembly operands permit things like A::x to be written regardless
of language mode, which forces us to embellish the evaluation
context logic somewhat. The logic here under template instantiation
is incorrect; we need to preserve the fact that an expression was
unevaluated. Of course, template instantiation in general is fishy
here because we have no way of delaying semantic analysis in the
MC parser. It's all just fishy.
I've also fixed the serialization of MS asm statements.
This commit depends on an LLVM commit.
llvm-svn: 180976
picking up cleanups from earlier in the statement. Also fix a
crash-on-invalid where a reference to an invalid decl from an
enclosing scope was causing an expression to fail to build, but
only *after* a cleanup was registered from that statement,
causing an assertion downstream.
The crash-on-valid is rdar://13459289.
llvm-svn: 177692
ActOnFinishFullExpr that some of its checks only apply to discarded-value
expressions. This adds missing checks for unexpanded variadic template
parameter packs to a handful of constructs.
llvm-svn: 172485
uncovered.
This required manually correcting all of the incorrect main-module
headers I could find, and running the new llvm/utils/sort_includes.py
script over the files.
I also manually added quite a few missing headers that were uncovered by
shuffling the order or moving headers up to be main-module-headers.
llvm-svn: 169237
C++11 3.3.3/2 "A parameter name shall not be redeclared in the outermost block
of the function definition nor in the outermost block of any handler associated
with a function-try-block."
It's not totally clear to me whether the "FIXME" case is covered by this, but
Richard Smith thinks it probably should be. It's just a bit more involved to
fix that case.
llvm-svn: 167650
Clang will now honor the FP_CONTRACT pragma and emit LLVM
fmuladd intrinsics for expressions of the form A * B + C (when they occur in a
single statement).
llvm-svn: 164989
but can be dereferenced to form an expression which does have viable begin/end
functions, then typo-correct the range, even if something else goes wrong with
the statement (such as inaccessible begin/end or the wrong type of loop
variable).
In order to ensure we recover correctly and produce any followup diagnostics in
this case, redo semantic analysis on the for-range statement outside of the
diagnostic trap, after issuing the typo-correction.
llvm-svn: 164323
CodeGen option to a LangOpt option. In turn, hoist the guard into the parser
so that we avoid the new (and fairly unstable) Sema/AST/CodeGen logic. This
should restore the behavior of clang to that prior to r158325.
<rdar://problem/12163681>
llvm-svn: 162602
The old error message stating that 'begin' was an undeclared identifier
is replaced with a new message explaining that the error is in the range
expression, along with which of the begin() and end() functions was
problematic if relevant.
Additionally, if the range was a pointer type or defines operator*,
attempt to dereference the range, and offer a FixIt if the modified range
works.
llvm-svn: 162248
nested names as id-expressions, using the annot_primary_expr annotation, where
possible. This removes some redundant lookups, and also allows us to
typo-correct within tentative parsing, and to carry on disambiguating past an
identifier which we can determine will fail lookup as both a type and as a
non-type, allowing us to disambiguate more declarations (and thus offer
improved error recovery for such cases).
This also introduces to the parser the notion of a tentatively-declared name,
which is an identifier which we *might* have seen a declaration for in a
tentative parse (but only if we end up disambiguating the tokens as a
declaration). This is necessary to correctly disambiguate cases where a
variable is used within its own initializer.
llvm-svn: 162159
statement. For example,
if (x)
__asm out dx, ax __asm out dx, ax
results in a single inline asm statement (i.e., both "out dx, ax" statements are
predicated on if(x)).
llvm-svn: 161986
attributes in more places where we didn't and catching a lot more issues.
This implements nearly every aspect of C++11 attribute parsing, except for:
- Attributes are permitted on explicit instantiations inside the declarator
(but not preceding the decl-spec)
- Attributes are permitted on friend declarations of functions.
- Multiple instances of the same attribute in an attribute-list (e.g.
[[noreturn, noreturn]], not [[noreturn]] [[noreturn]] which is conforming)
are allowed.
The first two are marked as expected-FIXME in the test file and the latter
is probably a defect and is currently untested.
Thanks to Richard Smith for providing the lion's share of the testcases.
llvm-svn: 159072
Specifically, improve the handling of whitespace, stop saving tokens that are
in comments and fix the case where we have a comment followed by a closing brace
on the next line.
Unfortunately, there's no easy way of testing this code.
llvm-svn: 158367
This improves the conversion diagnostics (by correctly pointing to the loop
construct for conversions that may've been caused by the contextual conversion
to bool caused by a condition expression) and also causes the NULL conversion
warnings to be correctly suppressed when crossing a macro boundary in such a
context. (previously, since the conversion context location was incorrect, the
suppression could not be performed)
Reported by Nico Weber as feedback to r156826.
llvm-svn: 156901
t.c:3:9: error: expected expression
if (x)) {
^
.. which isn't even true - a statement or expression is fine. After:
t.c:3:9: error: extraneous ')' after condition, expected a statement
if (x)) {
^
This is the second part of PR12595
llvm-svn: 155762
us to improve this diagnostic (telling us to insert another ")":
t.c:2:19: error: expected ';' at end of declaration
int x = 4+(5-12));
^
;
to:
t.c:2:19: error: extraneous ')' before ';'
int x = 4+(5-12));
^
...telling us to remove the ")". This is PR12595. There are more uses of ExpectAndConsumeSemi
that could be switched over, but I don't hit them on a daily basis :)
llvm-svn: 155759
attached. Since we do not support any attributes which appertain to a statement
(yet), testing of this is necessarily quite minimal.
Patch by Alexander Kornienko!
llvm-svn: 154723
* In C++11, '[[' is ill-formed unless it starts an attribute-specifier. Reject
array sizes and array indexes which begin with a lambda-expression. Recover by
parsing the lambda as a lambda.
* In Objective-C++11, either '[' could be the start of a message-send.
Fully disambiguate this case: it turns out that the grammars of message-sends,
lambdas and attributes do not actually overlap. Accept any occurrence of '[['
where either '[' starts a message send, but reject a lambda in an array index
just like in C++11 mode.
Implement a couple of changes to the attribute wording which occurred after our
attributes implementation landed:
* In a function-declaration, the attributes go after the exception specification,
not after the right paren.
* A reference type can have attributes applied.
* An 'identifier' in an attribute can also be a keyword. Support for alternative
tokens (iso646 keywords) in attributes to follow.
And some bug fixes:
* Parse attributes after declarator-ids, even if they are not simple identifiers.
* Do not accept attributes after a parenthesized declarator.
* Accept attributes after an array size in a new-type-id.
* Partially disamiguate 'delete' followed by a lambda. More work is required
here for the case where the lambda-introducer is '[]'.
llvm-svn: 154369
grammar requires a string-literal and not a user-defined-string-literal. The
two constructs are still represented by the same TokenKind, in order to prevent
a combinatorial explosion of different kinds of token. A flag on Token tracks
whether a ud-suffix is present, in order to prevent clients from needing to look
at the token's spelling.
llvm-svn: 152098
(Hopefully, common usage of these pragmas isn't irregular enough to break our current handling. Doug has ideas for a more crazy approach if necessary.)
llvm-svn: 151307
loop and switch statements, by teaching Scope that a function scope never has
a continue/break parent for the purposes of control flow. Remove the hack in
block and lambda expressions which worked around this by pretending that such
expressions were continue/break scopes.
Remove Scope::ControlParent, since it's unused.
In passing, teach default statements to recover properly from a missing ';', and
add a fixit for same to both default and case labels (the latter already
recovered correctly).
llvm-svn: 150776
* if, switch, range-based for: warn if semicolon is on the same line.
* for, while: warn if semicolon is on the same line and either next
statement is compound statement or next statement has more
indentation.
Replacing the semicolon with {} or moving the semicolon to the next
line will always silence the warning.
Tests from SemaCXX/if-empty-body.cpp merged into SemaCXX/warn-empty-body.cpp.
llvm-svn: 150515
statements. As noted in the documentation for the AST node, the
semantics of __if_exists/__if_not_exists are somewhat different from
the way Visual C++ implements them, because our parsed-template
representation can't accommodate VC++ semantics without serious
contortions. Hopefully this implementation is "good enough".
llvm-svn: 142901
Reid Kleckner