Syntax:
asm [volatile] goto ( AssemblerTemplate
:
: InputOperands
: Clobbers
: GotoLabels)
https://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html
New llvm IR is "callbr" for inline asm goto instead "call" for inline asm
For:
asm goto("testl %0, %0; jne %l1;" :: "r"(cond)::label_true, loop);
IR:
callbr void asm sideeffect "testl $0, $0; jne ${1:l};", "r,X,X,~{dirflag},~{fpsr},~{flags}"(i32 %0, i8* blockaddress(@foo, %label_true), i8* blockaddress(@foo, %loop)) #1
to label %asm.fallthrough [label %label_true, label %loop], !srcloc !3
asm.fallthrough:
Compiler need to generate:
1> a dummy constarint 'X' for each label.
2> an unique fallthrough label for each asm goto stmt " asm.fallthrough%number".
Diagnostic
1> duplicate asm operand name are used in output, input and label.
2> goto out of scope.
llvm-svn: 362045
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
This is similar to the LLVM change https://reviews.llvm.org/D46290.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46320
llvm-svn: 331834
ARC mode.
Declaring __strong pointer fields in structs was not allowed in
Objective-C ARC until now because that would make the struct non-trivial
to default-initialize, copy/move, and destroy, which is not something C
was designed to do. This patch lifts that restriction.
Special functions for non-trivial C structs are synthesized that are
needed to default-initialize, copy/move, and destroy the structs and
manage the ownership of the objects the __strong pointer fields point
to. Non-trivial structs passed to functions are destructed in the callee
function.
rdar://problem/33599681
Differential Revision: https://reviews.llvm.org/D41228
llvm-svn: 326307
This commit adds a traversal of the AST after Sema of a function that diagnoses
unguarded references to declarations that are partially available (based on
availability attributes). This traversal is only done when we would otherwise
emit -Wpartial-availability.
This commit is part of a feature I proposed here:
http://lists.llvm.org/pipermail/cfe-dev/2016-July/049851.html
Differential revision: https://reviews.llvm.org/D23003
llvm-svn: 278826
(currently theoretical) bug where recursive calls to BuildScopeInformation
would do the wrong thing if the type of the statement is one of the kinds with
special handling, but this is not currently observable because the relevant
recursive calls happen to all be for CompoundStmts. (This becomes visible with
the C++17 'constexpr if' feature, where we get a protected scope for the 'then'
/ 'else' cases of some 'if's, and don't necessarily have a corresponding
compound statement.)
llvm-svn: 273309
This only warns on direct gotos and indirect gotos with a unique label
(`goto *&&label;`). Jumping out ith a true indirect goto is already an error.
This isn't O(1), but goto statements are less common than continue, break, and
return. Also, the GetDeepestCommonScope() call in the same function does the
same amount of work, so this isn't worse than what's there in a complexity
sense, and it should be pretty fast in practice.
This is the last piece that was missing in r231623.
llvm-svn: 231628
Thou shall not jump into SEH blocks. Jumping out of SEH __try and __excepts
is A-ok. Jumping out of __finally blocks is B-ok (msvc doesn't error about it,
but warns that it has undefined behavior).
I've checked that clang's behavior with this patch matches msvc's behavior.
We don't have the warning on jumping out of a __finally yet, see the FIXME
in the test. clang also currently crashes on codegen for a jump out of a
__finally block, see PR22414 comment 7.
I also added a few tests for the interaction of indirect jumps and SEH blocks.
MSVC doesn't support indirect jumps, so there's no way to know if clang behave
the same way as msvc here. clang's behavior with this patch does make sense
to me, but maybe it could be argued that it should be more permissive (see
FIXME in the indirect jump tests -- shout if you have an opinion on this).
llvm-svn: 227982
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
Summary:
This fixes PR20023. In order to implement this scoping rule, we piggy
back on the existing LabelDecl machinery, by creating LabelDecl's that
will carry the "internal" name of the inline assembly label, which we
will rewrite the asm label to.
Reviewers: rnk
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D4589
llvm-svn: 218230
ExtWarn/Warnings. Mostly the name of the warning was changed to match the
semantics, but in the PR20356 cases, the warning was about valid code, so the
diagnostic was changed from ExtWarn to Warning instead.
llvm-svn: 213443
This lets us diagnose and perform more complete semantic analysis when faced
with errors in the function body or declaration.
By recovering here we provide more consistent diagnostics, particularly during
interactive editing.
llvm-svn: 208394
There's been long-standing confusion over the role of these two options. This
commit makes the necessary changes to differentiate them clearly, following up
from r198936.
MicrosoftExt (aka. fms-extensions):
Enable largely unobjectionable Microsoft language extensions to ease
portability. This mode, also supported by gcc, is used for building software
like FreeBSD and Linux kernel extensions that share code with Windows drivers.
MSVCCompat (aka. -fms-compatibility, formerly MicrosoftMode):
Turn on a special mode supporting 'heinous' extensions for drop-in
compatibility with the Microsoft Visual C++ product. Standards-compilant C and
C++ code isn't guaranteed to work in this mode. Implies MicrosoftExt.
Note that full -fms-compatibility mode is currently enabled by default on the
Windows target, which may need tuning to serve as a reasonable default.
See cfe-commits for the full discourse, thread 'r198497 - Move MS predefined
type_info out of InitializePredefinedMacros'
No change in behaviour.
llvm-svn: 199209
declarations that might lifetime-extend multiple temporaries. In passing, fix a
crasher (PR18217) if an initializer was dependent and exactly the wrong shape,
and remove a bogus function (Expr::findMaterializedTemporary) now its last use
is gone.
llvm-svn: 197103
Changed getLocStart() and getLocEnd() to be required for Stmts, and make
getSourceRange() optional. The default implementation for getSourceRange()
is build the range by calling getLocStart() and getLocEnd().
llvm-svn: 171067
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
into the enclosing scope; this is a more accurate model but is
(I believe) unnecessary in my test case due to other flaws.
However, one of those flaws is now intentional: blocks which
appear in return statements can be trivially observed to not
extend in lifetime past the return, and so we can allow a jump
past them. Do the necessary magic in IR-generation to make
this work.
llvm-svn: 164589
but trivially constructible and destructible variables in C++11 mode. Also
incidentally improve the precision of the wording for jump diagnostics in C++98
mode.
llvm-svn: 142619
Jennifer Yu