thorough tests.
Original commit message:
[modules] Fix macro hiding bug exposed if:
* A submodule of module A is imported into module B
* Another submodule of module A that is not imported into B exports a macro
* Some submodule of module B also exports a definition of the macro, and
happens to be the first submodule of B that imports module A.
In this case, we would incorrectly determine that A's macro redefines B's
macro, and so we don't need to re-export B's macro at all.
This happens with the 'assert' macro in an LLVM self-host. =(
llvm-svn: 213416
it, importers of B should not see the macro. This is complicated by the fact
that A's macro could also be visible through a different path. The rules (as
hashed out on cfe-commits) are included as a documentation update in this
change.
With this, the number of regressions in libc++'s testsuite when modules are
enabled drops from 47 to 7. Those remaining 7 are also macro-related, and are
due to remaining bugs in this change (in particular, the handling of submodules
is imperfect).
llvm-svn: 202560
Syntactically means the function macro parameter names do not need to use the same
identifiers in order for the definitions to be considered identical.
Syntactic equivalence is a microsoft extension for macro redefinitions and we'll also
use this kind of comparison to check for ambiguous macros coming from modules.
rdar://13562254
llvm-svn: 178671
For each macro directive (define, undefine, visibility) have a separate object that gets chained
to the macro directive history. This has several benefits:
-No need to mutate a MacroDirective when there is a undefine/visibility directive. Stuff like
PPMutationListener become unnecessary.
-No need to keep extra source locations for the undef/visibility locations for the define directive object
(which is the majority of the directives)
-Much easier to hide/unhide a section in the macro directive history.
-Easier to track the effects of the directives across different submodules.
llvm-svn: 178037
* Clarify what MacroInfo::isBuiltinMacro means, as it really means something
more like "isMagicalMacro" or "requiresProcessingBeforeExpansion" -- the
macros defined in "<built-in>" are not considered built-in by this function;
* Escape __LINE__ as \__LINE__ in Doxygen comments so that the underscores
don't get replaced by *bold* output;
* Turn comments in MacroInfo.cpp into non-Doxygen comments, so that they
don't result in duplicated/badly formatted Doxygen output;
* Clean up a bunch of \brief formatting, and add a \file comment for
MacroInfo.h.
llvm-svn: 177581
for the data specific to a macro definition (e.g. what the tokens are), and
MacroDirective class which encapsulates the changes to the "macro namespace"
(e.g. the location where the macro name became active, the location where it was undefined, etc.)
(A MacroDirective always points to a MacroInfo object.)
Usually a macro definition (MacroInfo) is where a macro name becomes active (MacroDirective) but
splitting the concepts allows us to better model the effect of modules to the macro namespace
(also as a bonus it allows better modeling of push_macro/pop_macro #pragmas).
Modules can have their own macro history, separate from the local (current translation unit)
macro history; MacroDirectives will be used to model the macro history (changes to macro namespace).
For example, if "@import A;" imports macro FOO, there will be a new local MacroDirective created
to indicate that "FOO" became active at the import location. Module "A" itself will contain another
MacroDirective in its macro history (at the point of the definition of FOO) and both MacroDirectives
will point to the same MacroInfo object.
Introducing the separation of macro concepts is the first part towards better modeling of module macros.
llvm-svn: 175585
the related comma pasting extension.
In certain cases, we used to get two diagnostics for what is essentially one
extension. This change suppresses the first diagnostic in certain cases
where we know we're going to print the second diagnostic. The
diagnostic is redundant, and it can't be suppressed in the definition
of the macro because it points at the use of the macro, so we want to
avoid printing it if possible.
The implementation works by detecting constructs which look like comma
pasting at the time of the definition of the macro; this information
is then used when the macro is used. (We can't actually detect
whether we're using the comma pasting extension until the macro is
actually used, but we can detecting constructs which will be comma
pasting if the varargs argument is elided.)
<rdar://problem/12292192>
llvm-svn: 167907
macro history.
When deserializing macro history, we arrange history such that the
macros that have definitions (that haven't been #undef'd) and are
visible come at the beginning of the list, which is what the
preprocessor and other clients of Preprocessor::getMacroInfo()
expect. If additional macro definitions become visible later, they'll
be moved toward the front of the list. Note that it's possible to have
ambiguities, but we don't diagnose them yet.
There is a partially-implemented design decision here that, if a
particular identifier has been defined or #undef'd within the
translation unit, that definition (or #undef) hides any macro
definitions that come from imported modules. There's still a little
work to do to ensure that the right #undef'ing happens.
Additionally, we'll need to scope the update records for #undefs, so
they only kick in when the submodule containing that update record
becomes visible.
llvm-svn: 165682
Summary:
When issuing a diagnostic message for the -Wimplicit-fallthrough diagnostics, always try to find the latest macro, defined at the point of fallthrough, which is immediately expanded to "[[clang::fallthrough]]", and use it's name instead of the actual sequence.
Known issues:
* uses PP.getSpelling() to compare macro definition with a string (anyone can suggest a convenient way to fill a token array, or maybe lex it in runtime?);
* this can be generalized and used in other similar cases, any ideas where it should reside then?
Reviewers: doug.gregor, rsmith
Reviewed By: rsmith
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D50
llvm-svn: 164858
Summary:
Summary: Keep history of macro definitions and #undefs with corresponding source locations, so that we can later find out all macros active in a specified source location. We don't save the history in PCH (no need currently). Memory overhead is about sizeof(void*)*3*<number of macro definitions and #undefs>+<in-memory size of all #undef'd macros>
I've run a test on a file composed of 109 .h files from boost 1.49 on x86-64 linux.
Stats before this patch:
*** Preprocessor Stats:
73222 directives found:
19171 #define.
4345 #undef.
#include/#include_next/#import:
5233 source files entered.
27 max include stack depth
19210 #if/#ifndef/#ifdef.
2384 #else/#elif.
6891 #endif.
408 #pragma.
14466 #if/#ifndef#ifdef regions skipped
80023/451669/1270 obj/fn/builtin macros expanded, 85724 on the fast path.
127145 token paste (##) operations performed, 11008 on the fast path.
Preprocessor Memory: 5874615B total
BumpPtr: 4399104
Macro Expanded Tokens: 417768
Predefines Buffer: 8135
Macros: 1048576
#pragma push_macro Info: 0
Poison Reasons: 1024
Comment Handlers: 8
Stats with this patch:
...
Preprocessor Memory: 7541687B total
BumpPtr: 6066176
Macro Expanded Tokens: 417768
Predefines Buffer: 8135
Macros: 1048576
#pragma push_macro Info: 0
Poison Reasons: 1024
Comment Handlers: 8
In my test increase in memory usage is about 1.7Mb, which is ~28% of initial preprocessor's memory usage and about 0.8% of clang's total VMM allocation.
As for CPU overhead, it should only be noticeable when iterating over all macros, and should mostly consist of couple extra dereferences and one comparison per macro + skipping of #undef'd macros. It's less trivial to measure, though, as the preprocessor consumes a very small fraction of compilation time.
Reviewers: doug.gregor, klimek, rsmith, djasper
Reviewed By: doug.gregor
CC: cfe-commits, chandlerc
Differential Revision: http://llvm-reviews.chandlerc.com/D28
llvm-svn: 162810
include guards don't show up as macro definitions in every translation
unit that imports a module. Macro definitions can, however, be
exported with the intentionally-ugly #__export_macro__
directive. Implement this feature by not even bothering to serialize
non-exported macros to a module, because clients of that module need
not (should not) know that these macros even exist.
llvm-svn: 138943
When a macro instantiation occurs, reserve a SLocEntry chunk with length the
full length of the macro definition source. Set the spelling location of this chunk
to point to the start of the macro definition and any tokens that are lexed directly
from the macro definition will get a location from this chunk with the appropriate offset.
For any tokens that come from argument expansion, '##' paste operator, etc. have their
instantiation location point at the appropriate place in the instantiated macro definition
(the argument identifier and the '##' token respectively).
This improves macro instantiation diagnostics:
Before:
t.c:5:9: error: invalid operands to binary expression ('struct S' and 'int')
int y = M(/);
^~~~
t.c:5:11: note: instantiated from:
int y = M(/);
^
After:
t.c:5:9: error: invalid operands to binary expression ('struct S' and 'int')
int y = M(/);
^~~~
t.c:3:20: note: instantiated from:
\#define M(op) (foo op 3);
~~~ ^ ~
t.c:5:11: note: instantiated from:
int y = M(/);
^
The memory savings for a candidate boost library that abuses the preprocessor are:
- 32% less SLocEntries (37M -> 25M)
- 30% reduction in PCH file size (900M -> 635M)
- 50% reduction in memory usage for the SLocEntry table (1.6G -> 800M)
llvm-svn: 134587
Diagnostic pragmas are broken because we don't keep track of the diagnostic state changes and we only check the current/latest state.
Problems manifest if a diagnostic is emitted for a source line that has different diagnostic state than the current state; this can affect
a lot of places, like C++ inline methods, template instantiations, the lexer, etc.
Fix the issue by having the Diagnostic object keep track of the source location of the pragmas so that it is able to know what is the diagnostic state at any given source location.
Fixes rdar://8365684.
llvm-svn: 121873
lib dir and move all the libraries into it. This follows the main
llvm tree, and allows the libraries to be built in parallel. The
top level now enforces that all the libs are built before Driver,
but we don't care what order the libs are built in. This speeds
up parallel builds, particularly incremental ones.
llvm-svn: 48402
Richard Smith