The minimizer strips out single-line comments (introduced by `//`). This sequence of characters can also appear in `#include` or `#import` directives where they play the role of path separators. We already avoid stripping this character sequence for `#include` but not for `#import` (which has the same semantics). This patch makes it so `#import <A//A.h>` is not affected by minimization. Previously, we would incorrectly reduce it into `#import <A`.
Reviewed By: arphaman
Differential Revision: https://reviews.llvm.org/D119226
The minimizer tries to squash multi-line macro definitions into single line. For that to work, contents of each line need to be separated by a space. Since we always strip leading whitespace on lines of a macro definition, the code currently tries to preserve exactly one space that appeared before the backslash.
This means the following code:
```
#define FOO(BAR) \
#BAR \
baz
```
gets minimized into:
```
#define FOO(BAR) #BAR baz
```
However, if there are no spaces before the backslash on line 2:
```
#define FOO(BAR) \
#BAR\
baz
```
no space can be preserved, leading to (most likely) malformed macro definition:
```
#define FOO(BAR) #BARbaz
```
This patch makes sure we always put exactly one space at the end of line ending with a backslash.
Reviewed By: arphaman
Differential Revision: https://reviews.llvm.org/D119231
The #pragma directives push_macro/pop_macro and include_alias may influence the #include / import directives encountered by dependency scanning tools like clang-scan-deps.
This patch ensures that those directives are not removed during source code minimization.
Differential Revision: https://reviews.llvm.org/D112088
WG14 adopted N2645 and WG21 EWG has accepted P2334 in principle (still
subject to full EWG vote + CWG review + plenary vote), which add
support for #elifdef as shorthand for #elif defined and #elifndef as
shorthand for #elif !defined. This patch adds support for the new
preprocessor directives.
This patch makes the minimizer more conservative to avoid missing dependency files that are brought in by __has_include
PP expressions that occur in a condition of an #if/#elif that was previously skipped. The __has_include PP expressions
can be used in an #if/#elif either directly, or through macro expansion, so we can't detect them at the time of minimization.
Differential Revision: https://reviews.llvm.org/D70936
The existing string/character literal skipping code in the
dependency directives source minimizer has two issues:
- It doesn't stop the scanning when a newline is reached before the terminating character,
unlike the lexer which considers the token to be done (even if it's invalid) at the end of the line.
- It doesn't support whitespace between '\' and the newline when looking if the '\' is used as a line continuation character.
This commit fixes both issues.
Differential Revision: https://reviews.llvm.org/D68436
llvm-svn: 374127
in the dependency source minimizer
Clang allows continuations that have whitespace between the backslash and the newline.
This patch ensures that the dependency source minimizer can handle the whitespace between
the backslash and the newline when looking for a line continuation.
Differential Revision: https://reviews.llvm.org/D68052
llvm-svn: 373007
In case of certain #define'd macros, there's a space just before line continuation
that the minimized-source lexer was missing to include, resulting in invalid stringize.
Patch by: kousikk (Kousik Kumar)
Differential Revision: https://reviews.llvm.org/D67635
llvm-svn: 372360
This commit adds an optimization to clang-scan-deps and clang's preprocessor that skips excluded preprocessor
blocks by bumping the lexer pointer, and not lexing the tokens until reaching appropriate #else/#endif directive.
The skip positions and lexer offsets are computed when the file is minimized, directly from the minimized tokens.
On an 18-core iMacPro with macOS Catalina Beta I got 10-15% speed-up from this optimization when running clang-scan-deps on
the compilation database for a recent LLVM and Clang (3511 files).
Differential Revision: https://reviews.llvm.org/D67127
llvm-svn: 371656
We should re-emit `#pragma once` to ensure the preprocessor will
still honor it when running on minimized sources.
Differential Revision: https://reviews.llvm.org/D64945
llvm-svn: 366509
single quotes are not digit separators after a valid character literal prefix
The single quote character can act as a c++ digit separator.
However, the minimizer shouldn't treat it as such when it's actually following
a valid character literal prefix, like L, U, u, or u8.
Differential Revision: https://reviews.llvm.org/D64525
llvm-svn: 365700
r362459 introduced DependencyDirectivesSourceMinimizerTest.cpp, which
hits an MSVC bug:
developercommunity.visualstudio.com/content/problem/67300/stringifying-raw-string-literal.html
This only happens when the parameter to a macro is stringified in the
macro. This patch removes the string from the assert so that the
warning no longer happens.
llvm-svn: 363074
that might affect the dependency list for a compilation
This commit introduces a dependency directives source minimizer to clang
that minimizes header and source files to the minimum necessary preprocessor
directives for evaluating includes. It reduces the source down to #define, #include,
The source minimizer works by lexing the input with a custom fast lexer that recognizes
the preprocessor directives it cares about, and emitting those directives in the minimized source.
It ignores source code, comments, and normalizes whitespace. It gives up and fails if seems
any directives that it doesn't recognize as valid (e.g. #define 0).
In addition to the source minimizer this patch adds a
-print-dependency-directives-minimized-source CC1 option that allows you to invoke the minimizer
from clang directly.
Differential Revision: https://reviews.llvm.org/D55463
llvm-svn: 362459
Jan Svoboda