Commit Graph

6 Commits

Author SHA1 Message Date
Alex Lorenz ca6e60971e [clang-scan-deps] add skip excluded conditional preprocessor block preprocessing optimization
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
2019-09-11 20:40:31 +00:00
Michael J. Spencer 1861f4ea25 [clang-scan-deps] Add minimizer support for C++20 modules.
This only adds support to the minimizer, it doesn't actually capture the dependencies yet.

llvm-svn: 368381
2019-08-09 02:01:10 +00:00
Alex Lorenz 4cd905bdc1 [clang-scan-deps] Dependency directives source minimizer: handle #pragma once
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
2019-07-18 22:33:14 +00:00
Alex Lorenz 9a6c17b5b8 [clang-scan-deps] Dependency directives source minimizer:
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
2019-07-10 22:00:59 +00:00
Erich Keane d65ef6735a Fix for r42230, MSVC test failure in DependencyDirectivesSourceMinimizerTest.cpp
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
2019-06-11 14:58:26 +00:00
Alex Lorenz 6e2d36b60b Add clang source minimizer that reduces source to directives
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
2019-06-03 22:59:17 +00:00