simd/arm/jdsample-neon.c

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Author Commit Date CI Message
DRC 4e151a4a 2025-08-26T21:11:07 Remove vestigial filenames from SIMD code headers These were a relic of libjpeg/SIMD, which attempted to follow the conventions of the libjpeg source code, but they are no longer relevant (or even accurate in some cases.)
DRC ea4ee229 2024-12-11T16:51:39 Neon: Disable some strict compiler warnings We use a standard set of strict compiler warnings with Clang and GCC to continuously test and maintain C89 conformance in the libjpeg API code. However, SIMD extensions need not comply with that. The Neon code specifically uses some C99isms, so disable -Wdeclaration-after-statement, -Wc99-extensions, and -Wpedantic in the scope of that code. Also modify the Neon feature tests so that they will succeed if any of the aforementioned compiler warnings are enabled.
DRC e69dd40c 2024-01-23T13:26:41 Reorganize source to make things easier to find - Move all libjpeg documentation, except for README.ijg, into the doc/ subdirectory. - Move the TurboJPEG C API documentation from doc/html/ into doc/turbojpeg/. - Move all C source code and headers into a src/ subdirectory. - Move turbojpeg-jni.c into the java/ subdirectory. Referring to #226, there is no ideal solution to this problem. A semantically ideal solution would have involved placing all source code, including the SIMD and Java source code, under src/ (or perhaps placing C library source code under lib/ and C test program source code under test/), all header files under include/, and all documentation under doc/. However: - To me it makes more sense to have separate top-level directories for each language, since the SIMD extensions and the Java API are technically optional features. src/ now contains only the code that is relevant to the core C API libraries and associated programs. - I didn't want to bury the java/ and simd/ directories or add a level of depth to them, since both directories already contain source code that is 3-4 levels deep. - I would prefer not to separate the header files from the C source code, because: 1. It would be disruptive. libjpeg and libjpeg-turbo have historically placed C source code and headers in the same directory, and people who are familiar with both projects (self included) are used to looking for the headers in the same directory as the C source code. 2. In terms of how the headers are used internally in libjpeg-turbo, the distinction between public and private headers is a bit fuzzy. - It didn't make sense to separate the test source code from the library source code, since there is not a clear distinction in some cases. (For instance, the IJG image I/O functions are used by cjpeg and djpeg as well as by the TurboJPEG API.) This solution is minimally disruptive, since it keeps all C source code and headers together and keeps java/ and simd/ as top-level directories. It is a bit awkward, because java/ and simd/ technically contain source code, even though they are not under src/. However, other solutions would have been more awkward for different reasons. Closes #226
Jonathan Wright 4574f01f 2018-06-28T16:17:36 Neon: Intrinsics impl. of h2v1 & h2v2 plain upsamp There was no previous GAS implementation. NOTE: This doesn't produce much of a speedup when using -O3, because -O3 already enables Neon autovectorization, which works well for the scalar C implementation of plain upsampling. However, the Neon SIMD implementation will benefit other optimization levels.
Jonathan Wright 2acfb93c 2019-05-08T15:43:26 Neon: Intrinsics impl. of h1v2 fancy upsamling There was no previous GAS implementation.
Jonathan Wright 97530777 2018-06-15T11:13:52 Neon: Intrinsics impl. of h2v1 & h2v2 fancy upsamp The previous AArch32 GAS implementation of h2v1 fancy upsampling has been removed, since the intrinsics implementation provides the same or better performance. There was no previous GAS implementation of h2v2 fancy upsampling, and there was no previous AArch64 GAS implementation of h2v1 fancy upsampling.