forked from OSchip/llvm-project
3efe00206f
As documented here: https://software.intel.com/en-us/node/682969 and https://software.intel.com/en-us/node/523346. cpu_dispatch multiversioning is an ICC feature that provides for function multiversioning. This feature is implemented with two attributes: First, cpu_specific, which specifies the individual function versions. Second, cpu_dispatch, which specifies the location of the resolver function and the list of resolvable functions. This is valuable since it provides a mechanism where the resolver's TU can be specified in one location, and the individual implementions each in their own translation units. The goal of this patch is to be source-compatible with ICC, so this implementation diverges from the ICC implementation in a few ways: 1- Linux x86/64 only: This implementation uses ifuncs in order to properly dispatch functions. This is is a valuable performance benefit over the ICC implementation. A future patch will be provided to enable this feature on Windows, but it will obviously more closely fit ICC's implementation. 2- CPU Identification functions: ICC uses a set of custom functions to identify the feature list of the host processor. This patch uses the cpu_supports functionality in order to better align with 'target' multiversioning. 1- cpu_dispatch function def/decl: ICC's cpu_dispatch requires that the function marked cpu_dispatch be an empty definition. This patch supports that as well, however declarations are also permitted, since the linker will solve the issue of multiple emissions. Differential Revision: https://reviews.llvm.org/D47474 llvm-svn: 337552 |
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| .. | ||
| CMakeLists.txt | ||
| ClangASTNodesEmitter.cpp | ||
| ClangAttrEmitter.cpp | ||
| ClangCommentCommandInfoEmitter.cpp | ||
| ClangCommentHTMLNamedCharacterReferenceEmitter.cpp | ||
| ClangCommentHTMLTagsEmitter.cpp | ||
| ClangDataCollectorsEmitter.cpp | ||
| ClangDiagnosticsEmitter.cpp | ||
| ClangOptionDocEmitter.cpp | ||
| ClangSACheckersEmitter.cpp | ||
| NeonEmitter.cpp | ||
| TableGen.cpp | ||
| TableGenBackends.h | ||