forked from OSchip/llvm-project
8da737a18a
The vec_sld interface provides access to the vsldoi instruction. Unlike most of the vec_* interfaces, we do not attempt to change the generated code for vec_sld based on the endian mode. It is too difficult to correctly infer the desired semantics because of different element types, and the corrected instruction sequence is expensive, involving loading a permute control vector and performing a generalized permute. For GCC, this was implemented as "Don't touch the vec_sld" implementation. When it came time for the LLVM implementation, I did the same thing. However, this was hasty and incorrect. In LLVM's version of altivec.h, vec_sld was previously defined in terms of the vec_perm interface. Because vec_perm semantics are adjusted for little endian, this means that leaving vec_sld untouched causes it to generate something different for LE than for BE. Not good. This patch adjusts the form of vec_perm that is used for vec_sld and vec_vsldoi, effectively undoing the modifications so that the same vsldoi instruction will be generated for both BE and LE. There is an accompanying back-end patch to take care of some small ripple effects caused by these changes. llvm-svn: 242297 |
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| INPUTS | ||
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| include | ||
| lib | ||
| runtime | ||
| test | ||
| tools | ||
| unittests | ||
| utils | ||
| www | ||
| .arcconfig | ||
| .clang-format | ||
| .clang-tidy | ||
| .gitignore | ||
| CMakeLists.txt | ||
| CODE_OWNERS.TXT | ||
| INSTALL.txt | ||
| LICENSE.TXT | ||
| Makefile | ||
| ModuleInfo.txt | ||
| NOTES.txt | ||
| README.txt | ||
README.txt
//===----------------------------------------------------------------------===// // C Language Family Front-end //===----------------------------------------------------------------------===// Welcome to Clang. This is a compiler front-end for the C family of languages (C, C++, Objective-C, and Objective-C++) which is built as part of the LLVM compiler infrastructure project. Unlike many other compiler frontends, Clang is useful for a number of things beyond just compiling code: we intend for Clang to be host to a number of different source-level tools. One example of this is the Clang Static Analyzer. If you're interested in more (including how to build Clang) it is best to read the relevant web sites. Here are some pointers: Information on Clang: http://clang.llvm.org/ Building and using Clang: http://clang.llvm.org/get_started.html Clang Static Analyzer: http://clang-analyzer.llvm.org/ Information on the LLVM project: http://llvm.org/ If you have questions or comments about Clang, a great place to discuss them is on the Clang development mailing list: http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev If you find a bug in Clang, please file it in the LLVM bug tracker: http://llvm.org/bugs/