f8bdbed5b3
Enable ClangIR generation for very simple functions. The functions have to return `void` or an integral type, contain only compound statements or `return` statements, and `return` statement expressions can only be integral literals of the correct type. The functions can have parameters, but those are currently ignored because there is no way to access them. This change intentionally focuses on breadth (introducing scopes, statements, and expressions) rather than depth, because it enables people to work on upstreaming in parallel without interference. The new ClangIR ops in this change are `ReturnOp`, `YieldOp`, `ScopeOp`, and `TrapOp`. These operations are complete (except for the `ParentOneOf` property) and shouldn't require further upstreaming changes. Significant additions were made to `FuncOp`, adding a type and a region, but that operation is still far from complete. The classes `ScalarExprEmitter` and `CIRGenFunction`, along with the `emit*` functions in `CIRGenFunction` that generate ClangIR for statements, are new in this change. All of these are very incomplete and will be filled out in later upstreaming patches. Existing test `hello.c` is removed and replaced by the new test `func-simple.cpp`. This tests all forms of functions that are currently supported.
C language Family Front-end
Welcome to Clang.
This is a compiler front-end for the C family of languages (C, 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 websites. Here are some pointers:
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Information on Clang: http://clang.llvm.org/
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Building and using Clang: http://clang.llvm.org/get_started.html
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Clang Static Analyzer: http://clang-analyzer.llvm.org/
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Information on the LLVM project: http://llvm.org/
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If you have questions or comments about Clang, a great place to discuss them is on the Clang forums:
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If you find a bug in Clang, please file it in the LLVM bug tracker: