C bindings for libLLVMCore.a and libLLVMBitWriter.a.

- The naming prefix is LLVM.
- All types are represented using opaque references.
- Functions are not named LLVM{Type}{Method}; the names became
  unreadable goop. Instead, they are named LLVM{ImperativeSentence}.
- Where an attribute only appears once in the class hierarchy (e.g.,
  linkage only applies to values; parameter types only apply to
  function types), the class is omitted from identifiers for
  brevity. Tastes like methods.
- Strings are C strings or string/length tuples on a case-by-case
  basis.
- APIs which give the caller ownership of an object are not mapped
  (removeFromParent, certain constructor overloads). This keeps
  keep memory management as simple as possible.

For each library with bindings:

  llvm-c/<LIB>.h       - Declares the bindings.
  lib/<LIB>/<LIB>.cpp  - Implements the bindings.

So just link with the library of your choice and use the C header
instead of the C++ one.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42077 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 94 insertions, 0 deletions

diff --git a/include/llvm/CHelpers.h b/include/llvm/CHelpers.h
new file mode 100644
index 0000000..d00aba3
--- /dev/null
+++ b/include/llvm/CHelpers.h
@@ -0,0 +1,94 @@
+//===-- Support/CHelpers.h - Utilities for writing C bindings -------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+// 
+// These opaque reference<-->pointer conversions are shorter and more tightly
+// typed than writing the casts by hand in C bindings. In assert builds, they
+// will do type checking.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_CHELPERS_H
+#define LLVM_SUPPORT_CHELPERS_H
+
+#include "llvm/Module.h"
+#include "llvm/Type.h"
+#include "llvm/Value.h"
+
+typedef struct LLVMOpaqueModule *LLVMModuleRef;
+typedef struct LLVMOpaqueType *LLVMTypeRef;
+typedef struct LLVMOpaqueValue *LLVMValueRef;
+
+namespace llvm {
+  /// Opaque module conversions
+  /// 
+  inline Module *unwrap(LLVMModuleRef M) {
+    return reinterpret_cast<Module*>(M);
+  }
+  
+  inline LLVMModuleRef wrap(Module *M) {
+    return reinterpret_cast<LLVMModuleRef>(M);
+  }
+  
+  /// Opaque type conversions
+  /// 
+  inline Type *unwrap(LLVMTypeRef Ty) {
+    return reinterpret_cast<Type*>(Ty);
+  }
+  
+  template<typename T>
+  inline T *unwrap(LLVMTypeRef Ty) {
+    return cast<T>(unwrap(Ty));
+  }
+  
+  inline Type **unwrap(LLVMTypeRef* Tys) {
+    return reinterpret_cast<Type**>(Tys);
+  }
+  
+  inline LLVMTypeRef wrap(const Type *Ty) {
+    return reinterpret_cast<LLVMTypeRef>(const_cast<Type*>(Ty));
+  }
+  
+  inline LLVMTypeRef *wrap(const Type **Tys) {
+    return reinterpret_cast<LLVMTypeRef*>(const_cast<Type**>(Tys));
+  }
+  
+  /// Opaque value conversions
+  /// 
+  inline Value *unwrap(LLVMValueRef Val) {
+    return reinterpret_cast<Value*>(Val);
+  }
+  
+  template<typename T>
+  inline T *unwrap(LLVMValueRef Val) {
+    return cast<T>(unwrap(Val));
+  }
+
+  inline Value **unwrap(LLVMValueRef *Vals) {
+    return reinterpret_cast<Value**>(Vals);
+  }
+  
+  template<typename T>
+  inline T **unwrap(LLVMValueRef *Vals, unsigned Length) {
+    #if DEBUG
+    for (LLVMValueRef *I = Vals, E = Vals + Length; I != E; ++I)
+      cast<T>(*I);
+    #endif
+    return reinterpret_cast<T**>(Vals);
+  }
+  
+  inline LLVMValueRef wrap(const Value *Val) {
+    return reinterpret_cast<LLVMValueRef>(const_cast<Value*>(Val));
+  }
+  
+  inline LLVMValueRef *wrap(const Value **Vals) {
+    return reinterpret_cast<LLVMValueRef*>(const_cast<Value**>(Vals));
+  }
+}
+
+#endif