1//===---- llvm/TypeBuilder.h - Builder for LLVM types -----------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines the TypeBuilder class, which is used as a convenient way to
11// create LLVM types with a consistent and simplified interface.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_IR_TYPEBUILDER_H
16#define LLVM_IR_TYPEBUILDER_H
17
18#include "llvm/IR/DerivedTypes.h"
19#include "llvm/IR/LLVMContext.h"
20#include <climits>
21
22namespace llvm {
23
24/// TypeBuilder - This provides a uniform API for looking up types
25/// known at compile time.  To support cross-compilation, we define a
26/// series of tag types in the llvm::types namespace, like i<N>,
27/// ieee_float, ppc_fp128, etc.  TypeBuilder<T, false> allows T to be
28/// any of these, a native C type (whose size may depend on the host
29/// compiler), or a pointer, function, or struct type built out of
30/// these.  TypeBuilder<T, true> removes native C types from this set
31/// to guarantee that its result is suitable for cross-compilation.
32/// We define the primitive types, pointer types, and functions up to
33/// 5 arguments here, but to use this class with your own types,
34/// you'll need to specialize it.  For example, say you want to call a
35/// function defined externally as:
36///
37///   struct MyType {
38///     int32 a;
39///     int32 *b;
40///     void *array[1];  // Intended as a flexible array.
41///   };
42///   int8 AFunction(struct MyType *value);
43///
44/// You'll want to use
45///   Function::Create(TypeBuilder<types::i<8>(MyType*), true>::get(), ...)
46/// to declare the function, but when you first try this, your compiler will
47/// complain that TypeBuilder<MyType, true>::get() doesn't exist. To fix this,
48/// write:
49///
50///   namespace llvm {
51///   template<bool xcompile> class TypeBuilder<MyType, xcompile> {
52///   public:
53///     static StructType *get(LLVMContext &Context) {
54///       // If you cache this result, be sure to cache it separately
55///       // for each LLVMContext.
56///       return StructType::get(
57///         TypeBuilder<types::i<32>, xcompile>::get(Context),
58///         TypeBuilder<types::i<32>*, xcompile>::get(Context),
59///         TypeBuilder<types::i<8>*[], xcompile>::get(Context),
60///         NULL);
61///     }
62///
63///     // You may find this a convenient place to put some constants
64///     // to help with getelementptr.  They don't have any effect on
65///     // the operation of TypeBuilder.
66///     enum Fields {
67///       FIELD_A,
68///       FIELD_B,
69///       FIELD_ARRAY
70///     };
71///   }
72///   }  // namespace llvm
73///
74/// TypeBuilder cannot handle recursive types or types you only know at runtime.
75/// If you try to give it a recursive type, it will deadlock, infinitely
76/// recurse, or do something similarly undesirable.
77template<typename T, bool cross_compilable> class TypeBuilder {};
78
79// Types for use with cross-compilable TypeBuilders.  These correspond
80// exactly with an LLVM-native type.
81namespace types {
82/// i<N> corresponds to the LLVM IntegerType with N bits.
83template<uint32_t num_bits> class i {};
84
85// The following classes represent the LLVM floating types.
86class ieee_float {};
87class ieee_double {};
88class x86_fp80 {};
89class fp128 {};
90class ppc_fp128 {};
91// X86 MMX.
92class x86_mmx {};
93}  // namespace types
94
95// LLVM doesn't have const or volatile types.
96template<typename T, bool cross> class TypeBuilder<const T, cross>
97  : public TypeBuilder<T, cross> {};
98template<typename T, bool cross> class TypeBuilder<volatile T, cross>
99  : public TypeBuilder<T, cross> {};
100template<typename T, bool cross> class TypeBuilder<const volatile T, cross>
101  : public TypeBuilder<T, cross> {};
102
103// Pointers
104template<typename T, bool cross> class TypeBuilder<T*, cross> {
105public:
106  static PointerType *get(LLVMContext &Context) {
107    return PointerType::getUnqual(TypeBuilder<T,cross>::get(Context));
108  }
109};
110
111/// There is no support for references
112template<typename T, bool cross> class TypeBuilder<T&, cross> {};
113
114// Arrays
115template<typename T, size_t N, bool cross> class TypeBuilder<T[N], cross> {
116public:
117  static ArrayType *get(LLVMContext &Context) {
118    return ArrayType::get(TypeBuilder<T, cross>::get(Context), N);
119  }
120};
121/// LLVM uses an array of length 0 to represent an unknown-length array.
122template<typename T, bool cross> class TypeBuilder<T[], cross> {
123public:
124  static ArrayType *get(LLVMContext &Context) {
125    return ArrayType::get(TypeBuilder<T, cross>::get(Context), 0);
126  }
127};
128
129// Define the C integral types only for TypeBuilder<T, false>.
130//
131// C integral types do not have a defined size. It would be nice to use the
132// stdint.h-defined typedefs that do have defined sizes, but we'd run into the
133// following problem:
134//
135// On an ILP32 machine, stdint.h might define:
136//
137//   typedef int int32_t;
138//   typedef long long int64_t;
139//   typedef long size_t;
140//
141// If we defined TypeBuilder<int32_t> and TypeBuilder<int64_t>, then any use of
142// TypeBuilder<size_t> would fail.  We couldn't define TypeBuilder<size_t> in
143// addition to the defined-size types because we'd get duplicate definitions on
144// platforms where stdint.h instead defines:
145//
146//   typedef int int32_t;
147//   typedef long long int64_t;
148//   typedef int size_t;
149//
150// So we define all the primitive C types and nothing else.
151#define DEFINE_INTEGRAL_TYPEBUILDER(T) \
152template<> class TypeBuilder<T, false> { \
153public: \
154  static IntegerType *get(LLVMContext &Context) { \
155    return IntegerType::get(Context, sizeof(T) * CHAR_BIT); \
156  } \
157}; \
158template<> class TypeBuilder<T, true> { \
159  /* We provide a definition here so users don't accidentally */ \
160  /* define these types to work. */ \
161}
162DEFINE_INTEGRAL_TYPEBUILDER(char);
163DEFINE_INTEGRAL_TYPEBUILDER(signed char);
164DEFINE_INTEGRAL_TYPEBUILDER(unsigned char);
165DEFINE_INTEGRAL_TYPEBUILDER(short);
166DEFINE_INTEGRAL_TYPEBUILDER(unsigned short);
167DEFINE_INTEGRAL_TYPEBUILDER(int);
168DEFINE_INTEGRAL_TYPEBUILDER(unsigned int);
169DEFINE_INTEGRAL_TYPEBUILDER(long);
170DEFINE_INTEGRAL_TYPEBUILDER(unsigned long);
171#ifdef _MSC_VER
172DEFINE_INTEGRAL_TYPEBUILDER(__int64);
173DEFINE_INTEGRAL_TYPEBUILDER(unsigned __int64);
174#else /* _MSC_VER */
175DEFINE_INTEGRAL_TYPEBUILDER(long long);
176DEFINE_INTEGRAL_TYPEBUILDER(unsigned long long);
177#endif /* _MSC_VER */
178#undef DEFINE_INTEGRAL_TYPEBUILDER
179
180template<uint32_t num_bits, bool cross>
181class TypeBuilder<types::i<num_bits>, cross> {
182public:
183  static IntegerType *get(LLVMContext &C) {
184    return IntegerType::get(C, num_bits);
185  }
186};
187
188template<> class TypeBuilder<float, false> {
189public:
190  static Type *get(LLVMContext& C) {
191    return Type::getFloatTy(C);
192  }
193};
194template<> class TypeBuilder<float, true> {};
195
196template<> class TypeBuilder<double, false> {
197public:
198  static Type *get(LLVMContext& C) {
199    return Type::getDoubleTy(C);
200  }
201};
202template<> class TypeBuilder<double, true> {};
203
204template<bool cross> class TypeBuilder<types::ieee_float, cross> {
205public:
206  static Type *get(LLVMContext& C) { return Type::getFloatTy(C); }
207};
208template<bool cross> class TypeBuilder<types::ieee_double, cross> {
209public:
210  static Type *get(LLVMContext& C) { return Type::getDoubleTy(C); }
211};
212template<bool cross> class TypeBuilder<types::x86_fp80, cross> {
213public:
214  static Type *get(LLVMContext& C) { return Type::getX86_FP80Ty(C); }
215};
216template<bool cross> class TypeBuilder<types::fp128, cross> {
217public:
218  static Type *get(LLVMContext& C) { return Type::getFP128Ty(C); }
219};
220template<bool cross> class TypeBuilder<types::ppc_fp128, cross> {
221public:
222  static Type *get(LLVMContext& C) { return Type::getPPC_FP128Ty(C); }
223};
224template<bool cross> class TypeBuilder<types::x86_mmx, cross> {
225public:
226  static Type *get(LLVMContext& C) { return Type::getX86_MMXTy(C); }
227};
228
229template<bool cross> class TypeBuilder<void, cross> {
230public:
231  static Type *get(LLVMContext &C) {
232    return Type::getVoidTy(C);
233  }
234};
235
236/// void* is disallowed in LLVM types, but it occurs often enough in C code that
237/// we special case it.
238template<> class TypeBuilder<void*, false>
239  : public TypeBuilder<types::i<8>*, false> {};
240template<> class TypeBuilder<const void*, false>
241  : public TypeBuilder<types::i<8>*, false> {};
242template<> class TypeBuilder<volatile void*, false>
243  : public TypeBuilder<types::i<8>*, false> {};
244template<> class TypeBuilder<const volatile void*, false>
245  : public TypeBuilder<types::i<8>*, false> {};
246
247template<typename R, bool cross> class TypeBuilder<R(), cross> {
248public:
249  static FunctionType *get(LLVMContext &Context) {
250    return FunctionType::get(TypeBuilder<R, cross>::get(Context), false);
251  }
252};
253template<typename R, typename A1, bool cross> class TypeBuilder<R(A1), cross> {
254public:
255  static FunctionType *get(LLVMContext &Context) {
256    Type *params[] = {
257      TypeBuilder<A1, cross>::get(Context),
258    };
259    return FunctionType::get(TypeBuilder<R, cross>::get(Context),
260                             params, false);
261  }
262};
263template<typename R, typename A1, typename A2, bool cross>
264class TypeBuilder<R(A1, A2), cross> {
265public:
266  static FunctionType *get(LLVMContext &Context) {
267    Type *params[] = {
268      TypeBuilder<A1, cross>::get(Context),
269      TypeBuilder<A2, cross>::get(Context),
270    };
271    return FunctionType::get(TypeBuilder<R, cross>::get(Context),
272                             params, false);
273  }
274};
275template<typename R, typename A1, typename A2, typename A3, bool cross>
276class TypeBuilder<R(A1, A2, A3), cross> {
277public:
278  static FunctionType *get(LLVMContext &Context) {
279    Type *params[] = {
280      TypeBuilder<A1, cross>::get(Context),
281      TypeBuilder<A2, cross>::get(Context),
282      TypeBuilder<A3, cross>::get(Context),
283    };
284    return FunctionType::get(TypeBuilder<R, cross>::get(Context),
285                             params, false);
286  }
287};
288
289template<typename R, typename A1, typename A2, typename A3, typename A4,
290         bool cross>
291class TypeBuilder<R(A1, A2, A3, A4), cross> {
292public:
293  static FunctionType *get(LLVMContext &Context) {
294    Type *params[] = {
295      TypeBuilder<A1, cross>::get(Context),
296      TypeBuilder<A2, cross>::get(Context),
297      TypeBuilder<A3, cross>::get(Context),
298      TypeBuilder<A4, cross>::get(Context),
299    };
300    return FunctionType::get(TypeBuilder<R, cross>::get(Context),
301                             params, false);
302  }
303};
304
305template<typename R, typename A1, typename A2, typename A3, typename A4,
306         typename A5, bool cross>
307class TypeBuilder<R(A1, A2, A3, A4, A5), cross> {
308public:
309  static FunctionType *get(LLVMContext &Context) {
310    Type *params[] = {
311      TypeBuilder<A1, cross>::get(Context),
312      TypeBuilder<A2, cross>::get(Context),
313      TypeBuilder<A3, cross>::get(Context),
314      TypeBuilder<A4, cross>::get(Context),
315      TypeBuilder<A5, cross>::get(Context),
316    };
317    return FunctionType::get(TypeBuilder<R, cross>::get(Context),
318                             params, false);
319  }
320};
321
322template<typename R, bool cross> class TypeBuilder<R(...), cross> {
323public:
324  static FunctionType *get(LLVMContext &Context) {
325    return FunctionType::get(TypeBuilder<R, cross>::get(Context), true);
326  }
327};
328template<typename R, typename A1, bool cross>
329class TypeBuilder<R(A1, ...), cross> {
330public:
331  static FunctionType *get(LLVMContext &Context) {
332    Type *params[] = {
333      TypeBuilder<A1, cross>::get(Context),
334    };
335    return FunctionType::get(TypeBuilder<R, cross>::get(Context), params, true);
336  }
337};
338template<typename R, typename A1, typename A2, bool cross>
339class TypeBuilder<R(A1, A2, ...), cross> {
340public:
341  static FunctionType *get(LLVMContext &Context) {
342    Type *params[] = {
343      TypeBuilder<A1, cross>::get(Context),
344      TypeBuilder<A2, cross>::get(Context),
345    };
346    return FunctionType::get(TypeBuilder<R, cross>::get(Context),
347                                   params, true);
348  }
349};
350template<typename R, typename A1, typename A2, typename A3, bool cross>
351class TypeBuilder<R(A1, A2, A3, ...), cross> {
352public:
353  static FunctionType *get(LLVMContext &Context) {
354    Type *params[] = {
355      TypeBuilder<A1, cross>::get(Context),
356      TypeBuilder<A2, cross>::get(Context),
357      TypeBuilder<A3, cross>::get(Context),
358    };
359    return FunctionType::get(TypeBuilder<R, cross>::get(Context),
360                                   params, true);
361  }
362};
363
364template<typename R, typename A1, typename A2, typename A3, typename A4,
365         bool cross>
366class TypeBuilder<R(A1, A2, A3, A4, ...), cross> {
367public:
368  static FunctionType *get(LLVMContext &Context) {
369    Type *params[] = {
370      TypeBuilder<A1, cross>::get(Context),
371      TypeBuilder<A2, cross>::get(Context),
372      TypeBuilder<A3, cross>::get(Context),
373      TypeBuilder<A4, cross>::get(Context),
374    };
375    return FunctionType::get(TypeBuilder<R, cross>::get(Context),
376                             params, true);
377  }
378};
379
380template<typename R, typename A1, typename A2, typename A3, typename A4,
381         typename A5, bool cross>
382class TypeBuilder<R(A1, A2, A3, A4, A5, ...), cross> {
383public:
384  static FunctionType *get(LLVMContext &Context) {
385    Type *params[] = {
386      TypeBuilder<A1, cross>::get(Context),
387      TypeBuilder<A2, cross>::get(Context),
388      TypeBuilder<A3, cross>::get(Context),
389      TypeBuilder<A4, cross>::get(Context),
390      TypeBuilder<A5, cross>::get(Context),
391    };
392    return FunctionType::get(TypeBuilder<R, cross>::get(Context),
393                                   params, true);
394  }
395};
396
397}  // namespace llvm
398
399#endif
400