Casting.h revision 3a3134ab12f3aa65f9791f702a73f6d0b2af423f
1551ccae044b0ff658fe629dd67edd5ffe75d10e8Reid Spencer//===-- llvm/Support/Casting.h - Allow flexible, checked, casts -*- C++ -*-===// 263b3afa98460ce38a1c48d3c44ef6edfdaf37b77Misha Brukman// 3b2109ce97881269a610fa4afbcbca350e975174dJohn Criswell// The LLVM Compiler Infrastructure 4b2109ce97881269a610fa4afbcbca350e975174dJohn Criswell// 57ed47a13356daed2a34cd2209a31f92552e3bdd8Chris Lattner// This file is distributed under the University of Illinois Open Source 67ed47a13356daed2a34cd2209a31f92552e3bdd8Chris Lattner// License. See LICENSE.TXT for details. 763b3afa98460ce38a1c48d3c44ef6edfdaf37b77Misha Brukman// 8b2109ce97881269a610fa4afbcbca350e975174dJohn Criswell//===----------------------------------------------------------------------===// 9589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// 10589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// This file defines the isa<X>(), cast<X>(), dyn_cast<X>(), cast_or_null<X>(), 11589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// and dyn_cast_or_null<X>() templates. 12589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// 13589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner//===----------------------------------------------------------------------===// 14589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner 15551ccae044b0ff658fe629dd67edd5ffe75d10e8Reid Spencer#ifndef LLVM_SUPPORT_CASTING_H 16551ccae044b0ff658fe629dd67edd5ffe75d10e8Reid Spencer#define LLVM_SUPPORT_CASTING_H 17589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner 18c7365a9ec96ff434d93d0d8052812283b33e537dReid Spencer#include <cassert> 19c7365a9ec96ff434d93d0d8052812283b33e537dReid Spencer 20d0fde30ce850b78371fd1386338350591f9ff494Brian Gaekenamespace llvm { 21d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke 22589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner//===----------------------------------------------------------------------===// 237e70829632f82de15db187845666aaca6e04b792Chris Lattner// isa<x> Support Templates 24589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner//===----------------------------------------------------------------------===// 25589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner 267e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<typename FromCl> struct isa_impl_cl; 277e70829632f82de15db187845666aaca6e04b792Chris Lattner 287e70829632f82de15db187845666aaca6e04b792Chris Lattner// Define a template that can be specialized by smart pointers to reflect the 297e70829632f82de15db187845666aaca6e04b792Chris Lattner// fact that they are automatically dereferenced, and are not involved with the 307e70829632f82de15db187845666aaca6e04b792Chris Lattner// template selection process... the default implementation is a noop. 317e70829632f82de15db187845666aaca6e04b792Chris Lattner// 327e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<typename From> struct simplify_type { 337e70829632f82de15db187845666aaca6e04b792Chris Lattner typedef From SimpleType; // The real type this represents... 347e70829632f82de15db187845666aaca6e04b792Chris Lattner 357e70829632f82de15db187845666aaca6e04b792Chris Lattner // An accessor to get the real value... 367e70829632f82de15db187845666aaca6e04b792Chris Lattner static SimpleType &getSimplifiedValue(From &Val) { return Val; } 377e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 387e70829632f82de15db187845666aaca6e04b792Chris Lattner 397e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<typename From> struct simplify_type<const From> { 407e70829632f82de15db187845666aaca6e04b792Chris Lattner typedef const From SimpleType; 417e70829632f82de15db187845666aaca6e04b792Chris Lattner static SimpleType &getSimplifiedValue(const From &Val) { 428b70b78ba489b090d9866e6a4084ab1e8613b527Chris Lattner return simplify_type<From>::getSimplifiedValue(static_cast<From&>(Val)); 437e70829632f82de15db187845666aaca6e04b792Chris Lattner } 447e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 457e70829632f82de15db187845666aaca6e04b792Chris Lattner 467e70829632f82de15db187845666aaca6e04b792Chris Lattner 47589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// isa<X> - Return true if the parameter to the template is an instance of the 48589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// template type argument. Used like this: 49589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// 507e70829632f82de15db187845666aaca6e04b792Chris Lattner// if (isa<Type*>(myVal)) { ... } 517e70829632f82de15db187845666aaca6e04b792Chris Lattner// 527e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate <typename To, typename From> 5363b3afa98460ce38a1c48d3c44ef6edfdaf37b77Misha Brukmaninline bool isa_impl(const From &Val) { 547e70829632f82de15db187845666aaca6e04b792Chris Lattner return To::classof(&Val); 557e70829632f82de15db187845666aaca6e04b792Chris Lattner} 567e70829632f82de15db187845666aaca6e04b792Chris Lattner 577e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<typename To, typename From, typename SimpleType> 587e70829632f82de15db187845666aaca6e04b792Chris Lattnerstruct isa_impl_wrap { 597e70829632f82de15db187845666aaca6e04b792Chris Lattner // When From != SimplifiedType, we can simplify the type some more by using 607e70829632f82de15db187845666aaca6e04b792Chris Lattner // the simplify_type template. 617e70829632f82de15db187845666aaca6e04b792Chris Lattner static bool doit(const From &Val) { 6263b3afa98460ce38a1c48d3c44ef6edfdaf37b77Misha Brukman return isa_impl_cl<const SimpleType>::template 637e70829632f82de15db187845666aaca6e04b792Chris Lattner isa<To>(simplify_type<const From>::getSimplifiedValue(Val)); 647e70829632f82de15db187845666aaca6e04b792Chris Lattner } 657e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 667e70829632f82de15db187845666aaca6e04b792Chris Lattner 677e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<typename To, typename FromTy> 687e70829632f82de15db187845666aaca6e04b792Chris Lattnerstruct isa_impl_wrap<To, const FromTy, const FromTy> { 697e70829632f82de15db187845666aaca6e04b792Chris Lattner // When From == SimpleType, we are as simple as we are going to get. 707e70829632f82de15db187845666aaca6e04b792Chris Lattner static bool doit(const FromTy &Val) { 717e70829632f82de15db187845666aaca6e04b792Chris Lattner return isa_impl<To,FromTy>(Val); 727e70829632f82de15db187845666aaca6e04b792Chris Lattner } 737e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 747e70829632f82de15db187845666aaca6e04b792Chris Lattner 757e70829632f82de15db187845666aaca6e04b792Chris Lattner// isa_impl_cl - Use class partial specialization to transform types to a single 76776f776838d6e2f83d899bc99452dc83779c341bChris Lattner// canonical form for isa_impl. 77589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// 787e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<typename FromCl> 797e70829632f82de15db187845666aaca6e04b792Chris Lattnerstruct isa_impl_cl { 807e70829632f82de15db187845666aaca6e04b792Chris Lattner template<class ToCl> 817e70829632f82de15db187845666aaca6e04b792Chris Lattner static bool isa(const FromCl &Val) { 827e70829632f82de15db187845666aaca6e04b792Chris Lattner return isa_impl_wrap<ToCl,const FromCl, 835a6d63ae29512d654c8c697f42f32f97b9dc010bChris Lattner typename simplify_type<const FromCl>::SimpleType>::doit(Val); 847e70829632f82de15db187845666aaca6e04b792Chris Lattner } 857e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 867e70829632f82de15db187845666aaca6e04b792Chris Lattner 877e70829632f82de15db187845666aaca6e04b792Chris Lattner// Specialization used to strip const qualifiers off of the FromCl type... 887e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<typename FromCl> 897e70829632f82de15db187845666aaca6e04b792Chris Lattnerstruct isa_impl_cl<const FromCl> { 907e70829632f82de15db187845666aaca6e04b792Chris Lattner template<class ToCl> 917e70829632f82de15db187845666aaca6e04b792Chris Lattner static bool isa(const FromCl &Val) { 927e70829632f82de15db187845666aaca6e04b792Chris Lattner return isa_impl_cl<FromCl>::template isa<ToCl>(Val); 937e70829632f82de15db187845666aaca6e04b792Chris Lattner } 947e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 957e70829632f82de15db187845666aaca6e04b792Chris Lattner 967e70829632f82de15db187845666aaca6e04b792Chris Lattner// Define pointer traits in terms of base traits... 977e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<class FromCl> 987e70829632f82de15db187845666aaca6e04b792Chris Lattnerstruct isa_impl_cl<FromCl*> { 997e70829632f82de15db187845666aaca6e04b792Chris Lattner template<class ToCl> 1007e70829632f82de15db187845666aaca6e04b792Chris Lattner static bool isa(FromCl *Val) { 1012cd91804ec4d631cc432dac2828d8ee0b1a3390fScott Michel return isa_impl_cl<FromCl>::template isa<ToCl>(*Val); 1027e70829632f82de15db187845666aaca6e04b792Chris Lattner } 1037e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 1047e70829632f82de15db187845666aaca6e04b792Chris Lattner 1057e70829632f82de15db187845666aaca6e04b792Chris Lattner// Define reference traits in terms of base traits... 1067e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<class FromCl> 1077e70829632f82de15db187845666aaca6e04b792Chris Lattnerstruct isa_impl_cl<FromCl&> { 1087e70829632f82de15db187845666aaca6e04b792Chris Lattner template<class ToCl> 1097e70829632f82de15db187845666aaca6e04b792Chris Lattner static bool isa(FromCl &Val) { 1107e70829632f82de15db187845666aaca6e04b792Chris Lattner return isa_impl_cl<FromCl>::template isa<ToCl>(&Val); 1117e70829632f82de15db187845666aaca6e04b792Chris Lattner } 1127e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 1137e70829632f82de15db187845666aaca6e04b792Chris Lattner 114589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattnertemplate <class X, class Y> 1157e70829632f82de15db187845666aaca6e04b792Chris Lattnerinline bool isa(const Y &Val) { 1167e70829632f82de15db187845666aaca6e04b792Chris Lattner return isa_impl_cl<Y>::template isa<X>(Val); 117589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner} 118589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner 1197e70829632f82de15db187845666aaca6e04b792Chris Lattner//===----------------------------------------------------------------------===// 1207e70829632f82de15db187845666aaca6e04b792Chris Lattner// cast<x> Support Templates 1217e70829632f82de15db187845666aaca6e04b792Chris Lattner//===----------------------------------------------------------------------===// 1227e70829632f82de15db187845666aaca6e04b792Chris Lattner 1237e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<class To, class From> struct cast_retty; 1247e70829632f82de15db187845666aaca6e04b792Chris Lattner 1257e70829632f82de15db187845666aaca6e04b792Chris Lattner 1267e70829632f82de15db187845666aaca6e04b792Chris Lattner// Calculate what type the 'cast' function should return, based on a requested 1277e70829632f82de15db187845666aaca6e04b792Chris Lattner// type of To and a source type of From. 1287e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<class To, class From> struct cast_retty_impl { 1297e70829632f82de15db187845666aaca6e04b792Chris Lattner typedef To& ret_type; // Normal case, return Ty& 1307e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 1317e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<class To, class From> struct cast_retty_impl<To, const From> { 1327e70829632f82de15db187845666aaca6e04b792Chris Lattner typedef const To &ret_type; // Normal case, return Ty& 1337e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 1347e70829632f82de15db187845666aaca6e04b792Chris Lattner 1357e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<class To, class From> struct cast_retty_impl<To, From*> { 1367e70829632f82de15db187845666aaca6e04b792Chris Lattner typedef To* ret_type; // Pointer arg case, return Ty* 1377e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 1387e70829632f82de15db187845666aaca6e04b792Chris Lattner 1397e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<class To, class From> struct cast_retty_impl<To, const From*> { 1407e70829632f82de15db187845666aaca6e04b792Chris Lattner typedef const To* ret_type; // Constant pointer arg case, return const Ty* 1417e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 1427e70829632f82de15db187845666aaca6e04b792Chris Lattner 1437e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<class To, class From> struct cast_retty_impl<To, const From*const> { 1447e70829632f82de15db187845666aaca6e04b792Chris Lattner typedef const To* ret_type; // Constant pointer arg case, return const Ty* 1457e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 1467e70829632f82de15db187845666aaca6e04b792Chris Lattner 1477e70829632f82de15db187845666aaca6e04b792Chris Lattner 1487e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<class To, class From, class SimpleFrom> 1497e70829632f82de15db187845666aaca6e04b792Chris Lattnerstruct cast_retty_wrap { 1507e70829632f82de15db187845666aaca6e04b792Chris Lattner // When the simplified type and the from type are not the same, use the type 1517e70829632f82de15db187845666aaca6e04b792Chris Lattner // simplifier to reduce the type, then reuse cast_retty_impl to get the 1527e70829632f82de15db187845666aaca6e04b792Chris Lattner // resultant type. 1537e70829632f82de15db187845666aaca6e04b792Chris Lattner typedef typename cast_retty<To, SimpleFrom>::ret_type ret_type; 1547e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 1557e70829632f82de15db187845666aaca6e04b792Chris Lattner 1567e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<class To, class FromTy> 1577e70829632f82de15db187845666aaca6e04b792Chris Lattnerstruct cast_retty_wrap<To, FromTy, FromTy> { 1587e70829632f82de15db187845666aaca6e04b792Chris Lattner // When the simplified type is equal to the from type, use it directly. 1597e70829632f82de15db187845666aaca6e04b792Chris Lattner typedef typename cast_retty_impl<To,FromTy>::ret_type ret_type; 1607e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 1617e70829632f82de15db187845666aaca6e04b792Chris Lattner 1627e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<class To, class From> 1637e70829632f82de15db187845666aaca6e04b792Chris Lattnerstruct cast_retty { 16463b3afa98460ce38a1c48d3c44ef6edfdaf37b77Misha Brukman typedef typename cast_retty_wrap<To, From, 1655a6d63ae29512d654c8c697f42f32f97b9dc010bChris Lattner typename simplify_type<From>::SimpleType>::ret_type ret_type; 1667e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 1677e70829632f82de15db187845666aaca6e04b792Chris Lattner 1687e70829632f82de15db187845666aaca6e04b792Chris Lattner// Ensure the non-simple values are converted using the simplify_type template 1697e70829632f82de15db187845666aaca6e04b792Chris Lattner// that may be specialized by smart pointers... 1707e70829632f82de15db187845666aaca6e04b792Chris Lattner// 1717e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<class To, class From, class SimpleFrom> struct cast_convert_val { 1727e70829632f82de15db187845666aaca6e04b792Chris Lattner // This is not a simple type, use the template to simplify it... 1735a6d63ae29512d654c8c697f42f32f97b9dc010bChris Lattner static typename cast_retty<To, From>::ret_type doit(const From &Val) { 1747e70829632f82de15db187845666aaca6e04b792Chris Lattner return cast_convert_val<To, SimpleFrom, 1755a6d63ae29512d654c8c697f42f32f97b9dc010bChris Lattner typename simplify_type<SimpleFrom>::SimpleType>::doit( 1767e70829632f82de15db187845666aaca6e04b792Chris Lattner simplify_type<From>::getSimplifiedValue(Val)); 1777e70829632f82de15db187845666aaca6e04b792Chris Lattner } 1787e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 1797e70829632f82de15db187845666aaca6e04b792Chris Lattner 1807e70829632f82de15db187845666aaca6e04b792Chris Lattnertemplate<class To, class FromTy> struct cast_convert_val<To,FromTy,FromTy> { 1817e70829632f82de15db187845666aaca6e04b792Chris Lattner // This _is_ a simple type, just cast it. 1825a6d63ae29512d654c8c697f42f32f97b9dc010bChris Lattner static typename cast_retty<To, FromTy>::ret_type doit(const FromTy &Val) { 1833a3134ab12f3aa65f9791f702a73f6d0b2af423fChris Lattner typename cast_retty<To, FromTy>::ret_type Res2 1843a3134ab12f3aa65f9791f702a73f6d0b2af423fChris Lattner = (typename cast_retty<To, FromTy>::ret_type)const_cast<FromTy&>(Val); 1853a3134ab12f3aa65f9791f702a73f6d0b2af423fChris Lattner return Res2; 1867e70829632f82de15db187845666aaca6e04b792Chris Lattner } 1877e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 1887e70829632f82de15db187845666aaca6e04b792Chris Lattner 1897e70829632f82de15db187845666aaca6e04b792Chris Lattner 190589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner 191589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// cast<X> - Return the argument parameter cast to the specified type. This 192589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// casting operator asserts that the type is correct, so it does not return null 193589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// on failure. But it will correctly return NULL when the input is NULL. 194589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// Used Like this: 195589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// 1967e70829632f82de15db187845666aaca6e04b792Chris Lattner// cast<Instruction>(myVal)->getParent() 197589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// 198589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattnertemplate <class X, class Y> 1995a6d63ae29512d654c8c697f42f32f97b9dc010bChris Lattnerinline typename cast_retty<X, Y>::ret_type cast(const Y &Val) { 20088d942d8983aadecae477fee523c23312d194515Misha Brukman assert(isa<X>(Val) && "cast<Ty>() argument of incompatible type!"); 2015a6d63ae29512d654c8c697f42f32f97b9dc010bChris Lattner return cast_convert_val<X, Y, 2025a6d63ae29512d654c8c697f42f32f97b9dc010bChris Lattner typename simplify_type<Y>::SimpleType>::doit(Val); 203589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner} 204589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner 205589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// cast_or_null<X> - Functionally identical to cast, except that a null value is 206589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// accepted. 207589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// 208589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattnertemplate <class X, class Y> 2099a0b165cb58cb5cf49cb3a143c302029f389acb2Argyrios Kyrtzidisinline typename cast_retty<X, Y*>::ret_type cast_or_null(Y *Val) { 2109a0b165cb58cb5cf49cb3a143c302029f389acb2Argyrios Kyrtzidis if (Val == 0) return 0; 21188d942d8983aadecae477fee523c23312d194515Misha Brukman assert(isa<X>(Val) && "cast_or_null<Ty>() argument of incompatible type!"); 2127e70829632f82de15db187845666aaca6e04b792Chris Lattner return cast<X>(Val); 213589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner} 214589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner 215589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner 216589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// dyn_cast<X> - Return the argument parameter cast to the specified type. This 217589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// casting operator returns null if the argument is of the wrong type, so it can 218589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// be used to test for a type as well as cast if successful. This should be 219589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// used in the context of an if statement like this: 220589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// 2211ff1da7ac9bff43ba24445ff30ba2fd79bd95cd7Chris Lattner// if (const Instruction *I = dyn_cast<Instruction>(myVal)) { ... } 222589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// 223589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner 224589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattnertemplate <class X, class Y> 225917365bef1cfb8493558b76f8e6ceb1e76eba2c5Gabor Greifinline typename cast_retty<X, Y>::ret_type dyn_cast(const Y &Val) { 2269a0b165cb58cb5cf49cb3a143c302029f389acb2Argyrios Kyrtzidis return isa<X>(Val) ? cast<X, Y>(Val) : 0; 227589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner} 228589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner 229589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// dyn_cast_or_null<X> - Functionally identical to dyn_cast, except that a null 230589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// value is accepted. 231589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner// 232589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattnertemplate <class X, class Y> 233917365bef1cfb8493558b76f8e6ceb1e76eba2c5Gabor Greifinline typename cast_retty<X, Y>::ret_type dyn_cast_or_null(const Y &Val) { 2349a0b165cb58cb5cf49cb3a143c302029f389acb2Argyrios Kyrtzidis return (Val && isa<X>(Val)) ? cast<X, Y>(Val) : 0; 2357e70829632f82de15db187845666aaca6e04b792Chris Lattner} 2367e70829632f82de15db187845666aaca6e04b792Chris Lattner 2377e70829632f82de15db187845666aaca6e04b792Chris Lattner 2387e70829632f82de15db187845666aaca6e04b792Chris Lattner#ifdef DEBUG_CAST_OPERATORS 239103289e9383ad1eb66caf28c9b166aebce963a35Chris Lattner#include "llvm/Support/raw_ostream.h" 2407e70829632f82de15db187845666aaca6e04b792Chris Lattner 2417e70829632f82de15db187845666aaca6e04b792Chris Lattnerstruct bar { 2427e70829632f82de15db187845666aaca6e04b792Chris Lattner bar() {} 2437e70829632f82de15db187845666aaca6e04b792Chris Lattnerprivate: 2447e70829632f82de15db187845666aaca6e04b792Chris Lattner bar(const bar &); 2457e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 2467e70829632f82de15db187845666aaca6e04b792Chris Lattnerstruct foo { 2477e70829632f82de15db187845666aaca6e04b792Chris Lattner void ext() const; 2487e70829632f82de15db187845666aaca6e04b792Chris Lattner /* static bool classof(const bar *X) { 249e81561909d128c6e2d8033cb5465a49b2596b26aBill Wendling cerr << "Classof: " << X << "\n"; 2507e70829632f82de15db187845666aaca6e04b792Chris Lattner return true; 2517e70829632f82de15db187845666aaca6e04b792Chris Lattner }*/ 2527e70829632f82de15db187845666aaca6e04b792Chris Lattner}; 2537e70829632f82de15db187845666aaca6e04b792Chris Lattner 25463b3afa98460ce38a1c48d3c44ef6edfdaf37b77Misha Brukmantemplate <> inline bool isa_impl<foo,bar>(const bar &Val) { 2550ff129f061233b724abe22fe048f06bcb06cd308David Greene dbgs() << "Classof: " << &Val << "\n"; 2567e70829632f82de15db187845666aaca6e04b792Chris Lattner return true; 2577e70829632f82de15db187845666aaca6e04b792Chris Lattner} 2587e70829632f82de15db187845666aaca6e04b792Chris Lattner 2597e70829632f82de15db187845666aaca6e04b792Chris Lattner 2607e70829632f82de15db187845666aaca6e04b792Chris Lattnerbar *fub(); 2617e70829632f82de15db187845666aaca6e04b792Chris Lattnervoid test(bar &B1, const bar *B2) { 2627e70829632f82de15db187845666aaca6e04b792Chris Lattner // test various configurations of const 2637e70829632f82de15db187845666aaca6e04b792Chris Lattner const bar &B3 = B1; 2647e70829632f82de15db187845666aaca6e04b792Chris Lattner const bar *const B4 = B2; 2657e70829632f82de15db187845666aaca6e04b792Chris Lattner 2667e70829632f82de15db187845666aaca6e04b792Chris Lattner // test isa 2677e70829632f82de15db187845666aaca6e04b792Chris Lattner if (!isa<foo>(B1)) return; 2687e70829632f82de15db187845666aaca6e04b792Chris Lattner if (!isa<foo>(B2)) return; 2697e70829632f82de15db187845666aaca6e04b792Chris Lattner if (!isa<foo>(B3)) return; 2707e70829632f82de15db187845666aaca6e04b792Chris Lattner if (!isa<foo>(B4)) return; 2717e70829632f82de15db187845666aaca6e04b792Chris Lattner 2727e70829632f82de15db187845666aaca6e04b792Chris Lattner // test cast 2737e70829632f82de15db187845666aaca6e04b792Chris Lattner foo &F1 = cast<foo>(B1); 2747e70829632f82de15db187845666aaca6e04b792Chris Lattner const foo *F3 = cast<foo>(B2); 2757e70829632f82de15db187845666aaca6e04b792Chris Lattner const foo *F4 = cast<foo>(B2); 2767e70829632f82de15db187845666aaca6e04b792Chris Lattner const foo &F8 = cast<foo>(B3); 2777e70829632f82de15db187845666aaca6e04b792Chris Lattner const foo *F9 = cast<foo>(B4); 2787e70829632f82de15db187845666aaca6e04b792Chris Lattner foo *F10 = cast<foo>(fub()); 2797e70829632f82de15db187845666aaca6e04b792Chris Lattner 2807e70829632f82de15db187845666aaca6e04b792Chris Lattner // test cast_or_null 2817e70829632f82de15db187845666aaca6e04b792Chris Lattner const foo *F11 = cast_or_null<foo>(B2); 2827e70829632f82de15db187845666aaca6e04b792Chris Lattner const foo *F12 = cast_or_null<foo>(B2); 2837e70829632f82de15db187845666aaca6e04b792Chris Lattner const foo *F13 = cast_or_null<foo>(B4); 2847e70829632f82de15db187845666aaca6e04b792Chris Lattner const foo *F14 = cast_or_null<foo>(fub()); // Shouldn't print. 28563b3afa98460ce38a1c48d3c44ef6edfdaf37b77Misha Brukman 2867e70829632f82de15db187845666aaca6e04b792Chris Lattner // These lines are errors... 2877e70829632f82de15db187845666aaca6e04b792Chris Lattner //foo *F20 = cast<foo>(B2); // Yields const foo* 2887e70829632f82de15db187845666aaca6e04b792Chris Lattner //foo &F21 = cast<foo>(B3); // Yields const foo& 2897e70829632f82de15db187845666aaca6e04b792Chris Lattner //foo *F22 = cast<foo>(B4); // Yields const foo* 2907e70829632f82de15db187845666aaca6e04b792Chris Lattner //foo &F23 = cast_or_null<foo>(B1); 2917e70829632f82de15db187845666aaca6e04b792Chris Lattner //const foo &F24 = cast_or_null<foo>(B3); 2927e70829632f82de15db187845666aaca6e04b792Chris Lattner} 2937e70829632f82de15db187845666aaca6e04b792Chris Lattner 2947e70829632f82de15db187845666aaca6e04b792Chris Lattnerbar *fub() { return 0; } 2957e70829632f82de15db187845666aaca6e04b792Chris Lattnervoid main() { 2967e70829632f82de15db187845666aaca6e04b792Chris Lattner bar B; 2977e70829632f82de15db187845666aaca6e04b792Chris Lattner test(B, &B); 298589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner} 299589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner 300589df88ba03a81b2b3dc9d084c191a3a74724ecdChris Lattner#endif 3017e70829632f82de15db187845666aaca6e04b792Chris Lattner 302d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke} // End llvm namespace 303d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke 3047e70829632f82de15db187845666aaca6e04b792Chris Lattner#endif 305