1 //===- SearchForAddressOfSpecialSymbol.cpp - Function addresses -*- 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 pulls the addresses of certain symbols out of the linker. It must 11 // include as few header files as possible because it declares the symbols as 12 // void*, which would conflict with the actual symbol type if any header 13 // declared it. 14 // 15 //===----------------------------------------------------------------------===// 16 17 #include <string.h> 18 19 // Must declare the symbols in the global namespace. DoSearch(const char * symbolName)20static void *DoSearch(const char* symbolName) { 21 #define EXPLICIT_SYMBOL(SYM) \ 22 extern void *SYM; if (!strcmp(symbolName, #SYM)) return &SYM 23 24 // If this is darwin, it has some funky issues, try to solve them here. Some 25 // important symbols are marked 'private external' which doesn't allow 26 // SearchForAddressOfSymbol to find them. As such, we special case them here, 27 // there is only a small handful of them. 28 29 #ifdef __APPLE__ 30 { 31 EXPLICIT_SYMBOL(__ashldi3); 32 EXPLICIT_SYMBOL(__ashrdi3); 33 EXPLICIT_SYMBOL(__cmpdi2); 34 EXPLICIT_SYMBOL(__divdi3); 35 EXPLICIT_SYMBOL(__fixdfdi); 36 EXPLICIT_SYMBOL(__fixsfdi); 37 EXPLICIT_SYMBOL(__fixunsdfdi); 38 EXPLICIT_SYMBOL(__fixunssfdi); 39 EXPLICIT_SYMBOL(__floatdidf); 40 EXPLICIT_SYMBOL(__floatdisf); 41 EXPLICIT_SYMBOL(__lshrdi3); 42 EXPLICIT_SYMBOL(__moddi3); 43 EXPLICIT_SYMBOL(__udivdi3); 44 EXPLICIT_SYMBOL(__umoddi3); 45 46 // __eprintf is sometimes used for assert() handling on x86. 47 // 48 // FIXME: Currently disabled when using Clang, as we don't always have our 49 // runtime support libraries available. 50 #ifndef __clang__ 51 #ifdef __i386__ 52 EXPLICIT_SYMBOL(__eprintf); 53 #endif 54 #endif 55 } 56 #endif 57 58 #ifdef __CYGWIN__ 59 { 60 EXPLICIT_SYMBOL(_alloca); 61 EXPLICIT_SYMBOL(__main); 62 } 63 #endif 64 65 #undef EXPLICIT_SYMBOL 66 return 0; 67 } 68 69 namespace llvm { SearchForAddressOfSpecialSymbol(const char * symbolName)70void *SearchForAddressOfSpecialSymbol(const char* symbolName) { 71 return DoSearch(symbolName); 72 } 73 } // namespace llvm 74