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<rdar://problem/7813254> check enable_execute_stack implementation 

llvm-svn: 100036
This commit is contained in:
Nick Kledzik 2010-03-31 19:52:01 +00:00
parent 74729ae094
commit b3d3ec7091
1 changed files with 6 additions and 1 deletions
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7
compiler-rt/lib/enable_execute_stack.c
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@ -21,6 +21,11 @@
#include <unistd.h> #include <unistd.h>
#endif /* __APPLE__ */ #endif /* __APPLE__ */
#if __LP64__
#define TRAMPOLINE_SIZE 48
#else
#define TRAMPOLINE_SIZE 40
#endif
/* /*
* The compiler generates calls to __enable_execute_stack() when creating * The compiler generates calls to __enable_execute_stack() when creating
@ -45,7 +50,7 @@ void __enable_execute_stack(void* addr)
const uintptr_t pageAlignMask = ~(pageSize-1); const uintptr_t pageAlignMask = ~(pageSize-1);
uintptr_t p = (uintptr_t)addr; uintptr_t p = (uintptr_t)addr;
unsigned char* startPage = (unsigned char*)(p & pageAlignMask); unsigned char* startPage = (unsigned char*)(p & pageAlignMask);
unsigned char* endPage = (unsigned char*)((p+48+pageSize) & pageAlignMask); unsigned char* endPage = (unsigned char*)((p+TRAMPOLINE_SIZE+pageSize) & pageAlignMask);
size_t length = endPage - startPage; size_t length = endPage - startPage;
(void) mprotect((void *)startPage, length, PROT_READ | PROT_WRITE | PROT_EXEC); (void) mprotect((void *)startPage, length, PROT_READ | PROT_WRITE | PROT_EXEC);
} }