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Diffstat (limited to 'contrib/compiler-rt/lib/enable_execute_stack.c')
-rw-r--r--contrib/compiler-rt/lib/enable_execute_stack.c59
1 files changed, 0 insertions, 59 deletions
diff --git a/contrib/compiler-rt/lib/enable_execute_stack.c b/contrib/compiler-rt/lib/enable_execute_stack.c
deleted file mode 100644
index 278ca246f537..000000000000
--- a/contrib/compiler-rt/lib/enable_execute_stack.c
+++ /dev/null
@@ -1,59 +0,0 @@
-/* ===-- enable_execute_stack.c - Implement __enable_execute_stack ---------===
- *
- * The LLVM Compiler Infrastructure
- *
- * This file is dual licensed under the MIT and the University of Illinois Open
- * Source Licenses. See LICENSE.TXT for details.
- *
- * ===----------------------------------------------------------------------===
- */
-
-#include "int_lib.h"
-
-#include <sys/mman.h>
-
-/* #include "config.h"
- * FIXME: CMake - include when cmake system is ready.
- * Remove #define HAVE_SYSCONF 1 line.
- */
-#define HAVE_SYSCONF 1
-
-#ifndef __APPLE__
-#include <unistd.h>
-#endif /* __APPLE__ */
-
-#if __LP64__
- #define TRAMPOLINE_SIZE 48
-#else
- #define TRAMPOLINE_SIZE 40
-#endif
-
-/*
- * The compiler generates calls to __enable_execute_stack() when creating
- * trampoline functions on the stack for use with nested functions.
- * It is expected to mark the page(s) containing the address
- * and the next 48 bytes as executable. Since the stack is normally rw-
- * that means changing the protection on those page(s) to rwx.
- */
-
-void __enable_execute_stack(void* addr)
-{
-
-#if __APPLE__
- /* On Darwin, pagesize is always 4096 bytes */
- const uintptr_t pageSize = 4096;
-#elif !defined(HAVE_SYSCONF)
-#error "HAVE_SYSCONF not defined! See enable_execute_stack.c"
-#else
- const uintptr_t pageSize = sysconf(_SC_PAGESIZE);
-#endif /* __APPLE__ */
-
- const uintptr_t pageAlignMask = ~(pageSize-1);
- uintptr_t p = (uintptr_t)addr;
- unsigned char* startPage = (unsigned char*)(p & pageAlignMask);
- unsigned char* endPage = (unsigned char*)((p+TRAMPOLINE_SIZE+pageSize) & pageAlignMask);
- size_t length = endPage - startPage;
- (void) mprotect((void *)startPage, length, PROT_READ | PROT_WRITE | PROT_EXEC);
-}
-
-