returning in some static piece of memory and arrange
to return to it before tail jumping from the adjustor thunk.
*/
-__asm__ (
- ".globl " UNDERSCORE "obscure_ccall_ret_code\n"
- UNDERSCORE "obscure_ccall_ret_code:\n\t"
- "addl $0x4, %esp\n\t"
- "ret"
- );
+static void GNUC3_ATTRIBUTE(used) obscure_ccall_wrapper(void)
+{
+ __asm__ (
+ ".globl " UNDERSCORE "obscure_ccall_ret_code\n"
+ UNDERSCORE "obscure_ccall_ret_code:\n\t"
+ "addl $0x4, %esp\n\t"
+ "ret"
+ );
+}
extern void obscure_ccall_ret_code(void);
+
+#if defined(openbsd_HOST_OS)
+static unsigned char *obscure_ccall_ret_code_dyn;
+#endif
+
#endif
#if defined(x86_64_HOST_ARCH)
-__asm__ (
+static void GNUC3_ATTRIBUTE(used) obscure_ccall_wrapper(void)
+{
+ __asm__ (
".globl " UNDERSCORE "obscure_ccall_ret_code\n"
UNDERSCORE "obscure_ccall_ret_code:\n\t"
"addq $0x8, %rsp\n\t"
"ret"
);
+}
extern void obscure_ccall_ret_code(void);
#endif
*((StgFunPtr*)(adj_code + 0x06)) = (StgFunPtr)wptr;
adj_code[0x0a] = (unsigned char)0x68; /* pushl obscure_ccall_ret_code */
- *((StgFunPtr*)(adj_code + 0x0b)) = (StgFunPtr)obscure_ccall_ret_code;
+ *((StgFunPtr*)(adj_code + 0x0b)) =
+#if !defined(openbsd_HOST_OS)
+ (StgFunPtr)obscure_ccall_ret_code;
+#else
+ (StgFunPtr)obscure_ccall_ret_code_dyn;
+#endif
adj_code[0x0f] = (unsigned char)0xff; /* jmp *%eax */
adj_code[0x10] = (unsigned char)0xe0;
void
initAdjustor(void)
{
+#if defined(i386_HOST_ARCH) && defined(openbsd_HOST_OS)
+ obscure_ccall_ret_code_dyn = mallocBytesRWX(4);
+ obscure_ccall_ret_code_dyn[0] = ((unsigned char *)obscure_ccall_ret_code)[0];
+ obscure_ccall_ret_code_dyn[1] = ((unsigned char *)obscure_ccall_ret_code)[1];
+ obscure_ccall_ret_code_dyn[2] = ((unsigned char *)obscure_ccall_ret_code)[2];
+ obscure_ccall_ret_code_dyn[3] = ((unsigned char *)obscure_ccall_ret_code)[3];
+#endif
}