mirror of
https://github.com/capstone-engine/llvm-capstone.git
synced 2024-12-14 03:29:57 +00:00
49 lines
1.7 KiB
C
49 lines
1.7 KiB
C
/* ===----- trampoline_setup.c - Implement __trampoline_setup -------------===
|
|
*
|
|
* The LLVM Compiler Infrastructure
|
|
*
|
|
* This file is distributed under the University of Illinois Open Source
|
|
* License. See LICENSE.TXT for details.
|
|
*
|
|
* ===----------------------------------------------------------------------===
|
|
*/
|
|
|
|
#include <stdint.h>
|
|
#include <stdlib.h>
|
|
|
|
extern void __clear_cache(void* start, void* end);
|
|
|
|
/*
|
|
* The ppc compiler generates calls to __trampoline_setup() when creating
|
|
* trampoline functions on the stack for use with nested functions.
|
|
* This function creates a custom 40-byte trampoline function on the stack
|
|
* which loads r11 with a pointer to the outer function's locals
|
|
* and then jumps to the target nested function.
|
|
*/
|
|
|
|
#if __ppc__
|
|
void __trampoline_setup(uint32_t* trampOnStack, int trampSizeAllocated,
|
|
const void* realFunc, void* localsPtr)
|
|
{
|
|
/* should never happen, but if compiler did not allocate */
|
|
/* enough space on stack for the trampoline, abort */
|
|
if ( trampSizeAllocated < 40 )
|
|
abort();
|
|
|
|
/* create trampoline */
|
|
trampOnStack[0] = 0x7c0802a6; /* mflr r0 */
|
|
trampOnStack[1] = 0x4800000d; /* bl Lbase */
|
|
trampOnStack[2] = (uint32_t)realFunc;
|
|
trampOnStack[3] = (uint32_t)localsPtr;
|
|
trampOnStack[4] = 0x7d6802a6; /* Lbase: mflr r11 */
|
|
trampOnStack[5] = 0x818b0000; /* lwz r12,0(r11) */
|
|
trampOnStack[6] = 0x7c0803a6; /* mtlr r0 */
|
|
trampOnStack[7] = 0x7d8903a6; /* mtctr r12 */
|
|
trampOnStack[8] = 0x816b0004; /* lwz r11,4(r11) */
|
|
trampOnStack[9] = 0x4e800420; /* bctr */
|
|
|
|
/* clear instruction cache */
|
|
__clear_cache(trampOnStack, &trampOnStack[10]);
|
|
}
|
|
#endif /* __ppc__ */
|