f287008791
- Fiddling with abort directly is annoying given the way we use system includes, although it would be nice to fix this so we could make sure calling abort directly is verboten. llvm-svn: 100014
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 )
|
|
compilerrt_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__ */
|