OpenHome/venv/Lib/site-packages/greenlet/platform/switch_arm32_gcc.h
2021-07-21 21:33:05 +02:00

80 lines
2.4 KiB
C

/*
* this is the internal transfer function.
*
* HISTORY
* 14-Aug-06 File creation. Ported from Arm Thumb. Sylvain Baro
* 3-Sep-06 Commented out saving of r1-r3 (r4 already commented out) as I
* read that these do not need to be saved. Also added notes and
* errors related to the frame pointer. Richard Tew.
*
* NOTES
*
* It is not possible to detect if fp is used or not, so the supplied
* switch function needs to support it, so that you can remove it if
* it does not apply to you.
*
* POSSIBLE ERRORS
*
* "fp cannot be used in asm here"
*
* - Try commenting out "fp" in REGS_TO_SAVE.
*
*/
#define STACK_REFPLUS 1
#ifdef SLP_EVAL
#define STACK_MAGIC 0
#define REG_SP "sp"
#define REG_SPSP "sp,sp"
#ifdef __thumb__
#define REG_FP "r7"
#define REG_FPFP "r7,r7"
#define REGS_TO_SAVE_GENERAL "r4", "r5", "r6", "r8", "r9", "r10", "r11", "lr"
#else
#define REG_FP "fp"
#define REG_FPFP "fp,fp"
#define REGS_TO_SAVE_GENERAL "r4", "r5", "r6", "r7", "r8", "r9", "r10", "lr"
#endif
#if defined(__SOFTFP__)
#define REGS_TO_SAVE REGS_TO_SAVE_GENERAL
#elif defined(__VFP_FP__)
#define REGS_TO_SAVE REGS_TO_SAVE_GENERAL, "d8", "d9", "d10", "d11", \
"d12", "d13", "d14", "d15"
#elif defined(__MAVERICK__)
#define REGS_TO_SAVE REGS_TO_SAVE_GENERAL, "mvf4", "mvf5", "mvf6", "mvf7", \
"mvf8", "mvf9", "mvf10", "mvf11", \
"mvf12", "mvf13", "mvf14", "mvf15"
#else
#define REGS_TO_SAVE REGS_TO_SAVE_GENERAL, "f4", "f5", "f6", "f7"
#endif
static int
#ifdef __GNUC__
__attribute__((optimize("no-omit-frame-pointer")))
#endif
slp_switch(void)
{
void *fp;
register int *stackref, stsizediff;
int result;
__asm__ volatile ("" : : : REGS_TO_SAVE);
__asm__ volatile ("mov r0," REG_FP "\n\tstr r0,%0" : "=m" (fp) : : "r0");
__asm__ ("mov %0," REG_SP : "=r" (stackref));
{
SLP_SAVE_STATE(stackref, stsizediff);
__asm__ volatile (
"add " REG_SPSP ",%0\n"
"add " REG_FPFP ",%0\n"
:
: "r" (stsizediff)
);
SLP_RESTORE_STATE();
}
__asm__ volatile ("ldr r0,%1\n\tmov " REG_FP ",r0\n\tmov %0, #0" : "=r" (result) : "m" (fp) : "r0");
__asm__ volatile ("" : : : REGS_TO_SAVE);
return result;
}
#endif