- ucontext_t *_uc;
- mcontext_t *_mc;
- greg_t *_gregs;
- u1 *pv;
- u1 *sp;
- u1 *ra;
- u1 *xpc;
- unsigned int cause;
- u4 mcode;
- int d;
- int s1;
- int16_t disp;
- intptr_t val;
- intptr_t addr;
- int type;
-
- _uc = (struct ucontext *) _p;
- _mc = &_uc->uc_mcontext;
-
-#if defined(__UCLIBC__)
- _gregs = _mc->gpregs;
-#else
- _gregs = _mc->gregs;
-#endif
-
- /* In glibc's ucontext.h the registers are defined as long long,
- even for MIPS32, so we cast them. This is not the case for
- uClibc. */
-
- pv = (u1 *) (ptrint) _gregs[REG_PV];
- sp = (u1 *) (ptrint) _gregs[REG_SP];
- ra = (u1 *) (ptrint) _gregs[REG_RA]; /* this is correct for leafs */
-
-#if !defined(__UCLIBC__)
-# if ((__GLIBC__ == 2) && (__GLIBC_MINOR__ < 5))
- /* NOTE: We only need this for pre glibc-2.5. */
-
- xpc = (u1 *) (ptrint) _mc->pc;
-
- /* get the cause of this exception */
-
- cause = _mc->cause;
-
- /* check the cause to find the faulting instruction */
-
- /* TODO: use defines for that stuff */
-
- switch (cause & 0x0000003c) {
- case 0x00000008:
- /* TLBL: XPC is ok */
- break;
-
- case 0x00000010:
- /* AdEL: XPC is of the following instruction */
- xpc = xpc - 4;
- break;
- }
-# else
- xpc = (u1 *) (ptrint) _mc->pc;
-# endif
-#else
- xpc = (u1 *) (ptrint) _gregs[CTX_EPC];
-#endif
-
- /* get exception-throwing instruction */
-
- mcode = *((u4 *) xpc);
-
- d = M_ITYPE_GET_RT(mcode);
- s1 = M_ITYPE_GET_RS(mcode);
- disp = M_ITYPE_GET_IMM(mcode);
-
- /* check for special-load */
-
- if (s1 == REG_ZERO) {
- /* we use the exception type as load displacement */
-
- type = disp;
- val = _gregs[d];
-
- if (type == TRAP_COMPILER) {
- /* The XPC is the RA minus 4, because the RA points to the
- instruction after the call. */
-
- xpc = ra - 4;
- }
- }
- else {
- /* This is a normal NPE: addr must be NULL and the NPE-type
- define is 0. */
-
- addr = _gregs[s1];
- type = (int) addr;
- val = 0;
- }