Implement ARM floating point exception emulation

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4166 c046a42c-6fe2-441c-8c8c-71466251a162
This commit is contained in:
aurel32 2008-04-07 20:30:53 +00:00
parent 26fb5e48d9
commit 6d9a42be17
2 changed files with 58 additions and 2 deletions

View File

@ -378,19 +378,68 @@ void cpu_loop(CPUARMState *env)
{
TaskState *ts = env->opaque;
uint32_t opcode;
int rc;
/* we handle the FPU emulation here, as Linux */
/* we get the opcode */
/* FIXME - what to do if get_user() fails? */
get_user_u32(opcode, env->regs[15]);
if (EmulateAll(opcode, &ts->fpa, env) == 0) {
rc = EmulateAll(opcode, &ts->fpa, env);
if (rc == 0) { /* illegal instruction */
info.si_signo = SIGILL;
info.si_errno = 0;
info.si_code = TARGET_ILL_ILLOPN;
info._sifields._sigfault._addr = env->regs[15];
queue_signal(info.si_signo, &info);
} else {
} else if (rc < 0) { /* FP exception */
int arm_fpe=0;
/* translate softfloat flags to FPSR flags */
if (-rc & float_flag_invalid)
arm_fpe |= BIT_IOC;
if (-rc & float_flag_divbyzero)
arm_fpe |= BIT_DZC;
if (-rc & float_flag_overflow)
arm_fpe |= BIT_OFC;
if (-rc & float_flag_underflow)
arm_fpe |= BIT_UFC;
if (-rc & float_flag_inexact)
arm_fpe |= BIT_IXC;
FPSR fpsr = ts->fpa.fpsr;
//printf("fpsr 0x%x, arm_fpe 0x%x\n",fpsr,arm_fpe);
if (fpsr & (arm_fpe << 16)) { /* exception enabled? */
info.si_signo = SIGFPE;
info.si_errno = 0;
/* ordered by priority, least first */
if (arm_fpe & BIT_IXC) info.si_code = TARGET_FPE_FLTRES;
if (arm_fpe & BIT_UFC) info.si_code = TARGET_FPE_FLTUND;
if (arm_fpe & BIT_OFC) info.si_code = TARGET_FPE_FLTOVF;
if (arm_fpe & BIT_DZC) info.si_code = TARGET_FPE_FLTDIV;
if (arm_fpe & BIT_IOC) info.si_code = TARGET_FPE_FLTINV;
info._sifields._sigfault._addr = env->regs[15];
queue_signal(info.si_signo, &info);
} else {
env->regs[15] += 4;
}
/* accumulate unenabled exceptions */
if ((!(fpsr & BIT_IXE)) && (arm_fpe & BIT_IXC))
fpsr |= BIT_IXC;
if ((!(fpsr & BIT_UFE)) && (arm_fpe & BIT_UFC))
fpsr |= BIT_UFC;
if ((!(fpsr & BIT_OFE)) && (arm_fpe & BIT_OFC))
fpsr |= BIT_OFC;
if ((!(fpsr & BIT_DZE)) && (arm_fpe & BIT_DZC))
fpsr |= BIT_DZC;
if ((!(fpsr & BIT_IOE)) && (arm_fpe & BIT_IOC))
fpsr |= BIT_IOC;
ts->fpa.fpsr=fpsr;
} else { /* everything OK */
/* increment PC */
env->regs[15] += 4;
}

View File

@ -162,6 +162,8 @@ unsigned int EmulateAll(unsigned int opcode, FPA11* qfpa, CPUARMState* qregs)
fpa11->initflag = 1;
}
set_float_exception_flags(0, &fpa11->fp_status);
if (TEST_OPCODE(opcode,MASK_CPRT))
{
//fprintf(stderr,"emulating CPRT\n");
@ -191,6 +193,11 @@ unsigned int EmulateAll(unsigned int opcode, FPA11* qfpa, CPUARMState* qregs)
}
// restore_flags(flags);
if(nRc == 1 && get_float_exception_flags(&fpa11->fp_status))
{
//printf("fef 0x%x\n",float_exception_flags);
nRc=-get_float_exception_flags(&fpa11->fp_status);
}
//printf("returning %d\n",nRc);
return(nRc);