Multiplication of Q15 fractional halfword vectors was incorrect in the
previous implementation of mipsdsp_rndq15_mul_q15_q15. It failed to take
element signs into account. This change fixes it, and it adds a test case
for it.
The change also removes unnecessary cast in the function
mipsdsp_mul_q15_q15_overflowflag21().
Signed-off-by: Petar Jovanovic <petar.jovanovic@imgtec.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
temp = 0x7FFFFFFF;
set_DSPControl_overflow_flag(1, 21, env);
} else {
- temp = ((int32_t)(int16_t)a * (int32_t)(int16_t)b) << 1;
+ temp = ((int16_t)a * (int16_t)b) << 1;
}
return temp;
temp = 0x7FFF0000;
set_DSPControl_overflow_flag(1, 21, env);
} else {
- temp = (a * b) << 1;
+ temp = ((int16_t)a * (int16_t)b) << 1;
temp = temp + 0x00008000;
}
resultdsp = 1;
__asm
- ("mulq_rs.ph %0, %2, %3\n\t"
+ ("wrdsp $0\n\t"
+ "mulq_rs.ph %0, %2, %3\n\t"
+ "rddsp %1\n\t"
+ : "=r"(rd), "=r"(dsp)
+ : "r"(rs), "r"(rt)
+ );
+ dsp = (dsp >> 21) & 0x01;
+ assert(rd == result);
+ assert(dsp == resultdsp);
+
+ rs = 0x80011234;
+ rt = 0x80024321;
+ result = 0x7FFD098C;
+ resultdsp = 0;
+
+ __asm
+ ("wrdsp $0\n\t"
+ "mulq_rs.ph %0, %2, %3\n\t"
"rddsp %1\n\t"
: "=r"(rd), "=r"(dsp)
: "r"(rs), "r"(rt)