W90221X Winbond Electronics Corp America, W90221X Datasheet - Page 208

• Manufacturer Part Number: W90221X
• Description: Pa-risc Embedded Controller
• Manufacturer: Winbond Electronics Corp America

zero_ext(GR[r2]{0:15}),
zero_ext(GR[r2]{0:15}),
zero_ext(GR[r2]{0:15}),
}
Exception : None
Halfword Multiply And Subtract
Format:
Purpose: To multiply two sign 16-bit halfword of GR[r1] and GR[r2], then subtract
the multiplied result from {HI, LO} accumulate register.
Description: The corresponding 16-bit halfwords of GR[r1] and GR[r2] are
interpretted as signed operands, and are arithmetically multiplied and subtract the
product from the present contents of the {HI, LO} register, the 64-bit result is placed
in {HI, LO} register, and word result is placed in GR[t]. The bit in AIR[25] which
indicates operates in integer or fraction mode determines the high-order halfword or
low-order halfword of GR[r1], GR[r2] will be as the two operands .
truncated the lower 16 bits when the least 16th bit is zero. IF the the least 16th bit is
one, add one the high-order 16 bits and truncate the low-order 16 bits.
Operation:
Integer mode operation (AIR[25] = 0) :
switch (cmplt) {
W90221X version 0.6
The completer "r" indicates operating in rounding mode, the multiply result can be
default : (r=0, unrounding mode){
05
0:5
6
case r: (r=1, rounding mode){
r2
6:10
{HI, LO}
}
GR[t]{0:31}
{HI, LO}
}
5
break;
break;
HMSB, cmplt
r1
11:15
5
~
16:18
3
1) + 16h8000){0:63};
1)){32:63};
1)){0:63};
r1,r2,t
({HI,
r
({HI, LO} + lshift(zero_ext(GR[r1]{0:15}) *
({HI, LO} + lshift(zero_ext(GR[r1]{0:15}) *
19
1
1
LO}
20
1
05
+
lshift(zero_ext(GR[r1]{0:15})
21:25
~
5
HMSB
t
26
1
27:31
5
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