W90221X Winbond Electronics Corp America, W90221X Datasheet - Page 214

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

zero_ext(GR[r2]{0:31}),
}
Exception : None
Multiply And Subtract
Format:
Purpose: To multiply two sign 32-bit word of GR[r1] and GR[r2], then subtract the
product from accumulate register {HI, LO}.
Description: The corresponding 32-bit word of GR[r1] and GR[r2] are interpretted as
signed 32-bit 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. The bit in AIR[25] indicates operating in integer or fraction mode.
truncated the lower 32 bits when the least 32th bit is zero. IF the the least 32th bit is
one, add one the high-order 32 bits and truncate the low-order 32 bits.
Operation:
Integer mode operation (AIR[25] = 0) :
switch (cmplt) {
sign_ext(GR[r2]{0:31})
sign_ext(GR[r2]{0:31})
sign_ext(GR[r2]{0:31}){32:63};
W90221X version 0.6
The completer "r" indicates operating in rounding mode, the multiply result can be
05
0:5
6
default : (r=0, unrounding mode){
case r : (r=1, rounding mode){
r2
}
6:10
{HI, LO}
break;
5
GR[t]{0:31}
}
MSB, cmplt
GR[t]{0:31}
{HI, LO}
break;
r1
11:1
5
~
16:18
3
1){0:31};
1){0:63};
r1,r2,t
r
+ 32h80000000){0:31};
+ 32h80000000){0:63};
{HI,
({HI,
({HI, LO} + lshift(zero_ext(GR[r1]{0:31}) *
19
1
1
({HI, LO} - (sign_ext(GR[r1]{0:31}) *
LO}
LO}
20
1
15
-
-
21:25
~
5
(sign_ext(GR[r1]{0:31})
sign_ext(GR[r1]{0:31})
t
26
1
27:31
MSB
5
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