Intel i86W Manual page 207

INSTRUCTION SET SUMMARY
pfzchks
fsrcl, fsrc2, fdes! .................................................... Pipelined 16-Bit Z-Buffer Check
Consider fsrcl, fsrc2, and fdes! as arrays of four 16-bit
fields fsrcl (O).!srcl (3), fsrc2 (0).!src2 (3), and fdest (0).!dest(3)
where zero denotes the least-significant field.
PM
~
PM shifted right by 4 bits
FOR i
=
0 to 3
DO
PM [i
+
4]
~
fsrc2(i)
~
fsrcl(i) (unsigned)
fdest
~
last stage graphics result
last stage graphics result(i)
~
smaller of fsrc2 (i) and fsrcl (i)
aD
MERGE ~ 0
Pixel Store
pst.d
fdest, #cons!(isrc2) .......................................................................................... {Normal)
pst.d
fdest, #cons!(isrc2)
+ + .......................................................................
{Autoincrement)
Pixels enabled by PM in mem.d (isrc2
+
#const)
~
fdest
Shift PM right by 8/pixel size (in bytes) bits
IF autoincrement
THEN isrc2 ~
#const
+
isrc2
FI
shl
isrcl, isrc2, idest ................................................................................................... Shift Left
ides!
~ isrc2 shifted left by isrcl bits
shr
isrcl, isrc2, idest ................................................................................................ Shift Right
SC (in
psr)
~
isrcl
idest~
isrc2 shifted right by isrcl bits
shra isrcl, isrc2, ides! ........................................................................... Shift Right Arithmetic
idest
~
isrc2 arithmetically shifted right by isrcl bits
shrd
isrclni, isrc2, idest .............................................................................. Shift Right Double
ides!
~
low-order 32 bits of isrclni:isrc2 shifted right by SC bits
st.c
srclni, csrc2 .............................................................................. Store to Control Register
csrc2
~
srclni
st.x
isrclni, #const (isrc2) .................................................................................... Store Integer
mem.x (isrc2
+
#const)
~
isrclni
subs isrcl, isrc2, ides! ..................................................................................... Subtract Signed
ides!
~
isrcl - isrc2
OF
~
(bit 31 carry
~
bit 30 carry)
CC set if isrc2 > isrcl (signed)
CC clear if isrc2
~
isrcl (signed)
A-11