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Add macros for rotates.

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Stephen Heumann 2017-06-29 20:41:49 -05:00
parent ad4e0a0dd5
commit dfdb3186fd
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* Right-rotate 32-bit value in &loc (DP or 16-bit address) by &n positions
macro
ROTR4 &loc,&n
aif &n>16,.dorotl
lda &loc+2
lcla &i
&i seta &n
.rotrloop
lsr a ;to set carry
ror &loc
ror &loc+2
&i seta &i-1
aif &i>0,.rotrloop
ago .end
.dorotl
ROTL4 &loc,32-&n
.end
mend
* Left-rotate 32-bit value in &loc (DP or 16-bit address) by &n positions
macro
ROTL4 &loc,&n
aif &n>16,.dorotr
lda &loc
lcla &i
&i seta &n
.rotlloop
asl a ;to set carry
rol &loc+2
rol &loc
&i seta &i-1
aif &i>0,.rotlloop
ago .end
.dorotr
ROTR4 &loc,32-&n
.end
mend
* &to := &from ROTR4 &n
macro
ROTR4MOVE &to,&from,&n
aif &n>16,.dorotl
lda &from
sta &to
lda &from+2
sta &to+2
lcla &i
&i seta &n
.rotrloop
lsr a ;to set carry
ror &to
ror &to+2
&i seta &i-1
aif &i>0,.rotrloop
ago .end
dorotl
ROTL4MOVE &to,&from,32-&n
.end
mend
* &to := &from ROTL4 &n
macro
ROTL4MOVE &to,&from,&n
aif &n>16,.dorotr
lda &from+2
sta &to+2
lda &from
sta &to
lcla &i
&i seta &n
.rotlloop
asl a ;to set carry
rol &to+2
rol &to
&i seta &i-1
aif &i>0,.rotlloop
ago .end
.dorotr
ROTR4MOVE &to,&from,32-&n
.end
mend