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Diffstat (limited to 'unix/as.mc68020/ishift.s')
| -rw-r--r-- | unix/as.mc68020/ishift.s | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/unix/as.mc68020/ishift.s b/unix/as.mc68020/ishift.s new file mode 100644 index 00000000..cfd6d7e9 --- /dev/null +++ b/unix/as.mc68020/ishift.s @@ -0,0 +1,44 @@ +|# IAND, IOR, ISHIFT -- Bitwise boolean integer functions for the NCAR +|# package. The shift function must rotate the bits left and around +|# if the nbits to shift argument is positive, and zero fill at the left +|# if the shift is negative (right shift). +|# +|# (SUN/UNIX MC68xxx version) + +|# AND -- Bitwise boolean AND: C = AND (A, B) + .text + .globl _iand_ +_iand_: + movl sp@(4),a0 + movl a0@,d0 + movl sp@(8),a0 + andl a0@,d0 + rts + + +|# OR -- Bitwise boolean OR: C = OR (A, B) + .text + .globl _ior_ +_ior_: + movl sp@(4),a0 + movl a0@,d0 + movl sp@(8),a0 + orl a0@,d0 + rts + + +|# ISHIFT -- Bitwise shift: C = ISHIFT (A, NBITS), +=left + .text + .globl _ishift_ +_ishift_: + movl sp@(4),a0 + movl a0@,d0 + movl sp@(8),a0 + movl a0@,d1 + blt L1 + roll d1,d0 |# left rotate (high bits come in at right) + rts +L1: + negl d1 + lsrl d1,d0 |# logical shift right (zero at left) + rts |