diff options
| author | Mattias Andrée <m@maandree.se> | 2026-01-18 12:06:45 +0100 |
|---|---|---|
| committer | Mattias Andrée <m@maandree.se> | 2026-01-18 12:06:45 +0100 |
| commit | 710922b5bb1a2d34ac919c408be139ee8ea748d2 (patch) | |
| tree | dd37756cc169fc4dde666d97d121392fee638f5e /libj2_j2i_lsh.3 | |
| parent | Fix man pages (diff) | |
| download | libj2-710922b5bb1a2d34ac919c408be139ee8ea748d2.tar.gz libj2-710922b5bb1a2d34ac919c408be139ee8ea748d2.tar.bz2 libj2-710922b5bb1a2d34ac919c408be139ee8ea748d2.tar.xz | |
Add lsh man pages
Signed-off-by: Mattias Andrée <m@maandree.se>
Diffstat (limited to 'libj2_j2i_lsh.3')
| -rw-r--r-- | libj2_j2i_lsh.3 | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/libj2_j2i_lsh.3 b/libj2_j2i_lsh.3 new file mode 100644 index 0000000..70f0577 --- /dev/null +++ b/libj2_j2i_lsh.3 @@ -0,0 +1,118 @@ +.TH LIBJ2_J2I_LSH 3 LIBJ2 +.SH NAME +libj2_j2i_lsh \- Left-shift bits + +.SH SYNOPSIS +.nf +#include <libj2.h> + +void \fBlibj2_j2i_lsh\fP(struct libj2_j2i *\fIa\fP, unsigned \fIb\fP); +void \fBlibj2_j2i_lsh_to_j2i\fP(const struct libj2_j2i *\fIa\fP, unsigned \fIb\fP, struct libj2_j2i *\fIr\fP); +void \fBlibj2_ji_lsh_to_j2i\fP(intmax_t \fIa\fP, unsigned \fIb\fP, struct libj2_j2i *\fIr\fP); +void \fBlibj2_j2u_lsh\fP(struct libj2_j2u *\fIa\fP, unsigned \fIb\fP); +void \fBlibj2_j2u_lsh_to_j2u\fP(const struct libj2_j2u *\fIa\fP, unsigned \fIb\fP, struct libj2_j2u *\fIr\fP); +void \fBlibj2_ju_lsh_to_j2u\fP(uintmax_t \fIa\fP, unsigned \fIb\fP, struct libj2_j2u *\fIr\fP); +int \fBlibj2_j2i_lsh_overflow\fP(struct libj2_j2i *\fIa\fP, unsigned \fIb\fP); +int \fBlibj2_j2i_lsh_to_j2i_overflow\fP(const struct libj2_j2i *\fIa\fP, unsigned \fIb\fP, struct libj2_j2i *\fIr\fP); +int \fBlibj2_ji_lsh_to_j2i_overflow\fP(intmax_t \fIa\fP, unsigned \fIb\fP, struct libj2_j2i *\fIr\fP); +int \fBlibj2_j2u_lsh_overflow\fP(struct libj2_j2u *\fIa\fP, unsigned \fIb\fP); +int \fBlibj2_j2u_lsh_to_j2u_overflow\fP(const struct libj2_j2u *\fIa\fP, unsigned \fIb\fP, struct libj2_j2u *\fIr\fP); +int \fBlibj2_ju_lsh_to_j2u_overflow\fP(uintmax_t \fIa\fP, unsigned \fIb\fP, struct libj2_j2u *\fIr\fP); +int \fBlibj2_j2i_lsh_overflow_p\fP(const struct libj2_j2i *\fIa\fP, unsigned \fIb\fP); +int \fBlibj2_ji_lsh_overflow_p\fP(intmax_t \fIa\fP, unsigned \fIb\fP); +int \fBlibj2_j2u_lsh_overflow_p\fP(const struct libj2_j2u *\fIa\fP, unsigned \fIb\fP); +int \fBlibj2_ju_lsh_overflow_p\fP(uintmax_t \fIa\fP, unsigned \fIb\fP); +.fi +.PP +Link with +.IR -lj2 . + +.SH DESCRIPTION +The above listed functions discard the +.I b +most significant bits in +.IR a , +shift all bits to +.I b +more significant positions, and clears the +.I b +least significant bits, effectively multiplying +.I a +by 2 to the power of +.IR b . +The functions with the parameter +.I r +store the result in +.IR r , +the other functions store the result in +.IR a , +except the functions +.BR libj2_j2i_lsh_overflow_p (), +.BR libj2_ji_lsh_overflow_p (), +.BR libj2_j2u_lsh_overflow_p (), +and +.BR libj2_ju_lsh_overflow_p (), +only predict overflow, and do not perform +any bit-shifting, and therefore does store +it anywhere. +.PP +The value-returning functions (that is, those +with word +.B overflow +in their name), detect overflow, that is, +if any discarded bit (any of the +.I b +most significant bits) was set. +.PP +The result is truncated to the least significant +bits, as many as can be stored, in case of overflow; +that is, modular arithmetics is used. + +.PP +The arguments are assumed to be +.RI non- NULL . + +.SH RETURN VALUE +For functions with a return value, the functions +return +1 if any discarded bit was set and +.I a +was positive, -1 if any discarded bit was set and +.I a +was negative, +and 0 otherwise. + +.SH ERRORS +The above listed functions cannot fail. + +.SH HISTORY +The +.BR libj2_j2u_lsh (), +.BR libj2_j2u_lsh_to_j2u (), +.BR libj2_ju_lsh_to_j2u (), +.BR libj2_j2u_lsh_overflow (), +.BR libj2_j2u_lsh_to_j2u_overflow (), +.BR libj2_ju_lsh_to_j2u_overflow (), +.BR libj2_j2u_lsh_overflow_p (), +and +.BR libj2_ju_lsh_overflow_p () +functions were added in version 1.0 of +.BR libj2 . +.PP +The +.BR libj2_j2i_lsh (), +.BR libj2_j2i_lsh_to_j2i (), +.BR libj2_ji_lsh_to_j2i (), +.BR libj2_j2i_lsh_overflow (), +.BR libj2_j2i_lsh_to_j2i_overflow (), +.BR libj2_ji_lsh_to_j2i_overflow (), +.BR libj2_j2i_lsh_overflow_p (), +and +.BR libj2_ji_lsh_overflow_p () +functions were added in version 1.1 of +.BR libj2 . + +.SH SEE ALSO +.BR libj2 (7), +.BR libj2_j2i_rsh_j2i (3), +.BR libj2_j2i_lrot_j2i (3), +.BR libj2_j2i_rrot_j2i (3) |
