| Message ID | 20230803162245.302488-1-cgzones@googlemail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 8b0acb05351e |
| Delegated to: | Petr Lautrbach |
| Headers | show |
| Series | libsepol: ebitmap: avoid branches for iteration | expand |
On Thu, Aug 3, 2023 at 12:36 PM Christian Göttsche <cgzones@googlemail.com> wrote: > > Otherwise Linus might think we don't understand pointers. > > Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Acked-by: James Carter <jwcart2@gmail.com> > --- > libsepol/src/ebitmap.c | 83 +++++++++++++++++++----------------------- > 1 file changed, 37 insertions(+), 46 deletions(-) > > diff --git a/libsepol/src/ebitmap.c b/libsepol/src/ebitmap.c > index 3ec1042f..f166b7d6 100644 > --- a/libsepol/src/ebitmap.c > +++ b/libsepol/src/ebitmap.c > @@ -18,13 +18,13 @@ > int ebitmap_or(ebitmap_t * dst, const ebitmap_t * e1, const ebitmap_t * e2) > { > const ebitmap_node_t *n1, *n2; > - ebitmap_node_t *new, *prev; > + ebitmap_node_t *new = NULL, **prev; > > ebitmap_init(dst); > > + prev = &dst->node; > n1 = e1->node; > n2 = e2->node; > - prev = 0; > while (n1 || n2) { > new = (ebitmap_node_t *) malloc(sizeof(ebitmap_node_t)); > if (!new) { > @@ -46,12 +46,10 @@ int ebitmap_or(ebitmap_t * dst, const ebitmap_t * e1, const ebitmap_t * e2) > n2 = n2->next; > } > > - new->next = 0; > - if (prev) > - prev->next = new; > - else > - dst->node = new; > - prev = new; > + new->next = NULL; > + > + *prev = new; > + prev = &new->next; > } > > dst->highbit = (e1->highbit > e2->highbit) ? e1->highbit : e2->highbit; > @@ -74,10 +72,11 @@ int ebitmap_union(ebitmap_t * dst, const ebitmap_t * e1) > int ebitmap_and(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) > { > const ebitmap_node_t *n1, *n2; > - ebitmap_node_t *new, *prev = NULL; > + ebitmap_node_t *new = NULL, **prev; > > ebitmap_init(dst); > > + prev = &dst->node; > n1 = e1->node; > n2 = e2->node; > while (n1 && n2) { > @@ -92,11 +91,8 @@ int ebitmap_and(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) > new->map = n1->map & n2->map; > new->next = NULL; > > - if (prev) > - prev->next = new; > - else > - dst->node = new; > - prev = new; > + *prev = new; > + prev = &new->next; > } > > n1 = n1->next; > @@ -108,8 +104,8 @@ int ebitmap_and(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) > } > } > > - if (prev) > - dst->highbit = prev->startbit + MAPSIZE; > + if (new) > + dst->highbit = new->startbit + MAPSIZE; > > return 0; > } > @@ -117,12 +113,13 @@ int ebitmap_and(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) > int ebitmap_xor(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) > { > const ebitmap_node_t *n1, *n2; > - ebitmap_node_t *new, *prev = NULL; > + ebitmap_node_t *new = NULL, **prev; > uint32_t startbit; > MAPTYPE map; > > ebitmap_init(dst); > > + prev = &dst->node; > n1 = e1->node; > n2 = e2->node; > while (n1 || n2) { > @@ -150,16 +147,14 @@ int ebitmap_xor(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) > new->startbit = startbit; > new->map = map; > new->next = NULL; > - if (prev) > - prev->next = new; > - else > - dst->node = new; > - prev = new; > + > + *prev = new; > + prev = &new->next; > } > } > > - if (prev) > - dst->highbit = prev->startbit + MAPSIZE; > + if (new) > + dst->highbit = new->startbit + MAPSIZE; > > return 0; > } > @@ -167,12 +162,13 @@ int ebitmap_xor(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) > int ebitmap_not(ebitmap_t *dst, const ebitmap_t *e1, unsigned int maxbit) > { > const ebitmap_node_t *n; > - ebitmap_node_t *new, *prev = NULL; > + ebitmap_node_t *new = NULL, **prev; > uint32_t startbit, cur_startbit; > MAPTYPE map; > > ebitmap_init(dst); > > + prev = &dst->node; > n = e1->node; > for (cur_startbit = 0; cur_startbit < maxbit; cur_startbit += MAPSIZE) { > if (n && n->startbit == cur_startbit) { > @@ -199,16 +195,13 @@ int ebitmap_not(ebitmap_t *dst, const ebitmap_t *e1, unsigned int maxbit) > new->map = map; > new->next = NULL; > > - if (prev) > - prev->next = new; > - else > - dst->node = new; > - prev = new; > + *prev = new; > + prev = &new->next; > } > } > > - if (prev) > - dst->highbit = prev->startbit + MAPSIZE; > + if (new) > + dst->highbit = new->startbit + MAPSIZE; > > return 0; > } > @@ -278,11 +271,11 @@ int ebitmap_cmp(const ebitmap_t * e1, const ebitmap_t * e2) > int ebitmap_cpy(ebitmap_t * dst, const ebitmap_t * src) > { > const ebitmap_node_t *n; > - ebitmap_node_t *new, *prev; > + ebitmap_node_t *new = NULL, **prev; > > ebitmap_init(dst); > n = src->node; > - prev = 0; > + prev = &dst->node; > while (n) { > new = (ebitmap_node_t *) malloc(sizeof(ebitmap_node_t)); > if (!new) { > @@ -291,12 +284,11 @@ int ebitmap_cpy(ebitmap_t * dst, const ebitmap_t * src) > } > new->startbit = n->startbit; > new->map = n->map; > - new->next = 0; > - if (prev) > - prev->next = new; > - else > - dst->node = new; > - prev = new; > + new->next = NULL; > + > + *prev = new; > + prev = &new->next; > + > n = n->next; > } > > @@ -450,7 +442,7 @@ int ebitmap_set_bit(ebitmap_t * e, unsigned int bit, int value) > > int ebitmap_init_range(ebitmap_t * e, unsigned int minbit, unsigned int maxbit) > { > - ebitmap_node_t *new, *prev = NULL; > + ebitmap_node_t *new = NULL, **prev; > uint32_t minstartbit = minbit & ~(MAPSIZE - 1); > uint32_t maxstartbit = maxbit & ~(MAPSIZE - 1); > uint32_t minhighbit = minstartbit + MAPSIZE; > @@ -466,6 +458,8 @@ int ebitmap_init_range(ebitmap_t * e, unsigned int minbit, unsigned int maxbit) > if (minhighbit == 0 || maxhighbit == 0) > return -EOVERFLOW; > > + prev = &e->node; > + > for (startbit = minstartbit; startbit <= maxstartbit; startbit += MAPSIZE) { > new = malloc(sizeof(ebitmap_node_t)); > if (!new) > @@ -485,11 +479,8 @@ int ebitmap_init_range(ebitmap_t * e, unsigned int minbit, unsigned int maxbit) > new->map = (mask << (minbit - startbit)); > } > > - if (prev) > - prev->next = new; > - else > - e->node = new; > - prev = new; > + *prev = new; > + prev = &new->next; > } > > e->highbit = maxhighbit; > -- > 2.40.1 >
On Tue, Aug 8, 2023 at 2:20 PM James Carter <jwcart2@gmail.com> wrote: > > On Thu, Aug 3, 2023 at 12:36 PM Christian Göttsche > <cgzones@googlemail.com> wrote: > > > > Otherwise Linus might think we don't understand pointers. > > > > Signed-off-by: Christian Göttsche <cgzones@googlemail.com> > > Acked-by: James Carter <jwcart2@gmail.com> > Merged. Thanks, Jim > > --- > > libsepol/src/ebitmap.c | 83 +++++++++++++++++++----------------------- > > 1 file changed, 37 insertions(+), 46 deletions(-) > > > > diff --git a/libsepol/src/ebitmap.c b/libsepol/src/ebitmap.c > > index 3ec1042f..f166b7d6 100644 > > --- a/libsepol/src/ebitmap.c > > +++ b/libsepol/src/ebitmap.c > > @@ -18,13 +18,13 @@ > > int ebitmap_or(ebitmap_t * dst, const ebitmap_t * e1, const ebitmap_t * e2) > > { > > const ebitmap_node_t *n1, *n2; > > - ebitmap_node_t *new, *prev; > > + ebitmap_node_t *new = NULL, **prev; > > > > ebitmap_init(dst); > > > > + prev = &dst->node; > > n1 = e1->node; > > n2 = e2->node; > > - prev = 0; > > while (n1 || n2) { > > new = (ebitmap_node_t *) malloc(sizeof(ebitmap_node_t)); > > if (!new) { > > @@ -46,12 +46,10 @@ int ebitmap_or(ebitmap_t * dst, const ebitmap_t * e1, const ebitmap_t * e2) > > n2 = n2->next; > > } > > > > - new->next = 0; > > - if (prev) > > - prev->next = new; > > - else > > - dst->node = new; > > - prev = new; > > + new->next = NULL; > > + > > + *prev = new; > > + prev = &new->next; > > } > > > > dst->highbit = (e1->highbit > e2->highbit) ? e1->highbit : e2->highbit; > > @@ -74,10 +72,11 @@ int ebitmap_union(ebitmap_t * dst, const ebitmap_t * e1) > > int ebitmap_and(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) > > { > > const ebitmap_node_t *n1, *n2; > > - ebitmap_node_t *new, *prev = NULL; > > + ebitmap_node_t *new = NULL, **prev; > > > > ebitmap_init(dst); > > > > + prev = &dst->node; > > n1 = e1->node; > > n2 = e2->node; > > while (n1 && n2) { > > @@ -92,11 +91,8 @@ int ebitmap_and(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) > > new->map = n1->map & n2->map; > > new->next = NULL; > > > > - if (prev) > > - prev->next = new; > > - else > > - dst->node = new; > > - prev = new; > > + *prev = new; > > + prev = &new->next; > > } > > > > n1 = n1->next; > > @@ -108,8 +104,8 @@ int ebitmap_and(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) > > } > > } > > > > - if (prev) > > - dst->highbit = prev->startbit + MAPSIZE; > > + if (new) > > + dst->highbit = new->startbit + MAPSIZE; > > > > return 0; > > } > > @@ -117,12 +113,13 @@ int ebitmap_and(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) > > int ebitmap_xor(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) > > { > > const ebitmap_node_t *n1, *n2; > > - ebitmap_node_t *new, *prev = NULL; > > + ebitmap_node_t *new = NULL, **prev; > > uint32_t startbit; > > MAPTYPE map; > > > > ebitmap_init(dst); > > > > + prev = &dst->node; > > n1 = e1->node; > > n2 = e2->node; > > while (n1 || n2) { > > @@ -150,16 +147,14 @@ int ebitmap_xor(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) > > new->startbit = startbit; > > new->map = map; > > new->next = NULL; > > - if (prev) > > - prev->next = new; > > - else > > - dst->node = new; > > - prev = new; > > + > > + *prev = new; > > + prev = &new->next; > > } > > } > > > > - if (prev) > > - dst->highbit = prev->startbit + MAPSIZE; > > + if (new) > > + dst->highbit = new->startbit + MAPSIZE; > > > > return 0; > > } > > @@ -167,12 +162,13 @@ int ebitmap_xor(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) > > int ebitmap_not(ebitmap_t *dst, const ebitmap_t *e1, unsigned int maxbit) > > { > > const ebitmap_node_t *n; > > - ebitmap_node_t *new, *prev = NULL; > > + ebitmap_node_t *new = NULL, **prev; > > uint32_t startbit, cur_startbit; > > MAPTYPE map; > > > > ebitmap_init(dst); > > > > + prev = &dst->node; > > n = e1->node; > > for (cur_startbit = 0; cur_startbit < maxbit; cur_startbit += MAPSIZE) { > > if (n && n->startbit == cur_startbit) { > > @@ -199,16 +195,13 @@ int ebitmap_not(ebitmap_t *dst, const ebitmap_t *e1, unsigned int maxbit) > > new->map = map; > > new->next = NULL; > > > > - if (prev) > > - prev->next = new; > > - else > > - dst->node = new; > > - prev = new; > > + *prev = new; > > + prev = &new->next; > > } > > } > > > > - if (prev) > > - dst->highbit = prev->startbit + MAPSIZE; > > + if (new) > > + dst->highbit = new->startbit + MAPSIZE; > > > > return 0; > > } > > @@ -278,11 +271,11 @@ int ebitmap_cmp(const ebitmap_t * e1, const ebitmap_t * e2) > > int ebitmap_cpy(ebitmap_t * dst, const ebitmap_t * src) > > { > > const ebitmap_node_t *n; > > - ebitmap_node_t *new, *prev; > > + ebitmap_node_t *new = NULL, **prev; > > > > ebitmap_init(dst); > > n = src->node; > > - prev = 0; > > + prev = &dst->node; > > while (n) { > > new = (ebitmap_node_t *) malloc(sizeof(ebitmap_node_t)); > > if (!new) { > > @@ -291,12 +284,11 @@ int ebitmap_cpy(ebitmap_t * dst, const ebitmap_t * src) > > } > > new->startbit = n->startbit; > > new->map = n->map; > > - new->next = 0; > > - if (prev) > > - prev->next = new; > > - else > > - dst->node = new; > > - prev = new; > > + new->next = NULL; > > + > > + *prev = new; > > + prev = &new->next; > > + > > n = n->next; > > } > > > > @@ -450,7 +442,7 @@ int ebitmap_set_bit(ebitmap_t * e, unsigned int bit, int value) > > > > int ebitmap_init_range(ebitmap_t * e, unsigned int minbit, unsigned int maxbit) > > { > > - ebitmap_node_t *new, *prev = NULL; > > + ebitmap_node_t *new = NULL, **prev; > > uint32_t minstartbit = minbit & ~(MAPSIZE - 1); > > uint32_t maxstartbit = maxbit & ~(MAPSIZE - 1); > > uint32_t minhighbit = minstartbit + MAPSIZE; > > @@ -466,6 +458,8 @@ int ebitmap_init_range(ebitmap_t * e, unsigned int minbit, unsigned int maxbit) > > if (minhighbit == 0 || maxhighbit == 0) > > return -EOVERFLOW; > > > > + prev = &e->node; > > + > > for (startbit = minstartbit; startbit <= maxstartbit; startbit += MAPSIZE) { > > new = malloc(sizeof(ebitmap_node_t)); > > if (!new) > > @@ -485,11 +479,8 @@ int ebitmap_init_range(ebitmap_t * e, unsigned int minbit, unsigned int maxbit) > > new->map = (mask << (minbit - startbit)); > > } > > > > - if (prev) > > - prev->next = new; > > - else > > - e->node = new; > > - prev = new; > > + *prev = new; > > + prev = &new->next; > > } > > > > e->highbit = maxhighbit; > > -- > > 2.40.1 > >
diff --git a/libsepol/src/ebitmap.c b/libsepol/src/ebitmap.c index 3ec1042f..f166b7d6 100644 --- a/libsepol/src/ebitmap.c +++ b/libsepol/src/ebitmap.c @@ -18,13 +18,13 @@ int ebitmap_or(ebitmap_t * dst, const ebitmap_t * e1, const ebitmap_t * e2) { const ebitmap_node_t *n1, *n2; - ebitmap_node_t *new, *prev; + ebitmap_node_t *new = NULL, **prev; ebitmap_init(dst); + prev = &dst->node; n1 = e1->node; n2 = e2->node; - prev = 0; while (n1 || n2) { new = (ebitmap_node_t *) malloc(sizeof(ebitmap_node_t)); if (!new) { @@ -46,12 +46,10 @@ int ebitmap_or(ebitmap_t * dst, const ebitmap_t * e1, const ebitmap_t * e2) n2 = n2->next; } - new->next = 0; - if (prev) - prev->next = new; - else - dst->node = new; - prev = new; + new->next = NULL; + + *prev = new; + prev = &new->next; } dst->highbit = (e1->highbit > e2->highbit) ? e1->highbit : e2->highbit; @@ -74,10 +72,11 @@ int ebitmap_union(ebitmap_t * dst, const ebitmap_t * e1) int ebitmap_and(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) { const ebitmap_node_t *n1, *n2; - ebitmap_node_t *new, *prev = NULL; + ebitmap_node_t *new = NULL, **prev; ebitmap_init(dst); + prev = &dst->node; n1 = e1->node; n2 = e2->node; while (n1 && n2) { @@ -92,11 +91,8 @@ int ebitmap_and(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) new->map = n1->map & n2->map; new->next = NULL; - if (prev) - prev->next = new; - else - dst->node = new; - prev = new; + *prev = new; + prev = &new->next; } n1 = n1->next; @@ -108,8 +104,8 @@ int ebitmap_and(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) } } - if (prev) - dst->highbit = prev->startbit + MAPSIZE; + if (new) + dst->highbit = new->startbit + MAPSIZE; return 0; } @@ -117,12 +113,13 @@ int ebitmap_and(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) int ebitmap_xor(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) { const ebitmap_node_t *n1, *n2; - ebitmap_node_t *new, *prev = NULL; + ebitmap_node_t *new = NULL, **prev; uint32_t startbit; MAPTYPE map; ebitmap_init(dst); + prev = &dst->node; n1 = e1->node; n2 = e2->node; while (n1 || n2) { @@ -150,16 +147,14 @@ int ebitmap_xor(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) new->startbit = startbit; new->map = map; new->next = NULL; - if (prev) - prev->next = new; - else - dst->node = new; - prev = new; + + *prev = new; + prev = &new->next; } } - if (prev) - dst->highbit = prev->startbit + MAPSIZE; + if (new) + dst->highbit = new->startbit + MAPSIZE; return 0; } @@ -167,12 +162,13 @@ int ebitmap_xor(ebitmap_t *dst, const ebitmap_t *e1, const ebitmap_t *e2) int ebitmap_not(ebitmap_t *dst, const ebitmap_t *e1, unsigned int maxbit) { const ebitmap_node_t *n; - ebitmap_node_t *new, *prev = NULL; + ebitmap_node_t *new = NULL, **prev; uint32_t startbit, cur_startbit; MAPTYPE map; ebitmap_init(dst); + prev = &dst->node; n = e1->node; for (cur_startbit = 0; cur_startbit < maxbit; cur_startbit += MAPSIZE) { if (n && n->startbit == cur_startbit) { @@ -199,16 +195,13 @@ int ebitmap_not(ebitmap_t *dst, const ebitmap_t *e1, unsigned int maxbit) new->map = map; new->next = NULL; - if (prev) - prev->next = new; - else - dst->node = new; - prev = new; + *prev = new; + prev = &new->next; } } - if (prev) - dst->highbit = prev->startbit + MAPSIZE; + if (new) + dst->highbit = new->startbit + MAPSIZE; return 0; } @@ -278,11 +271,11 @@ int ebitmap_cmp(const ebitmap_t * e1, const ebitmap_t * e2) int ebitmap_cpy(ebitmap_t * dst, const ebitmap_t * src) { const ebitmap_node_t *n; - ebitmap_node_t *new, *prev; + ebitmap_node_t *new = NULL, **prev; ebitmap_init(dst); n = src->node; - prev = 0; + prev = &dst->node; while (n) { new = (ebitmap_node_t *) malloc(sizeof(ebitmap_node_t)); if (!new) { @@ -291,12 +284,11 @@ int ebitmap_cpy(ebitmap_t * dst, const ebitmap_t * src) } new->startbit = n->startbit; new->map = n->map; - new->next = 0; - if (prev) - prev->next = new; - else - dst->node = new; - prev = new; + new->next = NULL; + + *prev = new; + prev = &new->next; + n = n->next; } @@ -450,7 +442,7 @@ int ebitmap_set_bit(ebitmap_t * e, unsigned int bit, int value) int ebitmap_init_range(ebitmap_t * e, unsigned int minbit, unsigned int maxbit) { - ebitmap_node_t *new, *prev = NULL; + ebitmap_node_t *new = NULL, **prev; uint32_t minstartbit = minbit & ~(MAPSIZE - 1); uint32_t maxstartbit = maxbit & ~(MAPSIZE - 1); uint32_t minhighbit = minstartbit + MAPSIZE; @@ -466,6 +458,8 @@ int ebitmap_init_range(ebitmap_t * e, unsigned int minbit, unsigned int maxbit) if (minhighbit == 0 || maxhighbit == 0) return -EOVERFLOW; + prev = &e->node; + for (startbit = minstartbit; startbit <= maxstartbit; startbit += MAPSIZE) { new = malloc(sizeof(ebitmap_node_t)); if (!new) @@ -485,11 +479,8 @@ int ebitmap_init_range(ebitmap_t * e, unsigned int minbit, unsigned int maxbit) new->map = (mask << (minbit - startbit)); } - if (prev) - prev->next = new; - else - e->node = new; - prev = new; + *prev = new; + prev = &new->next; } e->highbit = maxhighbit;
Otherwise Linus might think we don't understand pointers. Signed-off-by: Christian Göttsche <cgzones@googlemail.com> --- libsepol/src/ebitmap.c | 83 +++++++++++++++++++----------------------- 1 file changed, 37 insertions(+), 46 deletions(-)