From ed03a58b655f661ef6f9efd8816efe0c8cf07fa0 Mon Sep 17 00:00:00 2001 From: Derrick Stolee Date: Tue, 8 Dec 2020 17:04:08 -0500 Subject: [PATCH] bitmap: implement bitmap_is_subset() The bitmap_is_subset() function checks if the 'self' bitmap contains any bitmaps that are not on in the 'other' bitmap. Up until this patch, it had a declaration, but no implementation or callers. A subsequent patch will want this function, so implement it here. Helped-by: Junio C Hamano Signed-off-by: Derrick Stolee Signed-off-by: Taylor Blau Signed-off-by: Junio C Hamano --- ewah/bitmap.c | 21 +++++++++++++++++++++ ewah/ewok.h | 2 +- 2 files changed, 22 insertions(+), 1 deletion(-) diff --git a/ewah/bitmap.c b/ewah/bitmap.c index b5f6376282..0d31cdc866 100644 --- a/ewah/bitmap.c +++ b/ewah/bitmap.c @@ -195,6 +195,27 @@ int bitmap_equals(struct bitmap *self, struct bitmap *other) return 1; } +int bitmap_is_subset(struct bitmap *self, struct bitmap *other) +{ + size_t common_size, i; + + if (self->word_alloc < other->word_alloc) + common_size = self->word_alloc; + else { + common_size = other->word_alloc; + for (i = common_size; i < self->word_alloc; i++) { + if (self->words[i]) + return 1; + } + } + + for (i = 0; i < common_size; i++) { + if (self->words[i] & ~other->words[i]) + return 1; + } + return 0; +} + void bitmap_reset(struct bitmap *bitmap) { memset(bitmap->words, 0x0, bitmap->word_alloc * sizeof(eword_t)); diff --git a/ewah/ewok.h b/ewah/ewok.h index 1fc555e672..66920965da 100644 --- a/ewah/ewok.h +++ b/ewah/ewok.h @@ -180,7 +180,7 @@ int bitmap_get(struct bitmap *self, size_t pos); void bitmap_reset(struct bitmap *self); void bitmap_free(struct bitmap *self); int bitmap_equals(struct bitmap *self, struct bitmap *other); -int bitmap_is_subset(struct bitmap *self, struct bitmap *super); +int bitmap_is_subset(struct bitmap *self, struct bitmap *other); struct ewah_bitmap * bitmap_to_ewah(struct bitmap *bitmap); struct bitmap *ewah_to_bitmap(struct ewah_bitmap *ewah);