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inline bitmap_mask

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daan 2019-11-12 10:17:39 -08:00
parent ef179a6377
commit af746ca4c1
1 changed files with 8 additions and 8 deletions
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16
src/bitmap.inc.c
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@ -8,11 +8,11 @@ terms of the MIT license. A copy of the license can be found in the file
/* ----------------------------------------------------------------------------
This file is meant to be included in other files for efficiency.
It implements a bitmap that can set/reset sequences of bits atomically
and is used to concurrently claim memory ranges.
and is used to concurrently claim memory ranges.
A bitmap is an array of fields where each field is a machine word (`uintptr_t`)
A current limitation is that the bit sequences cannot cross fields
A current limitation is that the bit sequences cannot cross fields
and that the sequence must be smaller or equal to the bits in a field.
---------------------------------------------------------------------------- */
#pragma once
@ -59,7 +59,7 @@ static inline size_t mi_bitmap_index_bit(mi_bitmap_index_t bitmap_idx) {
// The bit mask for a given number of blocks at a specified bit index.
static uintptr_t mi_bitmap_mask_(size_t count, size_t bitidx) {
static inline uintptr_t mi_bitmap_mask_(size_t count, size_t bitidx) {
mi_assert_internal(count + bitidx <= MI_BITMAP_FIELD_BITS);
if (count == MI_BITMAP_FIELD_BITS) return MI_BITMAP_FIELD_FULL;
return ((((uintptr_t)1 << count) - 1) << bitidx);
@ -104,10 +104,10 @@ static inline size_t mi_bsr(uintptr_t x) {
Claim a bit sequence atomically
----------------------------------------------------------- */
// Try to atomically claim a sequence of `count` bits in a single
// Try to atomically claim a sequence of `count` bits in a single
// field at `idx` in `bitmap`. Returns `true` on success.
static inline bool mi_bitmap_try_claim_field(mi_bitmap_t bitmap, size_t idx, const size_t count, mi_bitmap_index_t* bitmap_idx)
{
static inline bool mi_bitmap_try_claim_field(mi_bitmap_t bitmap, size_t idx, const size_t count, mi_bitmap_index_t* bitmap_idx)
{
mi_assert_internal(bitmap_idx != NULL);
volatile _Atomic(uintptr_t)* field = &bitmap[idx];
uintptr_t map = mi_atomic_read(field);
@ -136,7 +136,7 @@ static inline bool mi_bitmap_try_claim_field(mi_bitmap_t bitmap, size_t idx, con
continue;
}
else {
// success, we claimed the bits!
// success, we claimed the bits!
*bitmap_idx = mi_bitmap_index_create(idx, bitidx);
return true;
}
@ -205,4 +205,4 @@ static inline bool mi_bitmap_is_claimed(mi_bitmap_t bitmap, size_t bitmap_fields
return ((mi_atomic_read(&bitmap[idx]) & mask) == mask);
}
#endif
#endif