| // Copyright 2019 The Fuchsia Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| // |
| // |
| // |
| |
| #include <stdlib.h> |
| |
| // |
| // |
| // |
| |
| #include "common/macros.h" |
| #include "find_mem_type_idx.h" |
| |
| // |
| // |
| // |
| |
| static uint32_t |
| vk_spn_ffs(uint32_t * lsb, uint32_t const mask) |
| { |
| #ifdef _MSC_VER |
| return _BitScanForward((unsigned long *)lsb, mask); // returns 0 or 1 |
| #else |
| uint32_t const lsb_plus_1 = __builtin_ffs(mask); |
| |
| *lsb = lsb_plus_1 - 1; |
| |
| return lsb_plus_1; // returns [0,32] |
| #endif |
| } |
| |
| // |
| // |
| // |
| |
| uint32_t |
| vk_find_mem_type_idx(VkPhysicalDeviceMemoryProperties const * pdmp, |
| uint32_t memoryTypeBits, |
| VkMemoryPropertyFlags const mpf) |
| { |
| // |
| // FIXME -- jump between indices in the memoryTypeBits mask |
| // |
| uint32_t lsb; |
| |
| while (vk_spn_ffs(&lsb, memoryTypeBits) != 0) |
| { |
| // clear this bit |
| memoryTypeBits ^= (1u << lsb); |
| |
| // otherwise, find first match... |
| VkMemoryPropertyFlags const common = pdmp->memoryTypes[lsb].propertyFlags & mpf; |
| |
| if (common == mpf) |
| { |
| return lsb; |
| } |
| } |
| |
| return UINT32_MAX; |
| } |
| |
| // |
| // |
| // |
