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30 lines
748 B
C
30 lines
748 B
C
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// SPDX-License-Identifier: Apache-2.0 OR MIT OR Unlicense
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layout(set = 0, binding = 0) buffer Memory {
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// offset into memory of the next allocation, initialized by the user.
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uint mem_offset;
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bool mem_overflow;
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uint[] memory;
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};
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// Alloc represents a memory allocation.
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struct Alloc {
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// offset in bytes into memory.
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uint offset;
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// failed is true if the allocation overflowed memory.
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bool failed;
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};
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// malloc allocates size bytes of memory.
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Alloc malloc(uint size) {
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Alloc a;
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// Round up to nearest 32-bit word.
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size = (size + 3) & ~3;
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a.offset = atomicAdd(mem_offset, size);
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a.failed = a.offset + size > memory.length() * 4;
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if (a.failed) {
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mem_overflow = true;
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}
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return a;
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}
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