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https://github.com/encounter/dawn-cmake.git
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df3630c194
Currently polyfilled for all backends. HLSL should be able to map this to 'firstbitlow', but there might need to be some special case handling for 0 (undocumented behavior). For now just polyfill. CTS tests: https://github.com/gpuweb/cts/pull/1003 Bug: tint:1367 Bug: tint:1449 Change-Id: I8125b32687196678906e5a9d056b4f2efd885073 Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/81502 Kokoro: Kokoro <noreply+kokoro@google.com> Reviewed-by: David Neto <dneto@google.com> Commit-Queue: Ben Clayton <bclayton@google.com>
46 lines
1.3 KiB
HLSL
46 lines
1.3 KiB
HLSL
uint3 tint_first_trailing_bit(uint3 v) {
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uint3 x = uint3(v);
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const uint3 b16 = (bool3((x & uint3((65535u).xxx))) ? uint3((0u).xxx) : uint3((16u).xxx));
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x = (x >> b16);
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const uint3 b8 = (bool3((x & uint3((255u).xxx))) ? uint3((0u).xxx) : uint3((8u).xxx));
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x = (x >> b8);
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const uint3 b4 = (bool3((x & uint3((15u).xxx))) ? uint3((0u).xxx) : uint3((4u).xxx));
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x = (x >> b4);
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const uint3 b2 = (bool3((x & uint3((3u).xxx))) ? uint3((0u).xxx) : uint3((2u).xxx));
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x = (x >> b2);
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const uint3 b1 = (bool3((x & uint3((1u).xxx))) ? uint3((0u).xxx) : uint3((1u).xxx));
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const uint3 is_zero = ((x == uint3((0u).xxx)) ? uint3((4294967295u).xxx) : uint3((0u).xxx));
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return uint3((((((b16 | b8) | b4) | b2) | b1) | is_zero));
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}
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void firstTrailingBit_cb51ce() {
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uint3 res = tint_first_trailing_bit(uint3(0u, 0u, 0u));
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}
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struct tint_symbol {
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float4 value : SV_Position;
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};
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float4 vertex_main_inner() {
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firstTrailingBit_cb51ce();
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return float4(0.0f, 0.0f, 0.0f, 0.0f);
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}
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tint_symbol vertex_main() {
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const float4 inner_result = vertex_main_inner();
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tint_symbol wrapper_result = (tint_symbol)0;
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wrapper_result.value = inner_result;
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return wrapper_result;
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}
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void fragment_main() {
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firstTrailingBit_cb51ce();
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return;
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}
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[numthreads(1, 1, 1)]
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void compute_main() {
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firstTrailingBit_cb51ce();
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return;
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}
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