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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
uint2 tint_first_trailing_bit(uint2 v) {
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uint2 x = uint2(v);
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const uint2 b16 = (bool2((x & uint2((65535u).xx))) ? uint2((0u).xx) : uint2((16u).xx));
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x = (x >> b16);
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const uint2 b8 = (bool2((x & uint2((255u).xx))) ? uint2((0u).xx) : uint2((8u).xx));
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x = (x >> b8);
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const uint2 b4 = (bool2((x & uint2((15u).xx))) ? uint2((0u).xx) : uint2((4u).xx));
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x = (x >> b4);
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const uint2 b2 = (bool2((x & uint2((3u).xx))) ? uint2((0u).xx) : uint2((2u).xx));
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x = (x >> b2);
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const uint2 b1 = (bool2((x & uint2((1u).xx))) ? uint2((0u).xx) : uint2((1u).xx));
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const uint2 is_zero = ((x == uint2((0u).xx)) ? uint2((4294967295u).xx) : uint2((0u).xx));
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return uint2((((((b16 | b8) | b4) | b2) | b1) | is_zero));
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}
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void firstTrailingBit_45eb10() {
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uint2 res = tint_first_trailing_bit(uint2(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_45eb10();
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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_45eb10();
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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_45eb10();
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return;
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}
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