Add WaveGetLaneCount tests - #1541
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| [numthreads(1, 1, 1)] | ||
| void main() { | ||
| uint LaneCount = WaveGetLaneCount(); | ||
| Out[0] = LaneCount >= 4 && LaneCount <= 128 ? 1 : 0; |
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| Out[0] = LaneCount >= 4 && LaneCount <= 128 ? 1 : 0; | |
| Out[0] = LaneCount >= 4 && LaneCount <= 128 && countbits(LaneCount) == 1 ? 1 : 0; |
We could be a bit extra here, and also use countbits to make sure this is a power of two (also required).
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take or leave my suggestion
spall
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| # XFAIL: Clang && Vulkan | ||
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| # RUN: split-file %s %t | ||
| # RUN: %dxc_target -T cs_6_5 -Fo %t.o %t/source.hlsl |
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this is supported from sm 6.0 and later; is there a reason you chose to use 6.5?
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No particular reason, maybe because some of the other offload tests are 6.5 / copy paste.
Dropped it to 6.0.
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This PR adds offload tests for the WaveGetLaneCount builtin function.
There is currently a clang-vk failure, but since the rest of it was already implemented, we test for all other targets.
Also I thought about checking for powers of 2, but even if the DirectX / Vulkan backends specify wave size will always be a power of 2, the HLSL doc says we must expect 4 <= return <= 128.
For the unknown backend that has a non-power-of-two wave size, we leave that check off of this test.
Fixes #898
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