Bug 109249

Summary:	vkd3d test failures related to ordered/unordered comparisons in test_shader_instructions()
Product:	Mesa	Reporter:	Józef Kucia <joseph.kucia>
Component:	Drivers/Vulkan/Common	Assignee:	mesa-dev
Status:	RESOLVED MOVED	QA Contact:
Severity:	normal
Priority:	medium	CC:	airlied, chadversary, daniel, idr, jason, samuel.pitoiset
Version:	git
Hardware:	All
OS:	All
Whiteboard:
i915 platform:		i915 features:

Description Józef Kucia 2019-01-08 17:12:35 UTC

Radv and Anv are affected. Nir optimizations appear to flip ordered/unordered comparisons. Removing ~inot optimization from https://gitlab.freedesktop.org/mesa/mesa/blob/add5a2ec92f4b3f7ac8353e5986dc04186a7b6da/src/compiler/nir/nir_opt_algebraic.py#L160 fixes the vkd3d test failures.

See https://lists.freedesktop.org/archives/mesa-dev/2018-December/210780.html for a related discussion.

The problem produces the following test failures on Anv:

d3d12:8258:31:if_return: Test failed: Got {0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 0.00000000e+00}, expected {1.00000000e+00, 0.00000000e+00, 0.00000000e+00, 0.00000000e+00} at (0, 0).
d3d12:8258:41:if_return: Test failed: Got {1.00000000e+00, 1.00000000e+00, 1.00000000e+00, 0.00000000e+00}, expected {1.00000000e+00, 1.00000000e+00, 1.00000000e+00, 1.00000000e+00} at (0, 0).
d3d12:8258:48:if_return: Test failed: Got {0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 0.00000000e+00}, expected {1.00000000e+00, 1.00000000e+00, 1.00000000e+00, 1.00000000e+00} at (0, 0).


and the following test failures on Radv:

d3d12:8258:31:if_return: Test failed: Got {0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 0.00000000e+00}, expected {1.00000000e+00, 0.00000000e+00, 0.00000000e+00, 0.00000000e+00} at (0, 0).
d3d12:8258:34:if_return: Test failed: Got {1.00000000e+00, 0.00000000e+00, 0.00000000e+00, 0.00000000e+00}, expected {1.00000000e+00, 1.00000000e+00, 1.00000000e+00, 0.00000000e+00} at (0, 0).
d3d12:8258:37:if_return: Test failed: Got {1.00000000e+00, 1.00000000e+00, 0.00000000e+00, 0.00000000e+00}, expected {1.00000000e+00, 1.00000000e+00, 1.00000000e+00, 0.00000000e+00} at (0, 0).
d3d12:8258:41:if_return: Test failed: Got {1.00000000e+00, 1.00000000e+00, 1.00000000e+00, 0.00000000e+00}, expected {1.00000000e+00, 1.00000000e+00, 1.00000000e+00, 1.00000000e+00} at (0, 0).
d3d12:8258:48:if_return: Test failed: Got {0.00000000e+00, 0.00000000e+00, 0.00000000e+00, 0.00000000e+00}, expected {1.00000000e+00, 1.00000000e+00, 1.00000000e+00, 1.00000000e+00} at (0, 0).

Comment 1 Samuel Pitoiset 2019-01-08 17:16:00 UTC

One other solution is to set the exact bit when translating spirv to nir.

Comment 2 Jason Ekstrand 2019-01-08 17:17:28 UTC

+idr.  There has been some discussion of this and some different patches on the mailing list for different approaches to solving the problem.  This one gets a bit sticky because it's an area where GL is intentionally lax but Vulkan is supposedly more strict.  It's also an area where breaking IEEE a little is extremely useful for optimization.

Comment 3 GitLab Migration User 2019-09-18 18:13:14 UTC

-- GitLab Migration Automatic Message --

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