dawn_native: handle NaN lod values in samplers

For samplers with NaN mLodMinClamp or mLodMaxClamp, the equality
operator returned false.
Adds checks for finite values, and also early returns if two pointers
are equal.

Bug: dawn:143, chromium:965633
Change-Id: Id5998d6eec275af0fbe30e3b4fcb3eed4fe64c6a
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/7401
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
Commit-Queue: Idan Raiter <idanr@google.com>

BUILD.gn

@@ -13,10 +13,10 @@
 # limitations under the License.
 
 import("//build_overrides/build.gni")
+import("generator/dawn_generator.gni")
 import("scripts/dawn_component.gni")
 import("scripts/dawn_features.gni")
 import("scripts/dawn_overrides_with_defaults.gni")
-import("generator/dawn_generator.gni")
 
 import("//testing/test.gni")
 
@@ -579,6 +579,7 @@ test("dawn_unittests") {
     "src/tests/unittests/validation/RenderPassDescriptorValidationTests.cpp",
     "src/tests/unittests/validation/RenderPassValidationTests.cpp",
     "src/tests/unittests/validation/RenderPipelineValidationTests.cpp",
+    "src/tests/unittests/validation/SamplerValidationTests.cpp",
     "src/tests/unittests/validation/ShaderModuleValidationTests.cpp",
     "src/tests/unittests/validation/TextureValidationTests.cpp",
     "src/tests/unittests/validation/TextureViewValidationTests.cpp",

src/dawn_native/Sampler.cpp

@@ -18,6 +18,8 @@
 #include "dawn_native/Device.h"
 #include "dawn_native/ValidationUtils_autogen.h"
 
+#include <cmath>
+
 namespace dawn_native {
 
     MaybeError ValidateSamplerDescriptor(DeviceBase*, const SamplerDescriptor* descriptor) {
@@ -25,6 +27,10 @@ namespace dawn_native {
             return DAWN_VALIDATION_ERROR("nextInChain must be nullptr");
         }
 
+        if (!std::isfinite(descriptor->lodMinClamp) || !std::isfinite(descriptor->lodMaxClamp)) {
+            return DAWN_VALIDATION_ERROR("LOD must be finite");
+        }
+
         if (descriptor->lodMinClamp < 0 || descriptor->lodMaxClamp < 0) {
             return DAWN_VALIDATION_ERROR("LOD must be positive");
         }
@@ -95,6 +101,15 @@ namespace dawn_native {
     }
 
     bool SamplerBase::EqualityFunc::operator()(const SamplerBase* a, const SamplerBase* b) const {
+        if (a == b) {
+            return true;
+        }
+
+        ASSERT(std::isfinite(a->mLodMinClamp));
+        ASSERT(std::isfinite(b->mLodMinClamp));
+        ASSERT(std::isfinite(a->mLodMaxClamp));
+        ASSERT(std::isfinite(b->mLodMaxClamp));
+
         return a->mAddressModeU == b->mAddressModeU && a->mAddressModeV == b->mAddressModeV &&
                a->mAddressModeW == b->mAddressModeW && a->mMagFilter == b->mMagFilter &&
                a->mMinFilter == b->mMinFilter && a->mMipmapFilter == b->mMipmapFilter &&

src/tests/unittests/validation/SamplerValidationTests.cpp

@@ -0,0 +1,49 @@
+// Copyright 2019 The Dawn Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "tests/unittests/validation/ValidationTest.h"
+
+#include "utils/DawnHelpers.h"
+
+#include <cmath>
+
+namespace {
+
+    class SamplerValidationTest : public ValidationTest {};
+
+    // Test NaN and INFINITY values are not allowed
+    TEST_F(SamplerValidationTest, InvalidLOD) {
+        {
+            dawn::SamplerDescriptor samplerDesc = utils::GetDefaultSamplerDescriptor();
+            samplerDesc.lodMinClamp = NAN;
+            ASSERT_DEVICE_ERROR(device.CreateSampler(&samplerDesc));
+        }
+        {
+            dawn::SamplerDescriptor samplerDesc = utils::GetDefaultSamplerDescriptor();
+            samplerDesc.lodMaxClamp = NAN;
+            ASSERT_DEVICE_ERROR(device.CreateSampler(&samplerDesc));
+        }
+        {
+            dawn::SamplerDescriptor samplerDesc = utils::GetDefaultSamplerDescriptor();
+            samplerDesc.lodMinClamp = INFINITY;
+            ASSERT_DEVICE_ERROR(device.CreateSampler(&samplerDesc));
+        }
+        {
+            dawn::SamplerDescriptor samplerDesc = utils::GetDefaultSamplerDescriptor();
+            samplerDesc.lodMaxClamp = INFINITY;
+            ASSERT_DEVICE_ERROR(device.CreateSampler(&samplerDesc));
+        }
+    }
+
+}  // anonymous namespace