From 2f64e493debba881b45d1636999476c9ee921326 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Leclercq?= <lynix680@gmail.com>
Date: Tue, 28 Dec 2021 11:49:53 +0100
Subject: [PATCH] UnitTests/Shader: Add sanitization and optimizations unit
 tests

---
 tests/Engine/Shader/Optimizations.cpp | 145 ++++++++++++++++++++++++++
 tests/Engine/Shader/Sanitizations.cpp |  81 ++++++++++++++
 2 files changed, 226 insertions(+)
 create mode 100644 tests/Engine/Shader/Optimizations.cpp
 create mode 100644 tests/Engine/Shader/Sanitizations.cpp

diff --git a/tests/Engine/Shader/Optimizations.cpp b/tests/Engine/Shader/Optimizations.cpp
new file mode 100644
index 000000000..73b19192d
--- /dev/null
+++ b/tests/Engine/Shader/Optimizations.cpp
@@ -0,0 +1,145 @@
+#include <Engine/Shader/ShaderUtils.hpp>
+#include <Nazara/Core/File.hpp>
+#include <Nazara/Core/StringExt.hpp>
+#include <Nazara/Shader/ShaderBuilder.hpp>
+#include <Nazara/Shader/ShaderLangParser.hpp>
+#include <Nazara/Shader/Ast/AstOptimizer.hpp>
+#include <Nazara/Shader/Ast/SanitizeVisitor.hpp>
+#include <catch2/catch.hpp>
+#include <cctype>
+
+void ExpectOptimization(std::string_view sourceCode, std::string_view expectedOptimizedResult)
+{
+	Nz::ShaderAst::StatementPtr shader;
+	REQUIRE_NOTHROW(shader = Nz::ShaderLang::Parse(sourceCode));
+	REQUIRE_NOTHROW(shader = Nz::ShaderAst::Sanitize(*shader));
+	REQUIRE_NOTHROW(shader = Nz::ShaderAst::Optimize(*shader));
+
+	ExpectNZSL(*shader, expectedOptimizedResult);
+}
+
+TEST_CASE("optimizations", "[Shader]")
+{
+	WHEN("propaging constants")
+	{
+		ExpectOptimization(R"(
+[entry(frag)]
+fn main()
+{
+	let output = 8.0 * (7.0 + 5.0) * 2.0 / 4.0 - 6.0;
+}
+)", R"(
+[entry(frag)]
+fn main()
+{
+	let output: f32 = 42.000000;
+)");
+	}
+
+	WHEN("propaging vector constants")
+	{
+		ExpectOptimization(R"(
+[entry(frag)]
+fn main()
+{
+	let output = vec4<f32>(8.0, 2.0, -7.0, 0.0) * (7.0 + 5.0) * 2.0 / 4.0;
+}
+)", R"(
+[entry(frag)]
+fn main()
+{
+	let output: vec4<f32> = vec4<f32>(48.000000, 12.000000, -42.000000, 0.000000);
+)");
+	}
+
+	WHEN("eliminating simple branch")
+	{
+		ExpectOptimization(R"(
+[entry(frag)]
+fn main()
+{
+	if (5 + 3 < 2)
+		discard;
+}
+)", R"(
+[entry(frag)]
+fn main()
+{
+	
+}
+)");
+	}
+
+	WHEN("eliminating multiple branches")
+	{
+		ExpectOptimization(R"(
+[entry(frag)]
+fn main()
+{
+	let output = 0.0;
+	if (5 <= 3)
+		output = 5.0;
+	else if (4 <= 3)
+		output = 4.0;
+	else if (3 <= 3)
+		output = 3.0;
+	else if (2 <= 3)
+		output = 2.0;
+	else if (1 <= 3)
+		output = 1.0;
+	else
+		output = 0.0;
+}
+)", R"(
+[entry(frag)]
+fn main()
+{
+	let output: f32 = 0.000000;
+	output = 3.000000;
+}
+)");
+	}
+
+
+	WHEN("eliminating multiple splitted branches")
+	{
+		ExpectOptimization(R"(
+[entry(frag)]
+fn main()
+{
+	let output = 0.0;
+	if (5 <= 3)
+		output = 5.0;
+	else
+	{
+		if (4 <= 3)
+			output = 4.0;
+		else
+		{
+			if (3 <= 3)
+				output = 3.0;
+			else
+			{
+				if (2 <= 3)
+					output = 2.0;
+				else
+				{
+					if (1 <= 3)
+						output = 1.0;
+					else
+						output = 0.0;
+				}
+			}
+		}
+	}
+}
+)", R"(
+[entry(frag)]
+fn main()
+{
+	let output: f32 = 0.000000;
+	output = 3.000000;
+}
+)");
+	}
+}
diff --git a/tests/Engine/Shader/Sanitizations.cpp b/tests/Engine/Shader/Sanitizations.cpp
new file mode 100644
index 000000000..9a376c0a8
--- /dev/null
+++ b/tests/Engine/Shader/Sanitizations.cpp
@@ -0,0 +1,81 @@
+#include <Engine/Shader/ShaderUtils.hpp>
+#include <Nazara/Core/File.hpp>
+#include <Nazara/Core/StringExt.hpp>
+#include <Nazara/Shader/ShaderBuilder.hpp>
+#include <Nazara/Shader/ShaderLangParser.hpp>
+#include <Nazara/Shader/Ast/SanitizeVisitor.hpp>
+#include <catch2/catch.hpp>
+#include <cctype>
+
+TEST_CASE("sanitizing", "[Shader]")
+{
+	WHEN("splitting branches")
+	{
+		std::string_view nzslSource = R"(
+struct inputStruct
+{
+	value: f32
+}
+
+external
+{
+	[set(0), binding(0)] data: uniform<inputStruct>
+}
+
+[entry(frag)]
+fn main()
+{
+	let value: f32;
+	if (data.value > 3.0)
+		value = 3.0;
+	else if (data.value > 2.0)
+		value = 2.0;
+	else if (data.value > 1.0)
+		value = 1.0;
+	else
+		value = 0.0;
+}
+)";
+
+		Nz::ShaderAst::StatementPtr shader = Nz::ShaderLang::Parse(nzslSource);
+
+		Nz::ShaderAst::SanitizeVisitor::Options options;
+		options.splitMultipleBranches = true;
+
+		REQUIRE_NOTHROW(shader = Nz::ShaderAst::Sanitize(*shader, options));
+
+		ExpectNZSL(*shader, R"(
+[entry(frag)]
+fn main()
+{
+	let value: f32;
+	if (data.value > (3.000000))
+	{
+		value = 3.000000;
+	}
+	else
+	{
+		if (data.value > (2.000000))
+		{
+			value = 2.000000;
+		}
+		else
+		{
+			if (data.value > (1.000000))
+			{
+				value = 1.000000;
+			}
+			else
+			{
+				value = 0.000000;
+			}
+			
+		}
+		
+	}
+	
+}
+)");
+
+	}
+}