Add cpu_feature test

Author: AntoinePrv

test/CMakeLists.txt

@@ -147,6 +147,7 @@ set(XSIMD_TESTS
     test_complex_power.cpp
     test_complex_trigonometric.cpp
     test_conversion.cpp
+    test_cpu_features.cpp
     test_custom_default_arch.cpp
     test_error_gamma.cpp
     test_explicit_batch_instantiation.cpp

test/test_cpu_features.cpp

@@ -0,0 +1,114 @@
+/***************************************************************************
+ * Copyright (c) Johan Mabille, Sylvain Corlay, Wolf Vollprecht and         *
+ * Martin Renou                                                             *
+ * Copyright (c) QuantStack                                                 *
+ * Copyright (c) Serge Guelton                                              *
+ *                                                                          *
+ * Distributed under the terms of the BSD 3-Clause License.                 *
+ *                                                                          *
+ * The full license is in the file LICENSE, distributed with this software. *
+ ****************************************************************************/
+
+#include <cstdlib>
+#include <string>
+
+#include <doctest/doctest.h>
+
+#include "xsimd/xsimd.hpp"
+
+#define CHECK_IMPLICATION(a, b) CHECK_UNARY(!(a) || (b))
+
+namespace detail
+{
+    void check_env_flag(const char* env_var, const char* feature_name, bool actual)
+    {
+        const char* val = std::getenv(env_var);
+        if (val)
+        {
+            // Doctest struggles with string litteras and const char *
+            auto msg = std::string(env_var) + " = " + val + ", " + feature_name + " = " + (actual ? "true" : "false");
+            INFO(msg);
+            CHECK_EQ(actual, val[0] == '1');
+        }
+    }
+}
+
+#define CHECK_ENV_FEATURE(env_var, feature) detail::check_env_flag(env_var, #feature, feature)
+
+/**
+ * Tests that x86_cpu_features respects the architectural implication chains.
+ *
+ * These are "always true" assertions: if a higher feature is reported, all
+ * features it architecturally implies must also be reported. The test reads
+ * the current CPU's features at runtime and verifies every implication.
+ */
+TEST_CASE("[cpu_features] x86 implication chains")
+{
+    xsimd::x86_cpu_features cpu;
+
+    // SSE implication chain
+    CHECK_IMPLICATION(cpu.sse4_2(), cpu.sse4_1());
+    CHECK_IMPLICATION(cpu.sse4_1(), cpu.ssse3());
+    CHECK_IMPLICATION(cpu.ssse3(), cpu.sse3());
+    CHECK_IMPLICATION(cpu.sse3(), cpu.sse2());
+
+    // AVX implication chain
+    CHECK_IMPLICATION(cpu.avx(), cpu.sse4_2());
+    CHECK_IMPLICATION(cpu.avx2(), cpu.avx());
+    CHECK_IMPLICATION(cpu.fma4(), cpu.avx());
+    CHECK_IMPLICATION(cpu.fma3(), cpu.avx());
+
+    // AVX-512 iplication chain
+    CHECK_IMPLICATION(cpu.avx512f(), cpu.avx2());
+    CHECK_IMPLICATION(cpu.avx512dq(), cpu.avx512f());
+    CHECK_IMPLICATION(cpu.avx512ifma(), cpu.avx512f());
+    CHECK_IMPLICATION(cpu.avx512pf(), cpu.avx512f());
+    CHECK_IMPLICATION(cpu.avx512er(), cpu.avx512f());
+    CHECK_IMPLICATION(cpu.avx512cd(), cpu.avx512f());
+    CHECK_IMPLICATION(cpu.avx512bw(), cpu.avx512f());
+    CHECK_IMPLICATION(cpu.avx512vbmi(), cpu.avx512f());
+    CHECK_IMPLICATION(cpu.avx512vbmi2(), cpu.avx512f());
+    CHECK_IMPLICATION(cpu.avx512vnni_bw(), cpu.avx512bw());
+    CHECK_IMPLICATION(cpu.avxvnni(), cpu.avx2());
+}
+
+
+TEST_CASE("[cpu_features] x86 features from environment")
+{
+    xsimd::x86_cpu_features cpu;
+
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_SSE2", cpu.sse2());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_SSE3", cpu.sse3());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_SSSE3", cpu.ssse3());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_SSE4_1", cpu.sse4_1());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_SSE4_2", cpu.sse4_2());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_FMA3", cpu.fma3());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_FMA4", cpu.fma4());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_AVX", cpu.avx());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_AVX2", cpu.avx2());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_AVX512F", cpu.avx512f());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_AVX512BW", cpu.avx512bw());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_AVX512CD", cpu.avx512cd());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_AVX512DQ", cpu.avx512dq());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_AVXVNNI", cpu.avxvnni());
+}
+
+TEST_CASE("[cpu_features] arm implication chains")
+{
+    xsimd::arm_cpu_features cpu;
+
+    CHECK_IMPLICATION(cpu.neon64(), cpu.neon());
+    CHECK_IMPLICATION(cpu.sve(), cpu.neon64());
+    CHECK_IMPLICATION(cpu.i8mm(), cpu.neon64());
+}
+
+TEST_CASE("[cpu_features] arm features from environment")
+{
+    xsimd::arm_cpu_features cpu;
+
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_NEON", cpu.neon());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_NEON64", cpu.neon64());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_SVE", cpu.sve());
+    CHECK_ENV_FEATURE("XSIMD_TEST_CPU_ASSUME_I8MM", cpu.i8mm());
+}
+