sys/info: add feature detection for Darwin and Linux ARM

core/sys/info/cpu_arm.odin

@@ -1,26 +1,55 @@
 //+build arm32, arm64
 package sysinfo
 
-// TODO: Set up an enum with the ARM equivalent of the above.
-CPU_Feature :: enum u64 {}
+CPU_Feature :: enum u64 {
+	// Advanced SIMD & floating-point capabilities:
+	asimd,         // General support for Advanced SIMD instructions/neon.
+	floatingpoint, // General support for floating-point instructions.
+	asimdhp,       // Advanced SIMD half-precision conversion instructions.
+	bf16,          // Storage and arithmetic instructions of the Brain Floating Point (BFloat16) data type.
+	fcma,          // Floating-point complex number instructions.
+	fhm,           // Floating-point half-precision multiplication instructions.
+	fp16,          // General half-precision floating-point data processing instructions.
+	frint,         // Floating-point to integral valued floating-point number rounding instructions.
+	i8mm,          // Advanced SIMD int8 matrix multiplication instructions.
+	jscvt,         // JavaScript conversion instruction.
+	rdm,           // Advanced SIMD rounding double multiply accumulate instructions.
 
-cpu_features: Maybe(CPU_Feature)
-cpu_name:     Maybe(string)
+	flagm,  // Condition flag manipulation instructions.
+	flagm2, // Enhancements to condition flag manipulation instructions.
+	crc32,  // CRC32 instructions.
 
-@(init, private)
-init_cpu_features :: proc "c" () {
+	lse,    // Atomic instructions to support large systems.
+	lse2,   // Changes to single-copy atomicity and alignment requirements for loads and stores for large systems.
+	lrcpc,  // Load-acquire Release Consistency processor consistent (RCpc) instructions.
+	lrcpc2, // Load-acquire Release Consistency processor consistent (RCpc) instructions version 2.
+
+	aes,
+	pmull,
+	sha1,
+	sha256,
+	sha512,
+	sha3,
+
+	sb,   // Barrier instruction to control speculation.
+	ssbs, // Instructions to control speculation of loads and stores.
 }
 
+CPU_Features :: distinct bit_set[CPU_Feature; u64]
+
+cpu_features: Maybe(CPU_Features)
+cpu_name: Maybe(string)
+
 @(private)
-_cpu_name_buf: [72]u8
+cpu_name_buf: [128]byte
 
 @(init, private)
-init_cpu_name :: proc "c" () {
-	when ODIN_ARCH == .arm32 {
-		copy(_cpu_name_buf[:], "ARM")
-		cpu_name = string(_cpu_name_buf[:3])
+init_cpu_name :: proc "contextless" () {
+	when ODIN_ARCH == .arm64 {
+		copy(cpu_name_buf[:], "ARM64")
+		cpu_name = string(cpu_name_buf[:len("ARM64")])
 	} else {
-		copy(_cpu_name_buf[:], "ARM64")
-		cpu_name = string(_cpu_name_buf[:5])
+		copy(cpu_name_buf[:], "ARM")
+		cpu_name = string(cpu_name_buf[:len("ARM")])
 	}
-}
+}