Rename gpu package discover (#7143)

Cleaning up go package naming

discover/gpu_info_darwin.m

@@ -0,0 +1,35 @@
+#import <Foundation/Foundation.h>
+#import <mach/mach.h>
+#include "gpu_info_darwin.h"
+
+uint64_t getRecommendedMaxVRAM() {
+  id<MTLDevice> device = MTLCreateSystemDefaultDevice();
+  uint64_t result = device.recommendedMaxWorkingSetSize;
+  CFRelease(device);
+  return result;
+}
+
+// getPhysicalMemory returns the total physical memory in bytes
+uint64_t getPhysicalMemory() {
+  return [NSProcessInfo processInfo].physicalMemory;
+}
+
+// getFreeMemory returns the total free memory in bytes, including inactive
+// memory that can be reclaimed by the system.
+uint64_t getFreeMemory() {
+  mach_port_t host_port = mach_host_self();
+  mach_msg_type_number_t host_size = sizeof(vm_statistics64_data_t) / sizeof(integer_t);
+  vm_size_t pagesize;
+  vm_statistics64_data_t vm_stat;
+
+  host_page_size(host_port, &pagesize);
+  if (host_statistics64(host_port, HOST_VM_INFO64, (host_info64_t)&vm_stat, &host_size) != KERN_SUCCESS) {
+    return 0;
+  }
+
+  uint64_t free_memory = (uint64_t)vm_stat.free_count * pagesize;
+  free_memory += (uint64_t)vm_stat.speculative_count * pagesize;
+  free_memory += (uint64_t)vm_stat.inactive_count * pagesize;
+
+  return free_memory;
+}