From 37f7bbad77cd7dfed36eebf6bb9ee4c111d48962 Mon Sep 17 00:00:00 2001
From: Geoffrey McRae <geoff@hostfission.com>
Date: Sat, 3 Oct 2026 09:11:01 +1000
Subject: [PATCH] [common] cpuinfo: move feature queries to platform code

---
 common/include/common/cpuinfo.h       |  4 ++++
 common/src/cpuinfo.c                  | 29 +++------------------------
 common/src/platform/linux/cpuinfo.c   | 27 +++++++++++++++++++++++++
 common/src/platform/windows/cpuinfo.c | 11 ++++++++++
 4 files changed, 45 insertions(+), 26 deletions(-)

diff --git a/common/include/common/cpuinfo.h b/common/include/common/cpuinfo.h
index 474fef37..c76703e2 100644
--- a/common/include/common/cpuinfo.h
+++ b/common/include/common/cpuinfo.h
@@ -23,6 +23,10 @@
 
 #include <stddef.h>
 #include <stdbool.h>
+#include <stdint.h>
+
+void     platform_cpuInfoCPUID(int registers[4], int leaf, int subleaf);
+uint64_t platform_cpuInfoXGETBV(unsigned int index);
 
 bool cpuInfo_get(char * model, size_t modelSize, int * procs, int * cores,
   int * sockets);
diff --git a/common/src/cpuinfo.c b/common/src/cpuinfo.c
index fcda820e..4a5d8cfd 100644
--- a/common/src/cpuinfo.c
+++ b/common/src/cpuinfo.c
@@ -50,15 +50,7 @@ const CPUInfoFeatures * cpuInfo_getFeatures(void)
   int cpuid[4] = {0};
 
   // leaf1
-  asm volatile
-  (
-    "cpuid;"
-    : "=a" (cpuid[0]),
-      "=b" (cpuid[1]),
-      "=c" (cpuid[2]),
-      "=d" (cpuid[3])
-    : "a" (1)
-  );
+  platform_cpuInfoCPUID(cpuid, 1, 0);
 
   features.sse     = cpuid[3] & (1 << 25);
   features.sse2    = cpuid[3] & (1 << 26);
@@ -74,15 +66,7 @@ const CPUInfoFeatures * cpuInfo_getFeatures(void)
   features.avx     = cpuid[2] & (1 << 28);
 
   // leaf7
-  asm volatile
-  (
-    "cpuid;"
-    : "=a" (cpuid[0]),
-      "=b" (cpuid[1]),
-      "=c" (cpuid[2]),
-      "=d" (cpuid[3])
-    : "a" (7), "c" (0)
-  );
+  platform_cpuInfoCPUID(cpuid, 7, 0);
 
   features.avx2 = cpuid[1] & (1 << 5);
   features.bmi1 = cpuid[2] & (1 << 3);
@@ -90,14 +74,7 @@ const CPUInfoFeatures * cpuInfo_getFeatures(void)
 
   if (features.osxsave && features.avx)
   {
-    int xgetbv = 0;
-    asm volatile
-    (
-      "xgetbv;"
-      : "=a" (xgetbv)
-      : "c" (0)
-      : "edx"
-    );
+    const uint64_t xgetbv = platform_cpuInfoXGETBV(0);
 
     if (!(xgetbv & 0x6))
     {
diff --git a/common/src/platform/linux/cpuinfo.c b/common/src/platform/linux/cpuinfo.c
index 574f31b7..2d178a43 100644
--- a/common/src/platform/linux/cpuinfo.c
+++ b/common/src/platform/linux/cpuinfo.c
@@ -27,6 +27,33 @@
 #include <string.h>
 #include <ctype.h>
 
+void platform_cpuInfoCPUID(int registers[4], int leaf, int subleaf)
+{
+  asm volatile
+  (
+    "cpuid;"
+    : "=a" (registers[0]),
+      "=b" (registers[1]),
+      "=c" (registers[2]),
+      "=d" (registers[3])
+    : "a" (leaf), "c" (subleaf)
+  );
+}
+
+uint64_t platform_cpuInfoXGETBV(unsigned int index)
+{
+  uint32_t low;
+  uint32_t high;
+  asm volatile
+  (
+    "xgetbv;"
+    : "=a" (low), "=d" (high)
+    : "c" (index)
+  );
+
+  return ((uint64_t)high << 32) | low;
+}
+
 bool cpuInfo_get(char * model, size_t modelSize, int * procs, int * cores,
   int * sockets)
 {
diff --git a/common/src/platform/windows/cpuinfo.c b/common/src/platform/windows/cpuinfo.c
index 9a0c7fd2..8ce60674 100644
--- a/common/src/platform/windows/cpuinfo.c
+++ b/common/src/platform/windows/cpuinfo.c
@@ -22,8 +22,19 @@
 #include "common/debug.h"
 #include "common/windebug.h"
 
+#include <intrin.h>
 #include <windows.h>
 
+void platform_cpuInfoCPUID(int registers[4], int leaf, int subleaf)
+{
+  __cpuidex(registers, leaf, subleaf);
+}
+
+uint64_t platform_cpuInfoXGETBV(unsigned int index)
+{
+  return _xgetbv(index);
+}
+
 static bool getCPUModel(char * model, size_t modelSize)
 {
   if (!model)