Add support for multiple microarchitectures in single binary

[vpp.git] / vppinfra / vppinfra / cpu.h

diff --git a/vppinfra/vppinfra/cpu.h b/vppinfra/vppinfra/cpu.h
index 79cdf74..961af70 100644 (file)
--- a/vppinfra/vppinfra/cpu.h
+++ b/vppinfra/vppinfra/cpu.h
@@ -16,7 +16,83 @@
 #ifndef included_clib_cpu_h
 #define included_clib_cpu_h
 
+#include <vppinfra/format.h>
+
+/*
+ * multiarchitecture support. Adding new entry will produce
+ * new graph node function variant optimized for specific cpu
+ * microarchitecture.
+ * Order is important for runtime selection, as 1st match wins...
+ */
+
+#if __x86_64__ && CLIB_DEBUG == 0
+#define foreach_march_variant(macro, x) \
+  macro(avx2,  x, "arch=core-avx2")
+#else
+#define foreach_march_variant(macro, x)
+#endif
+
+
+#if __GNUC__ > 4  && !__clang__
+#define CLIB_CPU_OPTIMIZED __attribute__ ((optimize ("tree-vectorize")))
+#else
+#define CLIB_CPU_OPTIMIZED
+#endif
+
+
+#define CLIB_MULTIARCH_ARCH_CHECK(arch, fn, tgt)                       \
+  if (clib_cpu_supports_ ## arch())                                    \
+    return & fn ## _ ##arch;
+
+#define CLIB_MULTIARCH_SELECT_FN(fn,...)                               \
+  __VA_ARGS__ void * fn ## _multiarch_select(void)                     \
+{                                                                      \
+  foreach_march_variant(CLIB_MULTIARCH_ARCH_CHECK, fn)                 \
+  return & fn;                                                         \
+}
+
+#if __x86_64__
+#include "cpuid.h"
+
+#define foreach_x86_64_flags \
+_ (sse3,     1, ecx, 0)   \
+_ (ssse3,    1, ecx, 9)   \
+_ (sse41,    1, ecx, 19)  \
+_ (sse42,    1, ecx, 20)  \
+_ (avx,      1, ecx, 28)  \
+_ (avx2,     7, ebx, 5)   \
+_ (avx512f,  7, ebx, 16)  \
+_ (aes,      1, ecx, 25)  \
+_ (sha,      7, ebx, 29)
+
+static inline int
+clib_get_cpuid(const u32 lev, u32 * eax, u32 *ebx, u32 * ecx, u32 * edx)
+{
+  if ((u32) __get_cpuid_max (0x80000000 & lev, 0) < lev)
+    return 0;
+  if (lev == 7)
+    __cpuid_count(lev, 0, *eax, *ebx, *ecx, *edx);
+  else
+    __cpuid(lev, *eax, *ebx, *ecx, *edx);
+  return 1;
+}
+
+
+#define _(flag, func, reg, bit) \
+static inline int                                                      \
+clib_cpu_supports_ ## flag()                                           \
+{                                                                      \
+  u32 __attribute__((unused)) eax, ebx = 0, ecx = 0, edx  = 0;         \
+  clib_get_cpuid (func, &eax, &ebx, &ecx, &edx);                       \
+                                                                       \
+  return ((reg & (1 << bit)) != 0);                                    \
+}
+  foreach_x86_64_flags
+#undef _
+#endif
+
 format_function_t format_cpu_uarch;
 format_function_t format_cpu_model_name;
+format_function_t format_cpu_flags;
 
-#endif
\ No newline at end of file
+#endif