10920 lzcnt feature not properly identified on Intel systems

Reviewed by: Garrett D'Amore <garrett@damore.org> Reviewed by: Toomas Soome <tsoome@me.com> Approved by: Richard Lowe <richlowe@richlowe.net>
illumos · May 7, 2019 · 1567de9 · 1567de9
1 parent 36cd012
commit 1567de9
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/usr/src/uts/i86pc/os/cpuid.c b/usr/src/uts/i86pc/os/cpuid.c
@@ -4488,6 +4488,8 @@ cpuid_pass4(cpu_t *cpu, uint_t *hwcap_out)
 		case X86_VENDOR_Intel:
 			if (*edx & CPUID_AMD_EDX_TSCP)
 				hwcap_flags |= AV_386_TSCP;
+			if (*ecx & CPUID_AMD_ECX_LZCNT)
+				hwcap_flags |= AV_386_AMD_LZCNT;
 			/*
 			 * Aarrgh.
 			 * Intel uses a different bit in the same word.