7 files changed, 46 insertions, 2 deletions
diff --git a/vendor/golang.org/x/sys/cpu/asm_aix_ppc64.s b/vendor/golang.org/x/sys/cpu/asm_aix_ppc64.s
index 6b4027b3..db9171c2 100644
--- a/vendor/golang.org/x/sys/cpu/asm_aix_ppc64.s
+++ b/vendor/golang.org/x/sys/cpu/asm_aix_ppc64.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build gc
 // +build gc
 
 #include "textflag.h"
diff --git a/vendor/golang.org/x/sys/cpu/cpu_arm64.s b/vendor/golang.org/x/sys/cpu/cpu_arm64.s
index cfc08c97..c61f95a0 100644
--- a/vendor/golang.org/x/sys/cpu/cpu_arm64.s
+++ b/vendor/golang.org/x/sys/cpu/cpu_arm64.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build gc
 // +build gc
 
 #include "textflag.h"
diff --git a/vendor/golang.org/x/sys/cpu/cpu_gc_x86.go b/vendor/golang.org/x/sys/cpu/cpu_gc_x86.go
index fa7cdb9b..3298a87e 100644
--- a/vendor/golang.org/x/sys/cpu/cpu_gc_x86.go
+++ b/vendor/golang.org/x/sys/cpu/cpu_gc_x86.go
@@ -15,3 +15,7 @@ func cpuid(eaxArg, ecxArg uint32) (eax, ebx, ecx, edx uint32)
 // xgetbv with ecx = 0 is implemented in cpu_x86.s for gc compiler
 // and in cpu_gccgo.c for gccgo.
 func xgetbv() (eax, edx uint32)
+
+// darwinSupportsAVX512 is implemented in cpu_x86.s for gc compiler
+// and in cpu_gccgo_x86.go for gccgo.
+func darwinSupportsAVX512() bool
diff --git a/vendor/golang.org/x/sys/cpu/cpu_gccgo_x86.go b/vendor/golang.org/x/sys/cpu/cpu_gccgo_x86.go
index 8478a6d5..863d415a 100644
--- a/vendor/golang.org/x/sys/cpu/cpu_gccgo_x86.go
+++ b/vendor/golang.org/x/sys/cpu/cpu_gccgo_x86.go
@@ -25,3 +25,9 @@ func xgetbv() (eax, edx uint32) {
 	gccgoXgetbv(&a, &d)
 	return a, d
 }
+
+// gccgo doesn't build on Darwin, per:
+// https://github.com/Homebrew/homebrew-core/blob/HEAD/Formula/gcc.rb#L76
+func darwinSupportsAVX512() bool {
+	return false
+}
diff --git a/vendor/golang.org/x/sys/cpu/cpu_s390x.s b/vendor/golang.org/x/sys/cpu/cpu_s390x.s
index 964946df..96f81e20 100644
--- a/vendor/golang.org/x/sys/cpu/cpu_s390x.s
+++ b/vendor/golang.org/x/sys/cpu/cpu_s390x.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build gc
 // +build gc
 
 #include "textflag.h"
diff --git a/vendor/golang.org/x/sys/cpu/cpu_x86.go b/vendor/golang.org/x/sys/cpu/cpu_x86.go
index fd380c0a..54ca4667 100644
--- a/vendor/golang.org/x/sys/cpu/cpu_x86.go
+++ b/vendor/golang.org/x/sys/cpu/cpu_x86.go
@@ -87,8 +87,14 @@ func archInit() {
 		// Check if XMM and YMM registers have OS support.
 		osSupportsAVX = isSet(1, eax) && isSet(2, eax)
 
-		// Check if OPMASK and ZMM registers have OS support.
-		osSupportsAVX512 = osSupportsAVX && isSet(5, eax) && isSet(6, eax) && isSet(7, eax)
+		if runtime.GOOS == "darwin" {
+			// Check darwin commpage for AVX512 support. Necessary because:
+			// https://github.com/apple/darwin-xnu/blob/0a798f6738bc1db01281fc08ae024145e84df927/osfmk/i386/fpu.c#L175-L201
+			osSupportsAVX512 = osSupportsAVX && darwinSupportsAVX512()
+		} else {
+			// Check if OPMASK and ZMM registers have OS support.
+			osSupportsAVX512 = osSupportsAVX && isSet(5, eax) && isSet(6, eax) && isSet(7, eax)
+		}
 	}
 
 	X86.HasAVX = isSet(28, ecx1) && osSupportsAVX
diff --git a/vendor/golang.org/x/sys/cpu/cpu_x86.s b/vendor/golang.org/x/sys/cpu/cpu_x86.s
index 2f557a58..b748ba52 100644
--- a/vendor/golang.org/x/sys/cpu/cpu_x86.s
+++ b/vendor/golang.org/x/sys/cpu/cpu_x86.s
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build (386 || amd64 || amd64p32) && gc
 // +build 386 amd64 amd64p32
 // +build gc
 
@@ -25,3 +26,27 @@ TEXT ·xgetbv(SB),NOSPLIT,$0-8
 	MOVL AX, eax+0(FP)
 	MOVL DX, edx+4(FP)
 	RET
+
+// func darwinSupportsAVX512() bool
+TEXT ·darwinSupportsAVX512(SB), NOSPLIT, $0-1
+    MOVB    $0, ret+0(FP) // default to false
+#ifdef GOOS_darwin   // return if not darwin
+#ifdef GOARCH_amd64  // return if not amd64
+// These values from:
+// https://github.com/apple/darwin-xnu/blob/xnu-4570.1.46/osfmk/i386/cpu_capabilities.h
+#define commpage64_base_address         0x00007fffffe00000
+#define commpage64_cpu_capabilities64   (commpage64_base_address+0x010)
+#define commpage64_version              (commpage64_base_address+0x01E)
+#define hasAVX512F                      0x0000004000000000
+    MOVQ    $commpage64_version, BX
+    CMPW    (BX), $13  // cpu_capabilities64 undefined in versions < 13
+    JL      no_avx512
+    MOVQ    $commpage64_cpu_capabilities64, BX
+    MOVQ    $hasAVX512F, CX
+    TESTQ   (BX), CX
+    JZ      no_avx512
+    MOVB    $1, ret+0(FP)
+no_avx512:
+#endif
+#endif
+    RET