x/crypto/blake2b: SSE4.1 is bit 19, not 15.
I missed this in the initial review but this will cause blake2b to
SIGILL on, at least, some Atom chips.
Fixes golang/go#18113.
Change-Id: I0c16319df71f3ce4a38411ad4c4e9d3871fd9533
Reviewed-on: https://go-review.googlesource.com/33830
Run-TryBot: Adam Langley <agl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/blake2b/blake2b_amd64.s b/blake2b/blake2b_amd64.s
index 3017cf0..7a876ba 100644
--- a/blake2b/blake2b_amd64.s
+++ b/blake2b/blake2b_amd64.s
@@ -269,7 +269,7 @@
TEXT ·supportSSE4(SB), 4, $0-1
MOVL $1, AX
CPUID
- SHRL $15, CX // Bit 15 indicates SSE4 support
+ SHRL $19, CX // Bit 19 indicates SSE4 support
ANDL $1, CX // CX != 0 if support SSE4
MOVB CX, ret+0(FP)
RET
