Add libgmp 6.2.0 to third_party
Don't build it yet. That will come in the next review.
Change-Id: Idf3266558165e5ab45f4a41c98cc8c838c8244d5
diff --git a/third_party/gmp/tune/x86_64.asm b/third_party/gmp/tune/x86_64.asm
new file mode 100644
index 0000000..b7ec44c
--- /dev/null
+++ b/third_party/gmp/tune/x86_64.asm
@@ -0,0 +1,55 @@
+dnl x86 pentium time stamp counter access routine.
+
+dnl Copyright 1999, 2000, 2003-2005 Free Software Foundation, Inc.
+
+dnl This file is part of the GNU MP Library.
+dnl
+dnl The GNU MP Library is free software; you can redistribute it and/or modify
+dnl it under the terms of either:
+dnl
+dnl * the GNU Lesser General Public License as published by the Free
+dnl Software Foundation; either version 3 of the License, or (at your
+dnl option) any later version.
+dnl
+dnl or
+dnl
+dnl * the GNU General Public License as published by the Free Software
+dnl Foundation; either version 2 of the License, or (at your option) any
+dnl later version.
+dnl
+dnl or both in parallel, as here.
+dnl
+dnl The GNU MP Library is distributed in the hope that it will be useful, but
+dnl WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+dnl or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+dnl for more details.
+dnl
+dnl You should have received copies of the GNU General Public License and the
+dnl GNU Lesser General Public License along with the GNU MP Library. If not,
+dnl see https://www.gnu.org/licenses/.
+
+
+include(`../config.m4')
+
+
+C void speed_cyclecounter (unsigned p[2]);
+C
+C Get the pentium rdtsc cycle counter, storing the least significant word in
+C p[0] and the most significant in p[1].
+C
+C cpuid is used to serialize execution. On big measurements this won't be
+C significant but it may help make small single measurements more accurate.
+
+PROLOGUE(speed_cyclecounter)
+
+ C rdi p
+
+ movq %rbx, %r10
+ xorl %eax, %eax
+ cpuid
+ rdtsc
+ movl %eax, (%rdi)
+ movl %edx, 4(%rdi)
+ movq %r10, %rbx
+ ret
+EPILOGUE()