[Gmp-commit] /var/hg/gmp: 4 new changesets

[mercurial at gmplib.org]

details:   /var/hg/gmp/rev/49e3af448fb6
changeset: 16314:49e3af448fb6
user:      Torbjorn Granlund <tege at gmplib.org>
date:      Thu Feb 27 17:13:42 2014 +0100
description:
Revert "coreihwl" to "coreisbr" if cpuid indicates that BMI2 is missing.

details:   /var/hg/gmp/rev/10fb7d0dbd3d
changeset: 16315:10fb7d0dbd3d
user:      Torbjorn Granlund <tege at gmplib.org>
date:      Thu Feb 27 17:15:55 2014 +0100
description:
Zero ecx for the benefit of new BMI2 feature test.

details:   /var/hg/gmp/rev/775b88c58942
changeset: 16316:775b88c58942
user:      Torbjorn Granlund <tege at gmplib.org>
date:      Thu Feb 27 17:17:33 2014 +0100
description:
(__gmpn_cpuvec_init): Run CPUVEC_SETUP_coreihwl conditionally on BMI2 availability.

details:   /var/hg/gmp/rev/07a2dde2c971
changeset: 16317:07a2dde2c971
user:      Torbjorn Granlund <tege at gmplib.org>
date:      Thu Feb 27 17:17:50 2014 +0100
description:
ChangeLog

diffstat:

 ChangeLog                    |  13 +++++++++++++
 config.guess                 |  15 +++++++++++++++
 mpn/x86_64/fat/fat.c         |   6 +++++-
 mpn/x86_64/fat/fat_entry.asm |   6 ++++--
 4 files changed, 37 insertions(+), 3 deletions(-)

diffs (112 lines):

diff -r 8b074a2e0134 -r 07a2dde2c971 ChangeLog
--- a/ChangeLog	Thu Feb 27 10:43:48 2014 +0100
+++ b/ChangeLog	Thu Feb 27 17:17:50 2014 +0100
@@ -1,3 +1,16 @@
+2014-02-27  Torbjorn Granlund  <tege at gmplib.org>
+
+	* mpn/x86_64/fat/fat_entry.asm: Zero ecx for the benefit of new BMI2
+	feature test.
+
+	* mpn/x86_64/fat/fat.c (__gmpn_cpuvec_init): Run CPUVEC_SETUP_coreihwl
+	conditionally on BMI2 availability.
+
+	* config.guess: Revert "coreihwl" to "coreisbr" if cpuid indicates that
+	BMI2 is missing.
+	(x86 cpuid, 2 variants): Zero ecx for the benefit of new BMI2 feature
+	test.
+
 2014-02-21 Marco Bodrato <bodrato at mail.dm.unipi.it>
 
 	* mini-gmp/mini-gmp.c (mpn_sqrtrem): New function.
diff -r 8b074a2e0134 -r 07a2dde2c971 config.guess
--- a/config.guess	Thu Feb 27 10:43:48 2014 +0100
+++ b/config.guess	Thu Feb 27 17:17:50 2014 +0100
@@ -814,6 +814,16 @@
           else if (model == 0x4f) cpu_64bit = 1, modelstr = "coreibwl"; /* Broadwell server */
           else if (model == 0x56) cpu_64bit = 1, modelstr = "coreibwl"; /* Broadwell microserver */
           else cpu_64bit = 1, modelstr = "corei"; /* default */
+
+	  if (strcmp (modelstr, "coreihwl") == 0)
+	    {
+	      /* Some Haswells lack BMI2.  Let them appear as Sandybridges for
+		 now.  */
+	      CPUID (dummy_string, 7);
+	      if ((dummy_string[0 + 8 / 8] & (1 << (8 % 8))) == 0)
+		modelstr = "coreisbr";
+	    }
+
 	  break;
 	case 15:
 	  cpu_64bit = 1, modelstr = "pentium4";
@@ -900,6 +910,9 @@
 }
 EOF
 
+# The rcx/ecx zeroing here and in the variant below is needed for the BMI2
+# check.
+
   cat <<EOF >${dummy}0.s
 	.globl cpuid
 	.globl _cpuid
@@ -908,6 +921,7 @@
 	push	%rbx
 	mov	%rdx, %r8
 	mov	%ecx, %eax
+	xor	%ecx, %ecx
 	.byte	0x0f
 	.byte	0xa2
 	mov	%ebx, (%r8)
@@ -939,6 +953,7 @@
 	pushl %esi
 	pushl %ebx
 	movl 24(%esp),%eax
+	xor	%ecx, %ecx
 	.byte 0x0f
 	.byte 0xa2
 	movl 20(%esp),%esi
diff -r 8b074a2e0134 -r 07a2dde2c971 mpn/x86_64/fat/fat.c
--- a/mpn/x86_64/fat/fat.c	Thu Feb 27 10:43:48 2014 +0100
+++ b/mpn/x86_64/fat/fat.c	Thu Feb 27 17:17:50 2014 +0100
@@ -292,7 +292,11 @@
 	      CPUVEC_SETUP_core2;
 	      CPUVEC_SETUP_coreinhm;
 	      CPUVEC_SETUP_coreisbr;
-	      CPUVEC_SETUP_coreihwl;
+	      /* Some Haswells lack BMI2.  Let them appear as Sandybridges for
+		 now.  */
+	      __gmpn_cpuid (dummy_string, 7);
+	      if ((dummy_string[0 + 8 / 8] & (1 << (8 % 8))) != 0)
+		CPUVEC_SETUP_coreihwl;
 	      break;
 	    }
 	  break;
diff -r 8b074a2e0134 -r 07a2dde2c971 mpn/x86_64/fat/fat_entry.asm
--- a/mpn/x86_64/fat/fat_entry.asm	Thu Feb 27 10:43:48 2014 +0100
+++ b/mpn/x86_64/fat/fat_entry.asm	Thu Feb 27 17:17:50 2014 +0100
@@ -3,7 +3,7 @@
 dnl  Contributed to the GNU project by Kevin Ryde (original x86_32 code) and
 dnl  Torbjorn Granlund (port to x86_64)
 
-dnl  Copyright 2003, 2009, 2011-2013 Free Software Foundation, Inc.
+dnl  Copyright 2003, 2009, 2011-2014 Free Software Foundation, Inc.
 
 dnl  This file is part of the GNU MP Library.
 dnl
@@ -183,7 +183,8 @@
 C long __gmpn_cpuid (char dst[12], int id);
 C
 C This is called only 3 times, so just something simple and compact is fine.
-
+C
+C The rcx/ecx zeroing here is needed for the BMI2 check.
 
 define(`rp',  `%rdi')
 define(`idx', `%rsi')
@@ -192,6 +193,7 @@
 	FUNC_ENTRY(2)
 	mov	%rbx, %r8
 	mov	R32(idx), R32(%rax)
+	xor	%ecx, %ecx
 	cpuid
 	mov	%ebx, (rp)
 	mov	%edx, 4(rp)