From: H.J. Lu <hjl.tools@gmail.com>
Date: Wed, 26 Aug 2015 14:55:42 +0000 (-0700)
Subject: Don't disable SSE in x86-64 ld.so
X-Git-Tag: glibc-2.23~556
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=38d22f9f48a84b441c5777aff103f5b980243b5f;p=thirdparty%2Fglibc.git

Don't disable SSE in x86-64 ld.so

Since x86-64 ld.so preserves vector registers now, we can use SSE in
x86-64 ld.so.  We should run tst-ld-sse-use.sh only on i386.

	* sysdeps/x86/Makefile [$(subdir) == elf] (CFLAGS-.os,
	tests-special, $(objpfx)tst-ld-sse-use.out): Moved to ...
	* sysdeps/i386/Makefile [$(subdir) == elf] (CFLAGS-.os,
	tests-special, $(objpfx)tst-ld-sse-use.out): Here.  Update
	comments.
	* sysdeps/x86_64/Makefile [$(subdir) == elf] (CFLAGS-.os): Add
	-mno-mmx for $(all-rtld-routines).
	* sysdeps/x86/tst-ld-sse-use.sh: Moved to ...
	* sysdeps/i386/tst-ld-sse-use.sh: Here.  Replace x86-64 with
	i386.
---

diff --git a/ChangeLog b/ChangeLog
index 72255512a57..478a0096579 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,16 @@
+2015-08-26  H.J. Lu  <hongjiu.lu@intel.com>
+
+	* sysdeps/x86/Makefile [$(subdir) == elf] (CFLAGS-.os,
+	tests-special, $(objpfx)tst-ld-sse-use.out): Moved to ...
+	* sysdeps/i386/Makefile [$(subdir) == elf] (CFLAGS-.os,
+	tests-special, $(objpfx)tst-ld-sse-use.out): Here.  Update
+	comments.
+	* sysdeps/x86_64/Makefile [$(subdir) == elf] (CFLAGS-.os): Add
+	-mno-mmx for $(all-rtld-routines).
+	* sysdeps/x86/tst-ld-sse-use.sh: Moved to ...
+	* sysdeps/i386/tst-ld-sse-use.sh: Here.  Replace x86-64 with
+	i386.
+
 2015-08-26  Stefan Liebler  <stli@linux.vnet.ibm.com>
 
 	* sysdeps/generic/unwind.h
diff --git a/sysdeps/i386/Makefile b/sysdeps/i386/Makefile
index 717d8e74544..168512fc327 100644
--- a/sysdeps/i386/Makefile
+++ b/sysdeps/i386/Makefile
@@ -83,3 +83,17 @@ endif
 ifeq ($(subdir),csu)
 gen-as-const-headers += tlsdesc.sym
 endif
+
+ifeq ($(subdir),elf)
+# Make sure no code in ld.so uses mm/xmm/ymm/zmm registers on i386 since
+# the first 3 mm/xmm/ymm/zmm registers are used to pass vector parameters
+# which must be preserved.
+CFLAGS-.os += $(if $(filter $(@F),$(patsubst %,%.os,$(all-rtld-routines))),\
+		   -mno-sse -mno-mmx)
+
+tests-special += $(objpfx)tst-ld-sse-use.out
+$(objpfx)tst-ld-sse-use.out: ../sysdeps/i386/tst-ld-sse-use.sh $(objpfx)ld.so
+	@echo "Checking ld.so for SSE register use.  This will take a few seconds..."
+	$(BASH) $< $(objpfx) '$(NM)' '$(OBJDUMP)' '$(READELF)' > $@; \
+	$(evaluate-test)
+endif
diff --git a/sysdeps/x86/tst-ld-sse-use.sh b/sysdeps/i386/tst-ld-sse-use.sh
similarity index 97%
rename from sysdeps/x86/tst-ld-sse-use.sh
rename to sysdeps/i386/tst-ld-sse-use.sh
index 839de18546d..85a06510b99 100755
--- a/sysdeps/x86/tst-ld-sse-use.sh
+++ b/sysdeps/i386/tst-ld-sse-use.sh
@@ -1,5 +1,5 @@
 #! /bin/bash
-# Make sure no code in ld.so uses xmm/ymm/zmm registers on x86-64.
+# Make sure no code in ld.so uses xmm/ymm/zmm registers on i386.
 # Copyright (C) 2009-2015 Free Software Foundation, Inc.
 # This file is part of the GNU C Library.
 
diff --git a/sysdeps/x86/Makefile b/sysdeps/x86/Makefile
index c262fdf4877..0de4f42168c 100644
--- a/sysdeps/x86/Makefile
+++ b/sysdeps/x86/Makefile
@@ -1,14 +1,3 @@
-ifeq ($(subdir),elf)
-CFLAGS-.os += $(if $(filter $(@F),$(patsubst %,%.os,$(all-rtld-routines))),\
-		   -mno-sse -mno-mmx)
-
-tests-special += $(objpfx)tst-ld-sse-use.out
-$(objpfx)tst-ld-sse-use.out: ../sysdeps/x86/tst-ld-sse-use.sh $(objpfx)ld.so
-	@echo "Checking ld.so for SSE register use.  This will take a few seconds..."
-	$(BASH) $< $(objpfx) '$(NM)' '$(OBJDUMP)' '$(READELF)' > $@; \
-	$(evaluate-test)
-endif
-
 ifeq ($(subdir),csu)
 gen-as-const-headers += cpu-features-offsets.sym rtld-global-offsets.sym
 endif
diff --git a/sysdeps/x86_64/Makefile b/sysdeps/x86_64/Makefile
index e50bcadf510..6c283187a86 100644
--- a/sysdeps/x86_64/Makefile
+++ b/sysdeps/x86_64/Makefile
@@ -19,6 +19,10 @@ gen-as-const-headers += locale-defines.sym
 endif
 
 ifeq ($(subdir),elf)
+# There is no good reason to use MMX in x86-64 ld.so with GCC.
+CFLAGS-.os += $(if $(filter $(@F),$(patsubst %,%.os,$(all-rtld-routines))),\
+		   -mno-mmx)
+
 sysdep-dl-routines += tlsdesc dl-tlsdesc
 
 tests += ifuncmain8