Enable building libitm with Intel CET

libitm/
	* Makefile.in: Regenerate.
	* acinclude.m4: Add enable.m4 and cet.m4.
	* config/x86/sjlj.S: Include cet.h.
	(_ITM_beginTransaction): Add _CET_ENDBR.
	Save Shadow Stack pointer.
	(GTM_longjmp): Add _CET_ENDBR. Restore Shadow Stack pointer.
	* config/x86/target.h (struct gtm_jmpbuf):
	Add new field for Shadow Stack pointer.
	* configure: Regenerate.
	* configure.ac: Set CET_FLAGS. Update XCFLAGS.
	* configure.ac: Update libtool_VERSION for x86.
	* testsuite/Makefile.in: Regenerate.



git-svn-id: https://gcc.gnu.org/svn/gcc/trunk@254908 138bc75d-0d04-0410-961f-82ee72b054a4

7 files changed, 163 insertions, 4 deletions

diff --git a/libitm/ChangeLog b/libitm/ChangeLog
index 196ac9a1ab2..fb2e9493224 100644
--- a/libitm/ChangeLog
+++ b/libitm/ChangeLog
@@ -1,5 +1,20 @@
 2017-11-17  Igor Tsimbalist  <igor.v.tsimbalist@intel.com>
 
+	* Makefile.in: Regenerate.
+	* acinclude.m4: Add enable.m4 and cet.m4.
+	* config/x86/sjlj.S: Include cet.h.
+	(_ITM_beginTransaction): Add _CET_ENDBR.
+	Save Shadow Stack pointer.
+	(GTM_longjmp): Add _CET_ENDBR. Restore Shadow Stack pointer.
+	* config/x86/target.h (struct gtm_jmpbuf):
+	Add new field for Shadow Stack pointer.
+	* configure: Regenerate.
+	* configure.ac: Set CET_FLAGS. Update XCFLAGS.
+	* configure.ac: Update libtool_VERSION for x86.
+	* testsuite/Makefile.in: Regenerate.
+
+2017-11-17  Igor Tsimbalist  <igor.v.tsimbalist@intel.com>
+
 	* libitm/config/x86/target.h: Add new field (ssp).
 	* libitm/config/x86/sjlj.S: Change offsets.
 
diff --git a/libitm/Makefile.in b/libitm/Makefile.in
index bd16ce0cfb8..703f279efdd 100644
--- a/libitm/Makefile.in
+++ b/libitm/Makefile.in
@@ -78,7 +78,7 @@ am__aclocal_m4_deps = $(top_srcdir)/../config/acx.m4 \
 	$(top_srcdir)/../ltoptions.m4 $(top_srcdir)/../ltsugar.m4 \
 	$(top_srcdir)/../ltversion.m4 $(top_srcdir)/../lt~obsolete.m4 \
 	$(top_srcdir)/acinclude.m4 $(top_srcdir)/../libtool.m4 \
-	$(top_srcdir)/configure.ac
+	$(top_srcdir)/../config/cet.m4 $(top_srcdir)/configure.ac
 am__configure_deps = $(am__aclocal_m4_deps) $(CONFIGURE_DEPENDENCIES) \
 	$(ACLOCAL_M4)
 am__CONFIG_DISTCLEAN_FILES = config.status config.cache config.log \
diff --git a/libitm/acinclude.m4 b/libitm/acinclude.m4
index c81b3e909a7..cd8150ce95f 100644
--- a/libitm/acinclude.m4
+++ b/libitm/acinclude.m4
@@ -149,6 +149,7 @@ s390*)
 esac])
 
 sinclude(../libtool.m4)
+sinclude(../config/cet.m4)
 dnl The lines below arrange for aclocal not to bring an installed
 dnl libtool.m4 into aclocal.m4, while still arranging for automake to
 dnl add a definition of LIBTOOL to Makefile.in.
diff --git a/libitm/config/x86/sjlj.S b/libitm/config/x86/sjlj.S
index 7de417ca101..006e44db0eb 100644
--- a/libitm/config/x86/sjlj.S
+++ b/libitm/config/x86/sjlj.S
@@ -25,6 +25,7 @@
 
 #include "asmcfi.h"
 #include "config.h"
+#include "cet.h"
 
 #define CONCAT1(a, b) CONCAT2(a, b)
 #define CONCAT2(a, b) a ## b
@@ -73,6 +74,7 @@
 
 SYM(_ITM_beginTransaction):
 	cfi_startproc
+	_CET_ENDBR
 #ifdef __x86_64__
 #ifdef HAVE_AS_RTM
 	/* Custom HTM fast path.  We start the HW transaction here and let
@@ -138,6 +140,10 @@ SYM(_ITM_beginTransaction):
 	movq	%r14, -32(%rax)
 	movq	%r15, -24(%rax)
 	xorq	%rdx, %rdx
+	/* Save zero or shadow stack pointer in the new field.  */
+#if defined(__SHSTK__) && defined(__CET__)
+	rdsspq	%rdx
+#endif
 	movq	%rdx, -16(%rax)
 	leaq	-72(%rax), %rsi
 	call	SYM(GTM_begin_transaction)
@@ -170,6 +176,10 @@ SYM(_ITM_beginTransaction):
 	movl	%edi, 16(%esp)
 	movl	%ebp, 20(%esp)
 	xorl	%edx, %edx
+	/* Save zero or shadow stack pointer in the new field.  */
+#if defined(__SHSTK__) && defined(__CET__)
+	rdsspd	%edx
+#endif
 	movl	%edx, 24(%esp)
 	leal	4(%esp), %edx
 #if defined HAVE_ATTRIBUTE_VISIBILITY || !defined __PIC__
@@ -197,6 +207,7 @@ SYM(_ITM_beginTransaction):
 
 SYM(GTM_longjmp):
 	cfi_startproc
+	_CET_ENDBR
 #ifdef __x86_64__
 	movq	(%rsi), %rcx
 	movq	8(%rsi), %rbx
@@ -210,6 +221,33 @@ SYM(GTM_longjmp):
 	cfi_offset(%rip, 64)
 	cfi_register(%rsp, %rcx)
 	movq	%rcx, %rsp
+#if defined(__SHSTK__) && defined(__CET__)
+	/* Check if Shadow Stack is enabled.  */
+	xorq	%rcx, %rcx
+	rdsspq	%rcx
+	testq	%rcx, %rcx
+	je	.L1
+	/* Calculate number of frames to skip.  */
+	subq	56(%rsi), %rcx
+	negq	%rcx
+	shrq	$3, %rcx
+	incq	%rcx
+	/* If # of frames is greater 255 then loop
+	   and adjust.  */
+	cmpq	$255, %rcx
+	jle	.L3
+	movl	$255, %edi
+	.p2align 4,,10
+	.p2align 3
+.L4:
+	incsspq	%rdi
+	subq	$255, %rcx
+	cmpq	$255, %rcx
+	jg	.L4
+.L3:
+	incsspq	%rcx
+.L1:
+#endif
 	jmp	*64(%rsi)
 #else
 	movl	(%edx), %ecx
@@ -221,6 +259,35 @@ SYM(GTM_longjmp):
 	cfi_offset(%eip, 24)
 	cfi_register(%esp, %ecx)
 	movl	%ecx, %esp
+#if defined(__SHSTK__) && defined(__CET__)
+	/* Check if Shadow Stack is enabled.  */
+	xorl	%ecx, %ecx
+	rdsspd	%ecx
+	testl	%ecx, %ecx
+	je	.L1
+	/* Calculate # of frames to skip.  */
+	subl	20(%edx), %ecx
+	negl	%ecx
+	shrl	$2, %ecx
+	incl	%ecx
+	/* If # of frames is greater 255 then loop
+	   and adjust.  */
+	cmpl	$255, %ecx
+	jle	.L3
+	pushl	%eax
+	movl	$255, %eax
+	.p2align 4,,10
+	.p2align 3
+.L4:
+	incsspd	%eax
+	subl	$255, %ecx
+	cmpl	$255, %ecx
+	jg	.L4
+	popl	%eax
+.L3:
+	incsspd	%ecx
+.L1:
+#endif
 	jmp	*24(%edx)
 #endif
 	cfi_endproc
diff --git a/libitm/configure b/libitm/configure
index 775f370fbb5..d061c8c2659 100644
--- a/libitm/configure
+++ b/libitm/configure
@@ -777,6 +777,7 @@ enable_maintainer_mode
 enable_linux_futex
 enable_tls
 enable_symvers
+enable_cet
 with_gcc_major_version_only
 '
       ac_precious_vars='build_alias
@@ -1426,6 +1427,8 @@ Optional Features:
   --enable-tls            Use thread-local storage [default=yes]
   --enable-symvers=STYLE  enables symbol versioning of the shared library
                           [default=yes]
+  --enable-cet            enable Intel CET in target libraries
+                          [default=default]
 
 Optional Packages:
   --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]
@@ -11794,7 +11797,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11797 "configure"
+#line 11800 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11900,7 +11903,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11903 "configure"
+#line 11906 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -17586,6 +17589,75 @@ fi
 
 XCFLAGS="$XCFLAGS $XPCFLAGS"
 
+# Add CET specific flags if CET is enabled
+ # Check whether --enable-cet was given.
+if test "${enable_cet+set}" = set; then :
+  enableval=$enable_cet;
+      case "$enableval" in
+       yes|no|default) ;;
+       *) as_fn_error "Unknown argument to enable/disable cet" "$LINENO" 5 ;;
+                          esac
+
+else
+  enable_cet=default
+fi
+
+
+case "$host" in
+  i[34567]86-*-linux* | x86_64-*-linux*)
+    case "$enable_cet" in
+      default)
+	# Check if assembler supports CET.
+	cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+asm ("setssbsy");
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  enable_cet=yes
+else
+  enable_cet=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+	;;
+      yes)
+	# Check if assembler supports CET.
+	cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+asm ("setssbsy");
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+
+else
+  as_fn_error "assembler with CET support is required for --enable-cet" "$LINENO" 5
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+	;;
+    esac
+    ;;
+  *)
+    enable_cet=no
+    ;;
+esac
+if test x$enable_cet = xyes; then
+  CET_FLAGS="-fcf-protection -mcet"
+fi
+
+XCFLAGS="$XCFLAGS $CET_FLAGS"
+
 
 
 
diff --git a/libitm/configure.ac b/libitm/configure.ac
index c5ecd394a43..ad77fcae2a6 100644
--- a/libitm/configure.ac
+++ b/libitm/configure.ac
@@ -260,6 +260,10 @@ fi
 
 XCFLAGS="$XCFLAGS $XPCFLAGS"
 
+# Add CET specific flags if CET is enabled
+GCC_CET_FLAGS(CET_FLAGS)
+XCFLAGS="$XCFLAGS $CET_FLAGS"
+
 AC_SUBST(config_path)
 AC_SUBST(XCFLAGS)
 AC_SUBST(XLDFLAGS)
diff --git a/libitm/testsuite/Makefile.in b/libitm/testsuite/Makefile.in
index eb9e992279d..34dcdd2dae0 100644
--- a/libitm/testsuite/Makefile.in
+++ b/libitm/testsuite/Makefile.in
@@ -70,7 +70,7 @@ am__aclocal_m4_deps = $(top_srcdir)/../config/acx.m4 \
 	$(top_srcdir)/../ltoptions.m4 $(top_srcdir)/../ltsugar.m4 \
 	$(top_srcdir)/../ltversion.m4 $(top_srcdir)/../lt~obsolete.m4 \
 	$(top_srcdir)/acinclude.m4 $(top_srcdir)/../libtool.m4 \
-	$(top_srcdir)/configure.ac
+	$(top_srcdir)/../config/cet.m4 $(top_srcdir)/configure.ac
 am__configure_deps = $(am__aclocal_m4_deps) $(CONFIGURE_DEPENDENCIES) \
 	$(ACLOCAL_M4)
 mkinstalldirs = $(SHELL) $(top_srcdir)/../mkinstalldirs