re PR go/78978 (runtime/pprof FAILs on Solaris 2/x86)

	PR go/78978
    libgo: build with -Wa,-nH if possible on Solaris
    
    By default the Solaris assembler records the required hardware
    capability in the object file.  This means that the AES hashing code
    breaks on systems that do not support AES, even though the code uses a
    runtime check to only actually invoke the AES instructions on systems
    that support it.  An earlier fix for the problem only fixed the shared
    library, not the static libgo.a.  Fix the problem for real by using an
    assembler option to not record the hardware capability.
    
    For GCC PR 78978.
    
    Patch by Rainer Orth.
    
    Reviewed-on: https://go-review.googlesource.com/34910

From-SVN: r244165

5 files changed, 36 insertions, 50 deletions

diff --git a/libgo/Makefile.am b/libgo/Makefile.am
index 1f5a021..93eaa9f 100644
--- a/libgo/Makefile.am
+++ b/libgo/Makefile.am
@@ -42,14 +42,12 @@ ACLOCAL_AMFLAGS = -I ./config -I ../config
 
 AM_CFLAGS = -fexceptions -fnon-call-exceptions -fplan9-extensions \
 	$(SPLIT_STACK) $(WARN_CFLAGS) \
-	$(STRINGOPS_FLAG) $(OSCFLAGS) \
+	$(STRINGOPS_FLAG) $(HWCAP_CFLAGS) $(OSCFLAGS) \
 	-I $(srcdir)/../libgcc -I $(srcdir)/../libbacktrace \
 	-I $(MULTIBUILDTOP)../../gcc/include
 
-AM_LDFLAGS = $(HWCAP_LDFLAGS)
-
 if USING_SPLIT_STACK
-AM_LDFLAGS += -XCClinker $(SPLIT_STACK)
+AM_LDFLAGS = -XCClinker $(SPLIT_STACK)
 endif
 
 # Multilib support.
diff --git a/libgo/Makefile.in b/libgo/Makefile.in
index a161fd7..424e41b 100644
--- a/libgo/Makefile.in
+++ b/libgo/Makefile.in
@@ -62,9 +62,8 @@ POST_UNINSTALL = :
 build_triplet = @build@
 host_triplet = @host@
 target_triplet = @target@
-@USING_SPLIT_STACK_TRUE@am__append_1 = -XCClinker $(SPLIT_STACK)
-@GOC_IS_LLGO_TRUE@am__append_2 = libgo-llgo.la libgobegin-llgo.a
-@GOC_IS_LLGO_FALSE@am__append_3 = libgo.la libgobegin.a
+@GOC_IS_LLGO_TRUE@am__append_1 = libgo-llgo.la libgobegin-llgo.a
+@GOC_IS_LLGO_FALSE@am__append_2 = libgo.la libgobegin.a
 subdir = .
 DIST_COMMON = README $(srcdir)/Makefile.in $(srcdir)/Makefile.am \
 	$(top_srcdir)/configure $(am__configure_deps) \
@@ -321,7 +320,7 @@ GO_SPLIT_STACK = @GO_SPLIT_STACK@
 GO_SYSCALL_OS_ARCH_FILE = @GO_SYSCALL_OS_ARCH_FILE@
 GO_SYSCALL_OS_FILE = @GO_SYSCALL_OS_FILE@
 GREP = @GREP@
-HWCAP_LDFLAGS = @HWCAP_LDFLAGS@
+HWCAP_CFLAGS = @HWCAP_CFLAGS@
 INSTALL = @INSTALL@
 INSTALL_DATA = @INSTALL_DATA@
 INSTALL_PROGRAM = @INSTALL_PROGRAM@
@@ -459,11 +458,11 @@ AM_CPPFLAGS = -I $(srcdir)/runtime $(LIBFFIINCS) $(PTHREAD_CFLAGS)
 ACLOCAL_AMFLAGS = -I ./config -I ../config
 AM_CFLAGS = -fexceptions -fnon-call-exceptions -fplan9-extensions \
 	$(SPLIT_STACK) $(WARN_CFLAGS) \
-	$(STRINGOPS_FLAG) $(OSCFLAGS) \
+	$(STRINGOPS_FLAG) $(HWCAP_CFLAGS) $(OSCFLAGS) \
 	-I $(srcdir)/../libgcc -I $(srcdir)/../libbacktrace \
 	-I $(MULTIBUILDTOP)../../gcc/include
 
-AM_LDFLAGS = $(HWCAP_LDFLAGS) $(am__append_1)
+@USING_SPLIT_STACK_TRUE@AM_LDFLAGS = -XCClinker $(SPLIT_STACK)
 
 # Multilib support.
 MAKEOVERRIDES = 
@@ -1120,7 +1119,7 @@ CHECK_DEPS = $(toolexeclibgo_DATA) $(toolexeclibgoarchive_DATA) \
 	$(toolexeclibgorpc_DATA) $(toolexeclibgoruntime_DATA) \
 	$(toolexeclibgosync_DATA) $(toolexeclibgotesting_DATA) \
 	$(toolexeclibgotext_DATA) $(toolexeclibgotexttemplate_DATA) \
-	$(toolexeclibgounicode_DATA) $(am__append_2) $(am__append_3)
+	$(toolexeclibgounicode_DATA) $(am__append_1) $(am__append_2)
 
 # Pass -ffp-contract=off, or 386-specific options, when building the
 # math package.  MATH_FLAG is defined in configure.ac.
diff --git a/libgo/configure b/libgo/configure
index 2cd3908..06532d3 100755
--- a/libgo/configure
+++ b/libgo/configure
@@ -624,9 +624,7 @@ GO_SPLIT_STACK
 USING_SPLIT_STACK_FALSE
 USING_SPLIT_STACK_TRUE
 SPLIT_STACK
-HAVE_HWCAP_FALSE
-HAVE_HWCAP_TRUE
-HWCAP_LDFLAGS
+HWCAP_CFLAGS
 OSCFLAGS
 GO_SYSCALL_OS_ARCH_FILE
 GO_SYSCALL_OS_FILE
@@ -11106,7 +11104,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11109 "configure"
+#line 11107 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11212,7 +11210,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11215 "configure"
+#line 11213 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -13912,15 +13910,18 @@ esac
 
 
 
-  test -z "$HWCAP_LDFLAGS" && HWCAP_LDFLAGS=''
+  test -z "$HWCAP_CFLAGS" && HWCAP_CFLAGS=''
 
+  # Restrict the test to Solaris, other assemblers (e.g. AIX as) have -nH
+  # with a different meaning.
+  case ${target_os} in
+    solaris2*)
+      ac_save_CFLAGS="$CFLAGS"
+      CFLAGS="$CFLAGS -Wa,-nH"
 
-  ac_save_LDFLAGS="$LDFLAGS"
-  LDFLAGS="$LFLAGS -mclear-hwcap"
-
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -mclear-hwcap" >&5
-$as_echo_n "checking for -mclear-hwcap... " >&6; }
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+      { $as_echo "$as_me:${as_lineno-$LINENO}: checking for as that supports -Wa,-nH" >&5
+$as_echo_n "checking for as that supports -Wa,-nH... " >&6; }
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
@@ -13931,31 +13932,23 @@ return 0;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
-  ac_hwcap_ldflags=yes
+if ac_fn_c_try_compile "$LINENO"; then :
+  ac_hwcap_flags=yes
 else
-  ac_hwcap_ldflags=no
+  ac_hwcap_flags=no
 fi
-rm -f core conftest.err conftest.$ac_objext \
-    conftest$ac_exeext conftest.$ac_ext
-  if test "$ac_hwcap_ldflags" = "yes"; then
-    HWCAP_LDFLAGS="-mclear-hwcap $HWCAP_LDFLAGS"
-  fi
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_hwcap_ldflags" >&5
-$as_echo "$ac_hwcap_ldflags" >&6; }
-
-  LDFLAGS="$ac_save_LDFLAGS"
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+      if test "$ac_hwcap_flags" = "yes"; then
+	HWCAP_CFLAGS="-Wa,-nH $HWCAP_CFLAGS"
+      fi
+      { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_hwcap_flags" >&5
+$as_echo "$ac_hwcap_flags" >&6; }
 
+      CFLAGS="$ac_save_CFLAGS"
+      ;;
+  esac
 
 
-   if test $ac_hwcap_ldflags != no; then
-  HAVE_HWCAP_TRUE=
-  HAVE_HWCAP_FALSE='#'
-else
-  HAVE_HWCAP_TRUE='#'
-  HAVE_HWCAP_FALSE=
-fi
-
 
 
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether -fsplit-stack is supported" >&5
@@ -15764,10 +15757,6 @@ if test -z "${LIBGO_IS_BSD_TRUE}" && test -z "${LIBGO_IS_BSD_FALSE}"; then
   as_fn_error "conditional \"LIBGO_IS_BSD\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
 fi
-if test -z "${HAVE_HWCAP_TRUE}" && test -z "${HAVE_HWCAP_FALSE}"; then
-  as_fn_error "conditional \"HAVE_HWCAP\" was never defined.
-Usually this means the macro was only invoked conditionally." "$LINENO" 5
-fi
 if test -z "${USING_SPLIT_STACK_TRUE}" && test -z "${USING_SPLIT_STACK_FALSE}"; then
   as_fn_error "conditional \"USING_SPLIT_STACK\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
diff --git a/libgo/configure.ac b/libgo/configure.ac
index a326730..6deafda 100644
--- a/libgo/configure.ac
+++ b/libgo/configure.ac
@@ -421,8 +421,8 @@ case "$target" in
 esac
 AC_SUBST(OSCFLAGS)
 
-dnl Check linker hardware capability support.
-GCC_CHECK_LINKER_HWCAP
+dnl Check if assembler supports disabling hardware capability support.
+GCC_CHECK_ASSEMBLER_HWCAP
 
 dnl Use -fsplit-stack when compiling C code if available.
 AC_CACHE_CHECK([whether -fsplit-stack is supported],
diff --git a/libgo/testsuite/Makefile.in b/libgo/testsuite/Makefile.in
index f059021..79da1c9 100644
--- a/libgo/testsuite/Makefile.in
+++ b/libgo/testsuite/Makefile.in
@@ -124,7 +124,7 @@ GO_SPLIT_STACK = @GO_SPLIT_STACK@
 GO_SYSCALL_OS_ARCH_FILE = @GO_SYSCALL_OS_ARCH_FILE@
 GO_SYSCALL_OS_FILE = @GO_SYSCALL_OS_FILE@
 GREP = @GREP@
-HWCAP_LDFLAGS = @HWCAP_LDFLAGS@
+HWCAP_CFLAGS = @HWCAP_CFLAGS@
 INSTALL = @INSTALL@
 INSTALL_DATA = @INSTALL_DATA@
 INSTALL_PROGRAM = @INSTALL_PROGRAM@