Patch 6 of 7, improve PPC HW capabiltiy checking.

The patch was submitted by Will Schmidt  (will_schmidt@vnet.ibm.com).

Rework hwcap checking in configure.ac.  This adds and swizzles
some of the capability checking as found in configure.ac.
This cleans up some corner cases where capabilities were assumed
based on compiler features, but not supported by the platform.
- clean up vsx kludge, and remove associated comment.
- check assorted capabilities against the hwcap values, including
  altivec, vsx, dfp, htm, ISA_2_0* .

Bugzilla 34979

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@15424

diff --git a/configure.ac b/configure.ac
index deb1acd54e1744df14e3d4f818f929acc62819cf..467d618f85086c61429f5b07cb61e670cc09b9ce 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -1285,16 +1285,38 @@ AC_DEFUN([AC_HWCAP_CONTAINS_FLAG],[
 ])
 
 # gather hardware capabilities. (hardware/kernel/libc)
+AC_HWCAP_CONTAINS_FLAG([altivec],[HWCAP_HAS_ALTIVEC])
+AC_HWCAP_CONTAINS_FLAG([vsx],[HWCAP_HAS_VSX])
+AC_HWCAP_CONTAINS_FLAG([dfp],[HWCAP_HAS_DFP])
+AC_HWCAP_CONTAINS_FLAG([arch_2_05],[HWCAP_HAS_ISA_2_05])
+AC_HWCAP_CONTAINS_FLAG([arch_2_06],[HWCAP_HAS_ISA_2_06])
+AC_HWCAP_CONTAINS_FLAG([arch_2_07],[HWCAP_HAS_ISA_2_07])
 AC_HWCAP_CONTAINS_FLAG([htm],[HWCAP_HAS_HTM])
 
+# ISA Levels
+AM_CONDITIONAL(HAS_ISA_2_05, [test x$HWCAP_HAS_ISA_2_05 = xyes])
+AM_CONDITIONAL(HAS_ISA_2_06, [test x$HWCAP_HAS_ISA_2_06 = xyes])
+# compiler support for isa 2.07 level instructions
+AC_MSG_CHECKING([that assembler knows ISA 2.07 instructions ])
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+]], [[
+  __asm__ __volatile__("mtvsrd 1,2 ");
+]])], [
+ac_asm_have_isa_2_07=yes
+AC_MSG_RESULT([yes])
+], [
+ac_asm_have_isa_2_07=no
+AC_MSG_RESULT([no])
+])
+AM_CONDITIONAL(HAS_ISA_2_07, [test x$ac_asm_have_isa_2_07 = xyes \
+                               -a x$HWCAP_HAS_ISA_2_07 = xyes])
+
+# altivec (vsx) support.
 # does this compiler support -maltivec and does it have the include file
 # <altivec.h> ?
-
-AC_MSG_CHECKING([for Altivec])
-
+AC_MSG_CHECKING([for Altivec support in the compiler ])
 safe_CFLAGS=$CFLAGS
 CFLAGS="-maltivec -Werror"
-
 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
 #include <altivec.h>
 ]], [[
@@ -1309,42 +1331,48 @@ ac_have_altivec=no
 AC_MSG_RESULT([no])
 ])
 CFLAGS=$safe_CFLAGS
-
-AM_CONDITIONAL([HAS_ALTIVEC], [test x$ac_have_altivec = xyes])
-
+AM_CONDITIONAL([HAS_ALTIVEC], [test x$ac_have_altivec = xyes \
+                                 -a x$HWCAP_HAS_ALTIVEC = xyes])
 
 # Check that both: the compiler supports -mvsx and that the assembler
 # understands VSX instructions.  If either of those doesn't work,
-# conclude that we can't do VSX.  NOTE: basically this is a kludge
-# in that it conflates two things that should be separate -- whether
-# the compiler understands the flag vs whether the assembler 
-# understands the opcodes.  This really ought to be cleaned up
-# and done properly, like it is for x86/x86_64.
-
-AC_MSG_CHECKING([for VSX])
-
+# conclude that we can't do VSX.
+AC_MSG_CHECKING([for VSX compiler flag support])
 safe_CFLAGS=$CFLAGS
 CFLAGS="-mvsx -Werror"
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+]], [[
+]])], [
+ac_compiler_supports_vsx_flag=yes
+AC_MSG_RESULT([yes])
+], [
+ac_compiler_supports_vsx_flag=no
+AC_MSG_RESULT([no])
+])
+CFLAGS=$safe_CFLAGS
 
+AC_MSG_CHECKING([for VSX support in the assembler ])
+safe_CFLAGS=$CFLAGS
+CFLAGS="-mvsx -Werror"
 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
 #include <altivec.h>
 ]], [[
   vector unsigned int v;
   __asm__ __volatile__("xsmaddadp 32, 32, 33" ::: "memory","cc");
 ]])], [
-ac_have_vsx=yes
+ac_compiler_supports_vsx=yes
 AC_MSG_RESULT([yes])
 ], [
-ac_have_vsx=no
+ac_compiler_supports_vsx=no
 AC_MSG_RESULT([no])
 ])
 CFLAGS=$safe_CFLAGS
+AM_CONDITIONAL([HAS_VSX], [test x$ac_compiler_supports_vsx_flag = xyes \
+                             -a x$ac_compiler_supports_vsx = xyes \
+                             -a x$HWCAP_HAS_VSX = xyes ])
 
-AM_CONDITIONAL(HAS_VSX, test x$ac_have_vsx = xyes)
-
-
+# DFP (Decimal Float)
 AC_MSG_CHECKING([that assembler knows DFP])
-
 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
 ]], [[
   __asm__ __volatile__("dadd 1, 2, 3");
@@ -1356,8 +1384,6 @@ AC_MSG_RESULT([yes])
 ac_asm_have_dfp=no
 AC_MSG_RESULT([no])
 ])
-
-
 AC_MSG_CHECKING([that compiler knows -mhard-dfp switch])
 safe_CFLAGS=$CFLAGS
 CFLAGS="-mhard-dfp -Werror"
@@ -1366,47 +1392,31 @@ AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
   __asm__ __volatile__("dadd 1, 2, 3");
   __asm__ __volatile__("dcffix 1, 2");
 ]])], [
-ac_gcc_have_dfp=yes
+ac_compiler_have_dfp=yes
 AC_MSG_RESULT([yes])
 ], [
-ac_gcc_have_dfp=no
+ac_compiler_have_dfp=no
 AC_MSG_RESULT([no])
 ])
-
 CFLAGS=$safe_CFLAGS
-
-AM_CONDITIONAL(HAS_DFP, test x$ac_asm_have_dfp = xyes -a x$ac_gcc_have_dfp = xyes)
-
+AM_CONDITIONAL(HAS_DFP, test x$ac_asm_have_dfp = xyes \
+                          -a x$ac_compiler_have_dfp = xyes \
+                          -a x$HWCAP_HAS_DFP = xyes )
 
 AC_MSG_CHECKING([that compiler knows DFP datatypes])
 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
 ]], [[
   _Decimal64 x = 0.0DD;
 ]])], [
-ac_gcc_have_dfp_type=yes
-AC_MSG_RESULT([yes])
-], [
-ac_gcc_have_dfp_type=no
-AC_MSG_RESULT([no])
-])
-
-AM_CONDITIONAL(BUILD_DFP_TESTS, test x$ac_gcc_have_dfp_type = xyes)
-
-# isa 2.07 checking
-AC_MSG_CHECKING([that assembler knows ISA 2.07 ])
-
-AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
-]], [[
-  __asm__ __volatile__("mtvsrd 1,2 ");
-]])], [
-ac_asm_have_isa_2_07=yes
+ac_compiler_have_dfp_type=yes
 AC_MSG_RESULT([yes])
 ], [
-ac_asm_have_isa_2_07=no
+ac_compiler_have_dfp_type=no
 AC_MSG_RESULT([no])
 ])
+AM_CONDITIONAL(BUILD_DFP_TESTS, test x$ac_compiler_have_dfp_type = xyes \
+                                  -a xHWCAP_$HAS_DFP = xyes )
 
-AM_CONDITIONAL(HAS_ISA_2_07, test x$ac_asm_have_isa_2_07 = xyes)
 
 # HTM (Hardware Transactional Memory)
 AC_MSG_CHECKING([if compiler accepts the -mhtm flag])