Test for reliable fpes on Darwin platforms without DARWIN_MODERN_MCONTEXT

The mcontext_t structure changed between Tiger & Leopard and the erts
configure script doesn't take this into account when testing for
reliable floating point exceptions.  HiPE is not enabled when reliable
fpes are not detected.

The PPC test preserves the pre-modern mcontext_t and so builds on Tiger,
but I suspect that PPC/Leopard is broken.  I don't have the header files
to check modern PPC mcontext_t so I haven't changed that part of the test.

1 files changed, 56 insertions, 37 deletions

diff --git a/erts/configure.in b/erts/configure.in
index 895a357023..2797351e45 100644
--- a/erts/configure.in
+++ b/erts/configure.in
@@ -2145,6 +2145,44 @@ if test X${enable_hipe} != Xno; then
   	esac
   fi
 fi
+
+case $ARCH-$OPSYS in
+	amd64-darwin*|x86-darwin*)
+		AC_MSG_CHECKING([For modern (leopard) style mcontext_t])
+		AC_TRY_COMPILE([
+				#include <stdlib.h>
+				#include <sys/types.h>
+				#include <unistd.h>
+				#include <mach/mach.h>
+				#include <pthread.h>
+				#include <machine/signal.h>
+				#include <ucontext.h>
+				],[
+				#if defined(__APPLE__) && defined(__MACH__) && !defined(__DARWIN__)
+				#define __DARWIN__ 1
+				#endif
+
+				#ifndef __DARWIN__
+				#error inpossible
+				#else
+
+				mcontext_t mc = NULL;
+				int x = mc->__fs.__fpu_mxcsr;
+
+				#endif
+				],darwin_mcontext_leopard=yes,
+				darwin_mcontext_leopard=no)
+				if test X"$darwin_mcontext_leopard" = X"yes"; then
+				   AC_DEFINE(DARWIN_MODERN_MCONTEXT,[],[Modern style mcontext_t in MacOSX])
+				   AC_MSG_RESULT(yes)
+				else
+				   AC_MSG_RESULT(no)
+				fi
+		;;
+	*)
+		darwin_mcontext_leopard=no
+		;;
+esac
 if test X${enable_fp_exceptions} = Xauto ; then
    if test X${enable_hipe} = Xyes; then
       enable_fp_exceptions=yes
@@ -2534,6 +2572,7 @@ static void fpe_sig_action(int sig, siginfo_t *si, void *puc)
     regs[PT_FPSCR] = 0x80|0x40|0x10;	/* VE, OE, ZE; not UE or XE */
 #endif
 #elif defined(__DARWIN__)
+#if defined(DARWIN_MODERN_MCONTEXT)
 #if defined(__x86_64__)
     mcontext_t mc = uc->uc_mcontext;
     struct __darwin_x86_float_state64 *fpstate = &mc->__fs;
@@ -2549,6 +2588,23 @@ static void fpe_sig_action(int sig, siginfo_t *si, void *puc)
     mc->ss.srr0 += 4;
     mc->fs.fpscr = 0x80|0x40|0x10;
 #endif
+#else
+#if defined(__x86_64__)
+    mcontext_t mc = uc->uc_mcontext;
+    struct x86_float_state64_t *fpstate = &mc->fs;
+    fpstate->fpu_mxcsr = 0x1F80;
+    *(unsigned short *)&fpstate->fpu_fsw &= ~0xFF;
+#elif defined(__i386__)
+    mcontext_t mc = uc->uc_mcontext;
+    x86_float_state32_t	*fpstate = &mc->fs;
+    fpstate->fpu_mxcsr = 0x1F80;
+    *(unsigned short *)&fpstate->fpu_fsw &= ~0xFF;
+#elif defined(__ppc__)
+    mcontext_t mc = uc->uc_mcontext;
+    mc->ss.srr0 += 4;
+    mc->fs.fpscr = 0x80|0x40|0x10;
+#endif
+#endif
 #elif defined(__FreeBSD__) && defined(__x86_64__)
     mcontext_t *mc = &uc->uc_mcontext;
     struct savefpu *savefpu = (struct savefpu*)&mc->mc_fpstate;
@@ -2655,43 +2711,6 @@ int main(int argc, const char **argv)
     fi
 fi	
 
-case $ARCH-$OPSYS in
-	amd64-darwin*|x86-darwin*)
-		AC_MSG_CHECKING([For modern (leopard) style mcontext_t])
-		AC_TRY_COMPILE([
-				#include <stdlib.h>
-				#include <sys/types.h>
-				#include <unistd.h>
-				#include <mach/mach.h>
-				#include <pthread.h>
-				#include <machine/signal.h>
-				#include <ucontext.h>
-				],[
-				#if defined(__APPLE__) && defined(__MACH__) && !defined(__DARWIN__)
-				#define __DARWIN__ 1
-				#endif
-
-				#ifndef __DARWIN__
-				#error inpossible
-				#else
-
-    				mcontext_t mc = NULL;
-    				int x = mc->__fs.__fpu_mxcsr;
-
-				#endif
-				],darwin_mcontext_leopard=yes,
-				darwin_mcontext_leopard=no)
-				if test X"$darwin_mcontext_leopard" = X"yes"; then
-				   AC_DEFINE(DARWIN_MODERN_MCONTEXT,[],[Modern style mcontext_t in MacOSX])
-				   AC_MSG_RESULT(yes)
-				else
-				   AC_MSG_RESULT(no)
-				fi		
-		;;
-	*)	
-		darwin_mcontext_leopard=no
-		;;
-esac