2007-04-30 Steven Munroe <sjmunroe@us.ibm.com>

            Peter Bergner  <bergner@us.ibm.com>

	* sysdeps/powerpc/bits/fenv.h: Declare __fe_mask_env extern.
	Define FE_NOMASK_ENV as FE_EANBLED_ENV.  Define FE_MASK_ENV.
	* sysdeps/powerpc/fpu/Makefile: Add fe_mask to libm-support.
	* sysdeps/powerpc/fpu/fe_mask.c: New file.
	* sysdeps/powerpc/fpu/fe_nomask.c: Correct comment.
	* sysdeps/powerpc/fpu/fedisblxcpt.c (fedisableexcept):
	Call __fe_mask_env() if all FP exceptions disabled.
	* sysdeps/powerpc/fpu/feholdexcpt.c (feholdexcept): Copy high 32-bits
	from old FPSCR to new fenv to propagate DFP rounding modes.
	Call __fe_mask_env() if FP exceptions previously enabled.
	* sysdeps/powerpc/fpu/fesetenv.c (fesetenv): Change mask to merge
	exceptions from env.  Use __fe_nomask_env() or __fe_mask_env() when
	transitioning from all exceptions disabled to any exception enabled
	or visa versa.
	* sysdeps/powerpc/fpu/feupdateenv.c (__feupdateenv): Change mask to
	merge exceptions from env.  Call __fe_nomask_env or __fe_mask_env
	when transitioning from all exceptions disabled to any exception
	enabled or visa versa.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/fe_nomask.c: Moved to...
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/fe_nomask.c: ...here.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/fe_nomask.c: Moved to...
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/fpu/fe_nomask.c: ...here.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/fe_mask.c: New file.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/fpu/fe_mask.c: New file.

1 files changed, 13 insertions, 6 deletions

diff --git a/sysdeps/powerpc/fpu/feholdexcpt.c b/sysdeps/powerpc/fpu/feholdexcpt.c
index 150becd678..c9432248db 100644
--- a/sysdeps/powerpc/fpu/feholdexcpt.c
+++ b/sysdeps/powerpc/fpu/feholdexcpt.c
@@ -22,17 +22,24 @@
 int
 feholdexcept (fenv_t *envp)
 {
-  fenv_union_t u;
+  fenv_union_t old, new;
 
-  /* Get the current state.  */
-  u.fenv = *envp = fegetenv_register ();
+  /* Save the currently set exceptions.  */
+  old.fenv = *envp = fegetenv_register ();
 
-  /* Clear everything except for the rounding mode and non-IEEE arithmetic
+  /* Clear everything except for the rounding modes and non-IEEE arithmetic
      flag.  */
-  u.l[1] = u.l[1] & 7;
+  new.l[1] = old.l[1] & 7;
+  new.l[0] = old.l[0];
+  
+  /* If the old env had any eabled exceptions, then mask SIGFPE in the
+     MSR FE0/FE1 bits.  This may allow the FPU to run faster because it
+     always takes the default action and can not generate SIGFPE. */
+  if ((old.l[1] & 0x000000F8) != 0)
+    (void)__fe_mask_env ();
 
   /* Put the new state in effect.  */
-  fesetenv_register (u.fenv);
+  fesetenv_register (new.fenv);
 
   return 0;
 }