[Sbcl-commits] CVS: sbcl/src/runtime alpha-linux-os.c,1.9,1.10

[Christophe R. <cr...@us...>]

Update of /cvsroot/sbcl/sbcl/src/runtime
In directory sc8-pr-cvs1:/tmp/cvs-serv17810/src/runtime

Modified Files:
	alpha-linux-os.c 
Log Message:
0.8.3.68:
	Kludge around an apparent problem in hardware/kernel/somewhere
	to do with denormalized float traps...
	... explicitly clear that bit in os_restore_fp_control();
	... document in BUGS;
	... handle ARITHMETIC-ERROR, not just DIVISION-BY-ZERO, so that
		ports without fp words in sigcontext pass the test


Index: alpha-linux-os.c
===================================================================
RCS file: /cvsroot/sbcl/sbcl/src/runtime/alpha-linux-os.c,v
retrieving revision 1.9
retrieving revision 1.10
diff -u -d -r1.9 -r1.10
--- alpha-linux-os.c	15 Sep 2003 13:45:17 -0000	1.9
+++ alpha-linux-os.c	15 Sep 2003 15:09:03 -0000	1.10
@@ -88,9 +88,17 @@
 os_restore_fp_control(os_context_t *context)
 {
     /* FIXME: 0x7E0000 is defined as something useful in constants.h,
-       but without the L, which would probably lead to 32/64-bit
+       but without the UL, which would probably lead to 32/64-bit
        errors if we simply used it here.  Ugh.  CSR, 2003-09-15 */
-    arch_set_fp_control(os_context_fp_control(context) & ~(0x7e0000L));
+    arch_set_fp_control(os_context_fp_control(context) & ~(0x7e0000UL) &
+			/* KLUDGE: for some reason that I don't
+			understand, by the time we get here the
+			"enable denormalized traps" bit in the fp
+			control word is set.  Since we really don't
+			want to tra every time someone types
+			LEAST-POSITIVE-SINGLE-FLOAT into the repl,
+			mask that bit out.  -- CSR, 2003-09-15 */
+			~(0x1UL<<6));
 }
 
 void os_flush_icache(os_vm_address_t address, os_vm_size_t length)