[src/trunk]: src/sys/arch/i386/isa Support for proper siginfo FP codes. Also...

[skd <skd%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/75b6dce1a0bf
branches:  trunk
changeset: 552956:75b6dce1a0bf
user:      skd <skd%NetBSD.org@localhost>
date:      Tue Oct 07 14:35:37 2003 +0000

description:
Support for proper siginfo FP codes.  Also, set si_trap to fp status word.
Approved by fvdl.

diffstat:

 sys/arch/i386/isa/npx.c |  49 +++++++++++++++++++++++++++++++++++++++++--------
 1 files changed, 41 insertions(+), 8 deletions(-)

diffs (95 lines):

diff -r dd10be972888 -r 75b6dce1a0bf sys/arch/i386/isa/npx.c
--- a/sys/arch/i386/isa/npx.c   Tue Oct 07 14:12:36 2003 +0000
+++ b/sys/arch/i386/isa/npx.c   Tue Oct 07 14:35:37 2003 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: npx.c,v 1.95 2003/09/06 23:15:35 christos Exp $        */
+/*     $NetBSD: npx.c,v 1.96 2003/10/07 14:35:37 skd Exp $     */
 
 /*-
  * Copyright (c) 1991 The Regents of the University of California.
@@ -67,7 +67,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: npx.c,v 1.95 2003/09/06 23:15:35 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: npx.c,v 1.96 2003/10/07 14:35:37 skd Exp $");
 
 #if 0
 #define IPRINTF(x)     printf x
@@ -143,6 +143,7 @@
 #ifdef I686_CPU
 static int     npxdna_xmm(struct cpu_info  *);
 #endif /* I686_CPU */
+static int     x86fpflags_to_ksiginfo(u_int32_t flags);
 
 #ifdef I686_CPU
 #define        fxsave(addr)            __asm("fxsave %0" : "=m" (*addr))
@@ -361,7 +362,6 @@
        union savefpu *addr;
        struct intrframe *frame = &iframe;
        struct npx_softc *sc;
-       int code;
        ksiginfo_t ksi;
 
        sc = npx_softc;
@@ -451,15 +451,22 @@
                 * just before it is used).
                 */
                l->l_md.md_regs = (struct trapframe *)&frame->if_gs;
-#ifdef notyet
+
                /*
                 * Encode the appropriate code for detailed information on
                 * this exception.
                 */
-               code = XXX_ENCODE(addr->sv_ex_sw);
-#else
-               code = 0;       /* XXX */
-#endif
+
+               if (i386_use_fxsave) {
+                       ksi.ksi_code =
+                               x86fpflags_to_ksiginfo(addr->sv_xmm.sv_ex_sw);
+                       ksi.ksi_trap = (int)addr->sv_xmm.sv_ex_sw;
+               } else {
+                       ksi.ksi_code =
+                               x86fpflags_to_ksiginfo(addr->sv_87.sv_ex_sw);
+                       ksi.ksi_trap = (int)addr->sv_87.sv_ex_sw;
+               }
+
                trapsignal(l, &ksi);
        } else {
                /*
@@ -477,6 +484,32 @@
        return (1);
 }
 
+/* map x86 fp flags to ksiginfo fp codes               */
+/* see table 8-4 of the IA-32 Intel Architecture       */
+/* Software Developer's Manual, Volume 1               */
+/* XXX punting on the stack fault with FLTINV          */
+static int
+x86fpflags_to_ksiginfo(u_int32_t flags)
+{
+       int i;
+       static int x86fp_ksiginfo_table[] = {
+               FPE_FLTINV, /* bit 0 - invalid operation */
+               FPE_FLTRES, /* bit 1 - denormal operand */
+               FPE_FLTDIV, /* bit 2 - divide by zero   */
+               FPE_FLTOVF, /* bit 3 - fp overflow      */
+               FPE_FLTUND, /* bit 4 - fp underflow     */ 
+               FPE_FLTRES, /* bit 5 - fp precision     */
+               FPE_FLTINV, /* bit 6 - stack fault      */
+       };
+                                            
+       for(i=0;i < sizeof(x86fp_ksiginfo_table)/sizeof(int); i++) {
+               if (flags & (1 << i))
+                       return(x86fp_ksiginfo_table[i]);
+       }
+       /* punt if flags not set */
+       return(0);
+}
+
 /*
  * Implement device not available (DNA) exception
  *