This is the mail archive of the
gdb-patches@sources.redhat.com
mailing list for the GDB project.
Re: [rfa:i386] Add mmx registers
Andrew Cagney <ac131313@ges.redhat.com> writes:
Hello,
This adds mmx registers to the i386.
Great, a few nits though :-(
* Please rename is_mmx_regnum() to mmx_regnum_p().
* Please rename nr_mmx_regs to mmx_num_regs.
* Why do you use regcache_raw_read_as_address() in
mmx_regnum_to_fp_regnum? Looks misleading to me...
(because I happen to know what the function does :-)
I'll rename the function to ..._as_longest().
I'll fix the others.
Done, this is what I committed.
It also includes raw versions of the ..._unsigned() functions since the
mmx code needs to access the raw register cache.
Andrew
2002-08-13 Andrew Cagney <cagney@redhat.com>
* i386-tdep.c (i386_register_name): Handle mmx registers.
(mmx_regnum_p): New function.
(i386_mmx_names): New array.
(mmx_num_regs): New variable.
(i386_pseudo_register_read): New function.
(i386_pseudo_register_write): New function.
(mmx_regnum_to_fp_regnum): New function. Code from Fernando Nasser.
* regcache.c (regcache_raw_read_unsigned): New function.
(regcache_raw_read_signed): New function.
* regcache.h (regcache_raw_read_unsigned): Declare.
(regcache_raw_read_signed): Declare.
Index: i386-tdep.c
===================================================================
RCS file: /cvs/src/src/gdb/i386-tdep.c,v
retrieving revision 1.75
diff -u -r1.75 i386-tdep.c
--- i386-tdep.c 13 Aug 2002 13:58:50 -0000 1.75
+++ i386-tdep.c 13 Aug 2002 14:31:01 -0000
@@ -56,6 +56,23 @@
"mxcsr"
};
+/* MMX registers. */
+
+static char *i386_mmx_names[] =
+{
+ "mm0", "mm1", "mm2", "mm3",
+ "mm4", "mm5", "mm6", "mm7"
+};
+static const int mmx_num_regs = (sizeof (i386_mmx_names)
+ / sizeof (i386_mmx_names[0]));
+#define MM0_REGNUM (NUM_REGS)
+
+static int
+mmx_regnum_p (int reg)
+{
+ return (reg >= MM0_REGNUM && reg < MM0_REGNUM + mmx_num_regs);
+}
+
/* Return the name of register REG. */
const char *
@@ -63,6 +80,8 @@
{
if (reg < 0)
return NULL;
+ if (mmx_regnum_p (reg))
+ return i386_mmx_names[reg - MM0_REGNUM];
if (reg >= sizeof (i386_register_names) / sizeof (*i386_register_names))
return NULL;
@@ -1090,9 +1109,64 @@
if (IS_SSE_REGNUM (regnum))
return builtin_type_vec128i;
+ if (mmx_regnum_p (regnum))
+ return builtin_type_vec64i;
+
return builtin_type_int;
}
+/* Map a cooked register onto a raw register or memory. For the i386,
+ the MMX registers need to be mapped onto floating point registers. */
+
+static int
+mmx_regnum_to_fp_regnum (struct regcache *regcache, int regnum)
+{
+ int mmxi;
+ ULONGEST fstat;
+ int tos;
+ int fpi;
+ mmxi = regnum - MM0_REGNUM;
+ regcache_raw_read_unsigned (regcache, FSTAT_REGNUM, &fstat);
+ tos = (fstat >> 11) & 0x7;
+ fpi = (mmxi + tos) % 8;
+ return (FP0_REGNUM + fpi);
+}
+
+static void
+i386_pseudo_register_read (struct gdbarch *gdbarch, struct regcache *regcache,
+ int regnum, void *buf)
+{
+ if (mmx_regnum_p (regnum))
+ {
+ char *mmx_buf = alloca (MAX_REGISTER_RAW_SIZE);
+ int fpnum = mmx_regnum_to_fp_regnum (regcache, regnum);
+ regcache_raw_read (regcache, fpnum, mmx_buf);
+ /* Extract (always little endian). */
+ memcpy (buf, mmx_buf, REGISTER_RAW_SIZE (regnum));
+ }
+ else
+ regcache_raw_read (regcache, regnum, buf);
+}
+
+static void
+i386_pseudo_register_write (struct gdbarch *gdbarch, struct regcache *regcache,
+ int regnum, const void *buf)
+{
+ if (mmx_regnum_p (regnum))
+ {
+ char *mmx_buf = alloca (MAX_REGISTER_RAW_SIZE);
+ int fpnum = mmx_regnum_to_fp_regnum (regcache, regnum);
+ /* Read ... */
+ regcache_raw_read (regcache, fpnum, mmx_buf);
+ /* ... Modify ... (always little endian). */
+ memcpy (mmx_buf, buf, REGISTER_RAW_SIZE (regnum));
+ /* ... Write. */
+ regcache_raw_write (regcache, fpnum, mmx_buf);
+ }
+ else
+ regcache_raw_write (regcache, regnum, buf);
+}
+
/* Return true iff register REGNUM's virtual format is different from
its raw format. Note that this definition assumes that the host
supports IEEE 32-bit floats, since it doesn't say that SSE
@@ -1485,6 +1559,11 @@
set_gdbarch_saved_pc_after_call (gdbarch, i386_saved_pc_after_call);
set_gdbarch_frame_num_args (gdbarch, i386_frame_num_args);
set_gdbarch_pc_in_sigtramp (gdbarch, i386_pc_in_sigtramp);
+
+ /* Wire in the MMX registers. */
+ set_gdbarch_num_pseudo_regs (gdbarch, mmx_num_regs);
+ set_gdbarch_pseudo_register_read (gdbarch, i386_pseudo_register_read);
+ set_gdbarch_pseudo_register_write (gdbarch, i386_pseudo_register_write);
/* Hook in ABI-specific overrides, if they have been registered. */
gdbarch_init_osabi (info, gdbarch, osabi);
Index: regcache.c
===================================================================
RCS file: /cvs/src/src/gdb/regcache.c,v
retrieving revision 1.51
diff -u -r1.51 regcache.c
--- regcache.c 13 Aug 2002 13:58:50 -0000 1.51
+++ regcache.c 13 Aug 2002 14:31:02 -0000
@@ -661,6 +661,31 @@
}
void
+regcache_raw_read_signed (struct regcache *regcache, int regnum, LONGEST *val)
+{
+ char *buf;
+ gdb_assert (regcache != NULL);
+ gdb_assert (regnum >= 0 && regnum < regcache->descr->nr_raw_registers);
+ buf = alloca (regcache->descr->sizeof_register[regnum]);
+ regcache_raw_read (regcache, regnum, buf);
+ (*val) = extract_signed_integer (buf,
+ regcache->descr->sizeof_register[regnum]);
+}
+
+void
+regcache_raw_read_unsigned (struct regcache *regcache, int regnum,
+ ULONGEST *val)
+{
+ char *buf;
+ gdb_assert (regcache != NULL);
+ gdb_assert (regnum >= 0 && regnum < regcache->descr->nr_raw_registers);
+ buf = alloca (regcache->descr->sizeof_register[regnum]);
+ regcache_raw_read (regcache, regnum, buf);
+ (*val) = extract_unsigned_integer (buf,
+ regcache->descr->sizeof_register[regnum]);
+}
+
+void
read_register_gen (int regnum, char *buf)
{
gdb_assert (current_regcache != NULL);
Index: regcache.h
===================================================================
RCS file: /cvs/src/src/gdb/regcache.h,v
retrieving revision 1.13
diff -u -r1.13 regcache.h
--- regcache.h 13 Aug 2002 13:58:50 -0000 1.13
+++ regcache.h 13 Aug 2002 14:31:02 -0000
@@ -38,6 +38,10 @@
void regcache_raw_read (struct regcache *regcache, int rawnum, void *buf);
void regcache_raw_write (struct regcache *regcache, int rawnum,
const void *buf);
+extern void regcache_raw_read_signed (struct regcache *regcache,
+ int regnum, LONGEST *val);
+extern void regcache_raw_read_unsigned (struct regcache *regcache,
+ int regnum, ULONGEST *val);
int regcache_valid_p (struct regcache *regcache, int regnum);
/* Transfer a cooked register [0..NUM_REGS+NUM_PSEUDO_REGS). */