/* tc-mips.c -- assemble code for a MIPS chip.
Copyright 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002,
- 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
+ 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
+ Free Software Foundation, Inc.
Contributed by the OSF and Ralph Campbell.
Written by Keith Knowles and Ralph Campbell, working independently.
Modified for ECOFF and R4000 support by Ian Lance Taylor of Cygnus
/* Classifies the kind of instructions we're interested in when
implementing -mfix-vr4120. */
-enum fix_vr4120_class {
+enum fix_vr4120_class
+{
FIX_VR4120_MACC,
FIX_VR4120_DMACC,
FIX_VR4120_MULT,
NUM_FIX_VR4120_CLASSES
};
+/* ...likewise -mfix-loongson2f-jump. */
+static bfd_boolean mips_fix_loongson2f_jump;
+
+/* ...likewise -mfix-loongson2f-nop. */
+static bfd_boolean mips_fix_loongson2f_nop;
+
+/* True if -mfix-loongson2f-nop or -mfix-loongson2f-jump passed. */
+static bfd_boolean mips_fix_loongson2f;
+
/* Given two FIX_VR4120_* values X and Y, bit Y of element X is set if
there must be at least one other instruction between an instruction
of type X and an instruction of type Y. */
enum mips_regclass { MIPS_GR_REG, MIPS_FP_REG, MIPS16_REG };
static void append_insn
- (struct mips_cl_insn *ip, expressionS *p, bfd_reloc_code_real_type *r);
+ (struct mips_cl_insn *, expressionS *, bfd_reloc_code_real_type *);
static void mips_no_prev_insn (void);
+static void macro_build (expressionS *, const char *, const char *, ...);
static void mips16_macro_build
(expressionS *, const char *, const char *, va_list);
static void load_register (int, expressionS *, int);
if (nop_insn.insn_mo == NULL && strcmp (name, "nop") == 0)
{
create_insn (&nop_insn, mips_opcodes + i);
+ if (mips_fix_loongson2f_nop)
+ nop_insn.insn_opcode = LOONGSON2F_NOP_INSN;
nop_insn.fixed_p = 1;
}
}
return nops;
}
+/* Fix NOP issue: Replace nops by "or at,at,zero". */
+
+static void
+fix_loongson2f_nop (struct mips_cl_insn * ip)
+{
+ if (strcmp (ip->insn_mo->name, "nop") == 0)
+ ip->insn_opcode = LOONGSON2F_NOP_INSN;
+}
+
+/* Fix Jump Issue: Eliminate instruction fetch from outside 256M region
+ jr target pc &= 'hffff_ffff_cfff_ffff. */
+
+static void
+fix_loongson2f_jump (struct mips_cl_insn * ip)
+{
+ if (strcmp (ip->insn_mo->name, "j") == 0
+ || strcmp (ip->insn_mo->name, "jr") == 0
+ || strcmp (ip->insn_mo->name, "jalr") == 0)
+ {
+ int sreg;
+ expressionS ep;
+
+ if (! mips_opts.at)
+ return;
+
+ sreg = EXTRACT_OPERAND (RS, *ip);
+ if (sreg == ZERO || sreg == KT0 || sreg == KT1 || sreg == ATREG)
+ return;
+
+ ep.X_op = O_constant;
+ ep.X_add_number = 0xcfff0000;
+ macro_build (&ep, "lui", "t,u", ATREG, BFD_RELOC_HI16);
+ ep.X_add_number = 0xffff;
+ macro_build (&ep, "ori", "t,r,i", ATREG, ATREG, BFD_RELOC_LO16);
+ macro_build (NULL, "and", "d,v,t", sreg, sreg, ATREG);
+ }
+}
+
+static void
+fix_loongson2f (struct mips_cl_insn * ip)
+{
+ if (mips_fix_loongson2f_nop)
+ fix_loongson2f_nop (ip);
+
+ if (mips_fix_loongson2f_jump)
+ fix_loongson2f_jump (ip);
+}
+
/* Output an instruction. IP is the instruction information.
ADDRESS_EXPR is an operand of the instruction to be used with
RELOC_TYPE. */
bfd_boolean relaxed_branch = FALSE;
segment_info_type *si = seg_info (now_seg);
+ if (mips_fix_loongson2f)
+ fix_loongson2f (ip);
+
/* Mark instruction labels in mips16 mode. */
mips16_mark_labels ();
OPTION_MNO_7000_HILO_FIX,
OPTION_FIX_24K,
OPTION_NO_FIX_24K,
+ OPTION_FIX_LOONGSON2F_JUMP,
+ OPTION_NO_FIX_LOONGSON2F_JUMP,
+ OPTION_FIX_LOONGSON2F_NOP,
+ OPTION_NO_FIX_LOONGSON2F_NOP,
OPTION_FIX_VR4120,
OPTION_NO_FIX_VR4120,
OPTION_FIX_VR4130,
{"mfix7000", no_argument, NULL, OPTION_M7000_HILO_FIX},
{"no-fix-7000", no_argument, NULL, OPTION_MNO_7000_HILO_FIX},
{"mno-fix7000", no_argument, NULL, OPTION_MNO_7000_HILO_FIX},
+ {"mfix-loongson2f-jump", no_argument, NULL, OPTION_FIX_LOONGSON2F_JUMP},
+ {"mno-fix-loongson2f-jump", no_argument, NULL, OPTION_NO_FIX_LOONGSON2F_JUMP},
+ {"mfix-loongson2f-nop", no_argument, NULL, OPTION_FIX_LOONGSON2F_NOP},
+ {"mno-fix-loongson2f-nop", no_argument, NULL, OPTION_NO_FIX_LOONGSON2F_NOP},
{"mfix-vr4120", no_argument, NULL, OPTION_FIX_VR4120},
{"mno-fix-vr4120", no_argument, NULL, OPTION_NO_FIX_VR4120},
{"mfix-vr4130", no_argument, NULL, OPTION_FIX_VR4130},
mips_fix_24k = 0;
break;
+ case OPTION_FIX_LOONGSON2F_JUMP:
+ mips_fix_loongson2f_jump = TRUE;
+ break;
+
+ case OPTION_NO_FIX_LOONGSON2F_JUMP:
+ mips_fix_loongson2f_jump = FALSE;
+ break;
+
+ case OPTION_FIX_LOONGSON2F_NOP:
+ mips_fix_loongson2f_nop = TRUE;
+ break;
+
+ case OPTION_NO_FIX_LOONGSON2F_NOP:
+ mips_fix_loongson2f_nop = FALSE;
+ break;
+
case OPTION_FIX_VR4120:
mips_fix_vr4120 = 1;
break;
return 0;
}
+ mips_fix_loongson2f = mips_fix_loongson2f_nop || mips_fix_loongson2f_jump;
+
return 1;
}
\f
mips_handle_align (fragS *fragp)
{
char *p;
+ int bytes, size, excess;
+ valueT opcode;
if (fragp->fr_type != rs_align_code)
return;
p = fragp->fr_literal + fragp->fr_fix;
if (*p)
{
- int bytes;
+ opcode = mips16_nop_insn.insn_opcode;
+ size = 2;
+ }
+ else
+ {
+ opcode = nop_insn.insn_opcode;
+ size = 4;
+ }
- bytes = fragp->fr_next->fr_address - fragp->fr_address - fragp->fr_fix;
- if (bytes & 1)
- {
- *p++ = 0;
- fragp->fr_fix++;
- }
- md_number_to_chars (p, mips16_nop_insn.insn_opcode, 2);
- fragp->fr_var = 2;
+ bytes = fragp->fr_next->fr_address - fragp->fr_address - fragp->fr_fix;
+ excess = bytes % size;
+ if (excess != 0)
+ {
+ /* If we're not inserting a whole number of instructions,
+ pad the end of the fixed part of the frag with zeros. */
+ memset (p, 0, excess);
+ p += excess;
+ fragp->fr_fix += excess;
}
+
+ md_number_to_chars (p, opcode, size);
+ fragp->fr_var = size;
}
static void
-mmt generate MT instructions\n\
-mno-mt do not generate MT instructions\n"));
fprintf (stream, _("\
+-mfix-loongson2f-jump work around Loongson2F JUMP instructions\n\
+-mfix-loongson2f-nop work around Loongson2F NOP errata\n\
-mfix-vr4120 work around certain VR4120 errata\n\
-mfix-vr4130 work around VR4130 mflo/mfhi errata\n\
-mfix-24k insert a nop after ERET and DERET instructions\n\
@c Copyright 1991, 1992, 1993, 1994, 1995, 1997, 1999, 2000, 2001,
-@c 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
+@c 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
@c Free Software Foundation, Inc.
@c This is part of the GAS manual.
@c For copying conditions, see the file as.texinfo.
@itemx -mips2
@itemx -mips3
@itemx -mips4
-@itemx -mips5
+@itemx -mips5xo
@itemx -mips32
@itemx -mips32r2
@itemx -mips64
Cause nops to be inserted if the read of the destination register
of an mfhi or mflo instruction occurs in the following two instructions.
+@item -mfix-loongson2f-jump
+@itemx -mno-fix-loongson2f-jump
+Eliminate instruction fetch from outside 256M region to work around the
+Loongson2F @samp{jump} instructions. Without it, under extreme cases,
+the kernel may crash. The issue has been solved in latest processor
+batches, but this fix has no side effect to them.
+
+@item -mfix-loongson2f-nop
+@itemx -mno-fix-loongson2f-nop
+Replace nops by @code{or at,at,zero} to work around the Loongson2F
+@samp{nop} errata. Without it, under extreme cases, cpu might
+deadlock. The issue has been solved in latest loongson2f batches, but
+this fix has no side effect to them.
+
@item -mfix-vr4120
@itemx -mno-fix-vr4120
Insert nops to work around certain VR4120 errata. This option is