* config/tc-mips.c (mips_fix_loongson2f, mips_fix_loongson2f_nop,

        mips_fix_loongson2f_jump): New variables.
        (md_longopts): Add New options -mfix-loongson2f-nop/jump,
        -mno-fix-loongson2f-nop/jump.
        (md_parse_option): Initialize variables via above options.
        (options): New enums for the above options.
        (md_begin): Initialize nop_insn from LOONGSON2F_NOP_INSN.
        (fix_loongson2f, fix_loongson2f_nop, fix_loongson2f_jump):
        New functions.
        (append_insn): call fix_loongson2f().
        (mips_handle_align): Replace the implicit nops.
        * config/tc-mips.h (MAX_MEM_FOR_RS_ALIGN_CODE): Modified
        for the new mips_handle_align().
        * doc/c-mips.texi: Document the new options.

        * gas/mips/loongson-2f-2.s: New test of -mfix-loongson2f-nop.
        * gas/mips/loongson-2f-2.d: Likewise.
        * gas/mips/loongson-2f-3.s: New test of -mfix-loongson2f-jump.
        * gas/mips/loongson-2f-3.d: Likewise.
        * gas/mips/mips.exp: Run the new tests.

        * opcode/mips.h (LOONGSON2F_NOP_INSN): New macro.

2 files changed, 120 insertions, 14 deletions

diff --git a/gas/config/tc-mips.c b/gas/config/tc-mips.c
index 94128fe..f901ae4 100644
--- a/gas/config/tc-mips.c
+++ b/gas/config/tc-mips.c
@@ -1,6 +1,7 @@
 /* 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
@@ -751,7 +752,8 @@ static const unsigned int mips16_to_32_reg_map[] =
 
 /* 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,
@@ -761,6 +763,15 @@ enum fix_vr4120_class {
   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.  */
@@ -1048,8 +1059,9 @@ static struct {
 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);
@@ -1918,6 +1930,8 @@ md_begin (void)
 	      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;
 		}
 	    }
@@ -2731,6 +2745,54 @@ nops_for_insn_or_target (const struct mips_cl_insn *hist,
   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.  */
@@ -2744,6 +2806,9 @@ append_insn (struct mips_cl_insn *ip, expressionS *address_expr,
   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 ();
 
@@ -11216,6 +11281,10 @@ enum options
     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,
@@ -11304,6 +11373,10 @@ struct option md_longopts[] =
   {"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},
@@ -11571,6 +11644,22 @@ md_parse_option (int c, char *arg)
       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;
@@ -11785,6 +11874,8 @@ md_parse_option (int c, char *arg)
       return 0;
     }
 
+    mips_fix_loongson2f = mips_fix_loongson2f_nop || mips_fix_loongson2f_jump;
+
   return 1;
 }
 
@@ -14790,6 +14881,8 @@ void
 mips_handle_align (fragS *fragp)
 {
   char *p;
+  int bytes, size, excess;
+  valueT opcode;
 
   if (fragp->fr_type != rs_align_code)
     return;
@@ -14797,17 +14890,28 @@ mips_handle_align (fragS *fragp)
   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
@@ -15519,6 +15623,8 @@ MIPS options:\n\
 -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\
diff --git a/gas/config/tc-mips.h b/gas/config/tc-mips.h
index 4bdf807..502fa8e 100644
--- a/gas/config/tc-mips.h
+++ b/gas/config/tc-mips.h
@@ -1,6 +1,6 @@
 /* tc-mips.h -- header file for tc-mips.c.
    Copyright 1993, 1994, 1995, 1996, 1997, 2000, 2001, 2002, 2003, 2004,
-   2005, 2006, 2007, 2008  Free Software Foundation, Inc.
+   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 support by Ian Lance Taylor of Cygnus Support.
@@ -59,7 +59,7 @@ extern char mips_nop_opcode (void);
 extern void mips_handle_align (struct frag *);
 #define HANDLE_ALIGN(fragp)  mips_handle_align (fragp)
 
-#define MAX_MEM_FOR_RS_ALIGN_CODE  (1 + 2)
+#define MAX_MEM_FOR_RS_ALIGN_CODE  (3 + 4)
 
 struct insn_label_list;
 struct mips_segment_info {