[PATCH] avoid strange arithmetic with strings in i386-dis.c

[Roland McGrath <mcgrathr@google.com>]

This makes the code a bit less baroque, and also avoids warnings from some
compilers.  After the various changes I've committed in the last couple of
days, this is enough to get binutils (excluding gold) to build warning-free
with a recent Clang.

OK for trunk and 2.24?

Thanks,
Roland


opcodes/
	* i386-dis.c (oappend_maybe_intel): New function.
	(OP_ST, OP_STi, append_seg, OP_I, OP_I64, OP_sI, OP_ESreg): Use it.
	(OP_C, OP_T, CMP_Fixup, OP_EX_VexImmW): Likewise.
	(VCMP_Fixup, VPCMP_Fixup, PCLMUL_Fixup): Likewise.

--- a/opcodes/i386-dis.c
+++ b/opcodes/i386-dis.c
@@ -1,6 +1,6 @@
 /* Print i386 instructions for GDB, the GNU debugger.
    Copyright 1988, 1989, 1991, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
-   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
+   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013
    Free Software Foundation, Inc.

    This file is part of the GNU opcodes library.
@@ -13095,17 +13095,27 @@ dofloat (int sizeflag)
     }
 }

+/* Like oappend (below), but S is a string starting with '%'.
+   In Intel syntax, the '%' is elided.  */
+static void
+oappend_maybe_intel (const char *s)
+{
+  if (intel_syntax)
+    ++s;
+  oappend (s);
+}
+
 static void
 OP_ST (int bytemode ATTRIBUTE_UNUSED, int sizeflag ATTRIBUTE_UNUSED)
 {
-  oappend ("%st" + intel_syntax);
+  oappend_maybe_intel ("%st");
 }

 static void
 OP_STi (int bytemode ATTRIBUTE_UNUSED, int sizeflag ATTRIBUTE_UNUSED)
 {
   sprintf (scratchbuf, "%%st(%d)", modrm.rm);
-  oappend (scratchbuf + intel_syntax);
+  oappend_maybe_intel (scratchbuf);
 }

 /* Capital letters in template are macros.  */
@@ -13629,32 +13639,32 @@ append_seg (void)
   if (prefixes & PREFIX_CS)
     {
       used_prefixes |= PREFIX_CS;
-      oappend ("%cs:" + intel_syntax);
+      oappend_maybe_intel ("%cs:");
     }
   if (prefixes & PREFIX_DS)
     {
       used_prefixes |= PREFIX_DS;
-      oappend ("%ds:" + intel_syntax);
+      oappend_maybe_intel ("%ds:");
     }
   if (prefixes & PREFIX_SS)
     {
       used_prefixes |= PREFIX_SS;
-      oappend ("%ss:" + intel_syntax);
+      oappend_maybe_intel ("%ss:");
     }
   if (prefixes & PREFIX_ES)
     {
       used_prefixes |= PREFIX_ES;
-      oappend ("%es:" + intel_syntax);
+      oappend_maybe_intel ("%es:");
     }
   if (prefixes & PREFIX_FS)
     {
       used_prefixes |= PREFIX_FS;
-      oappend ("%fs:" + intel_syntax);
+      oappend_maybe_intel ("%fs:");
     }
   if (prefixes & PREFIX_GS)
     {
       used_prefixes |= PREFIX_GS;
-      oappend ("%gs:" + intel_syntax);
+      oappend_maybe_intel ("%gs:");
     }
 }

@@ -14904,7 +14914,7 @@ OP_I (int bytemode, int sizeflag)
   op &= mask;
   scratchbuf[0] = '$';
   print_operand_value (scratchbuf + 1, 1, op);
-  oappend (scratchbuf + intel_syntax);
+  oappend_maybe_intel (scratchbuf);
   scratchbuf[0] = '\0';
 }

@@ -14958,7 +14968,7 @@ OP_I64 (int bytemode, int sizeflag)
   op &= mask;
   scratchbuf[0] = '$';
   print_operand_value (scratchbuf + 1, 1, op);
-  oappend (scratchbuf + intel_syntax);
+  oappend_maybe_intel (scratchbuf);
   scratchbuf[0] = '\0';
 }

@@ -15012,7 +15022,7 @@ OP_sI (int bytemode, int sizeflag)

   scratchbuf[0] = '$';
   print_operand_value (scratchbuf + 1, 1, op);
-  oappend (scratchbuf + intel_syntax);
+  oappend_maybe_intel (scratchbuf);
 }

 static void
@@ -15194,7 +15204,7 @@ OP_ESreg (int code, int sizeflag)
 	  intel_operand_size (b_mode, sizeflag);
 	}
     }
-  oappend ("%es:" + intel_syntax);
+  oappend_maybe_intel ("%es:");
   ptr_reg (code, sizeflag);
 }

@@ -15247,7 +15257,7 @@ OP_C (int dummy ATTRIBUTE_UNUSED, int sizeflag
ATTRIBUTE_UNUSED)
   else
     add = 0;
   sprintf (scratchbuf, "%%cr%d", modrm.reg + add);
-  oappend (scratchbuf + intel_syntax);
+  oappend_maybe_intel (scratchbuf);
 }

 static void
@@ -15270,7 +15280,7 @@ static void
 OP_T (int dummy ATTRIBUTE_UNUSED, int sizeflag ATTRIBUTE_UNUSED)
 {
   sprintf (scratchbuf, "%%tr%d", modrm.reg);
-  oappend (scratchbuf + intel_syntax);
+  oappend_maybe_intel (scratchbuf);
 }

 static void
@@ -15715,7 +15725,7 @@ CMP_Fixup (int bytemode ATTRIBUTE_UNUSED, int
sizeflag ATTRIBUTE_UNUSED)
       /* We have a reserved extension byte.  Output it directly.  */
       scratchbuf[0] = '$';
       print_operand_value (scratchbuf + 1, 1, cmp_type);
-      oappend (scratchbuf + intel_syntax);
+      oappend_maybe_intel (scratchbuf);
       scratchbuf[0] = '\0';
     }
 }
@@ -16240,7 +16250,7 @@ OP_EX_VexImmW (int bytemode, int sizeflag)
       /* Output the imm8 directly.  */
       scratchbuf[0] = '$';
       print_operand_value (scratchbuf + 1, 1, vex_imm8 & 0xf);
-      oappend (scratchbuf + intel_syntax);
+      oappend_maybe_intel (scratchbuf);
       scratchbuf[0] = '\0';
       codep++;
     }
@@ -16469,7 +16479,7 @@ VCMP_Fixup (int bytemode ATTRIBUTE_UNUSED, int
sizeflag ATTRIBUTE_UNUSED)
       /* We have a reserved extension byte.  Output it directly.  */
       scratchbuf[0] = '$';
       print_operand_value (scratchbuf + 1, 1, cmp_type);
-      oappend (scratchbuf + intel_syntax);
+      oappend_maybe_intel (scratchbuf);
       scratchbuf[0] = '\0';
     }
 }
@@ -16516,7 +16526,7 @@ VPCMP_Fixup (int bytemode ATTRIBUTE_UNUSED,
       /* We have a reserved extension byte.  Output it directly.  */
       scratchbuf[0] = '$';
       print_operand_value (scratchbuf + 1, 1, cmp_type);
-      oappend (scratchbuf + intel_syntax);
+      oappend_maybe_intel (scratchbuf);
       scratchbuf[0] = '\0';
     }
 }
@@ -16564,7 +16574,7 @@ PCLMUL_Fixup (int bytemode ATTRIBUTE_UNUSED,
       /* We have a reserved extension byte.  Output it directly.  */
       scratchbuf[0] = '$';
       print_operand_value (scratchbuf + 1, 1, pclmul_type);
-      oappend (scratchbuf + intel_syntax);
+      oappend_maybe_intel (scratchbuf);
       scratchbuf[0] = '\0';
     }
 }