Tidy objdump opb expressions

I don't think any of these can overflow, but since all of the
expressions I'm editing here are inside a while loop with condition
addr_offset < stop_offset, this change makes it more obvious that they
can't overflow.

	* objdump.c (disassemble_bytes): Calculate octet expressions
	involving both addr_offset and stop_offset by first
	subtracting addr_offset from stop_offset.

diff --git a/binutils/objdump.c b/binutils/objdump.c
index 6396174d50ff708fc7f87b81a2416dec8c412697..f92e14b33e4e423623e224f76835d2c432eb8247 100644 (file)
--- a/binutils/objdump.c
+++ b/binutils/objdump.c
@@ -3356,28 +3356,28 @@ disassemble_bytes (struct disassemble_info *inf,
       /* If we see more than SKIP_ZEROES octets of zeroes, we just
         print `...'.  */
       if (! disassemble_zeroes)
-       for (; addr_offset * opb + octets < stop_offset * opb; octets++)
+       for (; octets < (stop_offset - addr_offset) * opb; octets++)
          if (data[addr_offset * opb + octets] != 0)
            break;
       if (! disassemble_zeroes
          && (inf->insn_info_valid == 0
              || inf->branch_delay_insns == 0)
          && (octets >= skip_zeroes
-             || (addr_offset * opb + octets == stop_offset * opb
+             || (octets == (stop_offset - addr_offset) * opb
                  && octets < skip_zeroes_at_end)))
        {
          /* If there are more nonzero octets to follow, we only skip
             zeroes in multiples of 4, to try to avoid running over
             the start of an instruction which happens to start with
             zero.  */
-         if (addr_offset * opb + octets != stop_offset * opb)
+         if (octets != (stop_offset - addr_offset) * opb)
            octets &= ~3;
 
          /* If we are going to display more data, and we are displaying
             file offsets, then tell the user how many zeroes we skip
             and the file offset from where we resume dumping.  */
          if (display_file_offsets
-             && addr_offset + octets / opb < stop_offset)
+             && octets / opb < stop_offset - addr_offset)
            printf (_("\t... (skipping %lu zeroes, "
                      "resuming at file offset: 0x%lx)\n"),
                    (unsigned long) (octets / opb),
@@ -3529,7 +3529,7 @@ disassemble_bytes (struct disassemble_info *inf,
              bfd_vma j;
 
              octets = octets_per_line;
-             if (addr_offset + octets / opb > stop_offset)
+             if (octets / opb > stop_offset - addr_offset)
                octets = (stop_offset - addr_offset) * opb;
 
              for (j = addr_offset * opb; j < addr_offset * opb + octets; ++j)