diff mbox series

Tidy objdump opb expressions

Message ID ZiBuz+tojjqatOw0@squeak.grove.modra.org
State New
Headers
Series Tidy objdump opb expressions |

Checks

Context Check Description
linaro-tcwg-bot/tcwg_binutils_build--master-arm warning Patch is already merged
linaro-tcwg-bot/tcwg_binutils_build--master-aarch64 warning Patch is already merged

Commit Message

Alan Modra April 18, 2024, 12:52 a.m. UTC 
  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 mbox series

Patch

diff --git a/binutils/objdump.c b/binutils/objdump.c
index 6396174d50f..f92e14b33e4 100644
--- 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)