[binutils-gdb] x86: suppress optimization after potential non-insn

[binutils-gdb] x86: suppress optimization after potential non-insn

[Jan Beulich]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=175ce60f0ff7f3423b49c0d41a88a0c51a08ac03

commit 175ce60f0ff7f3423b49c0d41a88a0c51a08ac03
Author: Jan Beulich <jbeulich@suse.com>
Date:   Fri Dec 1 08:27:49 2023 +0100

    x86: suppress optimization after potential non-insn
    
    Just like avoiding to do other transformations potentially affected by
    stand-alone prefixes or direct data emission, also avoid optimization
    on the following insn.

Diff:
---
 gas/config/tc-i386.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c
index 059dd49feea..f2f1e3b9f64 100644
--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -5120,6 +5120,11 @@ md_assemble (char *line)
  retry:
   init_globals ();
 
+  /* Suppress optimization when the last thing we saw may not have been
+     a proper instruction (e.g. a stand-alone prefix or .byte).  */
+  if (last_insn->kind != last_insn_other)
+    i.no_optimize = true;
+
   /* First parse an instruction mnemonic & call i386_operand for the operands.
      We assume that the scrubber has arranged it so that line[0] is the valid
      start of a (possibly prefixed) mnemonic.  */