On Thu, Feb 13, 2014 at 3:46 PM, Roland McGrath <mcgra...@google.com> wrote: > Non-ancient assemblers support the "ud2" mnemonic, so there is no need > to emit the literal opcode as data. > > OK for trunk and 4.8?
I changed this to use .word due to openbsd3.1: http://gcc.gnu.org/ml/gcc-patches/2005-07/msg01347.html . I no longer have access to this older openbsd box so I don't object to this change. In fact I doubt we support any binutils that are pre 2.0 any more; so maybe move over unconditionally to ud. Thanks, Andrew Pinski > > > Thanks, > Roland > > > gcc/ > 2014-02-13 Roland McGrath <mcgra...@google.com> > > * configure.ac (HAVE_AS_IX86_UD2): New test for 'ud2' mnemonic. > * configure: Regenerated. > * config.in: Regenerated. > * config/i386/i386.md (trap) [HAVE_AS_IX86_UD2]: Use the mnemonic > instead of ASM_SHORT. > > --- a/gcc/config.in > +++ b/gcc/config.in > @@ -375,6 +375,12 @@ > #endif > > > +/* Define if your assembler supports the 'ud2' mnemonic. */ > +#ifndef USED_FOR_TARGET > +#undef HAVE_AS_IX86_UD2 > +#endif > + > + > /* Define if your assembler supports the lituse_jsrdirect relocation. */ > #ifndef USED_FOR_TARGET > #undef HAVE_AS_JSRDIRECT_RELOCS > --- a/gcc/config/i386/i386.md > +++ b/gcc/config/i386/i386.md > @@ -17843,7 +17843,13 @@ > (define_insn "trap" > [(trap_if (const_int 1) (const_int 6))] > "" > - { return ASM_SHORT "0x0b0f"; } > +{ > +#ifdef HAVE_AS_IX86_UD2 > + return "ud2"; > +#else > + return ASM_SHORT "0x0b0f"; > +#endif > +} > [(set_attr "length" "2")]) > > (define_expand "prefetch" > --- a/gcc/configure > +++ b/gcc/configure > @@ -25109,6 +25109,37 @@ $as_echo "#define > HAVE_AS_IX86_REP_LOCK_PREFIX 1" >>confdefs.h > > fi > > + { $as_echo "$as_me:${as_lineno-$LINENO}: checking assembler for > ud2 mnemonic" >&5 > +$as_echo_n "checking assembler for ud2 mnemonic... " >&6; } > +if test "${gcc_cv_as_ix86_ud2+set}" = set; then : > + $as_echo_n "(cached) " >&6 > +else > + gcc_cv_as_ix86_ud2=no > + if test x$gcc_cv_as != x; then > + $as_echo 'ud2' > conftest.s > + if { ac_try='$gcc_cv_as $gcc_cv_as_flags -o conftest.o conftest.s >&5' > + { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5 > + (eval $ac_try) 2>&5 > + ac_status=$? > + $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5 > + test $ac_status = 0; }; } > + then > + gcc_cv_as_ix86_ud2=yes > + else > + echo "configure: failed program was" >&5 > + cat conftest.s >&5 > + fi > + rm -f conftest.o conftest.s > + fi > +fi > +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $gcc_cv_as_ix86_ud2" >&5 > +$as_echo "$gcc_cv_as_ix86_ud2" >&6; } > +if test $gcc_cv_as_ix86_ud2 = yes; then > + > +$as_echo "#define HAVE_AS_IX86_UD2 1" >>confdefs.h > + > +fi > + > { $as_echo "$as_me:${as_lineno-$LINENO}: checking assembler for > R_386_TLS_GD_PLT reloc" >&5 > $as_echo_n "checking assembler for R_386_TLS_GD_PLT reloc... " >&6; } > if test "${gcc_cv_as_ix86_tlsgdplt+set}" = set; then : > --- a/gcc/configure.ac > +++ b/gcc/configure.ac > @@ -3895,6 +3895,12 @@ foo: nop > [AC_DEFINE(HAVE_AS_IX86_REP_LOCK_PREFIX, 1, > [Define if the assembler supports 'rep <insn>, lock <insn>'.])]) > > + gcc_GAS_CHECK_FEATURE([ud2 mnemonic], > + gcc_cv_as_ix86_ud2,,, > + [ud2],, > + [AC_DEFINE(HAVE_AS_IX86_UD2, 1, > + [Define if your assembler supports the 'ud2' mnemonic.])]) > + > gcc_GAS_CHECK_FEATURE([R_386_TLS_GD_PLT reloc], > gcc_cv_as_ix86_tlsgdplt,,, > [call tls_gd@tlsgdplt],
