> > Maybe we can add a check in gcc/configure.ac to see if gcc_cv_ld > > supports %got_pc_hi20 and adjust the default for -m[no]-explicit-relocs?
> I think this is a good way, I'll look at adding a check. The following should work. I've tested it locally by building GCC with both old (2.38 with patch) and new (trunk) Binutils. Ok for trunk? I simply checked as instead of ld. If as supports explicitly relocations, the produced .o file won't be supported by an old ld even if we use -mno-explicit-relocs (because as will generate new relocation types for la.local etc). So such a mismatch between as and ld can be considered "completely broken" and we don't need to support it. And, the Alpha port also check the assembler for the default of -mexplicit- relocs. This should be documented in invoke.texi, but currently it does not mention -mexplicit-relocs for LoongArch at all. So I'll submit the doclater in another patch. -- >8 -- The assembly produced with -mexplicit-relocs is not supported by gas <= 2.39. Check if the assembler supports explicit relocations and set the default accordingly. gcc/ChangeLog: * configure.ac (HAVE_AS_EXPLICIT_RELOCS): Define to 1 if the assembler supports explicit relocation for LoongArch. * configure: Regenerate. * config/loongarch/loongarch-opts.h (HAVE_AS_EXPLICIT_RELOCS): Define to 0 if not defined. * config/loongarch/genopts/loongarch.opt.in (TARGET_EXPLICIT_RELOCS): Default to HAVE_AS_EXPLICIT_RELOCS. * config/loongarch/loongarch.opt: Regenerate. --- gcc/config/loongarch/genopts/loongarch.opt.in | 2 +- gcc/config/loongarch/loongarch-opts.h | 4 ++ gcc/config/loongarch/loongarch.opt | 2 +- gcc/configure | 37 +++++++++++++++++-- gcc/configure.ac | 7 +++- 5 files changed, 46 insertions(+), 6 deletions(-) diff --git a/gcc/config/loongarch/genopts/loongarch.opt.in b/gcc/config/loongarch/genopts/loongarch.opt.in index 6f39500935d..a571b6b7524 100644 --- a/gcc/config/loongarch/genopts/loongarch.opt.in +++ b/gcc/config/loongarch/genopts/loongarch.opt.in @@ -155,7 +155,7 @@ Target Joined RejectNegative UInteger Var(loongarch_max_inline_memcpy_size) Init -mmax-inline-memcpy-size=SIZE Set the max size of memcpy to inline, default is 1024. mexplicit-relocs -Target Var(TARGET_EXPLICIT_RELOCS) Init(1) +Target Var(TARGET_EXPLICIT_RELOCS) Init(HAVE_AS_EXPLICIT_RELOCS) Use %reloc() assembly operators. ; The code model option names for -mcmodel. diff --git a/gcc/config/loongarch/loongarch-opts.h b/gcc/config/loongarch/loongarch-opts.h index eaa6fc07448..da24ecd2b50 100644 --- a/gcc/config/loongarch/loongarch-opts.h +++ b/gcc/config/loongarch/loongarch-opts.h @@ -87,4 +87,8 @@ loongarch_config_target (struct loongarch_target *target, while -m[no]-memcpy imposes a global constraint. */ #define TARGET_DO_OPTIMIZE_BLOCK_MOVE_P loongarch_do_optimize_block_move_p() +#ifndef HAVE_AS_EXPLICIT_RELOCS +#define HAVE_AS_EXPLICIT_RELOCS 0 +#endif + #endif /* LOONGARCH_OPTS_H */ diff --git a/gcc/config/loongarch/loongarch.opt b/gcc/config/loongarch/loongarch.opt index 7a8c5b44418..9df7e187283 100644 --- a/gcc/config/loongarch/loongarch.opt +++ b/gcc/config/loongarch/loongarch.opt @@ -162,7 +162,7 @@ Target Joined RejectNegative UInteger Var(loongarch_max_inline_memcpy_size) Init -mmax-inline-memcpy-size=SIZE Set the max size of memcpy to inline, default is 1024. mexplicit-relocs -Target Var(TARGET_EXPLICIT_RELOCS) Init(1) +Target Var(TARGET_EXPLICIT_RELOCS) Init(HAVE_AS_EXPLICIT_RELOCS) Use %reloc() assembly operators. ; The code model option names for -mcmodel. diff --git a/gcc/configure b/gcc/configure index 62872d132ea..7eb9479ae8e 100755 --- a/gcc/configure +++ b/gcc/configure @@ -19674,7 +19674,7 @@ else lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2 lt_status=$lt_dlunknown cat > conftest.$ac_ext <<_LT_EOF -#line 19679 "configure" +#line 19677 "configure" #include "confdefs.h" #if HAVE_DLFCN_H @@ -19780,7 +19780,7 @@ else lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2 lt_status=$lt_dlunknown cat > conftest.$ac_ext <<_LT_EOF -#line 19785 "configure" +#line 19783 "configure" #include "confdefs.h" #if HAVE_DLFCN_H @@ -28771,7 +28771,7 @@ $as_echo "#define HAVE_AS_MARCH_ZIFENCEI 1" >>confdefs.h fi ;; - loongarch*-*-*) + loongarch*-*-*) { $as_echo "$as_me:${as_lineno-$LINENO}: checking assembler for .dtprelword support" >&5 $as_echo_n "checking assembler for .dtprelword support... " >&6; } if ${gcc_cv_as_loongarch_dtprelword+:} false; then : @@ -28807,6 +28807,37 @@ if test $gcc_cv_as_loongarch_dtprelword != yes; then $as_echo "#define HAVE_AS_DTPRELWORD 1" >>confdefs.h fi + { $as_echo "$as_me:${as_lineno-$LINENO}: checking assembler for explicit relocation support" >&5 +$as_echo_n "checking assembler for explicit relocation support... " >&6; } +if ${gcc_cv_as_loongarch_explicit_relocs+:} false; then : + $as_echo_n "(cached) " >&6 +else + gcc_cv_as_loongarch_explicit_relocs=no + if test x$gcc_cv_as != x; then + $as_echo 'a:pcalau12i $t0,%pc_hi20(a)' > conftest.s + if { ac_try='$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_loongarch_explicit_relocs=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: $gcc_cv_as_loongarch_explicit_relocs" >&5 +$as_echo "$gcc_cv_as_loongarch_explicit_relocs" >&6; } +if test $gcc_cv_as_loongarch_explicit_relocs = yes; then + +$as_echo "#define HAVE_AS_EXPLICIT_RELOCS 1" >>confdefs.h + +fi + ;; s390*-*-*) { $as_echo "$as_me:${as_lineno-$LINENO}: checking assembler for .gnu_attribute support" >&5 diff --git a/gcc/configure.ac b/gcc/configure.ac index 446747311a6..e5f708c6b38 100644 --- a/gcc/configure.ac +++ b/gcc/configure.ac @@ -5287,7 +5287,7 @@ configured with --enable-newlib-nano-formatted-io.]) [AC_DEFINE(HAVE_AS_MARCH_ZIFENCEI, 1, [Define if the assembler understands -march=rv*_zifencei.])]) ;; - loongarch*-*-*) + loongarch*-*-*) gcc_GAS_CHECK_FEATURE([.dtprelword support], gcc_cv_as_loongarch_dtprelword, [2,18,0],, [.section .tdata,"awT",@progbits @@ -5297,6 +5297,11 @@ x: .dtprelword x+0x8000],, [AC_DEFINE(HAVE_AS_DTPRELWORD, 1, [Define if your assembler supports .dtprelword.])]) + gcc_GAS_CHECK_FEATURE([explicit relocation support], + gcc_cv_as_loongarch_explicit_relocs,, + [a:pcalau12i $t0,%pc_hi20(a)],, + [AC_DEFINE(HAVE_AS_EXPLICIT_RELOCS, 1, + [Define if your assembler supports explicit relocation.])]) ;; s390*-*-*) gcc_GAS_CHECK_FEATURE([.gnu_attribute support], -- 2.37.1