diff options
| -rw-r--r-- | sysdeps/loongarch/configure | 48 | ||||
| -rw-r--r-- | sysdeps/loongarch/configure.ac | 36 | ||||
| -rw-r--r-- | sysdeps/loongarch/start.S | 14 |
3 files changed, 95 insertions, 3 deletions
diff --git a/sysdeps/loongarch/configure b/sysdeps/loongarch/configure index 43b54d4965..6edd6d08a5 100644 --- a/sysdeps/loongarch/configure +++ b/sysdeps/loongarch/configure @@ -3,3 +3,51 @@ $as_echo "#define HIDDEN_VAR_NEEDS_DYNAMIC_RELOC 1" >>confdefs.h + +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if the toolchain is sufficient to build static PIE on LoongArch" >&5 +$as_echo_n "checking if the toolchain is sufficient to build static PIE on LoongArch... " >&6; } +if ${libc_cv_static_pie_on_loongarch+:} false; then : + $as_echo_n "(cached) " >&6 +else + + cat > conftest.S << EOF +.global _start +.type _start, @function +_start: + li.w \$a7, 93 + /* This ensures the assembler supports explicit reloc. */ + pcalau12i \$a0, %pc_hi20(x) + ld.w \$a0, \$a0, %pc_lo12(x) + syscall 0 + +.data +x: + .word 0 + /* This should produce an R_LARCH_RELATIVE in the static PIE. */ + .dword _start +EOF + libc_cv_static_pie_on_loongarch=no + if { ac_try='${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -static-pie -nostdlib -fPIE -o conftest conftest.S' + { { eval echo "\"\$as_me\":${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; }; } \ + && { ac_try='LC_ALL=C $READELF -Wr conftest | grep -q R_LARCH_RELATIVE' + { { eval echo "\"\$as_me\":${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 + libc_cv_static_pie_on_loongarch=yes + fi + rm -rf conftest.* +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_static_pie_on_loongarch" >&5 +$as_echo "$libc_cv_static_pie_on_loongarch" >&6; } + +if test "$libc_cv_static_pie_on_loongarch" = yes; then + $as_echo "#define SUPPORT_STATIC_PIE 1" >>confdefs.h + +fi diff --git a/sysdeps/loongarch/configure.ac b/sysdeps/loongarch/configure.ac index f744367bf3..a8a373bea3 100644 --- a/sysdeps/loongarch/configure.ac +++ b/sysdeps/loongarch/configure.ac @@ -4,3 +4,39 @@ GLIBC_PROVIDES dnl See aclocal.m4 in the top level source directory. dnl It is always possible to access static and hidden symbols in an dnl position independent way. AC_DEFINE(HIDDEN_VAR_NEEDS_DYNAMIC_RELOC) + +dnl Test if the toolchain is new enough for static PIE. +dnl We need a GAS supporting explicit reloc (older GAS produces stack-based +dnl reloc and triggers an internal error in the linker). And, we need GCC to +dnl pass the correct linker flags for static PIE. GCC >= 13 and GAS >= 2.40 +dnl satisify the requirement, but a distro may backport static PIE support into +dnl earlier GCC or Binutils releases as well. +AC_CACHE_CHECK([if the toolchain is sufficient to build static PIE on LoongArch], +libc_cv_static_pie_on_loongarch, [ + cat > conftest.S << EOF +.global _start +.type _start, @function +_start: + li.w \$a7, 93 + /* This ensures the assembler supports explicit reloc. */ + pcalau12i \$a0, %pc_hi20(x) + ld.w \$a0, \$a0, %pc_lo12(x) + syscall 0 + +.data +x: + .word 0 + /* This should produce an R_LARCH_RELATIVE in the static PIE. */ + .dword _start +EOF + libc_cv_static_pie_on_loongarch=no + if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -static-pie -nostdlib -fPIE -o conftest conftest.S]) \ + && AC_TRY_COMMAND([LC_ALL=C $READELF -Wr conftest | grep -q R_LARCH_RELATIVE]) + then + libc_cv_static_pie_on_loongarch=yes + fi + rm -rf conftest.*]) + +if test "$libc_cv_static_pie_on_loongarch" = yes; then + AC_DEFINE(SUPPORT_STATIC_PIE) +fi diff --git a/sysdeps/loongarch/start.S b/sysdeps/loongarch/start.S index e66af16d57..05cabd9b96 100644 --- a/sysdeps/loongarch/start.S +++ b/sysdeps/loongarch/start.S @@ -60,9 +60,17 @@ ENTRY (ENTRY_POINT) cfi_undefined (1) or a5, a0, zero /* rtld_fini */ +#if defined(PIC) && !defined(SHARED) +/* For static PIE, the GOT cannot be used in _start because the GOT entries are + offsets instead of real addresses before __libc_start_main. */ +# define LA la.pcrel +#else /* We must get symbol main through GOT table, since main may not be local. For instance: googletest defines main in dynamic library. */ - la.got a0, t0, main +# define LA la.got +#endif + + LA a0, t0, main REG_L a1, sp, 0 ADDI a2, sp, SZREG @@ -73,9 +81,9 @@ ENTRY (ENTRY_POINT) move a4, zero /* used to be fini */ or a6, sp, zero /* stack_end */ - la.got ra, t0, __libc_start_main + LA ra, t0, __libc_start_main jirl ra, ra, 0 - la.got ra, t0, abort + LA ra, t0, abort jirl ra, ra, 0 END (ENTRY_POINT) |