@@ -141,6 +141,9 @@
/* LOONGARCH floating-point ABI for ld.so. */
#undef LOONGARCH_ABI_FRLEN
+/* Define whether ARM used hard-float and support VFPvX-D32. */
+#undef HAVE_ARM_PCS_VFP_D32
+
/* Linux specific: minimum supported kernel version. */
#undef __LINUX_KERNEL_VERSION
@@ -3056,10 +3056,6 @@ $(objpfx)tst-gnu2-tls2.out: \
$(objpfx)tst-gnu2-tls2mod2.so
ifeq (yes,$(have-mtls-dialect-gnu2))
-# This test fails if dl_tlsdesc_dynamic doesn't preserve all caller-saved
-# registers. See https://sourceware.org/bugzilla/show_bug.cgi?id=31372
-test-xfail-tst-gnu2-tls2 = yes
-
CFLAGS-tst-tlsgap-mod0.c += -mtls-dialect=gnu2
CFLAGS-tst-tlsgap-mod1.c += -mtls-dialect=gnu2
CFLAGS-tst-tlsgap-mod2.c += -mtls-dialect=gnu2
@@ -27,6 +27,10 @@ extern struct tls *apply_tls (struct tls *);
/* An architecture can define them to verify that clobber caller-saved
registers aren't changed by the implicit TLSDESC call. */
+#ifndef INIT_TLSDESC_CALL
+# define INIT_TLSDESC_CALL()
+#endif
+
#ifndef BEFORE_TLSDESC_CALL
# define BEFORE_TLSDESC_CALL()
#endif
@@ -16,13 +16,14 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include "tst-gnu2-tls2.h"
+#include <tst-gnu2-tls2.h>
__thread struct tls tls_var0 __attribute__ ((visibility ("hidden")));
struct tls *
apply_tls (struct tls *p)
{
+ INIT_TLSDESC_CALL ();
BEFORE_TLSDESC_CALL ();
tls_var0 = *p;
struct tls *ret = &tls_var0;
@@ -16,13 +16,14 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include "tst-gnu2-tls2.h"
+#include <tst-gnu2-tls2.h>
__thread struct tls tls_var1[100] __attribute__ ((visibility ("hidden")));
struct tls *
apply_tls (struct tls *p)
{
+ INIT_TLSDESC_CALL ();
BEFORE_TLSDESC_CALL ();
tls_var1[1] = *p;
struct tls *ret = &tls_var1[1];
@@ -16,13 +16,14 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include "tst-gnu2-tls2.h"
+#include <tst-gnu2-tls2.h>
__thread struct tls tls_var2 __attribute__ ((visibility ("hidden")));
struct tls *
apply_tls (struct tls *p)
{
+ INIT_TLSDESC_CALL ();
BEFORE_TLSDESC_CALL ();
tls_var2 = *p;
struct tls *ret = &tls_var2;
@@ -187,6 +187,38 @@ else
default-abi = soft"
fi
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether VFP supports 32 registers" >&5
+printf %s "checking whether VFP supports 32 registers... " >&6; }
+if test ${libc_cv_arm_pcs_vfp_d32+y}
+then :
+ printf %s "(cached) " >&6
+else $as_nop
+
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h. */
+
+void foo (void)
+{
+ asm volatile ("vldr d16,=17" : : : "d16");
+}
+
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"
+then :
+ libc_cv_arm_pcs_vfp_d32=yes
+else $as_nop
+ libc_cv_arm_pcs_vfp_d32=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
+fi
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $libc_cv_arm_pcs_vfp_d32" >&5
+printf "%s\n" "$libc_cv_arm_pcs_vfp_d32" >&6; }
+if test "$libc_cv_arm_pcs_vfp_d32" = yes ;
+then
+ printf "%s\n" "#define HAVE_ARM_PCS_VFP_D32 1" >>confdefs.h
+
+fi
+
{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether PC-relative relocs in movw/movt work properly" >&5
printf %s "checking whether PC-relative relocs in movw/movt work properly... " >&6; }
if test ${libc_cv_arm_pcrel_movw+y}
@@ -21,6 +21,21 @@ else
LIBC_CONFIG_VAR([default-abi], [soft])
fi
+AC_CACHE_CHECK([whether VFP supports 32 registers],
+ libc_cv_arm_pcs_vfp_d32, [
+AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
+void foo (void)
+{
+ asm volatile ("vldr d16,=17" : : : "d16");
+}
+]])],
+ [libc_cv_arm_pcs_vfp_d32=yes],
+ [libc_cv_arm_pcs_vfp_d32=no])])
+if test "$libc_cv_arm_pcs_vfp_d32" = yes ;
+then
+ AC_DEFINE(HAVE_ARM_PCS_VFP_D32)
+fi
+
AC_CACHE_CHECK([whether PC-relative relocs in movw/movt work properly],
libc_cv_arm_pcrel_movw, [
cat > conftest.s <<\EOF
@@ -19,6 +19,7 @@
#include <sysdep.h>
#include <arm-features.h>
#include <tls.h>
+#include <rtld-global-offsets.h>
#include "tlsdesc.h"
.text
@@ -83,14 +84,20 @@ _dl_tlsdesc_dynamic(struct tlsdesc *tdp)
.align 2
_dl_tlsdesc_dynamic:
/* Our calling convention is to clobber r0, r1 and the processor
- flags. All others that are modified must be saved */
- eabi_save ({r2,r3,r4,lr})
- push {r2,r3,r4,lr}
- cfi_adjust_cfa_offset (16)
+ flags. All others that are modified must be saved. r5 is
+ used as the hwcap value to avoid reload after __tls_get_Addr
+ call. If required we will save the vector register on the slow
+ patch if required. */
+ eabi_save ({r2,r3,r4,r5,ip,lr})
+ push {r2,r3,r4,r5,ip,lr}
+ cfi_adjust_cfa_offset (24)
cfi_rel_offset (r2,0)
cfi_rel_offset (r3,4)
cfi_rel_offset (r4,8)
- cfi_rel_offset (lr,12)
+ cfi_rel_offset (r5,12)
+ cfi_rel_offset (ip,16)
+ cfi_rel_offset (lr,20)
+
ldr r1, [r0] /* td */
GET_TLS (lr)
mov r4, r0 /* r4 = tp */
@@ -113,22 +120,69 @@ _dl_tlsdesc_dynamic:
rsbne r0, r4, r3
bne 2f
1: mov r0, r1
+
+ /* Load the hwcap to check for vector support. */
+ ldr r2, 3f
+ ldr r1, .Lrtld_global_ro
+0: add r2, pc, r2
+ ldr r2, [r2, r1]
+ ldr r5, [r2, #RTLD_GLOBAL_RO_DL_HWCAP_OFFSET]
+
+#ifdef __SOFTFP__
+ tst r5, #HWCAP_ARM_VFP
+ beq .Lno_vfp
+#endif
+
+ /* Store the VFP registers. Don't use VFP instructions directly
+ because this code is used in non-VFP multilibs. */
+#define VFP_STACK_REQ (32*8 + 8)
+ sub sp, sp, VFP_STACK_REQ
+ cfi_adjust_cfa_offset (VFP_STACK_REQ)
+ mov r3, sp
+ .inst 0xeca30b20 /* vstmia r3!, {d0-d15} */
+ tst r5, #HWCAP_ARM_VFPD32
+ beq 4f
+ .inst 0xece30b20 /* vstmia r3!, {d16-d31} */
+ /* Store the floating-point status register. */
+4: .inst 0xeef12a10 /* vmrs r2, fpscr */
+ str r2, [r3]
+.Lno_vfp:
bl __tls_get_addr
rsb r0, r4, r0
+#ifdef __SOFTFP__
+ tst r5, #HWCAP_ARM_VFP
+ beq 2f
+#endif
+ mov r3, sp
+ .inst 0xecb30b20 /* vldmia r3!, {d0-d15} */
+ tst r5, #HWCAP_ARM_VFPD32
+ beq 5f
+ .inst 0xecf30b20 /* vldmia r3!, {d16-d31} */
+ ldr r4, [r3]
+5: .inst 0xeee14a10 /* vmsr fpscr, r4 */
+ add sp, sp, VFP_STACK_REQ
+ cfi_adjust_cfa_offset (-VFP_STACK_REQ)
+
2:
#if ((defined (__ARM_ARCH_4T__) && defined (__THUMB_INTERWORK__)) \
|| defined (ARM_ALWAYS_BX))
- pop {r2,r3,r4, lr}
- cfi_adjust_cfa_offset (-16)
+ pop {r2,r3,r4,r5,ip, lr}
+ cfi_adjust_cfa_offset (-20)
cfi_restore (lr)
+ cfi_restore (ip)
+ cfi_restore (r5)
cfi_restore (r4)
cfi_restore (r3)
cfi_restore (r2)
bx lr
#else
- pop {r2,r3,r4, pc}
+ pop {r2,r3,r4,r5,ip, pc}
#endif
eabi_fnend
cfi_endproc
.size _dl_tlsdesc_dynamic, .-_dl_tlsdesc_dynamic
+
+3: .long _GLOBAL_OFFSET_TABLE_ - 0b - PC_OFS
+.Lrtld_global_ro:
+ .long C_SYMBOL_NAME(_rtld_global_ro)(GOT)
#endif /* SHARED */
new file mode 100644
@@ -0,0 +1,96 @@
+/* Test TLSDESC relocation. ARM version.
+ Copyright (C) 2024 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <sys/auxv.h>
+#include <string.h>
+#include <stdlib.h>
+#include <endian.h>
+
+#ifdef HAVE_ARM_PCS_VFP_D32
+# define INIT_TLSDESC_CALL() \
+ unsigned long hwcap = getauxval (AT_HWCAP)
+
+/* Set each vector register to a value from 1 to 32 before the TLS access,
+ dump to memory after TLS access, and compare with the expected values. */
+
+# define BEFORE_TLSDESC_CALL() \
+ if (hwcap & (HWCAP_ARM_VFP | HWCAP_ARM_VFPD32)) \
+ { \
+ asm volatile ("vldr d0,=1" : : : "d0"); \
+ asm volatile ("vldr d1,=2" : : : "d1"); \
+ asm volatile ("vldr d2,=3" : : : "d1"); \
+ asm volatile ("vldr d3,=4" : : : "d3"); \
+ asm volatile ("vldr d4,=5" : : : "d4"); \
+ asm volatile ("vldr d5,=6" : : : "d5"); \
+ asm volatile ("vldr d6,=7" : : : "d6"); \
+ asm volatile ("vldr d7,=8" : : : "d7"); \
+ asm volatile ("vldr d8,=9" : : : "d8"); \
+ asm volatile ("vldr d9,=10" : : : "d9"); \
+ asm volatile ("vldr d10,=11" : : : "d10"); \
+ asm volatile ("vldr d11,=12" : : : "d11"); \
+ asm volatile ("vldr d12,=13" : : : "d12"); \
+ asm volatile ("vldr d13,=14" : : : "d13"); \
+ asm volatile ("vldr d14,=15" : : : "d14"); \
+ asm volatile ("vldr d15,=16" : : : "d15"); \
+ asm volatile ("vldr d16,=17" : : : "d16"); \
+ asm volatile ("vldr d17,=18" : : : "d17"); \
+ asm volatile ("vldr d18,=19" : : : "d18"); \
+ asm volatile ("vldr d19,=20" : : : "d19"); \
+ asm volatile ("vldr d20,=21" : : : "d20"); \
+ asm volatile ("vldr d21,=22" : : : "d21"); \
+ asm volatile ("vldr d22,=23" : : : "d22"); \
+ asm volatile ("vldr d23,=24" : : : "d23"); \
+ asm volatile ("vldr d24,=25" : : : "d24"); \
+ asm volatile ("vldr d25,=26" : : : "d25"); \
+ asm volatile ("vldr d26,=27" : : : "d26"); \
+ asm volatile ("vldr d27,=28" : : : "d27"); \
+ asm volatile ("vldr d28,=29" : : : "d28"); \
+ asm volatile ("vldr d29,=30" : : : "d29"); \
+ asm volatile ("vldr d30,=31" : : : "d30"); \
+ asm volatile ("vldr d31,=32" : : : "d31"); \
+ }
+
+# define VFP_STACK_REQ (32*8)
+# if __BYTE_ORDER == __BIG_ENDIAN
+# define DISP 7
+# else
+# define DISP 0
+# endif
+
+# define AFTER_TLSDESC_CALL() \
+ if (hwcap & HWCAP_ARM_VFP) \
+ { \
+ char vfp[VFP_STACK_REQ]; \
+ asm volatile ("vstmia %0, {d0-d15}\n" \
+ "vstmia %1, {d16-d31}\n" \
+ : \
+ : "r" (vfp), "r" (vfp + 128) \
+ : "memory"); \
+ \
+ char expected[VFP_STACK_REQ]; \
+ memset (expected, 0, sizeof expected); \
+ for (int i = 0; i < 32; ++i) \
+ expected[i * 8 + DISP] = i + 1; \
+ \
+ if (memcmp (vfp, expected, VFP_STACK_REQ) != 0) \
+ abort (); \
+ }
+#endif
+
+#include_next <tst-gnu2-tls2.h>
ARM _dl_tlsdesc_dynamic slow path shows two issues: * The ip/r12 is defined by AAPCS as a scratch register, and gcc is used to save the stack pointer before on some function calls. So it should also be saved/restored as well. It fixes the tst-gnu2-tls2. * None of the possible VFP registers are saved/restored. ARM has the additional complexity to have different VFP bank sizes (depending of VFP support by the chip). The tst-gnu2-tls2 test is extended to check for VFP registers, although only for HWCAP_ARM_VFP | HWCAP_ARM_VFPD32. Different than setcontext, this does not have HWCAP_ARM_IWMMXT (I don't have a way to properly test it and it is almost a decade since newer hardware was released). With this patch there is no need to mark tst-gnu2-tls2 as XFAIL. Checked on arm-linux-gnueabihf. --- config.h.in | 3 ++ elf/Makefile | 4 -- elf/tst-gnu2-tls2.h | 4 ++ elf/tst-gnu2-tls2mod0.c | 3 +- elf/tst-gnu2-tls2mod1.c | 3 +- elf/tst-gnu2-tls2mod2.c | 3 +- sysdeps/arm/configure | 32 +++++++++++++ sysdeps/arm/configure.ac | 15 ++++++ sysdeps/arm/dl-tlsdesc.S | 70 +++++++++++++++++++++++---- sysdeps/arm/tst-gnu2-tls2.h | 96 +++++++++++++++++++++++++++++++++++++ 10 files changed, 218 insertions(+), 15 deletions(-) create mode 100644 sysdeps/arm/tst-gnu2-tls2.h