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| author | H.J. Lu <hjl.tools@gmail.com> | 2024-02-26 06:37:03 -0800 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2024-02-28 09:02:56 -0800 |
| commit | 0aac205a814a8511e98d02b91a8dc908f1c53cde (patch) | |
| tree | e9ad8dfa06abd2f6d9b521bb95e9b7cfaa0d7de7 /sysdeps/x86_64/dl-trampoline.h | |
| parent | e6350be7e9cae8f71c96c1f06eab61b9acb227c8 (diff) | |
| download | glibc-0aac205a814a8511e98d02b91a8dc908f1c53cde.tar.gz glibc-0aac205a814a8511e98d02b91a8dc908f1c53cde.tar.xz glibc-0aac205a814a8511e98d02b91a8dc908f1c53cde.zip | |
x86: Update _dl_tlsdesc_dynamic to preserve caller-saved registers
Compiler generates the following instruction sequence for GNU2 dynamic TLS access: leaq tls_var@TLSDESC(%rip), %rax call *tls_var@TLSCALL(%rax) or leal tls_var@TLSDESC(%ebx), %eax call *tls_var@TLSCALL(%eax) CALL instruction is transparent to compiler which assumes all registers, except for EFLAGS and RAX/EAX, are unchanged after CALL. When _dl_tlsdesc_dynamic is called, it calls __tls_get_addr on the slow path. __tls_get_addr is a normal function which doesn't preserve any caller-saved registers. _dl_tlsdesc_dynamic saved and restored integer caller-saved registers, but didn't preserve any other caller-saved registers. Add _dl_tlsdesc_dynamic IFUNC functions for FNSAVE, FXSAVE, XSAVE and XSAVEC to save and restore all caller-saved registers. This fixes BZ #31372. Add GLRO(dl_x86_64_runtime_resolve) with GLRO(dl_x86_tlsdesc_dynamic) to optimize elf_machine_runtime_setup. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
Diffstat (limited to 'sysdeps/x86_64/dl-trampoline.h')
| -rw-r--r-- | sysdeps/x86_64/dl-trampoline.h | 34 |
1 files changed, 1 insertions, 33 deletions
diff --git a/sysdeps/x86_64/dl-trampoline.h b/sysdeps/x86_64/dl-trampoline.h index f55c6ea040..d9ccfb40d4 100644 --- a/sysdeps/x86_64/dl-trampoline.h +++ b/sysdeps/x86_64/dl-trampoline.h @@ -27,39 +27,7 @@ # undef LOCAL_STORAGE_AREA # undef BASE -# if (STATE_SAVE_ALIGNMENT % 16) != 0 -# error STATE_SAVE_ALIGNMENT must be multiple of 16 -# endif - -# if (STATE_SAVE_OFFSET % STATE_SAVE_ALIGNMENT) != 0 -# error STATE_SAVE_OFFSET must be multiple of STATE_SAVE_ALIGNMENT -# endif - -# if DL_RUNTIME_RESOLVE_REALIGN_STACK -/* Local stack area before jumping to function address: RBX. */ -# define LOCAL_STORAGE_AREA 8 -# define BASE rbx -# ifdef USE_FXSAVE -/* Use fxsave to save XMM registers. */ -# define REGISTER_SAVE_AREA (512 + STATE_SAVE_OFFSET) -# if (REGISTER_SAVE_AREA % 16) != 0 -# error REGISTER_SAVE_AREA must be multiple of 16 -# endif -# endif -# else -# ifndef USE_FXSAVE -# error USE_FXSAVE must be defined -# endif -/* Use fxsave to save XMM registers. */ -# define REGISTER_SAVE_AREA (512 + STATE_SAVE_OFFSET + 8) -/* Local stack area before jumping to function address: All saved - registers. */ -# define LOCAL_STORAGE_AREA REGISTER_SAVE_AREA -# define BASE rsp -# if (REGISTER_SAVE_AREA % 16) != 8 -# error REGISTER_SAVE_AREA must be odd multiple of 8 -# endif -# endif +# include "dl-trampoline-state.h" .globl _dl_runtime_resolve .hidden _dl_runtime_resolve |