From 34b4624b04fc8f038b2c329ca7560197320615b4 Mon Sep 17 00:00:00 2001 From: Fangrui Song Date: Wed, 18 Aug 2021 10:01:31 -0700 Subject: [PATCH] riscv: Drop reliance on _GLOBAL_OFFSET_TABLE_[0] &__ehdr_start is a better way to get the load address. This is similar to commits b37b75d269883a2c553bb7019a813094eb4e2dd1 (x86-64) and 43d06ed218fc8be58987bdfd00e21e5720f0b862 (aarch64). Reviewed-by: Palmer Dabbelt --- sysdeps/riscv/dl-machine.h | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) diff --git a/sysdeps/riscv/dl-machine.h b/sysdeps/riscv/dl-machine.h index aedf69fcdd..5b0746175c 100644 --- a/sysdeps/riscv/dl-machine.h +++ b/sysdeps/riscv/dl-machine.h @@ -76,27 +76,26 @@ elf_machine_matches_host (const ElfW(Ehdr) *ehdr) return 1; } +/* Return the run-time load address of the shared object. */ +static inline ElfW(Addr) +elf_machine_load_address (void) +{ + extern const ElfW(Ehdr) __ehdr_start attribute_hidden; + return (ElfW(Addr)) &__ehdr_start; +} + /* Return the link-time address of _DYNAMIC. */ static inline ElfW(Addr) elf_machine_dynamic (void) { - extern ElfW(Addr) _GLOBAL_OFFSET_TABLE_ __attribute__ ((visibility ("hidden"))); - return _GLOBAL_OFFSET_TABLE_; + extern ElfW(Dyn) _DYNAMIC[] attribute_hidden; + return (ElfW(Addr)) _DYNAMIC - elf_machine_load_address (); } #define STRINGXP(X) __STRING (X) #define STRINGXV(X) STRINGV_ (X) #define STRINGV_(...) # __VA_ARGS__ -/* Return the run-time load address of the shared object. */ -static inline ElfW(Addr) -elf_machine_load_address (void) -{ - ElfW(Addr) load_addr; - asm ("lla %0, _DYNAMIC" : "=r" (load_addr)); - return load_addr - elf_machine_dynamic (); -} - /* Initial entry point code for the dynamic linker. The C function `_dl_start' is the real entry point; its return value is the user program's entry point. */