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| author |  Willy Tarreau <w@1wt.eu>
| 2023-01-10 08:24:30 +0100 |
|---|---|---|
| committer |  Paul E. McKenney <paulmck@kernel.org>
| 2023-01-10 13:33:56 -0800 |
| commit | d01869cf1ee4ad6e02e853062eeced883b3b4504 (patch) | |
| tree | eafb6dcc521cf6a4e66796d5c745b149ab6bb6b7 /tools/include | |
| parent | tools/nolibc: add auxiliary vector retrieval for riscv (diff) | |
| download | linux-d01869cf1ee4ad6e02e853062eeced883b3b4504.tar.gz linux-d01869cf1ee4ad6e02e853062eeced883b3b4504.tar.bz2 linux-d01869cf1ee4ad6e02e853062eeced883b3b4504.zip | |
tools/nolibc: add auxiliary vector retrieval for mips
In the _start block we now iterate over envp to find the auxiliary
vector after the NULL. The pointer is saved into an _auxv variable
that is marked as weak so that it's accessible from multiple units.
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'tools/include')
| -rw-r--r-- | tools/include/nolibc/arch-mips.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/tools/include/nolibc/arch-mips.h b/tools/include/nolibc/arch-mips.h index 7d22f7bc38b3..bf83432d23ed 100644 --- a/tools/include/nolibc/arch-mips.h +++ b/tools/include/nolibc/arch-mips.h @@ -177,6 +177,7 @@ struct sys_stat_struct { }) char **environ __attribute__((weak)); +const unsigned long *_auxv __attribute__((weak)); /* startup code, note that it's called __start on MIPS */ void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __start(void) @@ -196,6 +197,16 @@ void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __start(void) "lui $a3, %hi(environ)\n" // load environ into a3 (hi) "addiu $a3, %lo(environ)\n" // load environ into a3 (lo) "sw $a2,($a3)\n" // store envp(a2) into environ + + "move $t0, $a2\n" // iterate t0 over envp, look for NULL + "0:" // do { + "lw $a3, ($t0)\n" // a3=*(t0); + "bne $a3, $0, 0b\n" // } while (a3); + "addiu $t0, $t0, 4\n" // delayed slot: t0+=4; + "lui $a3, %hi(_auxv)\n" // load _auxv into a3 (hi) + "addiu $a3, %lo(_auxv)\n" // load _auxv into a3 (lo) + "sw $t0, ($a3)\n" // store t0 into _auxv + "li $t0, -8\n" "and $sp, $sp, $t0\n" // sp must be 8-byte aligned "addiu $sp,$sp,-16\n" // the callee expects to save a0..a3 there! |