tools/nolibc: MIPS: drop $gp setup

The setup of the global pointer "$gp" register was necessary when the C
entrypoint was called through "jal <symbol>".
However since commit 0daf8c86a451 ("tools/nolibc: mips: load current function to $t9")
"jalr" is used instead which does not require "$gp".

Remove the unnecessary $gp setup, simplifying the code and opening the
road for some other cleanups.

Suggested-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/lkml/alpine.DEB.2.21.2502172208570.65342@angie.orcam.me.uk/
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Tested-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Link: https://lore.kernel.org/r/20250623-nolibc-mips-n32-v3-1-6ae2d89f4259@weissschuh.net

diff --git a/tools/include/nolibc/arch-mips.h b/tools/include/nolibc/arch-mips.h
index 753a8ed2cf695f0b5eac4b5e4d317fdb383ebf93..6d023d9f120301b2d6837c923c142ab2cf87ae5a 100644 (file)
--- a/tools/include/nolibc/arch-mips.h
+++ b/tools/include/nolibc/arch-mips.h
@@ -185,13 +185,7 @@ void __attribute__((weak, noreturn)) __nolibc_entrypoint __no_stack_protector __
        __asm__ volatile (
                ".set push\n"
                ".set noreorder\n"
-               "bal 1f\n"               /* prime $ra for .cpload                            */
-               "nop\n"
-               "1:\n"
-               ".cpload $ra\n"
                "move  $a0, $sp\n"       /* save stack pointer to $a0, as arg1 of _start_c */
-               "addiu $sp, $sp, -4\n"   /* space for .cprestore to store $gp              */
-               ".cprestore 0\n"
                "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        */