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git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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
-6
-6
tools/include/nolibc/arch-mips.h
-6
tools/include/nolibc/arch-mips.h
···
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__asm__ volatile (
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".set push\n"
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".set noreorder\n"
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"bal 1f\n" /* prime $ra for .cpload */
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"nop\n"
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"1:\n"
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".cpload $ra\n"
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"move $a0, $sp\n" /* save stack pointer to $a0, as arg1 of _start_c */
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"addiu $sp, $sp, -4\n" /* space for .cprestore to store $gp */
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".cprestore 0\n"
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"li $t0, -8\n"
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"and $sp, $sp, $t0\n" /* $sp must be 8-byte aligned */
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"addiu $sp, $sp, -16\n" /* the callee expects to save a0..a3 there */