musl/arch/mips/crt_arch.h
Rich Felker 9f26ebded1 fix stack alignment code in mips crt_arch.h
the instruction used to align the stack, "and $sp, $sp, -8", does not
actually exist; it's expanded to 2 instructions using the 'at'
(assembler temporary) register, and thus cannot be used in a branch
delay slot. since alignment mod 16 commutes with subtracting 8, simply
swapping these two operations fixes the problem.

crt1.o was not affected because it's still being generated from a
dedicated asm source file. dlstart.lo was not affected because the
stack pointer it receives is already aligned by the kernel. but
Scrt1.o was affected in cases where the dynamic linker gave it a
misaligned stack pointer.
2015-05-24 23:03:47 -04:00

30 lines
575 B
C

__asm__(
".set push\n"
".set noreorder\n"
".text \n"
".global _" START "\n"
".global " START "\n"
".type _" START ", @function\n"
".type " START ", @function\n"
"_" START ":\n"
"" START ":\n"
" bal 1f \n"
" move $fp, $0 \n"
"2: .gpword 2b \n"
" .gpword " START "_c \n"
".weak _DYNAMIC \n"
".hidden _DYNAMIC \n"
" .gpword _DYNAMIC \n"
"1: lw $gp, 0($ra) \n"
" subu $gp, $ra, $gp \n"
" move $4, $sp \n"
" lw $5, 8($ra) \n"
" addu $5, $5, $gp \n"
" lw $25, 4($ra) \n"
" addu $25, $25, $gp \n"
" and $sp, $sp, -8 \n"
" jalr $25 \n"
" subu $sp, $sp, 16 \n"
".set pop \n"
);