source: mainline/uspace/lib/c/arch/ppc32/src/crt0.S

#
# Copyright (c) 2006 Martin Decky
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#include <abi/asmtool.h>

.text

.org 0

## User-space task entry point
#
# r6 contains the PCB pointer
#
SYMBOL(_start)
        #
        # Create the first stack frame.
        #
        li %r3, 0
        stw %r3, 0(%r1)
        stwu %r1, -16(%r1)

        # Pass the PCB pointer to __c_start() as the first argument.
        # The first argument is passed in r3.
        mr %r3, %r6
        bl __c_start