33 lines
659 B
ArmAsm
33 lines
659 B
ArmAsm
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# void swtch(struct context *old, struct context *new);
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#
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# Save current register context in old
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# and then load register context from new.
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.globl swtch
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swtch:
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# Save old registers
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movl 4(%esp), %eax
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popl 0(%eax) # %eip
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movl %esp, 4(%eax)
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movl %ebx, 8(%eax)
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movl %ecx, 12(%eax)
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movl %edx, 16(%eax)
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movl %esi, 20(%eax)
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movl %edi, 24(%eax)
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movl %ebp, 28(%eax)
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# Load new registers
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movl 4(%esp), %eax # not 8(%esp) - popped return address above
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movl 28(%eax), %ebp
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movl 24(%eax), %edi
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movl 20(%eax), %esi
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movl 16(%eax), %edx
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movl 12(%eax), %ecx
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movl 8(%eax), %ebx
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movl 4(%eax), %esp
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pushl 0(%eax) # %eip
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ret
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