32 lines
849 B
ArmAsm
32 lines
849 B
ArmAsm
/* */
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/* alloca() - allocate space on the stack Author: Kees J. Bot */
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/* 2 Dec 1993 */
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#include <machine/asm.h>
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ENTRY(alloca)
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#if __ACK__
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pop %ecx /* Return address */
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pop %eax /* Bytes to allocate */
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addl $2*4+3, %eax /* Add space for two saved register variables */
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andb $0xF8, %al /* Align */
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movl %esp, %ebx /* Keep current esp */
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subl %eax, %esp /* Lower stack */
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movl %esp, %eax /* Return value */
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push 4(%ebx) /* Push what is probably the saved esi */
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push (%ebx) /* Saved edi */
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/* Now ACK can still do: */
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/* pop edi; pop esi; leave; ret */
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push %eax /* Dummy argument */
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jmp *%ecx
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#else
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pop %ecx /* Return address */
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pop %eax /* Bytes to allocate */
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addl $3, %eax
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andb $0xF8, %al /* Align */
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subl %eax, %esp /* Lower stack */
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movl %esp, %eax /* Return value */
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push %eax /* Dummy argument */
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jmp *%ecx
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#endif
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