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lxdream.org :: lxdream/src/sh4/ia64asm.s
lxdream 0.9.1
released Jun 29
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filename src/sh4/ia64asm.s
changeset 571:9bc09948d0f2
author nkeynes
date Thu Jan 10 08:28:37 2008 +0000 (14 years ago)
branchlxdream-mmu
permissions -rw-r--r--
last change More MMU work in progess. Much better now...
file annotate diff log raw
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# 
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# Scan back through the stack until we hit the currently executing
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# translation block, and find the call return address to that block.
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# 
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# Implementation: iterate back through each stack frame until we find
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# a frame that has a saved %ebp == sh4r (setup by the xlat blocks).
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# The return address is then the stack value immediately before the
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# saved %ebp.
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#
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# At most 8 stack frames are checked, to prevent infinite looping on a
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# corrupt stack.
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.global xlat_get_native_pc
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xlat_get_native_pc:
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	mov %rbp, %rax
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	mov $0x8, %ecx
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	mov $sh4r, %rdx
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frame_loop:
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	test %rax, %rax
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	je frame_not_found
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	cmpq (%rax), %rdx
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	je frame_found
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	sub $0x1, %ecx
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	je frame_not_found
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	movq (%rax), %rax
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	jmp frame_loop
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frame_found:
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	movl 0x4(%rax), %rax
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	ret
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frame_not_found:
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	xor %rax, %rax
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	ret
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