1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/sh4/ia64asm.s	Tue Jan 15 11:07:32 2008 +0000
     1.3 @@ -0,0 +1,34 @@
     1.4 +# 
     1.5 +# Scan back through the stack until we hit the currently executing
     1.6 +# translation block, and find the call return address to that block.
     1.7 +# 
     1.8 +# Implementation: iterate back through each stack frame until we find
     1.9 +# a frame that has a saved %ebp == sh4r (setup by the xlat blocks).
    1.10 +# The return address is then the stack value immediately before the
    1.11 +# saved %ebp.
    1.12 +#
    1.13 +# At most 8 stack frames are checked, to prevent infinite looping on a
    1.14 +# corrupt stack.
    1.15 +
    1.16 +.global xlat_get_native_pc
    1.17 +xlat_get_native_pc:
    1.18 +	mov %rbp, %rax
    1.19 +	mov $0x8, %ecx
    1.20 +	mov $sh4r, %rdx
    1.21 +
    1.22 +frame_loop:
    1.23 +	test %rax, %rax
    1.24 +	je frame_not_found
    1.25 +	cmpq (%rax), %rdx
    1.26 +	je frame_found
    1.27 +	sub $0x1, %ecx
    1.28 +	je frame_not_found
    1.29 +	movq (%rax), %rax
    1.30 +	jmp frame_loop
    1.31 +
    1.32 +frame_found:
    1.33 +	movl 0x4(%rax), %rax
    1.34 +	ret
    1.35 +frame_not_found:
    1.36 +	xor %rax, %rax
    1.37 +	ret