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Re: RFC: Patch to allow spill slot alignment greater than the stack alignment

On 10/06/2015 08:02 PM, Steve Ellcey wrote:

If I remove that and I change Rule #16 to handle an AND with a register
I get odd looking .cfi stuff.  The AND instruction (which is marked with
RTX_FRAME_RELATED) seems to generate these cfi_escape macros:

	.cfi_escape 0x10,0x1f,0x2,0x8e,0x7c
	.cfi_escape 0x10,0x1e,0x2,0x8e,0x78
	.cfi_escape 0x10,0xc,0x2,0x8e,0x74

which are meaningless to me.
Possibly something generating a DW_CFA_expression, which then gets expanded as .cfi_escape sequences. Have a look at reg_save, there's code conditional on stack_realign that does that. Or put a breakpoint anywhere in dwarf2cfi that makes a .cfi_escape to see where it's coming from. 

As HJ says, fix readelf first to help you dump the unwind info.


Bernd
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