Commit 5a205a32 authored by Vineet Gupta's avatar Vineet Gupta
Browse files

ARC: dw2 unwind: add infrastructure for adding cfi pseudo ops to asm 



1. detect whether binutils supports the cfi pseudo ops
2. define conditional macros to generate the ops
3. define new ENTRY_CFI/END_CFI to annotate hand asm code.
   - Needed because we don't want to emit dwarf info in general ENTRY/END
     used by lowest level trap/exception/interrutp handlers as unwinder
     gets confused trying to unwind out of them. We want unwinder to
     instead stop when it hits onfo those routines
   - These provide minimal start/end cfi ops assuming routine doesn't
     touch stack memory/regs

Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
parent 2dad1122

arch/arc/Makefile

+2 −1
Original line number Diff line number Diff line
@@ -65,7 +65,8 @@ endif 


endif



cflags-$(CONFIG_ARC_DW2_UNWIND)		+= -fasynchronous-unwind-tables

cfi := $(call as-instr,.cfi_startproc\n.cfi_endproc,-DARC_DW2_UNWIND_AS_CFI)

cflags-$(CONFIG_ARC_DW2_UNWIND)		+= -fasynchronous-unwind-tables $(cfi)



ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE

# Generic build system uses -O2, we want -O3

arch/arc/include/asm/dwarf.h

0 → 100644
+38 −0
Original line number Diff line number Diff line 
/*

 * Copyright (C) 2016-17 Synopsys, Inc. (www.synopsys.com)

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */



#ifndef _ASM_ARC_DWARF_H

#define _ASM_ARC_DWARF_H



#ifdef __ASSEMBLY__



#ifdef ARC_DW2_UNWIND_AS_CFI



#define CFI_STARTPROC	.cfi_startproc

#define CFI_ENDPROC	.cfi_endproc

#define CFI_DEF_CFA	.cfi_def_cfa

#define CFI_REGISTER	.cfi_register

#define CFI_REL_OFFSET	.cfi_rel_offset

#define CFI_UNDEFINED	.cfi_undefined



#else



#define CFI_IGNORE	#



#define CFI_STARTPROC	CFI_IGNORE

#define CFI_ENDPROC	CFI_IGNORE

#define CFI_DEF_CFA	CFI_IGNORE

#define CFI_REGISTER	CFI_IGNORE

#define CFI_REL_OFFSET	CFI_IGNORE

#define CFI_UNDEFINED	CFI_IGNORE



#endif	/* !ARC_DW2_UNWIND_AS_CFI */



#endif	/* __ASSEMBLY__ */



#endif	/* _ASM_ARC_DWARF_H */

arch/arc/include/asm/linkage.h

+12 −0
Original line number Diff line number Diff line
@@ -9,6 +9,8 @@ 
#ifndef __ASM_LINKAGE_H

#define __ASM_LINKAGE_H



#include <asm/dwarf.h>



#ifdef __ASSEMBLY__



#define ASM_NL		 `	/* use '`' to mark new line in macro */
@@ -32,6 +34,16 @@ 
#endif

.endm



#define ENTRY_CFI(name)		\

	.globl name ASM_NL	\

	ALIGN ASM_NL 		\

	name: ASM_NL		\

	CFI_STARTPROC ASM_NL



#define END_CFI(name) 		\

	CFI_ENDPROC ASM_NL	\

	.size name, .-name



#else	/* !__ASSEMBLY__ */



#ifdef CONFIG_ARC_HAS_ICCM

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