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| author | Vineet Gupta <vgupta@synopsys.com> | 2016-09-17 02:23:26 +0200 |
|---|---|---|
| committer | Vineet Gupta <vgupta@synopsys.com> | 2016-09-30 23:48:22 +0200 |
| commit | 5a205a32ffccf6e720a2d2b3aee44b16619016a6 (patch) | |
| tree | 9ff1460c48ecbcc382405826ff53c5329bd5a9dd | |
| parent | ARC: entry: make ret_from_system_call local label (diff) | |
| download | linux-5a205a32ffccf6e720a2d2b3aee44b16619016a6.tar.xz linux-5a205a32ffccf6e720a2d2b3aee44b16619016a6.zip | |
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: Vineet Gupta <vgupta@synopsys.com>
| -rw-r--r-- | arch/arc/Makefile | 3 | ||||
| -rw-r--r-- | arch/arc/include/asm/dwarf.h | 38 | ||||
| -rw-r--r-- | arch/arc/include/asm/linkage.h | 12 |
3 files changed, 52 insertions, 1 deletions
diff --git a/arch/arc/Makefile b/arch/arc/Makefile index a2a6a4614241..aa82d13d4213 100644 --- a/arch/arc/Makefile +++ b/arch/arc/Makefile @@ -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 diff --git a/arch/arc/include/asm/dwarf.h b/arch/arc/include/asm/dwarf.h new file mode 100644 index 000000000000..bb7bdbc59a44 --- /dev/null +++ b/arch/arc/include/asm/dwarf.h @@ -0,0 +1,38 @@ +/* + * 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 */ diff --git a/arch/arc/include/asm/linkage.h b/arch/arc/include/asm/linkage.h index 5faad17118b4..b29f1a9fd6f7 100644 --- a/arch/arc/include/asm/linkage.h +++ b/arch/arc/include/asm/linkage.h @@ -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 |