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| author | Vineet Gupta <vgupta@synopsys.com> | 2015-11-23 22:30:35 +0530 |
|---|---|---|
| committer | Vineet Gupta <vgupta@synopsys.com> | 2016-09-30 14:48:19 -0700 |
| commit | d040876b4aad0c157c5c95779128b71a121ff27d (patch) | |
| tree | 8efde7afdd04f791d17a0e61008b79c364e7f4c4 /arch/arc/kernel/unwind.c | |
| parent | 94f4fb0841bfa5c1088a1b3a879a65bdd675ecd2 (diff) | |
| download | linux-d040876b4aad0c157c5c95779128b71a121ff27d.tar.gz linux-d040876b4aad0c157c5c95779128b71a121ff27d.tar.bz2 linux-d040876b4aad0c157c5c95779128b71a121ff27d.zip | |
ARC: dw2 unwind: factor CIE specifics for .eh_frame/.debug_frame
This paves way for switching to .eh_frame based unwindiing
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Diffstat (limited to 'arch/arc/kernel/unwind.c')
| -rw-r--r-- | arch/arc/kernel/unwind.c | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/arch/arc/kernel/unwind.c b/arch/arc/kernel/unwind.c index 0587bf121d11..4e5dbe7617a1 100644 --- a/arch/arc/kernel/unwind.c +++ b/arch/arc/kernel/unwind.c @@ -111,6 +111,8 @@ UNW_REGISTER_INFO}; #define DW_EH_PE_indirect 0x80 #define DW_EH_PE_omit 0xff +#define CIE_ID 0xffffffffUL + typedef unsigned long uleb128_t; typedef signed long sleb128_t; @@ -232,6 +234,7 @@ void __init arc_unwind_init(void) static const u32 bad_cie, not_fde; static const u32 *cie_for_fde(const u32 *fde, const struct unwind_table *); +static const u32 *__cie_for_fde(const u32 *fde); static signed fde_pointer_type(const u32 *cie); struct eh_frame_hdr_table_entry { @@ -338,10 +341,9 @@ static void init_unwind_hdr(struct unwind_table *table, for (fde = table->address, tableSize = table->size, n = 0; tableSize; tableSize -= sizeof(*fde) + *fde, fde += 1 + *fde / sizeof(*fde)) { - /* const u32 *cie = fde + 1 - fde[1] / sizeof(*fde); */ - const u32 *cie = (const u32 *)(fde[1]); + const u32 *cie = __cie_for_fde(fde); - if (fde[1] == 0xffffffff) + if (fde[1] == CIE_ID) continue; /* this is a CIE */ ptr = (const u8 *)(fde + 2); header->table[n].start = read_pointer(&ptr, @@ -504,6 +506,16 @@ static sleb128_t get_sleb128(const u8 **pcur, const u8 *end) return value; } +static const u32 *__cie_for_fde(const u32 *fde) +{ + const u32 *cie; + + /* cie = fde + 1 - fde[1] / sizeof(*fde); */ + cie = (u32 *) fde[1]; + + return cie; +} + static const u32 *cie_for_fde(const u32 *fde, const struct unwind_table *table) { const u32 *cie; @@ -511,19 +523,18 @@ static const u32 *cie_for_fde(const u32 *fde, const struct unwind_table *table) if (!*fde || (*fde & (sizeof(*fde) - 1))) return &bad_cie; - if (fde[1] == 0xffffffff) + if (fde[1] == CIE_ID) return ¬_fde; /* this is a CIE */ if ((fde[1] & (sizeof(*fde) - 1))) /* || fde[1] > (unsigned long)(fde + 1) - (unsigned long)table->address) */ return NULL; /* this is not a valid FDE */ - /* cie = fde + 1 - fde[1] / sizeof(*fde); */ - cie = (u32 *) fde[1]; + cie = __cie_for_fde(fde); if (*cie <= sizeof(*cie) + 4 || *cie >= fde[1] - sizeof(*fde) || (*cie & (sizeof(*cie) - 1)) - || (cie[1] != 0xffffffff)) + || (cie[1] != CIE_ID)) return NULL; /* this is not a (valid) CIE */ return cie; } |