From 696025802ec3273fde5cbf82c215a3d795435c1a Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Mon, 12 Jan 2015 15:24:20 +0100 Subject: gas: allow labeling of CFI instructions When runtime patching code (like e.g. done by the Linux kernel) there may be cases where the set of stack frame alterations differs between unpatched and patched code. Consequently the corresponding unwind data needs patching too. Locating the right places within an FDE, however, is rather cumbersome without a way to insert labels in the resulting section. Hence this patch introduces a new directive, .cfi_label. Note that with the way CFI data gets emitted currently (at the end of the assembly process) this can't support local FB- and dollar-labels. gas/ 2015-01-12 Jan Beulich * gas/dw2gencfi.c (cfi_add_label, dot_cfi_label): New. (cfi_pseudo_table): Add "cfi_label". (output_cfi_insn): Handle CFI_label. (select_cie_for_fde): Als terminate CIE when encountering CFI_label. * dw2gencfi.h (cfi_add_label): Declare. (struct cfi_insn_data): New member "sym_name". (CFI_label): New. * read.c (read_symbol_name): Drop "static". * read.h (read_symbol_name): Declare. gas/testsuite/ 2015-01-12 Jan Beulich gas/cfi/cfi-label.d, gas/cfi/cfi-label.s: New. gas/cfi/cfi.exp: Run new tests. --- gas/dw2gencfi.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'gas/dw2gencfi.h') diff --git a/gas/dw2gencfi.h b/gas/dw2gencfi.h index e80b19e..6e2c50e 100644 --- a/gas/dw2gencfi.h +++ b/gas/dw2gencfi.h @@ -37,6 +37,7 @@ extern void cfi_new_fde (struct symbol *); extern void cfi_end_fde (struct symbol *); extern void cfi_set_return_column (unsigned); extern void cfi_add_advance_loc (struct symbol *); +extern void cfi_add_label (const char *); extern void cfi_add_CFA_offset (unsigned, offsetT); extern void cfi_add_CFA_def_cfa (unsigned, offsetT); @@ -94,6 +95,8 @@ struct cfi_insn_data unsigned reg, encoding; expressionS exp; } ea; + + const char *sym_name; } u; }; @@ -128,5 +131,6 @@ extern struct fde_entry *all_fde_data; #define CFI_escape 0x103 #define CFI_signal_frame 0x104 #define CFI_val_encoded_addr 0x105 +#define CFI_label 0x106 #endif /* DW2GENCFI_H */ -- cgit v1.1