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  <jbeulich@suse.com>

	* 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  <jbeulich@suse.com>

	gas/cfi/cfi-label.d, gas/cfi/cfi-label.s: New.
	gas/cfi/cfi.exp: Run new tests.

1 files changed, 1 insertions, 1 deletions

diff --git a/gas/read.c b/gas/read.c
index 7dfc20a..b2d5027 100644
--- a/gas/read.c
+++ b/gas/read.c
@@ -1600,7 +1600,7 @@ s_altmacro (int on)
    If a symbol name could not be read, the routine issues an error
    messages, skips to the end of the line and returns NULL.  */
 
-static char *
+char *
 read_symbol_name (void)
 {
   char * name;