* dwarf2dbg.c: Include safe-ctype.h.

        (DWARF2_LINE_OPCODE_BASE): Bump to 13.
        (current): Initialize.
        (dwarf2_emit_insn): Clear DWARF2_FLAG_BASIC_BLOCK,
        DWARF2_FLAG_PROLOGUE_END, DWARF2_FLAG_EPILOGUE_BEGIN.
        (dwarf2_directive_file): Cope with invalid filename.
        (dwarf2_directive_loc): Add handling for basic_block, prologue_end,
        epilogue_begin, is_stmt, isa.
        (emit_inc_line_addr): Move line_delta == 0, addr_delta == 0 special
        case down lower.
        (process_entries): Handle isa, DWARF2_FLAG_PROLOGUE_END,
        and DWARF2_FLAG_EPILOGUE_BEGIN.
        (out_debug_line): Emit sizes for DW_LNS_set_prologue_end,
        DW_LNS_set_epilogue_begin, DW_LNS_set_isa.
        * dwarf2dbg.h (DWARF2_FLAG_IS_STMT): Rename from DWARF2_FLAG_BEGIN_STMT.        (DWARF2_FLAG_BASIC_BLOCK): Rename from DWARF2_FLAG_BEGIN_BLOCK.
        (DWARF2_FLAG_PROLOGUE_END, DWARF2_FLAG_EPILOGUE_BEGIN): New.
        (struct dwarf2_line_info): Add isa member.
        * doc/as.texinfo (LNS directives): New node.

1 files changed, 46 insertions, 1 deletions

diff --git a/gas/doc/as.texinfo b/gas/doc/as.texinfo
index 0721631..e85677d 100644
--- a/gas/doc/as.texinfo
+++ b/gas/doc/as.texinfo
@@ -3745,9 +3745,12 @@ Some machine configurations provide additional directives.
 * Line::                        @code{.line @var{line-number}}
 @end ifclear
 
-* Ln::                          @code{.ln @var{line-number}}
 * Linkonce::			@code{.linkonce [@var{type}]}
 * List::                        @code{.list}
+* Ln::                          @code{.ln @var{line-number}}
+
+* LNS directives::              @code{.file}, @code{.loc}, etc.
+
 * Long::                        @code{.long @var{expressions}}
 @ignore
 * Lsym::                        @code{.lsym @var{symbol}, @var{expression}}
@@ -4049,6 +4052,48 @@ Allows the user to add arbitrary bytes to the unwind info.  One
 might use this to add OS-specific CFI opcodes, or generic CFI
 opcodes that GAS does not yet support.
 
+@node LNS directives
+@section @code{.file @var{fileno} @var{filename}}
+@cindex @code{file} directive
+When emitting dwarf2 line number information @code{.file} assigns filenames
+to the @code{.debug_line} file name table.  The @var{fileno} operand should
+be a unique positive integer to use as the index of the entry in the table.
+The @var{filename} operand is a C string literal.
+
+The detail of filename indicies is exposed to the user because the filename
+table is shared with the @code{.debug_info} section of the dwarf2 debugging
+information, and thus the user must know the exact indicies that table
+entries will have.
+
+@section @code{.loc @var{fileno} @var{lineno} [@var{column}]}
+@cindex @code{loc} directive
+The @code{.loc} directive will add row to the @code{.debug_line} line
+number matrix corresponding to the immediately following assembly
+instruction.  The @var{fileno}, @var{lineno}, and optional @var{column}
+arguments will be applied to the @code{.debug_line} state machine before
+the row is added.
+
+@section @code{.loc basic_block}
+This directive will set the @code{basic_block} register in the
+@code{.debug_line} state machine to @code{true}.
+
+@section @code{.loc prologue_end}
+This directive will set the @code{prologue_end} register in the
+@code{.debug_line} state machine to @code{true}.
+
+@section @code{.loc epilogue_begin}
+This directive will set the @code{epilogue_begin} register in the
+@code{.debug_line} state machine to @code{true}.
+
+@section @code{.loc is_stmt @var{value}}
+This directive will set the @code{epilogue_begin} register in the
+@code{.debug_line} state machine to @code{value}, which must be 
+either 0 or 1.
+
+@section @code{.loc isa @var{value}}
+This directive will set the @code{isa} register in the @code{.debug_line}
+state machine to @var{value}, which must be an unsigned integer.
+
 @node Data
 @section @code{.data @var{subsection}}