diff options
Diffstat (limited to 'gcc/doc/tm.texi')
| -rw-r--r-- | gcc/doc/tm.texi | 43 |
1 files changed, 31 insertions, 12 deletions
diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi index 52697e157b6..670b5a237c2 100644 --- a/gcc/doc/tm.texi +++ b/gcc/doc/tm.texi @@ -6190,19 +6190,38 @@ instructions do. @cindex output of assembler code @c prevent bad page break with this line -This describes the overall framework of an assembler file. +This describes the overall framework of an assembly file. + +@deftypefn {Target Hook} void TARGET_ASM_FILE_START () +@findex default_file_start +Output to @code{asm_out_file} any text which the assembler expects to +find at the beginning of a file. The default behavior is controlled +by two flags, documented below. Unless your target's assembler is +quite unusual, if you override the default, you should call +@code{default_file_start} at some point in your target hook. This +lets other target files rely on these variables. +@end deftypefn -@table @code -@findex ASM_FILE_START -@item ASM_FILE_START (@var{stream}) -A C expression which outputs to the stdio stream @var{stream} -some appropriate text to go at the start of an assembler file. - -Normally this macro is defined to output a line containing -@samp{#NO_APP}, which is a comment that has no effect on most -assemblers but tells the GNU assembler that it can save time by not -checking for certain assembler constructs. -@end table +@deftypevr {Target Hook} bool TARGET_ASM_FILE_START_APP_OFF +If this flag is true, the text of the macro @code{ASM_APP_OFF} will be +printed as the very first line in the assembly file, unless +@option{-fverbose-asm} is in effect. (If that macro has been defined +to the empty string, this variable has no effect.) With the normal +definition of @code{ASM_APP_OFF}, the effect is to notify the GNU +assembler that it need not bother stripping comments or extra +whitespace from its input. This allows it to work a bit faster. + +The default is false. You should not set it to true unless you have +verified that your port does not generate any extra whitespace or +comments that will cause GAS to issue errors in NO_APP mode. +@end deftypevr + +@deftypevr {Target Hook} bool TARGET_ASM_FILE_START_FILE_DIRECTIVE +If this flag is true, @code{output_file_directive} will be called +for the primary source file, immediately after printing +@code{ASM_APP_OFF} (if that is enabled). Most ELF assemblers expect +this to be done. The default is false. +@end deftypevr @deftypefn {Target Hook} void TARGET_ASM_FILE_END () Output to @code{asm_out_file} any text which the assembler expects |