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Diffstat (limited to 'gcc/doc/tm.texi')
| -rw-r--r-- | gcc/doc/tm.texi | 70 |
1 files changed, 47 insertions, 23 deletions
diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi index 4b885113797..12812bd0118 100644 --- a/gcc/doc/tm.texi +++ b/gcc/doc/tm.texi @@ -233,6 +233,19 @@ an example of this. Do not define this macro if it does not need to do anything. +@findex AS_NEEDS_DASH_FOR_PIPED_INPUT +@item AS_NEEDS_DASH_FOR_PIPED_INPUT +Define this macro, with no value, if the driver should give the assembler +an argument consisting of a single dash, @option{-}, to instruct it to +read from its standard input (which will be a pipe connected to the +output of the compiler proper). This argument is given after any +@option{-o} option specifying the name of the output file. + +If you do not define this macro, the assembler is assumed to read its +standard input if given no non-option arguments. If your assembler +cannot read standard input at all, use a @samp{%@{pipe:%e@}} construct; +see @file{mips.h} for instance. + @findex LINK_SPEC @item LINK_SPEC A C string constant that tells the GCC driver program options to @@ -4239,18 +4252,18 @@ the function prologue. Normally, the profiling code comes after. @subsection Permitting tail calls @cindex tail calls -@table @code -@findex FUNCTION_OK_FOR_SIBCALL -@item FUNCTION_OK_FOR_SIBCALL (@var{decl}) -A C expression that evaluates to true if it is ok to perform a sibling -call to @var{decl} from the current function. +@deftypefn {Target Hook} bool TARGET_FUNCTION_OK_FOR_SIBCALL (tree @var{decl}, tree @var{exp}) +True if it is ok to do sibling call optimization for the specified +call expression @var{exp}. @var{decl} will be the called function, +or @code{NULL} if this is an indirect call. It is not uncommon for limitations of calling conventions to prevent tail calls to functions outside the current unit of translation, or -during PIC compilation. Use this macro to enforce these restrictions, +during PIC compilation. The hook is used to enforce these restrictions, as the @code{sibcall} md pattern can not fail, or fall over to a -``normal'' call. -@end table +``normal'' call. The criteria for successful sibling call optimization +may vary greatly between different architectures. +@end deftypefn @node Varargs @section Implementing the Varargs Macros @@ -5413,6 +5426,15 @@ to clear a chunk of memory, or whether some other block clear mechanism will be used. Defaults to 1 if @code{move_by_pieces_ninsns} returns less than @code{CLEAR_RATIO}. +@findex STORE_BY_PIECES_P +@item STORE_BY_PIECES_P (@var{size}, @var{alignment}) +A C expression used to determine whether @code{store_by_pieces} will be +used to set a chunk of memory to a constant value, or whether some other +mechanism will be used. Used by @code{__builtin_memset} when storing +values other than constant zero and by @code{__builtin_strcpy} when +when called with a constant source string. +Defaults to @code{MOVE_BY_PIECES_P}. + @findex USE_LOAD_POST_INCREMENT @item USE_LOAD_POST_INCREMENT (@var{mode}) A C expression used to determine whether a load postincrement is a good @@ -6267,7 +6289,7 @@ responsible for outputting the label definition at the proper place. Here is how to do this: @example -ASM_OUTPUT_INTERNAL_LABEL (@var{file}, "LC", @var{labelno}); +@code{(*targetm.asm_out.internal_label)} (@var{file}, "LC", @var{labelno}); @end example When you output a pool entry specially, you should end with a @@ -6725,11 +6747,11 @@ This macro is not used by @code{output_asm_label}, or the @code{%l} specifier that calls it; the intention is that this macro should be set when it is necessary to output a label differently when its address is being taken. +@end table -@findex ASM_OUTPUT_INTERNAL_LABEL -@item ASM_OUTPUT_INTERNAL_LABEL (@var{stream}, @var{prefix}, @var{num}) -A C statement to output to the stdio stream @var{stream} a label whose -name is made from the string @var{prefix} and the number @var{num}. +@deftypefn {Target Hook} void TARGET_ASM_INTERNAL_LABEL (FILE *@var{stream}, const char *@var{prefix}, unsigned long @var{labelno}) +A function to output to the stdio stream @var{stream} a label whose +name is made from the string @var{prefix} and the number @var{labelno}. It is absolutely essential that these labels be distinct from the labels used for user-level functions and variables. Otherwise, certain programs @@ -6741,12 +6763,11 @@ should be excluded; on many systems, the letter @samp{L} at the beginning of a label has this effect. You should find out what convention your system uses, and follow it. -The usual definition of this macro is as follows: +The default version of this function utilizes ASM_GENERATE_INTERNAL_LABEL. -@example -fprintf (@var{stream}, "L%s%d:\n", @var{prefix}, @var{num}) -@end example +@end deftypefn +@table @code @findex ASM_OUTPUT_DEBUG_LABEL @item ASM_OUTPUT_DEBUG_LABEL (@var{stream}, @var{prefix}, @var{num}) A C statement to output to the stdio stream @var{stream} a debug info @@ -6757,7 +6778,7 @@ systems, branch target labels must be at the beginning of instruction bundles, but debug info labels can occur in the middle of instruction bundles. -If this macro is not defined, then @code{ASM_OUTPUT_INTERNAL_LABEL} will be +If this macro is not defined, then @code{(*targetm.asm_out.internal_label)} will be used. @findex ASM_GENERATE_INTERNAL_LABEL @@ -6766,7 +6787,7 @@ A C statement to store into the string @var{string} a label whose name is made from the string @var{prefix} and the number @var{num}. This string, when output subsequently by @code{assemble_name}, should -produce the output that @code{ASM_OUTPUT_INTERNAL_LABEL} would produce +produce the output that @code{(*targetm.asm_out.internal_label)} would produce with the same @var{prefix} and @var{num}. If the string begins with @samp{*}, then @code{assemble_name} will @@ -6796,6 +6817,9 @@ conflict with the user's own symbols. Most assemblers allow periods or percent signs in assembler symbols; putting at least one of these between the name and the number will suffice. +If this macro is not defined, a default definition will be provided +which is correct for most systems. + @findex ASM_OUTPUT_DEF @item ASM_OUTPUT_DEF (@var{stream}, @var{name}, @var{value}) A C statement to output to the stdio stream @var{stream} assembler code @@ -7365,7 +7389,7 @@ A C statement to output to the stdio stream @var{stream} an assembler pseudo-instruction to generate a difference between two labels. @var{value} and @var{rel} are the numbers of two internal labels. The definitions of these labels are output using -@code{ASM_OUTPUT_INTERNAL_LABEL}, and they must be printed in the same +@code{(*targetm.asm_out.internal_label)}, and they must be printed in the same way here. For example, @example @@ -7387,7 +7411,7 @@ in a dispatch table are absolute. The definition should be a C statement to output to the stdio stream @var{stream} an assembler pseudo-instruction to generate a reference to a label. @var{value} is the number of an internal label whose -definition is output using @code{ASM_OUTPUT_INTERNAL_LABEL}. +definition is output using @code{(*targetm.asm_out.internal_label)}. For example, @example @@ -7398,7 +7422,7 @@ fprintf (@var{stream}, "\t.word L%d\n", @var{value}) @item ASM_OUTPUT_CASE_LABEL (@var{stream}, @var{prefix}, @var{num}, @var{table}) Define this if the label before a jump-table needs to be output specially. The first three arguments are the same as for -@code{ASM_OUTPUT_INTERNAL_LABEL}; the fourth argument is the +@code{(*targetm.asm_out.internal_label)}; the fourth argument is the jump-table which follows (a @code{jump_insn} containing an @code{addr_vec} or @code{addr_diff_vec}). @@ -7406,7 +7430,7 @@ This feature is used on system V to output a @code{swbeg} statement for the table. If this macro is not defined, these labels are output with -@code{ASM_OUTPUT_INTERNAL_LABEL}. +@code{(*targetm.asm_out.internal_label)}. @findex ASM_OUTPUT_CASE_END @item ASM_OUTPUT_CASE_END (@var{stream}, @var{num}, @var{table}) |