On Mon, May 30, 2016 at 5:15 PM, Prasad Ghangal
<prasad.ghan...@gmail.com> wrote:
> Hi,
>
> As David suggested in his rtlfe patch,
> this patch recognizes __GIMPLE keyword and switches to
> c_parser_parse_gimple_body by providing -fgimple option.
>
>
> diff --git a/gcc/c-family/c-common.c b/gcc/c-family/c-common.c
> index 4568cf6..41a8f05 100644
> --- a/gcc/c-family/c-common.c
> +++ b/gcc/c-family/c-common.c
> @@ -511,6 +511,7 @@ const struct c_common_resword c_common_reswords[] =
> { "__underlying_type", RID_UNDERLYING_TYPE, D_CXXONLY },
> { "__volatile", RID_VOLATILE, 0 },
> { "__volatile__", RID_VOLATILE, 0 },
> + { "__GIMPLE", RID_GIMPLE, 0 },
I think we need a D_GIMPLE_ONLY flag which disables this reserved word
when -fgimple is not
in effect. That's something to put on a list of TODOs once everything
else works fine (it's not
high priority but a requirement to merge to trunk). For now you can
at least put D_CONLY there
(as -fgimple is a C only flag).
> { "alignas", RID_ALIGNAS, D_CXXONLY | D_CXX11 | D_CXXWARN },
> { "alignof", RID_ALIGNOF, D_CXXONLY | D_CXX11 | D_CXXWARN },
> { "asm", RID_ASM, D_ASM },
> diff --git a/gcc/c-family/c-common.h b/gcc/c-family/c-common.h
> index 0295532..23a401d 100644
> --- a/gcc/c-family/c-common.h
> +++ b/gcc/c-family/c-common.h
> @@ -104,6 +104,9 @@ enum rid
> RID_DFLOAT32, RID_DFLOAT64, RID_DFLOAT128,
> RID_FRACT, RID_ACCUM, RID_AUTO_TYPE, RID_BUILTIN_CALL_WITH_STATIC_CHAIN,
>
> + /* "__GIMPLE", for the GIMPLE-parsing extension to the C frontend. */
> + RID_GIMPLE,
> +
> /* C11 */
> RID_ALIGNAS, RID_GENERIC,
>
> diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
> index 918df16..8ab56af 100644
> --- a/gcc/c-family/c.opt
> +++ b/gcc/c-family/c.opt
> @@ -200,6 +200,10 @@ F
> Driver C ObjC C++ ObjC++ Joined Separate MissingArgError(missing path
> after %qs)
> -F <dir> Add <dir> to the end of the main framework include path.
>
> +fgimple
> +C Var(flag_gimple) Init(0)
> +Enable parsing GIMPLE
> +
> H
> C ObjC C++ ObjC++
> Print the name of header files as they are used.
> diff --git a/gcc/c/c-parser.c b/gcc/c/c-parser.c
> index 1cf4fb4..c5a4d3f 100644
> --- a/gcc/c/c-parser.c
> +++ b/gcc/c/c-parser.c
> @@ -1396,6 +1396,7 @@ static bool c_parser_cilk_verify_simd (c_parser
> *, enum pragma_context);
> static tree c_parser_array_notation (location_t, c_parser *, tree, tree);
> static tree c_parser_cilk_clause_vectorlength (c_parser *, tree, bool);
> static void c_parser_cilk_grainsize (c_parser *, bool *);
> +static void c_parser_parse_gimple_body (c_parser *parser);
>
> /* Parse a translation unit (C90 6.7, C99 6.9).
>
> @@ -1638,6 +1639,7 @@ c_parser_declaration_or_fndef (c_parser *parser,
> bool fndef_ok,
> tree all_prefix_attrs;
> bool diagnosed_no_specs = false;
> location_t here = c_parser_peek_token (parser)->location;
> + bool gimple_body_p = false;
>
> if (static_assert_ok
> && c_parser_next_token_is_keyword (parser, RID_STATIC_ASSERT))
> @@ -1687,6 +1689,17 @@ c_parser_declaration_or_fndef (c_parser
> *parser, bool fndef_ok,
> c_parser_skip_to_end_of_block_or_statement (parser);
> return;
> }
> +
> + if (c_parser_next_token_is (parser, CPP_KEYWORD))
> + {
> + c_token *kw_token = c_parser_peek_token (parser);
> + if (kw_token->keyword == RID_GIMPLE)
> + {
> + gimple_body_p = true;
> + c_parser_consume_token (parser);
> + }
> + }
> +
> finish_declspecs (specs);
> bool auto_type_p = specs->typespec_word == cts_auto_type;
> if (c_parser_next_token_is (parser, CPP_SEMICOLON))
> @@ -2102,6 +2115,14 @@ c_parser_declaration_or_fndef (c_parser
> *parser, bool fndef_ok,
> oacc_routine_clauses, false, first, true);
> DECL_STRUCT_FUNCTION (current_function_decl)->function_start_locus
> = c_parser_peek_token (parser)->location;
> +
> + if (gimple_body_p && flag_gimple)
> + {
> + c_parser_parse_gimple_body (parser);
> + finish_function ();
> + return;
> + }
> +
> fnbody = c_parser_compound_statement (parser);
> if (flag_cilkplus && contains_array_notation_expr (fnbody))
> fnbody = expand_array_notation_exprs (fnbody);
> @@ -2123,7 +2144,7 @@ c_parser_declaration_or_fndef (c_parser *parser,
> bool fndef_ok,
> add_stmt (fnbody);
> finish_function ();
> }
> -
> +
> timevar_pop (tv);
> break;
> }
Always avoid stay changes like this.
> @@ -18055,4 +18076,23 @@ c_parser_array_notation (location_t loc,
> c_parser *parser, tree initial_index,
> return value_tree;
> }
>
> +/* Parse the body of a function declaration marked with "__GIMPLE". */
> +
> +void
> +c_parser_parse_gimple_body (c_parser *parser)
> +{
> + if (!c_parser_require (parser, CPP_OPEN_BRACE, "expected %<{%>"))
> + return;
> +
> + location_t loc1 = c_parser_peek_token (parser)->location;
> + inform (loc1, "start of GIMPLE");
> +
> + while (c_parser_next_token_is_not (parser, CPP_CLOSE_BRACE))
> + {
> + c_parser_consume_token (parser);
> + }
> +
> + c_parser_consume_token (parser);
> +}
> +
> #include "gt-c-c-parser.h"
>
>
>
>
> GIMPLE function body consists of GIMPLE statements. For parsing GIMPLE
> function body, we need to populate gimple body with gimple statements
> which will emit GIMPLE as it is.
>
> I would like to hear suggestions about how can I emit GIMPLE directly from FE.
You should be able to use gimple_build_* functions declared in gimple.h, for
example
stmt = gimple_build_assign (res, PLUS_EXPR, op0, op1);
will build an assignment to res computing op0 + op1. res, op0 and op1 can be
most easily parsed using the appropriate C parsing functions for identifiers.
You'll need to queue stmts you built in a gimple_seq and attach that to the
function via gimple_set_body (fndecl, sequence).
I suggest you try with a "simple" example like
int a;
__GIMPLE void foo (void)
{
a = 1;
}
going forward with handling a = 1 + 2; and then, sth you'll need very quickly,
handle local declarations like
int a;
__GIMPLE int foo (void)
{
int b;
b = a;
b = b + 1;
a = b;
}
this is sth C code like int foo (void) { a = a + 1; } is gimplified to.
Richard.
>
>
> Thanks,
> Prasad Ghangal
