[Mesa-stable] [Mesa-dev] [PATCH] glsl: fixer lexer for unreachable defines

[Dylan Baker]

Quoting Timothy Arceri (2018-09-05 19:40:34)
> Cc: mesa-stable at lists.freedesktop.org
> 
> On 01/09/18 23:57, Timothy Arceri wrote:
> > If we have something like:
> > 
> >     #ifdef NOT_DEFINED
> >     #define A_MACRO(x) \
> >       if (x)
> >     #endif
> > 
> > The # on the #define is not skipped but the define itself is so
> > this then gets recognised as #if.
> > 
> > Until 28a3731e3f this didn't happen because we ended up in
> > <HASH>{NONSPACE} where BEGIN INITIAL was called stopping the
> > problem from happening.
> > 
> > This change makes sure we never call RETURN_TOKEN_NEVER_SKIP for
> > if/else/endif when processing a define.
> > 
> > Cc: Ian Romanick <idr at freedesktop.org>
> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107772
> > ---
> >   src/compiler/glsl/glcpp/glcpp-lex.l | 60 ++++++++++++++++++-----------
> >   src/compiler/glsl/glcpp/glcpp.h     |  1 +
> >   2 files changed, 38 insertions(+), 23 deletions(-)
> > 
> > diff --git a/src/compiler/glsl/glcpp/glcpp-lex.l b/src/compiler/glsl/glcpp/glcpp-lex.l
> > index fe5845acd4e..f7003da0cc8 100644
> > --- a/src/compiler/glsl/glcpp/glcpp-lex.l
> > +++ b/src/compiler/glsl/glcpp/glcpp-lex.l
> > @@ -289,6 +289,7 @@ HEXADECIMAL_INTEGER       0[xX][0-9a-fA-F]+[uU]?
> >            * token. */
> >       if (parser->first_non_space_token_this_line) {
> >               BEGIN HASH;
> > +             yyextra->in_define = false;
> >       }
> >   
> >       RETURN_TOKEN_NEVER_SKIP (HASH_TOKEN);
> > @@ -336,43 +337,55 @@ HEXADECIMAL_INTEGER     0[xX][0-9a-fA-F]+[uU]?
> >       /* For the pre-processor directives, we return these tokens
> >        * even when we are otherwise skipping. */
> >   <HASH>ifdef {
> > -     BEGIN INITIAL;
> > -     yyextra->lexing_directive = 1;
> > -     yyextra->space_tokens = 0;
> > -     RETURN_TOKEN_NEVER_SKIP (IFDEF);
> > +     if (!yyextra->in_define) {
> > +             BEGIN INITIAL;
> > +             yyextra->lexing_directive = 1;
> > +             yyextra->space_tokens = 0;
> > +             RETURN_TOKEN_NEVER_SKIP (IFDEF);
> > +     }
> >   }
> >   
> >   <HASH>ifndef {
> > -     BEGIN INITIAL;
> > -     yyextra->lexing_directive = 1;
> > -     yyextra->space_tokens = 0;
> > -     RETURN_TOKEN_NEVER_SKIP (IFNDEF);
> > +     if (!yyextra->in_define) {
> > +             BEGIN INITIAL;
> > +             yyextra->lexing_directive = 1;
> > +             yyextra->space_tokens = 0;
> > +             RETURN_TOKEN_NEVER_SKIP (IFNDEF);
> > +     }
> >   }
> >   
> >   <HASH>if/[^_a-zA-Z0-9] {
> > -     BEGIN INITIAL;
> > -     yyextra->lexing_directive = 1;
> > -     yyextra->space_tokens = 0;
> > -     RETURN_TOKEN_NEVER_SKIP (IF);
> > +     if (!yyextra->in_define) {
> > +             BEGIN INITIAL;
> > +             yyextra->lexing_directive = 1;
> > +             yyextra->space_tokens = 0;
> > +             RETURN_TOKEN_NEVER_SKIP (IF);
> > +     }
> >   }
> >   
> >   <HASH>elif/[^_a-zA-Z0-9] {
> > -     BEGIN INITIAL;
> > -     yyextra->lexing_directive = 1;
> > -     yyextra->space_tokens = 0;
> > -     RETURN_TOKEN_NEVER_SKIP (ELIF);
> > +     if (!yyextra->in_define) {
> > +             BEGIN INITIAL;
> > +             yyextra->lexing_directive = 1;
> > +             yyextra->space_tokens = 0;
> > +             RETURN_TOKEN_NEVER_SKIP (ELIF);
> > +     }
> >   }
> >   
> >   <HASH>else {
> > -     BEGIN INITIAL;
> > -     yyextra->space_tokens = 0;
> > -     RETURN_TOKEN_NEVER_SKIP (ELSE);
> > +     if (!yyextra->in_define) {
> > +             BEGIN INITIAL;
> > +             yyextra->space_tokens = 0;
> > +             RETURN_TOKEN_NEVER_SKIP (ELSE);
> > +     }
> >   }
> >   
> >   <HASH>endif {
> > -     BEGIN INITIAL;
> > -     yyextra->space_tokens = 0;
> > -     RETURN_TOKEN_NEVER_SKIP (ENDIF);
> > +     if (!yyextra->in_define) {
> > +             BEGIN INITIAL;
> > +             yyextra->space_tokens = 0;
> > +             RETURN_TOKEN_NEVER_SKIP (ENDIF);
> > +     }
> >   }
> >   
> >   <HASH>error[^\r\n]* {
> > @@ -399,7 +412,8 @@ HEXADECIMAL_INTEGER       0[xX][0-9a-fA-F]+[uU]?
> >        *        and not whitespace). This will generate an error.
> >        */
> >   <HASH>define{HSPACE}* {
> > -     if (! parser->skipping) {
> > +     yyextra->in_define = true;
> > +     if (!parser->skipping) {
> >               BEGIN DEFINE;
> >               yyextra->space_tokens = 0;
> >               RETURN_TOKEN (DEFINE_TOKEN);
> > diff --git a/src/compiler/glsl/glcpp/glcpp.h b/src/compiler/glsl/glcpp/glcpp.h
> > index c7e382ed30c..e786b24b132 100644
> > --- a/src/compiler/glsl/glcpp/glcpp.h
> > +++ b/src/compiler/glsl/glcpp/glcpp.h
> > @@ -197,6 +197,7 @@ struct glcpp_parser {
> >       int first_non_space_token_this_line;
> >       int newline_as_space;
> >       int in_control_line;
> > +     bool in_define;
> >       int paren_count;
> >       int commented_newlines;
> >       skip_node_t *skip_stack;
> > 
> _______________________________________________
> mesa-stable mailing list
> mesa-stable at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/mesa-stable

Staged for 18.1. CCing Andres.

Dylan
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