glcpp: Implicitly resolve version after the first non-space/hash token.

We resolved the implicit version directive when processing control lines,
such as #ifdef, to ensure any built-in macros exist.  However, we failed
to resolve it when handling ordinary text.

For example,

        int x = __VERSION__;

should resolve __VERSION__ to 110, but since we never resolved the implicit
version, none of the built-in macros exist, so it was left as is.

This also meant we allowed the following shader to slop through:

        123
        #version 120

Nothing would cause the implicit version to take effect, so when we saw
the #version directive, we thought everything was peachy.

This patch makes the lexer's per-token action resolve the implicit
version on the first non-space/newline/hash token that isn't part of
a #version directive, fulfilling the GLSL language spec:

"The #version directive must occur in a shader before anything else,
 except for comments and white space."

Because we emit #version as HASH_TOKEN then VERSION_TOKEN, we have to
allow HASH_TOKEN to slop through as well, so we don't resolve the
implicit version as soon as we see the # character.  However, this is
fine, because the parser's HASH_TOKEN NEWLINE rule does resolve the
version, disallowing cases like:

        #
        #version 120

This patch also adds the above shaders as new glcpp tests.

Fixes dEQP-GLES2.functional.shaders.preprocessor.predefined_macros.
{gl_es_1_vertex,gl_es_1_fragment}.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

src/compiler/glsl/glcpp/glcpp-lex.l

@@ -120,6 +120,11 @@ void glcpp_set_column (int  column_no , yyscan_t yyscanner);
 static int
 glcpp_lex_update_state_per_token (glcpp_parser_t *parser, int token)
 {
+	if (token != NEWLINE && token != SPACE && token != HASH_TOKEN &&
+	    !parser->lexing_version_directive) {
+		glcpp_parser_resolve_implicit_version(parser);
+	}
+
 	/* After the first non-space token in a line, we won't
 	 * allow any '#' to introduce a directive. */
 	if (token == NEWLINE) {
@@ -285,6 +290,7 @@ HEXADECIMAL_INTEGER	0[xX][0-9a-fA-F]+[uU]?
 <HASH>version{HSPACE}+ {
 	BEGIN INITIAL;
 	yyextra->space_tokens = 0;
+	yyextra->lexing_version_directive = 1;
 	RETURN_STRING_TOKEN (VERSION_TOKEN);
 }
 
@@ -536,6 +542,7 @@ HEXADECIMAL_INTEGER	0[xX][0-9a-fA-F]+[uU]?
 	}
 	yyextra->space_tokens = 1;
 	yyextra->lexing_directive = 0;
+	yyextra->lexing_version_directive = 0;
 	yylineno++;
 	yycolumn = 0;
 	RETURN_TOKEN_NEVER_SKIP (NEWLINE);
@@ -546,6 +553,7 @@ HEXADECIMAL_INTEGER	0[xX][0-9a-fA-F]+[uU]?
 		glcpp_error(yylloc, yyextra, "Unterminated comment");
 	BEGIN DONE; /* Don't keep matching this rule forever. */
 	yyextra->lexing_directive = 0;
+	yyextra->lexing_version_directive = 0;
 	if (! parser->last_token_was_newline)
 		RETURN_TOKEN (NEWLINE);
 }

src/compiler/glsl/glcpp/glcpp.h

@@ -176,6 +176,7 @@ struct glcpp_parser {
 	struct hash_table *defines;
 	active_list_t *active;
 	int lexing_directive;
+	int lexing_version_directive;
 	int space_tokens;
 	int last_token_was_newline;
 	int last_token_was_space;

src/compiler/glsl/glcpp/tests/144-implicit-version.c

@@ -0,0 +1 @@
+int x = __VERSION__;

src/compiler/glsl/glcpp/tests/144-implicit-version.c.expected

@@ -0,0 +1 @@
+int x = 110;

src/compiler/glsl/glcpp/tests/145-version-first.c

@@ -0,0 +1,2 @@
+123
+#version 120

src/compiler/glsl/glcpp/tests/145-version-first.c.expected

@@ -0,0 +1,3 @@
+0:2(1): preprocessor error: #version must appear on the first line
+123
+

src/compiler/glsl/glcpp/tests/146-version-first-hash.c

@@ -0,0 +1,2 @@
+#
+#version 120

src/compiler/glsl/glcpp/tests/146-version-first-hash.c.expected

@@ -0,0 +1,3 @@
+0:1(3): preprocessor error: #version must appear on the first line
+
+