ARB prog parser: Add support for GL_ARB_fragment_program_shadow

Passes the piglit asmparsertest shadow-0[123].txt tests and
progs/demos/shadowtex.

src/mesa/shader/program_lexer.l

@@ -29,6 +29,7 @@
 
 #define require_ARB_vp (yyextra->mode == ARB_vertex)
 #define require_ARB_fp (yyextra->mode == ARB_fragment)
+#define require_shadow (yyextra->option.Shadow)
 #define require_rect   (yyextra->option.TexRect)
 
 #define return_token_or_IDENTIFIER(condition, token)	\
@@ -295,6 +296,9 @@ texture                   { return_token_or_IDENTIFIER(require_ARB_fp, TEXTURE_U
 3D                        { return_token_or_IDENTIFIER(require_ARB_fp, TEX_3D); }
 CUBE                      { return_token_or_IDENTIFIER(require_ARB_fp, TEX_CUBE); }
 RECT                      { return_token_or_IDENTIFIER(require_ARB_fp && require_rect, TEX_RECT); }
+SHADOW1D                  { return_token_or_IDENTIFIER(require_ARB_fp && require_shadow, TEX_SHADOW1D); }
+SHADOW2D                  { return_token_or_IDENTIFIER(require_ARB_fp && require_shadow, TEX_SHADOW2D); }
+SHADOWRECT                { return_token_or_IDENTIFIER(require_ARB_fp && require_shadow && require_rect, TEX_SHADOWRECT); }
 
 [_a-zA-Z$][_a-zA-Z0-9$]*  {
    yylval->string = strdup(yytext);

src/mesa/shader/program_parse.tab.h

@@ -124,17 +124,20 @@
      TEX_3D = 340,
      TEX_CUBE = 341,
      TEX_RECT = 342,
-     VERTEX = 343,
-     VTXATTRIB = 344,
-     WEIGHT = 345,
-     IDENTIFIER = 346,
-     MASK4 = 347,
-     MASK3 = 348,
-     MASK2 = 349,
-     MASK1 = 350,
-     SWIZZLE = 351,
-     DOT_DOT = 352,
-     DOT = 353
+     TEX_SHADOW1D = 343,
+     TEX_SHADOW2D = 344,
+     TEX_SHADOWRECT = 345,
+     VERTEX = 346,
+     VTXATTRIB = 347,
+     WEIGHT = 348,
+     IDENTIFIER = 349,
+     MASK4 = 350,
+     MASK3 = 351,
+     MASK2 = 352,
+     MASK1 = 353,
+     SWIZZLE = 354,
+     DOT_DOT = 355,
+     DOT = 356
    };
 #endif
 
@@ -167,7 +170,7 @@ typedef union YYSTYPE
 
 
 /* Line 1676 of yacc.c  */
-#line 171 "program_parse.tab.h"
+#line 174 "program_parse.tab.h"
 } YYSTYPE;
 # define YYSTYPE_IS_TRIVIAL 1
 # define yystype YYSTYPE /* obsolescent; will be withdrawn */

src/mesa/shader/program_parse.y

@@ -157,6 +157,7 @@ static struct asm_instruction *asm_instruction_ctor(gl_inst_opcode op,
 %token SCENECOLOR SECONDARY SHININESS SIZE SPECULAR SPOT STATE
 %token TEXCOORD TEXENV TEXGEN TEXGEN_Q TEXGEN_R TEXGEN_S TEXGEN_T TEXTURE TRANSPOSE
 %token TEXTURE_UNIT TEX_1D TEX_2D TEX_3D TEX_CUBE TEX_RECT
+%token TEX_SHADOW1D TEX_SHADOW2D TEX_SHADOWRECT
 %token VERTEX VTXATTRIB
 %token WEIGHT
 
@@ -383,11 +384,43 @@ SAMPLE_instruction: SAMPLE_OP maskedDstReg ',' swizzleSrcReg ',' texImageUnit ',
 	{
 	   $$ = asm_instruction_ctor($1.Opcode, & $2, & $4, NULL, NULL);
 	   if ($$ != NULL) {
+	      const GLbitfield tex_mask = (1U << $6);
+	      GLbitfield shadow_tex = 0;
+	      GLbitfield target_mask = 0;
+
+
 	      $$->Base.SaturateMode = $1.SaturateMode;
 	      $$->Base.TexSrcUnit = $6;
-	      $$->Base.TexSrcTarget = $8;
 
-	      state->prog->TexturesUsed[$6] |= (1U << $8);
+	      if ($8 < 0) {
+		 shadow_tex = tex_mask;
+
+		 $$->Base.TexSrcTarget = -$8;
+		 $$->Base.TexShadow = 1;
+	      } else {
+		 $$->Base.TexSrcTarget = $8;
+	      }
+
+	      target_mask = (1U << $$->Base.TexSrcTarget);
+
+	      /* If this texture unit was previously accessed and that access
+	       * had a different texture target, generate an error.
+	       *
+	       * If this texture unit was previously accessed and that access
+	       * had a different shadow mode, generate an error.
+	       */
+	      if ((state->prog->TexturesUsed[$6] != 0)
+		  && ((state->prog->TexturesUsed[$6] != target_mask)
+		      || ((state->prog->ShadowSamplers & tex_mask)
+			  != shadow_tex))) {
+		 yyerror(& @8, state,
+			 "multiple targets used on one texture image unit");
+		 YYERROR;
+	      }
+
+
+	      state->prog->TexturesUsed[$6] |= target_mask;
+	      state->prog->ShadowSamplers |= shadow_tex;
 	   }
 	}
 	;
@@ -410,6 +443,9 @@ texTarget: TEX_1D  { $$ = TEXTURE_1D_INDEX; }
 	| TEX_3D   { $$ = TEXTURE_3D_INDEX; }
 	| TEX_CUBE { $$ = TEXTURE_CUBE_INDEX; }
 	| TEX_RECT { $$ = TEXTURE_RECT_INDEX; }
+	| TEX_SHADOW1D   { $$ = -TEXTURE_1D_INDEX; }
+	| TEX_SHADOW2D   { $$ = -TEXTURE_2D_INDEX; }
+	| TEX_SHADOWRECT { $$ = -TEXTURE_RECT_INDEX; }
 	;
 
 SWZ_instruction: SWZ maskedDstReg ',' srcReg ',' extendedSwizzle