Add support for labeled and conditional branches

Signed-off-by: Keith Packard <keithp@keithp.com>

assembler/src/brw_structs.h

@@ -1336,6 +1336,7 @@ struct brw_instruction
       GLint id;
       GLfloat fd;
    } bits3;
+   char *reloc_target;
 };
 
 

assembler/src/gen4asm.h

@@ -106,11 +106,14 @@ typedef struct {
 
 /**
  * This structure is just the list container for instructions accumulated by
- * the parser.
+ * the parser and labels.
  */
 struct brw_program_instruction {
 	struct brw_instruction instruction;
 	struct brw_program_instruction *next;
+	GLuint islabel;
+	GLuint inst_offset;
+	char   *string;
 };
 
 /**

assembler/src/gram.y

@@ -54,7 +54,7 @@ void set_direct_src_operand(struct src_operand *src, struct direct_reg *reg,
 %start ROOT
 
 %union {
-	char *s;
+	char *string;
 	int integer;
 	double number;
 	struct brw_instruction instruction;
@@ -71,6 +71,7 @@ void set_direct_src_operand(struct src_operand *src, struct direct_reg *reg,
 	struct src_operand src_operand;
 }
 
+%token COLON
 %token SEMICOLON
 %token LPAREN RPAREN
 %token LANGLE RANGLE
@@ -108,6 +109,7 @@ void set_direct_src_operand(struct src_operand *src, struct direct_reg *reg,
 %token SATURATE
 
 %token <integer> INTEGER
+%token <string> STRING
 %token <number> NUMBER
 
 %token <integer> INV LOG EXP SQRT RSQ POW SIN COS SINCOS INTDIV INTMOD
@@ -122,6 +124,7 @@ void set_direct_src_operand(struct src_operand *src, struct direct_reg *reg,
 %type <instruction> breakinstruction syncinstruction specialinstruction
 %type <instruction> msgtarget
 %type <instruction> instoptions instoption_list predicate
+%type <string> label
 %type <program> instrseq
 %type <integer> instoption
 %type <integer> unaryop binaryop binaryaccop branchloopop breakop
@@ -155,6 +158,13 @@ ROOT:		instrseq
 		}
 ;
 
+
+label:          STRING COLON
+		{
+    		  $$ = $1;
+		}
+;
+
 instrseq:	instruction SEMICOLON instrseq
 		{
 		  struct brw_program_instruction *list_entry =
@@ -176,6 +186,16 @@ instrseq:	instruction SEMICOLON instrseq
 
 		  $$.first = list_entry;
 		}
+                | label instrseq
+                {
+                  struct brw_program_instruction *list_entry =
+                    calloc(sizeof(struct brw_program_instruction), 1);
+                  list_entry->string = $1;
+                  list_entry->islabel = 1;
+                  list_entry->next = $2.first;
+                      $2.first = list_entry;
+                      $$ = $2;
+                }
 		| error SEMICOLON instrseq
 		{
 		  $$ = $3;
@@ -296,10 +316,7 @@ sendinstruction: predicate SEND execsize INTEGER post_dst payload msgtarget
 		}
 ;
 
-/* XXX: This should probably allow predication (i.e. be a branchloopop),
- * though the BNF didn't specify it.
- */
-jumpinstruction: JMPI relativelocation2
+jumpinstruction: predicate JMPI relativelocation2
 		{
 		  struct direct_reg dst;
 		  struct dst_operand ip_dst;
@@ -315,12 +332,43 @@ jumpinstruction: JMPI relativelocation2
 		  dst.subreg_nr = 0;
 
 		  bzero(&$$, sizeof($$));
-		  $$.header.opcode = $1;
+		  $$.header.opcode = $2;
 		  set_direct_dst_operand(&ip_dst, &dst, BRW_REGISTER_TYPE_UD);
+		  set_instruction_predicate(&$$, &$1);
 		  set_instruction_dest(&$$, &ip_dst);
 		  set_direct_src_operand(&ip_src, &dst, BRW_REGISTER_TYPE_UD);
 		  set_instruction_src0(&$$, &ip_src);
-		  set_instruction_src1(&$$, &$2);
+		  set_instruction_src1(&$$, &$3);
+		}
+		| predicate JMPI STRING
+		{
+		    struct direct_reg dst;
+		    struct dst_operand ip_dst;
+		    struct src_operand ip_src;
+		    struct src_operand imm;
+		    
+		    /* The jump instruction requires that the IP register
+	 	     * be the destination and first source operand, while the
+	             * offset is the second source operand.  The next instruction
+		      is the post-incremented IP plus the offset.
+		     */
+		    dst.reg_file = BRW_ARCHITECTURE_REGISTER_FILE;
+		    dst.reg_nr = BRW_ARF_IP;
+		    dst.subreg_nr = 0;
+		    memset (&imm, '\0', sizeof (imm));
+		    imm.reg_file = BRW_IMMEDIATE_VALUE;
+		    imm.reg_type = BRW_REGISTER_TYPE_D;
+		    imm.imm32 = 0;
+		    
+		    bzero(&$$, sizeof($$));
+		    $$.header.opcode = $2;
+		    set_direct_dst_operand(&ip_dst, &dst, BRW_REGISTER_TYPE_UD);
+		    set_instruction_dest(&$$, &ip_dst);
+		    set_instruction_predicate(&$$, &$1);
+		    set_direct_src_operand(&ip_src, &dst, BRW_REGISTER_TYPE_UD);
+		    set_instruction_src0(&$$, &ip_src);
+		    set_instruction_src1(&$$, &imm);
+		    $$.reloc_target = $3;
 		}
 ;
 

assembler/src/lex.l

@@ -5,6 +5,7 @@
 #include "gram.h"
 #include "brw_defines.h"
 
+#include "string.h"
 int saved_state = 0;
 extern char *input_filename;
 
@@ -112,6 +113,7 @@ extern char *input_filename;
 "transpose" { return TRANSPOSE; }
 "interleave" { return INTERLEAVE; }
 
+":" { return COLON; }
 ";" { return SEMICOLON; }
 "(" { return LPAREN; }
 ")" { return RPAREN; }
@@ -171,7 +173,7 @@ extern char *input_filename;
   * rather than the reg number, to avoid a shift/reduce conflict in the
   * predicate control.
   */
-"f0.[0-9]+" {
+"f0."[0-9]+ {
 	yylval.integer = atoi(yytext + 3);
 	return FLAGREG;
 }
@@ -326,6 +328,11 @@ extern char *input_filename;
 	return W;
 }
 
+[a-zA-Z_][0-9a-zA-Z_]* {
+           yylval.string = strdup(yytext);
+           return STRING;
+}
+
 0x[0-9a-fA-F][0-9a-fA-F]* {
 	yylval.integer = strtoul(yytext + 2, NULL, 16);
 	return INTEGER;

assembler/src/main.c

@@ -55,8 +55,8 @@ int main(int argc, char **argv)
 {
 	char *output_file = NULL;
 	FILE *output = stdout;
-	struct brw_program_instruction *entry;
-	int err;
+	struct brw_program_instruction *entry, *entry1;
+	int err, inst_offset;
 	char o;
 
 	while ((o = getopt_long(argc, argv, "o:", longopts, NULL)) != -1) {
@@ -98,22 +98,54 @@ int main(int argc, char **argv)
 			exit(1);
 		}
 	}
+	inst_offset = 0 ;
 	for (entry = compiled_program.first;
-	     entry != NULL;
-	     entry = entry->next) {
+		entry != NULL; entry = entry->next) {
+	    entry->inst_offset = inst_offset;
+	    if (!entry->islabel)
+		inst_offset++;
+	}
+
+	for (entry = compiled_program.first;
+		entry != NULL; entry = entry->next) {
+	    if (!entry->islabel) {
+		if (entry->instruction.reloc_target) {
+		    for (entry1 = entry;
+			    entry1 != NULL; entry1 = entry1->next) {
+			if (entry1->islabel && 
+				strcmp(entry1->string, 
+				    entry->instruction.reloc_target) == 0) {
+			    int offset = 
+				entry1->inst_offset - entry->inst_offset;
+			    entry->instruction.bits3.ud = offset - 1;
+			    break;
+			}
+		    }
+		    if (entry1 == NULL)
+			fprintf(stderr, "can not find lable %s\n",
+				entry->instruction.reloc_target);
+		}
+	    }
+	}
+
+
+	for (entry = compiled_program.first;
+		entry != NULL;
+		entry = entry->next) {
+	    if (!entry->islabel)
 		fprintf(output, "   { 0x%08x, 0x%08x, 0x%08x, 0x%08x },\n",
-		       ((int *)(&entry->instruction))[0],
-		       ((int *)(&entry->instruction))[1],
-		       ((int *)(&entry->instruction))[2],
-		       ((int *)(&entry->instruction))[3]);
+			((int *)(&entry->instruction))[0],
+			((int *)(&entry->instruction))[1],
+			((int *)(&entry->instruction))[2],
+			((int *)(&entry->instruction))[3]);
 	}
 
 	fflush (output);
 	if (ferror (output)) {
-		perror ("Could not flush output file");
-		if (output_file)
-			unlink (output_file);
-		err = 1;
+	    perror ("Could not flush output file");
+	    if (output_file)
+		unlink (output_file);
+	    err = 1;
 	}
 	return err;
 }