assembler: Don't warn if identical declared registers are redefined

There's no real need to warn when the same register is declared twice.
Currently the libva driver does do that and this warning makes other
errors really hide in a sea of warnings.

Redefining a register with different parameters is a real error though,
so we should not allow that and error out in that case.

Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>

1 files changed, 59 insertions, 15 deletions

diff --git a/assembler/gram.y b/assembler/gram.y
index be8ff019..8b56bd9a 100644
--- a/assembler/gram.y
+++ b/assembler/gram.y
@@ -96,6 +96,46 @@ void set_direct_dst_operand(struct brw_reg *dst, struct brw_reg *reg,
 void set_direct_src_operand(struct src_operand *src, struct brw_reg *reg,
 			    int type);
 
+/* like strcmp, but handles NULL pointers */
+static bool strcmp0(const char *s1, const char* s2)
+{
+    if (!s1)
+	return -(s1 != s2);
+    if (!s2)
+	return s1 != s2;
+    return strcmp (s1, s2);
+}
+
+static bool region_equal(struct region *r1, struct region *r2)
+{
+    return memcmp(r1, r2, sizeof(struct region)) == 0;
+}
+
+static bool reg_equal(struct brw_reg *r1, struct brw_reg *r2)
+{
+    return memcmp(r1, r2, sizeof(struct brw_reg)) == 0;
+}
+
+static bool declared_register_equal(struct declared_register *r1,
+				     struct declared_register *r2)
+{
+    if (strcmp0(r1->name, r2->name) != 0)
+	return false;
+
+    if (!reg_equal(&r1->reg, &r2->reg))
+	return false;
+
+    if (!region_equal(&r1->src_region, &r2->src_region))
+	return false;
+
+    if (r1->element_size != r2->element_size ||
+        r1->dst_region != r2->dst_region ||
+	r1->type != r2->type)
+	return false;
+
+    return true;
+}
+
 static void brw_program_init(struct brw_program *p)
 {
    memset(p, 0, sizeof(struct brw_program));
@@ -431,23 +471,27 @@ declare_type:	TYPE EQ regtype
 ;
 declare_pragma:	DECLARE_PRAGMA STRING declare_base declare_elementsize declare_srcregion declare_dstregion declare_type
 		{
-		    struct declared_register *reg;
-		    int defined;
-		    defined = (reg = find_register($2)) != NULL;
-		    if (defined) {
-			fprintf(stderr, "WARNING: %s already defined\n", $2);
+		    struct declared_register reg, *found, *new_reg;
+
+		    reg.name = $2;
+		    reg.reg = $3;
+		    reg.element_size = $4;
+		    reg.src_region = $5;
+		    reg.dst_region = $6;
+		    reg.type = $7;
+
+		    found = find_register($2);
+		    if (found) {
+		        if (!declared_register_equal(&reg, found)) {
+			    fprintf(stderr, "Error: %s already defined and "
+				    "definitions don't agree\n", $2);
+			    YYERROR;
+			}
 			free($2); // $2 has been malloc'ed by strdup
 		    } else {
-			reg = calloc(sizeof(struct declared_register), 1);
-			reg->name = $2;
-		    }
-		    reg->reg = $3;
-		    reg->element_size = $4;
-		    reg->src_region = $5;
-		    reg->dst_region = $6;
-		    reg->type = $7;
-		    if (!defined) {
-			insert_register(reg);
+			new_reg = malloc(sizeof(struct declared_register));
+			*new_reg = reg;
+			insert_register(new_reg);
 		    }
 		}
 ;