1 
2 #include "radeon_compiler.h"
3 #include "radeon_compiler_util.h"
4 #include "radeon_opcodes.h"
5 #include "radeon_program_pair.h"
6 
mark_used_presub(struct rc_pair_sub_instruction * sub)7 static void mark_used_presub(struct rc_pair_sub_instruction * sub)
8 {
9 	if (sub->Src[RC_PAIR_PRESUB_SRC].Used) {
10 		unsigned int presub_reg_count = rc_presubtract_src_reg_count(
11 					sub->Src[RC_PAIR_PRESUB_SRC].Index);
12 		unsigned int i;
13 		for (i = 0; i < presub_reg_count; i++) {
14 			sub->Src[i].Used = 1;
15 		}
16 	}
17 }
18 
mark_used(struct rc_instruction * inst,struct rc_pair_sub_instruction * sub)19 static void mark_used(
20 	struct rc_instruction * inst,
21 	struct rc_pair_sub_instruction * sub)
22 {
23 	unsigned int i;
24 	const struct rc_opcode_info * info = rc_get_opcode_info(sub->Opcode);
25 	for (i = 0; i < info->NumSrcRegs; i++) {
26 		unsigned int src_type = rc_source_type_swz(sub->Arg[i].Swizzle);
27 		if (src_type & RC_SOURCE_RGB) {
28 			inst->U.P.RGB.Src[sub->Arg[i].Source].Used = 1;
29 		}
30 
31 		if (src_type & RC_SOURCE_ALPHA) {
32 			inst->U.P.Alpha.Src[sub->Arg[i].Source].Used = 1;
33 		}
34 	}
35 }
36 
37 /**
38  * This pass finds sources that are not used by their instruction and marks
39  * them as unused.
40  */
rc_pair_remove_dead_sources(struct radeon_compiler * c,void * user)41 void rc_pair_remove_dead_sources(struct radeon_compiler * c, void *user)
42 {
43 	struct rc_instruction * inst;
44 	for (inst = c->Program.Instructions.Next;
45 					inst != &c->Program.Instructions;
46 					inst = inst->Next) {
47 		unsigned int i;
48 		if (inst->Type == RC_INSTRUCTION_NORMAL)
49 			continue;
50 
51 		/* Mark all sources as unused */
52 		for (i = 0; i < 4; i++) {
53 			inst->U.P.RGB.Src[i].Used = 0;
54 			inst->U.P.Alpha.Src[i].Used = 0;
55 		}
56 		mark_used(inst, &inst->U.P.RGB);
57 		mark_used(inst, &inst->U.P.Alpha);
58 
59 		mark_used_presub(&inst->U.P.RGB);
60 		mark_used_presub(&inst->U.P.Alpha);
61 	}
62 }
63