1 /*
2  * Copyright 2011 Tom Stellard <tstellar@gmail.com>
3  *
4  * All Rights Reserved.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining
7  * a copy of this software and associated documentation files (the
8  * "Software"), to deal in the Software without restriction, including
9  * without limitation the rights to use, copy, modify, merge, publish,
10  * distribute, sublicense, and/or sell copies of the Software, and to
11  * permit persons to whom the Software is furnished to do so, subject to
12  * the following conditions:
13  *
14  * The above copyright notice and this permission notice (including the
15  * next paragraph) shall be included in all copies or substantial
16  * portions of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
19  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
21  * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
22  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
23  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
24  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25  *
26  */
27 
28 #include "radeon_compiler.h"
29 #include "radeon_compiler_util.h"
30 #include "radeon_opcodes.h"
31 #include "radeon_program_pair.h"
32 
mark_used_presub(struct rc_pair_sub_instruction * sub)33 static void mark_used_presub(struct rc_pair_sub_instruction * sub)
34 {
35 	if (sub->Src[RC_PAIR_PRESUB_SRC].Used) {
36 		unsigned int presub_reg_count = rc_presubtract_src_reg_count(
37 					sub->Src[RC_PAIR_PRESUB_SRC].Index);
38 		unsigned int i;
39 		for (i = 0; i < presub_reg_count; i++) {
40 			sub->Src[i].Used = 1;
41 		}
42 	}
43 }
44 
mark_used(struct rc_instruction * inst,struct rc_pair_sub_instruction * sub)45 static void mark_used(
46 	struct rc_instruction * inst,
47 	struct rc_pair_sub_instruction * sub)
48 {
49 	unsigned int i;
50 	const struct rc_opcode_info * info = rc_get_opcode_info(sub->Opcode);
51 	for (i = 0; i < info->NumSrcRegs; i++) {
52 		unsigned int src_type = rc_source_type_swz(sub->Arg[i].Swizzle);
53 		if (src_type & RC_SOURCE_RGB) {
54 			inst->U.P.RGB.Src[sub->Arg[i].Source].Used = 1;
55 		}
56 
57 		if (src_type & RC_SOURCE_ALPHA) {
58 			inst->U.P.Alpha.Src[sub->Arg[i].Source].Used = 1;
59 		}
60 	}
61 }
62 
63 /**
64  * This pass finds sources that are not used by their instruction and marks
65  * them as unused.
66  */
rc_pair_remove_dead_sources(struct radeon_compiler * c,void * user)67 void rc_pair_remove_dead_sources(struct radeon_compiler * c, void *user)
68 {
69 	struct rc_instruction * inst;
70 	for (inst = c->Program.Instructions.Next;
71 					inst != &c->Program.Instructions;
72 					inst = inst->Next) {
73 		unsigned int i;
74 		if (inst->Type == RC_INSTRUCTION_NORMAL)
75 			continue;
76 
77 		/* Mark all sources as unused */
78 		for (i = 0; i < 4; i++) {
79 			inst->U.P.RGB.Src[i].Used = 0;
80 			inst->U.P.Alpha.Src[i].Used = 0;
81 		}
82 		mark_used(inst, &inst->U.P.RGB);
83 		mark_used(inst, &inst->U.P.Alpha);
84 
85 		mark_used_presub(&inst->U.P.RGB);
86 		mark_used_presub(&inst->U.P.Alpha);
87 	}
88 }
89