/*
* Copyright 2011 Tom Stellard <tstellar@gmail.com>
*
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial
* portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
#include "radeon_variable.h"
#include "memory_pool.h"
#include "radeon_compiler_util.h"
#include "radeon_dataflow.h"
#include "radeon_list.h"
#include "radeon_opcodes.h"
#include "radeon_program.h"
/**
* Rewrite the index and writemask for the destination register of var
* and its friends to new_index and new_writemask. This function also takes
* care of rewriting the swizzles for the sources of var.
*/
void rc_variable_change_dst(
struct rc_variable * var,
unsigned int new_index,
unsigned int new_writemask)
{
struct rc_variable * var_ptr;
struct rc_list * readers;
unsigned int old_mask = rc_variable_writemask_sum(var);
unsigned int conversion_swizzle =
rc_make_conversion_swizzle(old_mask, new_writemask);
for (var_ptr = var; var_ptr; var_ptr = var_ptr->Friend) {
if (var_ptr->Inst->Type == RC_INSTRUCTION_NORMAL) {
rc_normal_rewrite_writemask(var_ptr->Inst,
conversion_swizzle);
var_ptr->Inst->U.I.DstReg.Index = new_index;
} else {
struct rc_pair_sub_instruction * sub;
if (var_ptr->Dst.WriteMask == RC_MASK_W) {
assert(new_writemask
& RC_MASK_W
); sub = &var_ptr->Inst->U.P.Alpha;
} else {
sub = &var_ptr->Inst->U.P.RGB;
rc_pair_rewrite_writemask(sub,
conversion_swizzle);
}
sub->DestIndex = new_index;
}
}
readers = rc_variable_readers_union(var);
for ( ; readers; readers = readers->Next) {
struct rc_reader * reader = readers->Item;
if (reader->Inst->Type == RC_INSTRUCTION_NORMAL) {
reader->U.I.Src->Index = new_index;
reader->U.I.Src->Swizzle = rc_rewrite_swizzle(
reader->U.I.Src->Swizzle, conversion_swizzle);
} else {
struct rc_pair_instruction * pair_inst =
&reader->Inst->U.P;
unsigned int src_type = rc_source_type_swz(
reader->U.P.Arg->Swizzle);
int src_index = reader->U.P.Arg->Source;
if (src_index == RC_PAIR_PRESUB_SRC) {
src_index = rc_pair_get_src_index(
pair_inst, reader->U.P.Src);
}
/* Try to delete the old src, it is OK if this fails,
* because rc_pair_alloc_source might be able to
* find a source the ca be reused.
*/
if (rc_pair_remove_src(reader->Inst, src_type,
src_index, old_mask)) {
/* Reuse the source index of the source that
* was just deleted and set its register
* index. We can't use rc_pair_alloc_source
* for this becuase it might return a source
* index that is already being used. */
if (src_type & RC_SOURCE_RGB) {
pair_inst->RGB.Src[src_index]
.Used = 1;
pair_inst->RGB.Src[src_index]
.Index = new_index;
pair_inst->RGB.Src[src_index]
.File = RC_FILE_TEMPORARY;
}
if (src_type & RC_SOURCE_ALPHA) {
pair_inst->Alpha.Src[src_index]
.Used = 1;
pair_inst->Alpha.Src[src_index]
.Index = new_index;
pair_inst->Alpha.Src[src_index]
.File = RC_FILE_TEMPORARY;
}
} else {
src_index = rc_pair_alloc_source(
&reader->Inst->U.P,
src_type & RC_SOURCE_RGB,
src_type & RC_SOURCE_ALPHA,
RC_FILE_TEMPORARY,
new_index);
if (src_index < 0) {
rc_error(var->C, "Rewrite of inst %u failed "
"Can't allocate source for "
"Inst %u src_type=%x "
"new_index=%u new_mask=%u\n",
var->Inst->IP, reader->Inst->IP, src_type, new_index, new_writemask);
continue;
}
}
reader->U.P.Arg->Swizzle = rc_rewrite_swizzle(
reader->U.P.Arg->Swizzle, conversion_swizzle);
if (reader->U.P.Arg->Source != RC_PAIR_PRESUB_SRC) {
reader->U.P.Arg->Source = src_index;
}
}
}
}
/**
* Compute the live intervals for var and its friends.
*/
void rc_variable_compute_live_intervals(struct rc_variable * var)
{
while(var) {
unsigned int i;
unsigned int start = var->Inst->IP;
for (i = 0; i < var->ReaderCount; i++) {
unsigned int chan;
unsigned int chan_start = start;
unsigned int chan_end = var->Readers[i].Inst->IP;
unsigned int mask = var->Readers[i].WriteMask;
struct rc_instruction * inst;
/* Extend the live interval of T0 to the start of the
* loop for sequences like:
* BGNLOOP
* read T0
* ...
* write T0
* ENDLOOP
*/
if (var->Readers[i].Inst->IP < start) {
struct rc_instruction * bgnloop =
rc_match_endloop(var->Readers[i].Inst);
chan_start = bgnloop->IP;
}
/* Extend the live interval of T0 to the start of the
* loop in case there is a BRK instruction in the loop
* (we don't actually check for a BRK instruction we
* assume there is one somewhere in the loop, which
* there usually is) for sequences like:
* BGNLOOP
* ...
* conditional BRK
* ...
* write T0
* ENDLOOP
* read T0
***************************************************
* Extend the live interval of T0 to the end of the
* loop for sequences like:
* write T0
* BGNLOOP
* ...
* read T0
* ENDLOOP
*/
for (inst = var->Inst; inst != var->Readers[i].Inst;
inst = inst->Next) {
rc_opcode op = rc_get_flow_control_inst(inst);
if (op == RC_OPCODE_ENDLOOP) {
struct rc_instruction * bgnloop =
rc_match_endloop(inst);
if (bgnloop->IP < chan_start) {
chan_start = bgnloop->IP;
}
} else if (op == RC_OPCODE_BGNLOOP) {
struct rc_instruction * endloop =
rc_match_bgnloop(inst);
if (endloop->IP > chan_end) {
chan_end = endloop->IP;
}
}
}
for (chan = 0; chan < 4; chan++) {
if ((mask >> chan) & 0x1) {
if (!var->Live[chan].Used
|| chan_start < var->Live[chan].Start) {
var->Live[chan].Start =
chan_start;
}
if (!var->Live[chan].Used
|| chan_end > var->Live[chan].End) {
var->Live[chan].End = chan_end;
}
var->Live[chan].Used = 1;
}
}
}
var = var->Friend;
}
}
/**
* @return 1 if a and b share a reader
* @return 0 if they do not
*/
static unsigned int readers_intersect(
struct rc_variable * a,
struct rc_variable * b)
{
unsigned int a_index, b_index;
for (a_index = 0; a_index < a->ReaderCount; a_index++) {
struct rc_reader reader_a = a->Readers[a_index];
for (b_index = 0; b_index < b->ReaderCount; b_index++) {
struct rc_reader reader_b = b->Readers[b_index];
if (reader_a.Inst->Type == RC_INSTRUCTION_NORMAL
&& reader_b.Inst->Type == RC_INSTRUCTION_NORMAL
&& reader_a.U.I.Src == reader_b.U.I.Src) {
return 1;
}
if (reader_a.Inst->Type == RC_INSTRUCTION_PAIR
&& reader_b.Inst->Type == RC_INSTRUCTION_PAIR
&& reader_a.U.P.Src == reader_b.U.P.Src) {
return 1;
}
}
}
return 0;
}
void rc_variable_add_friend(
struct rc_variable * var,
struct rc_variable * friend)
{
assert(var
->Dst.
Index == friend
->Dst.
Index); while(var->Friend) {
var = var->Friend;
}
var->Friend = friend;
}
struct rc_variable * rc_variable(
struct radeon_compiler * c,
unsigned int DstFile,
unsigned int DstIndex,
unsigned int DstWriteMask,
struct rc_reader_data * reader_data)
{
struct rc_variable * new =
memory_pool_malloc(&c->Pool, sizeof(struct rc_variable));
memset(new
, 0, sizeof(struct rc_variable
)); new->C = c;
new->Dst.File = DstFile;
new->Dst.Index = DstIndex;
new->Dst.WriteMask = DstWriteMask;
if (reader_data) {
new->Inst = reader_data->Writer;
new->ReaderCount = reader_data->ReaderCount;
new->Readers = reader_data->Readers;
}
return new;
}
static void get_variable_helper(
struct rc_list ** variable_list,
struct rc_variable * variable)
{
struct rc_list * list_ptr;
for (list_ptr = *variable_list; list_ptr; list_ptr = list_ptr->Next) {
struct rc_variable * var;
for (var = list_ptr->Item; var; var = var->Friend) {
if (readers_intersect(var, variable)) {
rc_variable_add_friend(var, variable);
return;
}
}
}
rc_list_add(variable_list, rc_list(&variable->C->Pool, variable));
}
static void get_variable_pair_helper(
struct rc_list ** variable_list,
struct radeon_compiler * c,
struct rc_instruction * inst,
struct rc_pair_sub_instruction * sub_inst)
{
struct rc_reader_data reader_data;
struct rc_variable * new_var;
rc_register_file file;
unsigned int writemask;
if (sub_inst->Opcode == RC_OPCODE_NOP) {
return;
}
memset(&reader_data
, 0, sizeof(struct rc_reader_data
)); rc_get_readers_sub(c, inst, sub_inst, &reader_data, NULL, NULL, NULL);
if (reader_data.ReaderCount == 0) {
return;
}
if (sub_inst->WriteMask) {
file = RC_FILE_TEMPORARY;
writemask = sub_inst->WriteMask;
} else if (sub_inst->OutputWriteMask) {
file = RC_FILE_OUTPUT;
writemask = sub_inst->OutputWriteMask;
} else {
writemask = 0;
file = RC_FILE_NONE;
}
new_var = rc_variable(c, file, sub_inst->DestIndex, writemask,
&reader_data);
get_variable_helper(variable_list, new_var);
}
/**
* Generate a list of variables used by the shader program. Each instruction
* that writes to a register is considered a variable. The struct rc_variable
* data structure includes a list of readers and is essentially a
* definition-use chain. Any two variables that share a reader are considered
* "friends" and they are linked together via the Friend attribute.
*/
struct rc_list * rc_get_variables(struct radeon_compiler * c)
{
struct rc_instruction * inst;
struct rc_list * variable_list = NULL;
for (inst = c->Program.Instructions.Next;
inst != &c->Program.Instructions;
inst = inst->Next) {
struct rc_reader_data reader_data;
struct rc_variable * new_var;
memset(&reader_data
, 0, sizeof(reader_data
));
if (inst->Type == RC_INSTRUCTION_NORMAL) {
rc_get_readers(c, inst, &reader_data, NULL, NULL, NULL);
if (reader_data.ReaderCount == 0) {
continue;
}
new_var = rc_variable(c, inst->U.I.DstReg.File,
inst->U.I.DstReg.Index,
inst->U.I.DstReg.WriteMask, &reader_data);
get_variable_helper(&variable_list, new_var);
} else {
get_variable_pair_helper(&variable_list, c, inst,
&inst->U.P.RGB);
get_variable_pair_helper(&variable_list, c, inst,
&inst->U.P.Alpha);
}
}
return variable_list;
}
/**
* @return The bitwise or of the writemasks of a variable and all of its
* friends.
*/
unsigned int rc_variable_writemask_sum(struct rc_variable * var)
{
unsigned int writemask = 0;
while(var) {
writemask |= var->Dst.WriteMask;
var = var->Friend;
}
return writemask;
}
/*
* @return A list of readers for a variable and its friends. Readers
* that read from two different variable friends are only included once in
* this list.
*/
struct rc_list * rc_variable_readers_union(struct rc_variable * var)
{
struct rc_list * list = NULL;
while (var) {
unsigned int i;
for (i = 0; i < var->ReaderCount; i++) {
struct rc_list * temp;
struct rc_reader * a = &var->Readers[i];
unsigned int match = 0;
for (temp = list; temp; temp = temp->Next) {
struct rc_reader * b = temp->Item;
if (a->Inst->Type != b->Inst->Type) {
continue;
}
if (a->Inst->Type == RC_INSTRUCTION_NORMAL) {
if (a->U.I.Src == b->U.I.Src) {
match = 1;
break;
}
}
if (a->Inst->Type == RC_INSTRUCTION_PAIR) {
if (a->U.P.Arg == b->U.P.Arg
&& a->U.P.Src == b->U.P.Src) {
match = 1;
break;
}
}
}
if (match) {
continue;
}
rc_list_add(&list, rc_list(&var->C->Pool, a));
}
var = var->Friend;
}
return list;
}
static unsigned int reader_equals_src(
struct rc_reader reader,
unsigned int src_type,
void * src)
{
if (reader.Inst->Type != src_type) {
return 0;
}
if (src_type == RC_INSTRUCTION_NORMAL) {
return reader.U.I.Src == src;
} else {
return reader.U.P.Src == src;
}
}
static unsigned int variable_writes_src(
struct rc_variable * var,
unsigned int src_type,
void * src)
{
unsigned int i;
for (i = 0; i < var->ReaderCount; i++) {
if (reader_equals_src(var->Readers[i], src_type, src)) {
return 1;
}
}
return 0;
}
struct rc_list * rc_variable_list_get_writers(
struct rc_list * var_list,
unsigned int src_type,
void * src)
{
struct rc_list * list_ptr;
struct rc_list * writer_list = NULL;
for (list_ptr = var_list; list_ptr; list_ptr = list_ptr->Next) {
struct rc_variable * var = list_ptr->Item;
if (variable_writes_src(var, src_type, src)) {
struct rc_variable * friend;
rc_list_add(&writer_list, rc_list(&var->C->Pool, var));
for (friend = var->Friend; friend;
friend = friend->Friend) {
if (variable_writes_src(friend, src_type, src)) {
rc_list_add(&writer_list,
rc_list(&var->C->Pool, friend));
}
}
/* Once we have indentifed the variable and its
* friends that write this source, we can stop
* stop searching, because we know none of the
* other variables in the list will write this source.
* If they did they would be friends of var.
*/
break;
}
}
return writer_list;
}
struct rc_list * rc_variable_list_get_writers_one_reader(
struct rc_list * var_list,
unsigned int src_type,
void * src)
{
struct rc_list * writer_list =
rc_variable_list_get_writers(var_list, src_type, src);
struct rc_list * reader_list =
rc_variable_readers_union(writer_list->Item);
if (rc_list_count(reader_list) > 1) {
return NULL;
} else {
return writer_list;
}
}
void rc_variable_print(struct rc_variable * var)
{
unsigned int i;
while (var) {
fprintf(stderr
, "%u: TEMP[%u].%u: ", var->Inst->IP, var->Dst.Index, var->Dst.WriteMask);
for (i = 0; i < 4; i++) {
fprintf(stderr
, "chan %u: start=%u end=%u ", i
, var->Live[i].Start, var->Live[i].End);
}
fprintf(stderr
, "%u readers\n", var
->ReaderCount
); if (var->Friend) {
}
var = var->Friend;
}
}