diff options
Diffstat (limited to 'src/mesa/drivers/dri/r300/compiler/radeon_dataflow.c')
-rw-r--r-- | src/mesa/drivers/dri/r300/compiler/radeon_dataflow.c | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/src/mesa/drivers/dri/r300/compiler/radeon_dataflow.c b/src/mesa/drivers/dri/r300/compiler/radeon_dataflow.c index a27d395587..5927498818 100644 --- a/src/mesa/drivers/dri/r300/compiler/radeon_dataflow.c +++ b/src/mesa/drivers/dri/r300/compiler/radeon_dataflow.c @@ -1,5 +1,6 @@ /* * Copyright (C) 2009 Nicolai Haehnle. + * Copyright 2010 Tom Stellard <tstellar@gmail.com> * * All Rights Reserved. * @@ -27,6 +28,8 @@ #include "radeon_dataflow.h" +#include "radeon_compiler.h" +#include "radeon_compiler_util.h" #include "radeon_program.h" struct read_write_mask_data { @@ -402,3 +405,252 @@ void rc_remap_registers(struct rc_instruction * inst, rc_remap_register_fn cb, v else remap_pair_instruction(inst, cb, userdata); } + +/** + * @return RC_OPCODE_NOOP if inst is not a flow control instruction. + * @return The opcode of inst if it is a flow control instruction. + */ +static rc_opcode get_flow_control_inst(struct rc_instruction * inst) +{ + const struct rc_opcode_info * info; + if (inst->Type == RC_INSTRUCTION_NORMAL) { + info = rc_get_opcode_info(inst->U.I.Opcode); + } else { + info = rc_get_opcode_info(inst->U.P.RGB.Opcode); + /*A flow control instruction shouldn't have an alpha + * instruction.*/ + assert(!info->IsFlowControl || + inst->U.P.Alpha.Opcode == RC_OPCODE_NOP); + } + + if (info->IsFlowControl) + return info->Opcode; + else + return RC_OPCODE_NOP; + +} + +struct get_readers_callback_data { + struct radeon_compiler * C; + struct rc_reader_data * ReaderData; + rc_read_src_fn ReadCB; + rc_read_write_mask_fn WriteCB; + unsigned int AliveWriteMask; +}; + +static void add_reader( + struct memory_pool * pool, + struct rc_reader_data * data, + struct rc_instruction * inst, + unsigned int mask, + struct rc_src_register * src) +{ + struct rc_reader * new; + memory_pool_array_reserve(pool, struct rc_reader, data->Readers, + data->ReaderCount, data->ReadersReserved, 1); + new = &data->Readers[data->ReaderCount++]; + new->Inst = inst; + new->WriteMask = mask; + new->Src = src; +} + +/** + * This function is used by rc_get_readers_normal() to determine whether inst + * is a reader of userdata->ReaderData->Writer + */ +static void get_readers_normal_read_callback( + void * userdata, + struct rc_instruction * inst, + struct rc_src_register * src) +{ + struct get_readers_callback_data * d = userdata; + unsigned int read_mask; + + if (src->RelAddr) + d->ReaderData->Abort = 1; + + unsigned int shared_mask = rc_src_reads_dst_mask(src->File, src->Index, + src->Swizzle, + d->ReaderData->Writer->U.I.DstReg.File, + d->ReaderData->Writer->U.I.DstReg.Index, + d->AliveWriteMask); + + if (shared_mask == RC_MASK_NONE) + return; + + /* If we make it this far, it means that this source reads from the + * same register written to by d->ReaderData->Writer. */ + + if (d->ReaderData->AbortOnRead) { + d->ReaderData->Abort = 1; + return; + } + + read_mask = rc_swizzle_to_writemask(src->Swizzle); + /* XXX The behavior in this case should be configurable. */ + if ((read_mask & d->AliveWriteMask) != read_mask) { + d->ReaderData->Abort = 1; + return; + } + + d->ReadCB(d->ReaderData, inst, src); + if (d->ReaderData->Abort) + return; + + add_reader(&d->C->Pool, d->ReaderData, inst, shared_mask, src); +} + +/** + * This function is used by rc_get_readers_normal() to determine when + * userdata->ReaderData->Writer is dead (i. e. All compontents of its + * destination register have been overwritten by other instructions). + */ +static void get_readers_write_callback( + void *userdata, + struct rc_instruction * inst, + rc_register_file file, + unsigned int index, + unsigned int mask) +{ + struct get_readers_callback_data * d = userdata; + + if (index == d->ReaderData->Writer->U.I.DstReg.Index + && file == d->ReaderData->Writer->U.I.DstReg.File) { + unsigned int shared_mask = mask + & d->ReaderData->Writer->U.I.DstReg.WriteMask; + if (d->ReaderData->InElse) { + if (shared_mask & d->AliveWriteMask) { + /* We set AbortOnRead here because the + * destination register of d->ReaderData->Writer + * is written to in both the IF and the + * ELSE block of this IF/ELSE statement. + * This means that readers of this + * destination register that follow this IF/ELSE + * statement use the value of different + * instructions depending on the control flow + * decisions made by the program. */ + d->ReaderData->AbortOnRead = 1; + } + } else { + d->AliveWriteMask &= ~shared_mask; + } + } + + d->WriteCB(d->ReaderData, inst, file, index, mask); +} + +/** + * This function will create a list of readers via the rc_reader_data struct. + * This function will abort (set the flag data->Abort) and return if it + * encounters an instruction that reads from @param writer and also a different + * instruction. Here are some examples: + * + * writer = instruction 0; + * 0 MOV TEMP[0].xy, TEMP[1].xy + * 1 MOV TEMP[0].zw, TEMP[2].xy + * 2 MOV TEMP[3], TEMP[0] + * The Abort flag will be set on instruction 2, because it reads values written + * by instructions 0 and 1. + * + * writer = instruction 1; + * 0 IF TEMP[0].x + * 1 MOV TEMP[1], TEMP[2] + * 2 ELSE + * 3 MOV TEMP[1], TEMP[2] + * 4 ENDIF + * 5 MOV TEMP[3], TEMP[1] + * The Abort flag will be set on instruction 5, because it could read from the + * value written by either instruction 1 or 3, depending on the jump decision + * made at instruction 0. + * + * writer = instruction 0; + * 0 MOV TEMP[0], TEMP[1] + * 2 BGNLOOP + * 3 ADD TEMP[0], TEMP[0], none.1 + * 4 ENDLOOP + * The Abort flag will be set on instruction 3, because in the first iteration + * of the loop it reads the value written by instruction 0 and in all other + * iterations it reads the value written by instruction 3. + * + * @param read_cb This function will be called for for every instruction that + * has been determined to be a reader of writer. + * @param write_cb This function will be called for every instruction after + * writer. + */ +void rc_get_readers_normal( + struct radeon_compiler * c, + struct rc_instruction * writer, + struct rc_reader_data * data, + rc_read_src_fn read_cb, + rc_read_write_mask_fn write_cb) +{ + struct rc_instruction * tmp; + struct get_readers_callback_data d; + unsigned int branch_depth = 0; + + data->Writer = writer; + data->Abort = 0; + data->AbortOnRead = 0; + data->InElse = 0; + data->ReaderCount = 0; + data->ReadersReserved = 0; + data->Readers = NULL; + + d.C = c; + d.AliveWriteMask = writer->U.I.DstReg.WriteMask; + d.ReaderData = data; + d.ReadCB = read_cb; + d.WriteCB = write_cb; + + if (!writer->U.I.DstReg.WriteMask) + return; + + for(tmp = writer->Next; tmp != &c->Program.Instructions; + tmp = tmp->Next){ + rc_opcode opcode = get_flow_control_inst(tmp); + switch(opcode) { + case RC_OPCODE_BGNLOOP: + /* XXX We can do better when we see a BGNLOOP if we + * add a flag called AbortOnWrite to struct + * rc_reader_data and leave it set until the next + * ENDLOOP. */ + case RC_OPCODE_ENDLOOP: + /* XXX We can do better when we see an ENDLOOP by + * searching backwards from writer and looking for + * readers of writer's destination index. If we find a + * reader before we get to the BGNLOOP, we must abort + * unless there is another writer between that reader + * and the BGNLOOP. */ + data->Abort = 1; + return; + case RC_OPCODE_IF: + branch_depth++; + break; + case RC_OPCODE_ELSE: + if (branch_depth == 0) + data->InElse = 1; + break; + case RC_OPCODE_ENDIF: + if (branch_depth == 0) { + data->AbortOnRead = 1; + data->InElse = 0; + } + else { + branch_depth--; + } + break; + default: + break; + } + + if (!data->InElse) + rc_for_all_reads_src(tmp, get_readers_normal_read_callback, &d); + rc_for_all_writes_mask(tmp, get_readers_write_callback, &d); + + if (data->Abort) + return; + + if (!d.AliveWriteMask) + return; + } +} |