[Mesa-dev] [PATCH 07/25] i965/fs: Implement opt_sampler_eot() in terms of logical sends.
Francisco Jerez
currojerez at riseup.net
Sat May 28 02:05:48 UTC 2016
This makes the whole LOAD_PAYLOAD munging unnecessary which simplifies
the code and will allow the optimization to succeed in more cases
independent of whether the LOAD_PAYLOAD instruction can be found or
not.
---
src/mesa/drivers/dri/i965/brw_fs.cpp | 79 +++++++++++-------------------------
1 file changed, 23 insertions(+), 56 deletions(-)
diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
index 45c4753..6abf776 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
@@ -2612,11 +2612,15 @@ fs_visitor::opt_sampler_eot()
if (key->nr_color_regions != 1)
return false;
+ /* Requires clamping the color payload in the shader. */
+ if (key->clamp_fragment_color)
+ return false;
+
/* Look for a texturing instruction immediately before the final FB_WRITE. */
bblock_t *block = cfg->blocks[cfg->num_blocks - 1];
fs_inst *fb_write = (fs_inst *)block->end();
assert(fb_write->eot);
- assert(fb_write->opcode == FS_OPCODE_FB_WRITE);
+ assert(fb_write->opcode == FS_OPCODE_FB_WRITE_LOGICAL);
/* There wasn't one; nothing to do. */
if (unlikely(fb_write->prev->is_head_sentinel()))
@@ -2629,24 +2633,20 @@ fs_visitor::opt_sampler_eot()
* “Response Length of zero is allowed on all SIMD8* and SIMD16* sampler
* messages except sample+killpix, resinfo, sampleinfo, LOD, and gather4*”
*/
- if (!tex_inst->is_tex() ||
- tex_inst->opcode == SHADER_OPCODE_TXS ||
- tex_inst->opcode == SHADER_OPCODE_SAMPLEINFO ||
- tex_inst->opcode == SHADER_OPCODE_LOD ||
- tex_inst->opcode == SHADER_OPCODE_TG4 ||
- tex_inst->opcode == SHADER_OPCODE_TG4_OFFSET)
+ if (tex_inst->opcode != SHADER_OPCODE_TEX_LOGICAL &&
+ tex_inst->opcode != SHADER_OPCODE_TXD_LOGICAL &&
+ tex_inst->opcode != SHADER_OPCODE_TXF_LOGICAL &&
+ tex_inst->opcode != SHADER_OPCODE_TXL_LOGICAL &&
+ tex_inst->opcode != FS_OPCODE_TXB_LOGICAL &&
+ tex_inst->opcode != SHADER_OPCODE_TXF_CMS_LOGICAL &&
+ tex_inst->opcode != SHADER_OPCODE_TXF_CMS_W_LOGICAL &&
+ tex_inst->opcode != SHADER_OPCODE_TXF_UMS_LOGICAL)
return false;
- /* If there's no header present, we need to munge the LOAD_PAYLOAD as well.
- * It's very likely to be the previous instruction.
- */
+ /* XXX - This shouldn't be necessary. */
if (tex_inst->prev->is_head_sentinel())
return false;
- fs_inst *load_payload = (fs_inst *) tex_inst->prev;
- if (load_payload->opcode != SHADER_OPCODE_LOAD_PAYLOAD)
- return false;
-
assert(!tex_inst->eot); /* We can't get here twice */
assert((tex_inst->offset & (0xff << 24)) == 0);
@@ -2658,46 +2658,10 @@ fs_visitor::opt_sampler_eot()
tex_inst->regs_written = 0;
fb_write->remove(cfg->blocks[cfg->num_blocks - 1]);
- /* If a header is present, marking the eot is sufficient. Otherwise, we need
- * to create a new LOAD_PAYLOAD command with the same sources and a space
- * saved for the header. Using a new destination register not only makes sure
- * we have enough space, but it will make sure the dead code eliminator kills
- * the instruction that this will replace.
+ /* Marking EOT is sufficient, lower_logical_sends() will notice the EOT
+ * flag and submit a header together with the sampler message as required
+ * by the hardware.
*/
- if (tex_inst->header_size != 0) {
- invalidate_live_intervals();
- return true;
- }
-
- fs_reg send_header = ibld.vgrf(BRW_REGISTER_TYPE_F,
- load_payload->sources + 1);
- fs_reg *new_sources =
- ralloc_array(mem_ctx, fs_reg, load_payload->sources + 1);
-
- new_sources[0] = fs_reg();
- for (int i = 0; i < load_payload->sources; i++)
- new_sources[i+1] = load_payload->src[i];
-
- /* The LOAD_PAYLOAD helper seems like the obvious choice here. However, it
- * requires a lot of information about the sources to appropriately figure
- * out the number of registers needed to be used. Given this stage in our
- * optimization, we may not have the appropriate GRFs required by
- * LOAD_PAYLOAD at this point (copy propagation). Therefore, we need to
- * manually emit the instruction.
- */
- fs_inst *new_load_payload = new(mem_ctx) fs_inst(SHADER_OPCODE_LOAD_PAYLOAD,
- load_payload->exec_size,
- send_header,
- new_sources,
- load_payload->sources + 1);
-
- new_load_payload->regs_written = load_payload->regs_written + 1;
- new_load_payload->header_size = 1;
- tex_inst->mlen++;
- tex_inst->header_size = 1;
- tex_inst->insert_before(cfg->blocks[cfg->num_blocks - 1], new_load_payload);
- tex_inst->src[0] = send_header;
-
invalidate_live_intervals();
return true;
}
@@ -4153,7 +4117,7 @@ lower_sampler_logical_send_gen7(const fs_builder &bld, fs_inst *inst, opcode op,
sources[i] = bld.vgrf(BRW_REGISTER_TYPE_F);
if (op == SHADER_OPCODE_TG4 || op == SHADER_OPCODE_TG4_OFFSET ||
- offset_value.file != BAD_FILE ||
+ offset_value.file != BAD_FILE || inst->eot ||
op == SHADER_OPCODE_SAMPLEINFO ||
is_high_sampler(devinfo, sampler)) {
/* For general texture offsets (no txf workaround), we need a header to
@@ -4174,7 +4138,7 @@ lower_sampler_logical_send_gen7(const fs_builder &bld, fs_inst *inst, opcode op,
* and we have an explicit header, we need to set up the sampler
* writemask. It's reversed from normal: 1 means "don't write".
*/
- if (inst->regs_written != 4 * reg_width) {
+ if (!inst->eot && inst->regs_written != 4 * reg_width) {
assert((inst->regs_written % reg_width) == 0);
unsigned mask = ~((1 << (inst->regs_written / reg_width)) - 1) & 0xf;
inst->offset |= mask << 12;
@@ -5738,6 +5702,10 @@ fs_visitor::optimize()
pass_num = 0;
OPT(lower_simd_width);
+
+ /* After SIMD lowering just in case we had to unroll the EOT send. */
+ OPT(opt_sampler_eot);
+
OPT(lower_logical_sends);
if (progress) {
@@ -5761,7 +5729,6 @@ fs_visitor::optimize()
}
OPT(opt_redundant_discard_jumps);
- OPT(opt_sampler_eot);
if (OPT(lower_load_payload)) {
split_virtual_grfs();
--
2.7.3
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