KonstantinSeurer
/
mesa
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

radeonsi: skip LDS stores in TCS if there are no LDS output reads 

This removes a lot of useless LDS stores.

A few games read TESSINNER/OUTER, but not any other outputs. Most games
don't read any outputs.

The only app doing LDS output reads is UE4 Lightsroom Interior.

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
This commit is contained in:
Marek Olšák 2017-02-18 15:30:25 +01:00
parent 58af0a5385
commit d633e23192
1 changed files with 16 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
src/gallium/drivers/radeonsi/si_shader.c
View File

@ -982,10 +982,12 @@ static void store_output_tcs(struct lp_build_tgsi_context *bld_base,
struct si_shader_context *ctx = si_shader_context(bld_base);
struct gallivm_state *gallivm = bld_base->base.gallivm;
const struct tgsi_full_dst_register *reg = &inst->Dst[0];
const struct tgsi_shader_info *sh_info = &ctx->shader->selector->info;
unsigned chan_index;
LLVMValueRef dw_addr, stride;
LLVMValueRef rw_buffers, buffer, base, buf_addr;
LLVMValueRef values[4];
bool skip_lds_store;
/* Only handle per-patch and per-vertex outputs here.
* Vectors will be lowered to scalars and this function will be called again.
@ -1000,9 +1002,20 @@ static void store_output_tcs(struct lp_build_tgsi_context *bld_base,
stride = unpack_param(ctx, SI_PARAM_TCS_OUT_LAYOUT, 13, 8);
dw_addr = get_tcs_out_current_patch_offset(ctx);
dw_addr = get_dw_address(ctx, reg, NULL, stride, dw_addr);
skip_lds_store = !sh_info->reads_pervertex_outputs;
} else {
dw_addr = get_tcs_out_current_patch_data_offset(ctx);
dw_addr = get_dw_address(ctx, reg, NULL, NULL, dw_addr);
skip_lds_store = !sh_info->reads_perpatch_outputs;
if (!reg->Register.Indirect) {
int name = sh_info->output_semantic_name[reg->Register.Index];
/* Always write tess factors into LDS for the TCS epilog. */
if (name == TGSI_SEMANTIC_TESSINNER ||
name == TGSI_SEMANTIC_TESSOUTER)
skip_lds_store = false;
}
}
rw_buffers = LLVMGetParam(ctx->main_fn,
@ -1020,7 +1033,9 @@ static void store_output_tcs(struct lp_build_tgsi_context *bld_base,
if (inst->Instruction.Saturate)
value = ac_emit_clamp(&ctx->ac, value);
lds_store(bld_base, chan_index, dw_addr, value);
/* Skip LDS stores if there is no LDS read of this output. */
if (!skip_lds_store)
lds_store(bld_base, chan_index, dw_addr, value);
value = LLVMBuildBitCast(gallivm->builder, value, ctx->i32, "");
values[chan_index] = value;