[Mesa-dev] [PATCH] ac: Use mov_dpp for derivatives.
Bas Nieuwenhuizen
bas at basnieuwenhuizen.nl
Sat Jun 10 20:05:30 UTC 2017
Slightly faster than bpermute, and seems supported since at least
LLVM 3.9.
v2: Since this supersedes bpermute, remove the bpermute code.
Signed-off-by: Bas Nieuwenhuizen <basni at google.com>
---
src/amd/common/ac_llvm_build.c | 47 ++++++++++++++++++++------------
src/amd/common/ac_llvm_build.h | 2 +-
src/amd/common/ac_nir_to_llvm.c | 8 +++---
src/gallium/drivers/radeonsi/si_pipe.c | 2 +-
src/gallium/drivers/radeonsi/si_pipe.h | 2 +-
src/gallium/drivers/radeonsi/si_shader.c | 4 +--
6 files changed, 38 insertions(+), 27 deletions(-)
diff --git a/src/amd/common/ac_llvm_build.c b/src/amd/common/ac_llvm_build.c
index 237e9291d41..99d41bf52d6 100644
--- a/src/amd/common/ac_llvm_build.c
+++ b/src/amd/common/ac_llvm_build.c
@@ -783,41 +783,52 @@ ac_get_thread_id(struct ac_llvm_context *ctx)
*/
LLVMValueRef
ac_build_ddxy(struct ac_llvm_context *ctx,
- bool has_ds_bpermute,
+ bool has_mov_dpp,
uint32_t mask,
int idx,
LLVMValueRef lds,
LLVMValueRef val)
{
- LLVMValueRef thread_id, tl, trbl, tl_tid, trbl_tid, args[2];
+ LLVMValueRef thread_id, tl, trbl, args[5];
LLVMValueRef result;
- thread_id = ac_get_thread_id(ctx);
+ if (has_mov_dpp) {
+ uint32_t tl_ctrl = 0, trbl_ctrl = 0;
- tl_tid = LLVMBuildAnd(ctx->builder, thread_id,
- LLVMConstInt(ctx->i32, mask, false), "");
-
- trbl_tid = LLVMBuildAdd(ctx->builder, tl_tid,
- LLVMConstInt(ctx->i32, idx, false), "");
+ for (unsigned i = 0; i < 4; ++i) {
+ tl_ctrl |= (i & mask) << (2 * i);
+ trbl_ctrl |= ((i & mask) + idx) << (2 * i);
+ }
- if (has_ds_bpermute) {
- args[0] = LLVMBuildMul(ctx->builder, tl_tid,
- LLVMConstInt(ctx->i32, 4, false), "");
- args[1] = val;
+ args[0] = val;
+ args[1] = LLVMConstInt(ctx->i32, tl_ctrl, false);
+ args[2] = LLVMConstInt(ctx->i32, 0xf, false);
+ args[3] = LLVMConstInt(ctx->i32, 0xf, false);
+ args[4] = LLVMConstInt(ctx->i1, 1, false);
tl = ac_build_intrinsic(ctx,
- "llvm.amdgcn.ds.bpermute", ctx->i32,
- args, 2,
+ "llvm.amdgcn.mov.dpp.i32", ctx->i32,
+ args, 5,
AC_FUNC_ATTR_READNONE |
AC_FUNC_ATTR_CONVERGENT);
- args[0] = LLVMBuildMul(ctx->builder, trbl_tid,
- LLVMConstInt(ctx->i32, 4, false), "");
+ args[1] = LLVMConstInt(ctx->i32, trbl_ctrl, false);
trbl = ac_build_intrinsic(ctx,
- "llvm.amdgcn.ds.bpermute", ctx->i32,
- args, 2,
+ "llvm.amdgcn.mov.dpp.i32", ctx->i32,
+ args, 5,
AC_FUNC_ATTR_READNONE |
AC_FUNC_ATTR_CONVERGENT);
} else {
+ LLVMValueRef tl_tid, trbl_tid;
+
+ thread_id = ac_get_thread_id(ctx);
+
+ tl_tid = LLVMBuildAnd(ctx->builder, thread_id,
+ LLVMConstInt(ctx->i32, mask, false), "");
+
+ trbl_tid = LLVMBuildAdd(ctx->builder, tl_tid,
+ LLVMConstInt(ctx->i32, idx, false), "");
+
+
LLVMValueRef store_ptr, load_ptr0, load_ptr1;
store_ptr = ac_build_gep0(ctx, lds, thread_id);
diff --git a/src/amd/common/ac_llvm_build.h b/src/amd/common/ac_llvm_build.h
index ebb78fbd79b..14260b05018 100644
--- a/src/amd/common/ac_llvm_build.h
+++ b/src/amd/common/ac_llvm_build.h
@@ -161,7 +161,7 @@ ac_get_thread_id(struct ac_llvm_context *ctx);
LLVMValueRef
ac_build_ddxy(struct ac_llvm_context *ctx,
- bool has_ds_bpermute,
+ bool has_mov_dpp,
uint32_t mask,
int idx,
LLVMValueRef lds,
diff --git a/src/amd/common/ac_nir_to_llvm.c b/src/amd/common/ac_nir_to_llvm.c
index 49117d21bd2..2385c60d316 100644
--- a/src/amd/common/ac_nir_to_llvm.c
+++ b/src/amd/common/ac_nir_to_llvm.c
@@ -164,7 +164,7 @@ struct nir_to_llvm_context {
uint8_t num_output_clips;
uint8_t num_output_culls;
- bool has_ds_bpermute;
+ bool has_mov_dpp;
bool is_gs_copy_shader;
LLVMValueRef gs_next_vertex;
@@ -1434,7 +1434,7 @@ static LLVMValueRef emit_ddxy(struct nir_to_llvm_context *ctx,
LLVMValueRef result;
ctx->has_ddxy = true;
- if (!ctx->lds && !ctx->has_ds_bpermute)
+ if (!ctx->lds && !ctx->has_mov_dpp)
ctx->lds = LLVMAddGlobalInAddressSpace(ctx->module,
LLVMArrayType(ctx->i32, 64),
"ddxy_lds", LOCAL_ADDR_SPACE);
@@ -1454,7 +1454,7 @@ static LLVMValueRef emit_ddxy(struct nir_to_llvm_context *ctx,
else
idx = 2;
- result = ac_build_ddxy(&ctx->ac, ctx->has_ds_bpermute,
+ result = ac_build_ddxy(&ctx->ac, ctx->has_mov_dpp,
mask, idx, ctx->lds,
src0);
return result;
@@ -5858,7 +5858,7 @@ LLVMModuleRef ac_translate_nir_to_llvm(LLVMTargetMachineRef tm,
ac_llvm_context_init(&ctx.ac, ctx.context);
ctx.ac.module = ctx.module;
- ctx.has_ds_bpermute = ctx.options->chip_class >= VI;
+ ctx.has_mov_dpp = ctx.options->chip_class >= VI;
memset(shader_info, 0, sizeof(*shader_info));
diff --git a/src/gallium/drivers/radeonsi/si_pipe.c b/src/gallium/drivers/radeonsi/si_pipe.c
index cb372267cde..7e83d5e5ac4 100644
--- a/src/gallium/drivers/radeonsi/si_pipe.c
+++ b/src/gallium/drivers/radeonsi/si_pipe.c
@@ -944,7 +944,7 @@ struct pipe_screen *radeonsi_screen_create(struct radeon_winsys *ws)
sscreen->b.info.pfp_fw_version >= 121 &&
sscreen->b.info.me_fw_version >= 87);
- sscreen->has_ds_bpermute = sscreen->b.chip_class >= VI;
+ sscreen->has_mov_dpp = sscreen->b.chip_class >= VI;
sscreen->has_msaa_sample_loc_bug = (sscreen->b.family >= CHIP_POLARIS10 &&
sscreen->b.family <= CHIP_POLARIS12) ||
sscreen->b.family == CHIP_VEGA10 ||
diff --git a/src/gallium/drivers/radeonsi/si_pipe.h b/src/gallium/drivers/radeonsi/si_pipe.h
index 108929c10c6..ef139fb0cd3 100644
--- a/src/gallium/drivers/radeonsi/si_pipe.h
+++ b/src/gallium/drivers/radeonsi/si_pipe.h
@@ -79,7 +79,7 @@ struct si_screen {
unsigned tess_offchip_block_dw_size;
bool has_distributed_tess;
bool has_draw_indirect_multi;
- bool has_ds_bpermute;
+ bool has_mov_dpp;
bool has_msaa_sample_loc_bug;
/* Whether shaders are monolithic (1-part) or separate (3-part). */
diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c
index 2c92269a575..2eed45d79a5 100644
--- a/src/gallium/drivers/radeonsi/si_shader.c
+++ b/src/gallium/drivers/radeonsi/si_shader.c
@@ -3442,7 +3442,7 @@ static void si_llvm_emit_ddxy(
idx = (opcode == TGSI_OPCODE_DDX || opcode == TGSI_OPCODE_DDX_FINE) ? 1 : 2;
val = LLVMBuildBitCast(gallivm->builder, emit_data->args[0], ctx->i32, "");
- val = ac_build_ddxy(&ctx->ac, ctx->screen->has_ds_bpermute,
+ val = ac_build_ddxy(&ctx->ac, ctx->screen->has_mov_dpp,
mask, idx, ctx->lds, val);
emit_data->output[emit_data->chan] = val;
}
@@ -4454,7 +4454,7 @@ static void create_function(struct si_shader_context *ctx)
assert(shader->info.num_input_vgprs >= num_prolog_vgprs);
shader->info.num_input_vgprs -= num_prolog_vgprs;
- if (!ctx->screen->has_ds_bpermute &&
+ if (!ctx->screen->has_mov_dpp &&
bld_base->info &&
(bld_base->info->opcode_count[TGSI_OPCODE_DDX] > 0 ||
bld_base->info->opcode_count[TGSI_OPCODE_DDY] > 0 ||
--
2.13.0
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