radeonsi: use PS epilog for monolithic shaders
authorNicolai Hähnle <nicolai.haehnle@amd.com>
Fri, 28 Oct 2016 12:45:59 +0000 (14:45 +0200)
committerNicolai Hähnle <nicolai.haehnle@amd.com>
Thu, 3 Nov 2016 09:07:00 +0000 (10:07 +0100)
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
src/gallium/drivers/radeonsi/si_shader.c

index ec5f95044893b3db9c4aae699aa6b7c6c9ee68e2..281a4dd26c7e44143d4dded77dc886c19794292c 100644 (file)
@@ -40,6 +40,7 @@
 #include "tgsi/tgsi_util.h"
 #include "tgsi/tgsi_dump.h"
 
+#include "ac_llvm_util.h"
 #include "si_shader_internal.h"
 #include "si_pipe.h"
 #include "sid.h"
@@ -70,6 +71,9 @@ static void si_llvm_emit_barrier(const struct lp_build_tgsi_action *action,
 static void si_dump_shader_key(unsigned shader, union si_shader_key *key,
                               FILE *f);
 
+static void si_build_ps_epilog_function(struct si_shader_context *ctx,
+                                       union si_shader_part_key *key);
+
 /* Ideally pass the sample mask input to the PS epilog as v13, which
  * is its usual location, so that the shader doesn't have to add v_mov.
  */
@@ -6774,6 +6778,193 @@ static void si_get_ps_epilog_key(struct si_shader *shader,
        key->ps_epilog.states = shader->key.ps.epilog;
 }
 
+/**
+ * Given a list of shader part functions, build a wrapper function that
+ * runs them in sequence to form a monolithic shader.
+ */
+static void si_build_wrapper_function(struct si_shader_context *ctx,
+                                     LLVMValueRef *parts,
+                                     unsigned num_parts,
+                                     unsigned main_part)
+{
+       struct gallivm_state *gallivm = &ctx->gallivm;
+       LLVMBuilderRef builder = ctx->gallivm.builder;
+       /* PS epilog has one arg per color component */
+       LLVMTypeRef param_types[48];
+       LLVMValueRef out[48];
+       LLVMTypeRef function_type;
+       unsigned num_params;
+       unsigned num_out_sgpr, num_out;
+       unsigned num_sgprs, num_vgprs;
+       unsigned last_sgpr_param;
+       unsigned gprs;
+
+       for (unsigned i = 0; i < num_parts; ++i) {
+               LLVMAddFunctionAttr(parts[i], LLVMAlwaysInlineAttribute);
+               LLVMSetLinkage(parts[i], LLVMPrivateLinkage);
+       }
+
+       /* The parameters of the wrapper function correspond to those of the
+        * first part in terms of SGPRs and VGPRs, but we use the types of the
+        * main part to get the right types. This is relevant for the
+        * dereferenceable attribute on descriptor table pointers.
+        */
+       num_sgprs = 0;
+       num_vgprs = 0;
+
+       function_type = LLVMGetElementType(LLVMTypeOf(parts[0]));
+       num_params = LLVMCountParamTypes(function_type);
+
+       for (unsigned i = 0; i < num_params; ++i) {
+               LLVMValueRef param = LLVMGetParam(parts[0], i);
+
+               if (ac_is_sgpr_param(param)) {
+                       assert(num_vgprs == 0);
+                       num_sgprs += llvm_get_type_size(LLVMTypeOf(param)) / 4;
+               } else {
+                       num_vgprs += llvm_get_type_size(LLVMTypeOf(param)) / 4;
+               }
+       }
+       assert(num_vgprs + num_sgprs <= ARRAY_SIZE(param_types));
+
+       num_params = 0;
+       last_sgpr_param = 0;
+       gprs = 0;
+       while (gprs < num_sgprs + num_vgprs) {
+               LLVMValueRef param = LLVMGetParam(parts[main_part], num_params);
+               unsigned size;
+
+               param_types[num_params] = LLVMTypeOf(param);
+               if (gprs < num_sgprs)
+                       last_sgpr_param = num_params;
+               size = llvm_get_type_size(param_types[num_params]) / 4;
+               num_params++;
+
+               assert(ac_is_sgpr_param(param) == (gprs < num_sgprs));
+               assert(gprs + size <= num_sgprs + num_vgprs &&
+                      (gprs >= num_sgprs || gprs + size <= num_sgprs));
+
+               gprs += size;
+       }
+
+       si_create_function(ctx, "wrapper", NULL, 0, param_types, num_params, last_sgpr_param);
+
+       /* Record the arguments of the function as if they were an output of
+        * a previous part.
+        */
+       num_out = 0;
+       num_out_sgpr = 0;
+
+       for (unsigned i = 0; i < num_params; ++i) {
+               LLVMValueRef param = LLVMGetParam(ctx->main_fn, i);
+               LLVMTypeRef param_type = LLVMTypeOf(param);
+               LLVMTypeRef out_type = i <= last_sgpr_param ? ctx->i32 : ctx->f32;
+               unsigned size = llvm_get_type_size(param_type) / 4;
+
+               if (size == 1) {
+                       if (param_type != out_type)
+                               param = LLVMBuildBitCast(builder, param, out_type, "");
+                       out[num_out++] = param;
+               } else {
+                       LLVMTypeRef vector_type = LLVMVectorType(out_type, size);
+
+                       if (LLVMGetTypeKind(param_type) == LLVMPointerTypeKind) {
+                               param = LLVMBuildPtrToInt(builder, param, ctx->i64, "");
+                               param_type = ctx->i64;
+                       }
+
+                       if (param_type != vector_type)
+                               param = LLVMBuildBitCast(builder, param, vector_type, "");
+
+                       for (unsigned j = 0; j < size; ++j)
+                               out[num_out++] = LLVMBuildExtractElement(
+                                       builder, param, LLVMConstInt(ctx->i32, j, 0), "");
+               }
+
+               if (i <= last_sgpr_param)
+                       num_out_sgpr = num_out;
+       }
+
+       /* Now chain the parts. */
+       for (unsigned part = 0; part < num_parts; ++part) {
+               LLVMValueRef in[48];
+               LLVMValueRef ret;
+               LLVMTypeRef ret_type;
+               unsigned out_idx = 0;
+
+               num_params = LLVMCountParams(parts[part]);
+               assert(num_params <= ARRAY_SIZE(param_types));
+
+               /* Derive arguments for the next part from outputs of the
+                * previous one.
+                */
+               for (unsigned param_idx = 0; param_idx < num_params; ++param_idx) {
+                       LLVMValueRef param;
+                       LLVMTypeRef param_type;
+                       bool is_sgpr;
+                       unsigned param_size;
+                       LLVMValueRef arg = NULL;
+
+                       param = LLVMGetParam(parts[part], param_idx);
+                       param_type = LLVMTypeOf(param);
+                       param_size = llvm_get_type_size(param_type) / 4;
+                       is_sgpr = ac_is_sgpr_param(param);
+
+                       if (is_sgpr) {
+                               LLVMRemoveAttribute(param, LLVMByValAttribute);
+                               LLVMAddAttribute(param, LLVMInRegAttribute);
+                       }
+
+                       assert(out_idx + param_size <= (is_sgpr ? num_out_sgpr : num_out));
+                       assert(is_sgpr || out_idx >= num_out_sgpr);
+
+                       if (param_size == 1)
+                               arg = out[out_idx];
+                       else
+                               arg = lp_build_gather_values(gallivm, &out[out_idx], param_size);
+
+                       if (LLVMTypeOf(arg) != param_type) {
+                               if (LLVMGetTypeKind(param_type) == LLVMPointerTypeKind) {
+                                       arg = LLVMBuildBitCast(builder, arg, ctx->i64, "");
+                                       arg = LLVMBuildIntToPtr(builder, arg, param_type, "");
+                               } else {
+                                       arg = LLVMBuildBitCast(builder, arg, param_type, "");
+                               }
+                       }
+
+                       in[param_idx] = arg;
+                       out_idx += param_size;
+               }
+
+               ret = LLVMBuildCall(builder, parts[part], in, num_params, "");
+               ret_type = LLVMTypeOf(ret);
+
+               /* Extract the returned GPRs. */
+               num_out = 0;
+               num_out_sgpr = 0;
+
+               if (LLVMGetTypeKind(ret_type) != LLVMVoidTypeKind) {
+                       assert(LLVMGetTypeKind(ret_type) == LLVMStructTypeKind);
+
+                       unsigned ret_size = LLVMCountStructElementTypes(ret_type);
+
+                       for (unsigned i = 0; i < ret_size; ++i) {
+                               LLVMValueRef val =
+                                       LLVMBuildExtractValue(builder, ret, i, "");
+
+                               out[num_out++] = val;
+
+                               if (LLVMTypeOf(val) == ctx->i32) {
+                                       assert(num_out_sgpr + 1 == num_out);
+                                       num_out_sgpr = num_out;
+                               }
+                       }
+               }
+       }
+
+       LLVMBuildRetVoid(builder);
+}
+
 int si_compile_tgsi_shader(struct si_screen *sscreen,
                           LLVMTargetMachineRef tm,
                           struct si_shader *shader,
@@ -6799,6 +6990,9 @@ int si_compile_tgsi_shader(struct si_screen *sscreen,
        ctx.no_epilog = is_monolithic;
        ctx.separate_prolog = !is_monolithic;
 
+       if (ctx.type == PIPE_SHADER_FRAGMENT)
+               ctx.no_epilog = false;
+
        memset(shader->info.vs_output_param_offset, 0xff,
               sizeof(shader->info.vs_output_param_offset));
 
@@ -6812,6 +7006,19 @@ int si_compile_tgsi_shader(struct si_screen *sscreen,
                return -1;
        }
 
+       if (is_monolithic && ctx.type == PIPE_SHADER_FRAGMENT) {
+               LLVMValueRef parts[2];
+               union si_shader_part_key epilog_key;
+
+               parts[0] = ctx.main_fn;
+
+               si_get_ps_epilog_key(shader, &epilog_key);
+               si_build_ps_epilog_function(&ctx, &epilog_key);
+               parts[1] = ctx.main_fn;
+
+               si_build_wrapper_function(&ctx, parts, 2, 0);
+       }
+
        mod = bld_base->base.gallivm->module;
 
        /* Dump LLVM IR before any optimization passes */