st/mesa: implement DrawPixels shader transformation using tgsi_transform_shader

Reviewed-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Tested-by: Brian Paul <brianp@vmware.com>

1 files changed, 255 insertions, 0 deletions

diff --git a/src/mesa/state_tracker/st_cb_drawpixels_shader.c b/src/mesa/state_tracker/st_cb_drawpixels_shader.c
new file mode 100644
index 0000000..01db0b6
--- /dev/null
+++ b/src/mesa/state_tracker/st_cb_drawpixels_shader.c
@@ -0,0 +1,255 @@
+/**************************************************************************
+ *
+ * Copyright (C) 2015 Advanced Micro Devices, Inc.
+ * Copyright 2007 VMware, Inc.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
+ * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ **************************************************************************/
+
+#include "st_cb_drawpixels.h"
+#include "tgsi/tgsi_transform.h"
+#include "tgsi/tgsi_scan.h"
+
+struct tgsi_drawpix_transform {
+   struct tgsi_transform_context base;
+   struct tgsi_shader_info info;
+   bool use_texcoord;
+   bool scale_and_bias;
+   bool pixel_maps;
+   bool first_instruction_emitted;
+   unsigned scale_const;
+   unsigned bias_const;
+   unsigned color_temp;
+};
+
+static inline struct tgsi_drawpix_transform *
+tgsi_drawpix_transform(struct tgsi_transform_context *tctx)
+{
+   return (struct tgsi_drawpix_transform *)tctx;
+}
+
+static void
+set_src(struct tgsi_full_instruction *inst, unsigned i, unsigned file, unsigned index,
+        unsigned x, unsigned y, unsigned z, unsigned w)
+{
+   inst->Src[i].Register.File  = file;
+   inst->Src[i].Register.Index = index;
+   inst->Src[i].Register.SwizzleX = x;
+   inst->Src[i].Register.SwizzleY = y;
+   inst->Src[i].Register.SwizzleZ = z;
+   inst->Src[i].Register.SwizzleW = w;
+}
+
+#define SET_SRC(inst, i, file, index, x, y, z, w) \
+   set_src(inst, i, file, index, TGSI_SWIZZLE_##x, TGSI_SWIZZLE_##y, \
+           TGSI_SWIZZLE_##z, TGSI_SWIZZLE_##w)
+
+static void
+transform_instr(struct tgsi_transform_context *tctx,
+		struct tgsi_full_instruction *current_inst)
+{
+   struct tgsi_drawpix_transform *ctx = tgsi_drawpix_transform(tctx);
+   struct tgsi_full_declaration decl;
+   struct tgsi_full_instruction inst;
+   unsigned i, semantic;
+   int texcoord_index = -1;
+
+   if (ctx->first_instruction_emitted)
+      goto transform_inst;
+
+   ctx->first_instruction_emitted = true;
+
+   /* Add scale and bias constants. */
+   if (ctx->scale_and_bias) {
+      if (ctx->info.const_file_max[0] < (int)ctx->scale_const) {
+         decl = tgsi_default_full_declaration();
+         decl.Declaration.File = TGSI_FILE_CONSTANT;
+         decl.Range.First = decl.Range.Last = ctx->scale_const;
+         tctx->emit_declaration(tctx, &decl);
+      }
+
+      if (ctx->info.const_file_max[0] < (int)ctx->bias_const) {
+         decl = tgsi_default_full_declaration();
+         decl.Declaration.File = TGSI_FILE_CONSTANT;
+         decl.Range.First = decl.Range.Last = ctx->bias_const;
+         tctx->emit_declaration(tctx, &decl);
+      }
+   }
+
+   /* Add a new temp. */
+   ctx->color_temp = ctx->info.file_max[TGSI_FILE_TEMPORARY] + 1;
+   decl = tgsi_default_full_declaration();
+   decl.Declaration.File = TGSI_FILE_TEMPORARY;
+   decl.Range.First = decl.Range.Last = ctx->color_temp;
+   tctx->emit_declaration(tctx, &decl);
+
+   /* Add TEXCOORD[0] if it's missing. */
+   semantic = ctx->use_texcoord ? TGSI_SEMANTIC_TEXCOORD :
+                                  TGSI_SEMANTIC_GENERIC;
+   for (i = 0; i < ctx->info.num_inputs; i++) {
+      if (ctx->info.input_semantic_name[i] == semantic &&
+          ctx->info.input_semantic_index[i] == 0) {
+         texcoord_index = i;
+         break;
+      }
+   }
+
+   if (texcoord_index == -1) {
+      decl = tgsi_default_full_declaration();
+      decl.Declaration.File = TGSI_FILE_INPUT;
+      decl.Declaration.Semantic = 1;
+      decl.Semantic.Name = semantic;
+      decl.Declaration.Interpolate = 1;
+      decl.Interp.Interpolate = TGSI_INTERPOLATE_PERSPECTIVE;
+      decl.Range.First = decl.Range.Last = ctx->info.num_inputs;
+      texcoord_index = ctx->info.num_inputs;
+      tctx->emit_declaration(tctx, &decl);
+   }
+
+   /* Declare the drawpix sampler if it's missing. */
+   if (ctx->info.file_max[TGSI_FILE_SAMPLER] == -1) {
+      decl = tgsi_default_full_declaration();
+      decl.Declaration.File = TGSI_FILE_SAMPLER;
+      tctx->emit_declaration(tctx, &decl);
+   }
+
+   /* Declare the pixel map sampler if it's missing. */
+   if (ctx->info.file_max[TGSI_FILE_SAMPLER] <= 0) {
+      decl = tgsi_default_full_declaration();
+      decl.Declaration.File = TGSI_FILE_SAMPLER;
+      decl.Range.First = decl.Range.Last = 1;
+      tctx->emit_declaration(tctx, &decl);
+   }
+
+   /* Get initial pixel color from the texture.
+    * TEX temp, fragment.texcoord[0], texture[0], 2D;
+    */
+   inst = tgsi_default_full_instruction();
+   inst.Instruction.Opcode = TGSI_OPCODE_TEX;
+   inst.Instruction.Texture = 1;
+   inst.Texture.Texture = TGSI_TEXTURE_2D;
+
+   inst.Instruction.NumDstRegs = 1;
+   inst.Dst[0].Register.File  = TGSI_FILE_TEMPORARY;
+   inst.Dst[0].Register.Index = ctx->color_temp;
+   inst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_XYZW;
+
+   inst.Instruction.NumSrcRegs = 2;
+   SET_SRC(&inst, 0, TGSI_FILE_INPUT, texcoord_index, X, Y, Z, W);
+   inst.Src[1].Register.File  = TGSI_FILE_SAMPLER;
+   inst.Src[1].Register.Index = 0;
+
+   tctx->emit_instruction(tctx, &inst);
+
+   /* Apply the scale and bias. */
+   if (ctx->scale_and_bias) {
+      /* MAD temp, temp, scale, bias; */
+      inst = tgsi_default_full_instruction();
+      inst.Instruction.Opcode = TGSI_OPCODE_MAD;
+
+      inst.Instruction.NumDstRegs = 1;
+      inst.Dst[0].Register.File  = TGSI_FILE_TEMPORARY;
+      inst.Dst[0].Register.Index = ctx->color_temp;
+      inst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_XYZW;
+
+      inst.Instruction.NumSrcRegs = 3;
+      SET_SRC(&inst, 0, TGSI_FILE_TEMPORARY, ctx->color_temp, X, Y, Z, W);
+      SET_SRC(&inst, 1, TGSI_FILE_CONSTANT, ctx->scale_const, X, Y, Z, W);
+      SET_SRC(&inst, 2, TGSI_FILE_CONSTANT, ctx->bias_const, X, Y, Z, W);
+
+      tctx->emit_instruction(tctx, &inst);
+   }
+
+   if (ctx->pixel_maps) {
+      /* do four pixel map look-ups with two TEX instructions: */
+
+      /* TEX temp.xy, temp.xyyy, texture[1], 2D; */
+      inst = tgsi_default_full_instruction();
+      inst.Instruction.Opcode = TGSI_OPCODE_TEX;
+      inst.Instruction.Texture = 1;
+      inst.Texture.Texture = TGSI_TEXTURE_2D;
+
+      inst.Instruction.NumDstRegs = 1;
+      inst.Dst[0].Register.File  = TGSI_FILE_TEMPORARY;
+      inst.Dst[0].Register.Index = ctx->color_temp;
+      inst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_XY;
+
+      inst.Instruction.NumSrcRegs = 2;
+      SET_SRC(&inst, 0, TGSI_FILE_TEMPORARY, ctx->color_temp, X, Y, Y, Y);
+      inst.Src[1].Register.File  = TGSI_FILE_SAMPLER;
+      inst.Src[1].Register.Index = 1;
+
+      tctx->emit_instruction(tctx, &inst);
+
+      /* TEX temp.zw, temp.zwww, texture[1], 2D; */
+      inst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_ZW;
+      SET_SRC(&inst, 0, TGSI_FILE_TEMPORARY, ctx->color_temp, Z, W, W, W);
+      tctx->emit_instruction(tctx, &inst);
+   }
+
+   /* Now, "color_temp" should be used in place of IN:COLOR0 */
+
+transform_inst:
+
+   for (i = 0; i < current_inst->Instruction.NumSrcRegs; i++) {
+      struct tgsi_full_src_register *src = &current_inst->Src[i];
+      unsigned reg = src->Register.Index;
+
+      if (src->Register.File == TGSI_FILE_INPUT &&
+          !src->Register.Indirect &&
+          ctx->info.input_semantic_name[reg] == TGSI_SEMANTIC_COLOR &&
+          ctx->info.input_semantic_index[reg] == 0) {
+         src->Register.File = TGSI_FILE_TEMPORARY;
+         src->Register.Index = ctx->color_temp;
+      }
+   }
+
+   tctx->emit_instruction(tctx, current_inst);
+}
+
+const struct tgsi_token *
+st_get_drawpix_shader(const struct tgsi_token *tokens, bool use_texcoord,
+                      bool scale_and_bias, unsigned scale_const,
+                      unsigned bias_const, bool pixel_maps)
+{
+   struct tgsi_drawpix_transform ctx;
+   struct tgsi_token *newtoks;
+   int newlen;
+
+   memset(&ctx, 0, sizeof(ctx));
+   ctx.base.transform_instruction = transform_instr;
+   ctx.use_texcoord = use_texcoord;
+   ctx.scale_and_bias = scale_and_bias;
+   ctx.scale_const = scale_const;
+   ctx.bias_const = bias_const;
+   ctx.pixel_maps = pixel_maps;
+   tgsi_scan_shader(tokens, &ctx.info);
+
+   newlen = tgsi_num_tokens(tokens) + 30;
+   newtoks = tgsi_alloc_tokens(newlen);
+   if (!newtoks)
+      return NULL;
+
+   tgsi_transform_shader(tokens, newtoks, newlen, &ctx.base);
+   return newtoks;
+}