gallium: Copy fd_lowering.[ch] to tgsi_lowering.[ch] for code sharing.

Lots of drivers need to transform the weird instructions in TGSI into
reasonable scalar ops, and this code can make those translations
canonical.

Acked-by: Rob Clark <[email protected]>

1 files changed, 89 insertions, 0 deletions

diff --git a/src/gallium/auxiliary/tgsi/tgsi_lowering.h b/src/gallium/auxiliary/tgsi/tgsi_lowering.h
new file mode 100644
index 00000000000..1b0daa96f0e
--- /dev/null
+++ b/src/gallium/auxiliary/tgsi/tgsi_lowering.h
@@ -0,0 +1,89 @@
+/* -*- mode: C; c-file-style: "k&r"; tab-width 4; indent-tabs-mode: t; -*- */
+
+/*
+ * Copyright (C) 2014 Rob Clark <[email protected]>
+ *
+ * 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, sublicense,
+ * 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 NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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.
+ *
+ * Authors:
+ *    Rob Clark <[email protected]>
+ */
+
+#ifndef FREEDRENO_LOWERING_H_
+#define FREEDRENO_LOWERING_H_
+
+#include "pipe/p_shader_tokens.h"
+#include "tgsi/tgsi_scan.h"
+
+struct fd_lowering_config {
+	/* For fragment shaders, generate a shader that emulates two
+	 * sided color by inserting a BGCOLOR input for each COLOR
+	 * input, and insert a CMP instruction to select the correct
+	 * color to use based on the TGSI_SEMANTIC_FACE input.
+	 *
+	 * Note that drivers which use this to emulate two sided color
+	 * will:
+	 *  a) need to generate (on demand) alternate shaders to use
+	 *     depending on the rasterizer state (ie. whether two
+	 *     sided shading enabled)
+	 *  b) expect to see the BGCOLOR semantic name in fragment
+	 *     shaders.  During linkage, the driver should simply
+	 *     map VS.OUT.BGCOLOR[n] to FS.IN.BGCOLOR[n] (in the
+	 *     same was as linking other outs/ins).
+	 */
+	unsigned color_two_side : 1;
+
+	/* TODO support for alpha_to_one as well?? */
+
+	/* Individual OPC lowerings, if lower_<opc> is TRUE then
+	 * enable lowering of TGSI_OPCODE_<opc>
+	 */
+	unsigned lower_DST : 1;
+	unsigned lower_XPD : 1;
+	unsigned lower_SCS : 1;
+	unsigned lower_LRP : 1;
+	unsigned lower_FRC : 1;
+	unsigned lower_POW : 1;
+	unsigned lower_LIT : 1;
+	unsigned lower_EXP : 1;
+	unsigned lower_LOG : 1;
+	unsigned lower_DP4 : 1;
+	unsigned lower_DP3 : 1;
+	unsigned lower_DPH : 1;
+	unsigned lower_DP2 : 1;
+	unsigned lower_DP2A : 1;
+
+	/* To emulate certain texture wrap modes, this can be used
+	 * to saturate the specified tex coord to [0.0, 1.0].  The
+	 * bits are according to sampler #, ie. if, for example:
+	 *
+	 *   (conf->saturate_s & (1 << n))
+	 *
+	 * is true, then the s coord for sampler n is saturated.
+	 */
+	unsigned saturate_s, saturate_t, saturate_r;
+};
+
+const struct tgsi_token * fd_transform_lowering(
+		const struct fd_lowering_config *config,
+		const struct tgsi_token *tokens,
+		struct tgsi_shader_info *info);
+
+#endif /* FREEDRENO_LOWERING_H_ */