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-rw-r--r--src/gallium/drivers/llvmpipe/lp_bld_interp.c388
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diff --git a/src/gallium/drivers/llvmpipe/lp_bld_interp.c b/src/gallium/drivers/llvmpipe/lp_bld_interp.c
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+++ b/src/gallium/drivers/llvmpipe/lp_bld_interp.c
@@ -0,0 +1,388 @@
+/**************************************************************************
+ *
+ * Copyright 2009 VMware, Inc.
+ * Copyright 2007-2008 Tungsten Graphics, Inc., Cedar Park, Texas.
+ * 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 TUNGSTEN GRAPHICS 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.
+ *
+ **************************************************************************/
+
+/**
+ * @file
+ * Position and shader input interpolation.
+ *
+ * @author Jose Fonseca <jfonseca@vmware.com>
+ */
+
+#include "pipe/p_shader_tokens.h"
+#include "util/u_debug.h"
+#include "util/u_memory.h"
+#include "util/u_math.h"
+#include "tgsi/tgsi_scan.h"
+#include "gallivm/lp_bld_debug.h"
+#include "gallivm/lp_bld_const.h"
+#include "gallivm/lp_bld_arit.h"
+#include "gallivm/lp_bld_swizzle.h"
+#include "lp_bld_interp.h"
+
+
+/*
+ * The shader JIT function operates on blocks of quads.
+ * Each block has 2x2 quads and each quad has 2x2 pixels.
+ *
+ * We iterate over the quads in order 0, 1, 2, 3:
+ *
+ * #################
+ * # | # | #
+ * #---0---#---1---#
+ * # | # | #
+ * #################
+ * # | # | #
+ * #---2---#---3---#
+ * # | # | #
+ * #################
+ *
+ * Within each quad, we have four pixels which are represented in SOA
+ * order:
+ *
+ * #########
+ * # 0 | 1 #
+ * #---+---#
+ * # 2 | 3 #
+ * #########
+ *
+ * So the green channel (for example) of the four pixels is stored in
+ * a single vector register: {g0, g1, g2, g3}.
+ */
+
+
+static const unsigned char quad_offset_x[4] = {0, 1, 0, 1};
+static const unsigned char quad_offset_y[4] = {0, 0, 1, 1};
+
+
+static void
+attrib_name(LLVMValueRef val, unsigned attrib, unsigned chan, const char *suffix)
+{
+ if(attrib == 0)
+ lp_build_name(val, "pos.%c%s", "xyzw"[chan], suffix);
+ else
+ lp_build_name(val, "input%u.%c%s", attrib - 1, "xyzw"[chan], suffix);
+}
+
+
+/**
+ * Initialize the bld->a0, dadx, dady fields. This involves fetching
+ * those values from the arrays which are passed into the JIT function.
+ */
+static void
+coeffs_init(struct lp_build_interp_soa_context *bld,
+ LLVMValueRef a0_ptr,
+ LLVMValueRef dadx_ptr,
+ LLVMValueRef dady_ptr)
+{
+ struct lp_build_context *coeff_bld = &bld->coeff_bld;
+ LLVMBuilderRef builder = coeff_bld->builder;
+ LLVMValueRef zero = LLVMConstNull(coeff_bld->elem_type);
+ LLVMValueRef one = LLVMConstReal(coeff_bld->elem_type, 1.0);
+ LLVMValueRef i0 = LLVMConstInt(LLVMInt32Type(), 0, 0);
+ LLVMValueRef i1 = LLVMConstInt(LLVMInt32Type(), 1, 0);
+ LLVMValueRef i2 = LLVMConstInt(LLVMInt32Type(), 2, 0);
+ LLVMValueRef i3 = LLVMConstInt(LLVMInt32Type(), 3, 0);
+ LLVMValueRef oow = NULL;
+ unsigned attrib;
+ unsigned chan;
+
+ /* TODO: Use more vector operations */
+
+ for (attrib = 0; attrib < bld->num_attribs; ++attrib) {
+ const unsigned mask = bld->mask[attrib];
+ const unsigned interp = bld->interp[attrib];
+ for (chan = 0; chan < NUM_CHANNELS; ++chan) {
+ if (mask & (1 << chan)) {
+ LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), attrib*NUM_CHANNELS + chan, 0);
+ LLVMValueRef a0 = zero;
+ LLVMValueRef dadx = zero;
+ LLVMValueRef dady = zero;
+ LLVMValueRef dadxy = zero;
+ LLVMValueRef dadq;
+ LLVMValueRef dadq2;
+ LLVMValueRef a;
+
+ switch (interp) {
+ case LP_INTERP_PERSPECTIVE:
+ /* fall-through */
+
+ case LP_INTERP_LINEAR:
+ if (attrib == 0 && chan == 0) {
+ dadxy = dadx = one;
+ }
+ else if (attrib == 0 && chan == 1) {
+ dadxy = dady = one;
+ }
+ else {
+ dadx = LLVMBuildLoad(builder, LLVMBuildGEP(builder, dadx_ptr, &index, 1, ""), "");
+ dady = LLVMBuildLoad(builder, LLVMBuildGEP(builder, dady_ptr, &index, 1, ""), "");
+ dadxy = LLVMBuildAdd(builder, dadx, dady, "");
+ attrib_name(dadx, attrib, chan, ".dadx");
+ attrib_name(dady, attrib, chan, ".dady");
+ attrib_name(dadxy, attrib, chan, ".dadxy");
+ }
+ /* fall-through */
+
+ case LP_INTERP_CONSTANT:
+ case LP_INTERP_FACING:
+ a0 = LLVMBuildLoad(builder, LLVMBuildGEP(builder, a0_ptr, &index, 1, ""), "");
+ attrib_name(a0, attrib, chan, ".a0");
+ break;
+
+ case LP_INTERP_POSITION:
+ /* Nothing to do as the position coeffs are already setup in slot 0 */
+ continue;
+
+ default:
+ assert(0);
+ break;
+ }
+
+ /*
+ * dadq = {0, dadx, dady, dadx + dady}
+ */
+
+ dadq = coeff_bld->undef;
+ dadq = LLVMBuildInsertElement(builder, dadq, zero, i0, "");
+ dadq = LLVMBuildInsertElement(builder, dadq, dadx, i1, "");
+ dadq = LLVMBuildInsertElement(builder, dadq, dady, i2, "");
+ dadq = LLVMBuildInsertElement(builder, dadq, dadxy, i3, "");
+
+ /*
+ * dadq2 = 2 * dq
+ */
+
+ dadq2 = LLVMBuildAdd(builder, dadq, dadq, "");
+
+ /*
+ * a = a0 + x * dadx + y * dady
+ */
+
+ if (attrib == 0 && chan == 0) {
+ a = bld->x;
+ }
+ else if (attrib == 0 && chan == 1) {
+ a = bld->y;
+ }
+ else {
+ a = a0;
+ if (interp != LP_INTERP_CONSTANT &&
+ interp != LP_INTERP_FACING) {
+ a = LLVMBuildAdd(builder, a,
+ LLVMBuildMul(builder, bld->x, dadx, ""),
+ "");
+ a = LLVMBuildAdd(builder, a,
+ LLVMBuildMul(builder, bld->y, dady, ""),
+ "");
+ }
+ }
+
+ /*
+ * a = {a, a, a, a}
+ */
+
+ a = lp_build_broadcast(builder, coeff_bld->vec_type, a);
+
+ /*
+ * Compute the attrib values on the upper-left corner of each quad.
+ */
+
+ a = LLVMBuildAdd(builder, a, dadq2, "");
+
+ /*
+ * a *= 1 / w
+ * dadq *= 1 / w
+ */
+
+ if (interp == LP_INTERP_PERSPECTIVE) {
+ LLVMValueRef w = bld->a[0][3];
+ assert(attrib != 0);
+ assert(bld->mask[0] & TGSI_WRITEMASK_W);
+ if (!oow) {
+ oow = lp_build_rcp(coeff_bld, w);
+ lp_build_name(oow, "oow");
+ }
+ a = lp_build_mul(coeff_bld, a, oow);
+ dadq = lp_build_mul(coeff_bld, dadq, oow);
+ }
+
+ attrib_name(a, attrib, chan, ".a");
+ attrib_name(dadq, attrib, chan, ".dadq");
+
+ bld->a [attrib][chan] = a;
+ bld->dadq[attrib][chan] = dadq;
+ }
+ }
+ }
+}
+
+
+/**
+ * Increment the shader input attribute values.
+ * This is called when we move from one quad to the next.
+ */
+static void
+attribs_update(struct lp_build_interp_soa_context *bld, int quad_index)
+{
+ struct lp_build_context *coeff_bld = &bld->coeff_bld;
+ LLVMValueRef shuffle = lp_build_const_int_vec(coeff_bld->type, quad_index);
+ unsigned attrib;
+ unsigned chan;
+
+ assert(quad_index < 4);
+
+ for(attrib = 0; attrib < bld->num_attribs; ++attrib) {
+ const unsigned mask = bld->mask[attrib];
+ const unsigned interp = bld->interp[attrib];
+ for(chan = 0; chan < NUM_CHANNELS; ++chan) {
+ if(mask & (1 << chan)) {
+ LLVMValueRef a = coeff_bld->undef;
+ if (interp == LP_INTERP_CONSTANT ||
+ interp == LP_INTERP_FACING) {
+ a = bld->a[attrib][chan];
+ }
+ else if (interp == LP_INTERP_POSITION) {
+ assert(attrib > 0);
+ a = bld->attribs[0][chan];
+ }
+ else {
+ a = bld->a[attrib][chan];
+
+ /*
+ * Broadcast the attribute value for this quad into all elements
+ */
+
+ a = LLVMBuildShuffleVector(coeff_bld->builder,
+ a, coeff_bld->undef, shuffle, "");
+
+ /*
+ * Add the derivatives
+ */
+
+ a = lp_build_add(coeff_bld, a, bld->dadq[attrib][chan]);
+
+ attrib_name(a, attrib, chan, "");
+ }
+ bld->attribs[attrib][chan] = a;
+ }
+ }
+ }
+}
+
+
+/**
+ * Generate the position vectors.
+ *
+ * Parameter x0, y0 are the integer values with upper left coordinates.
+ */
+static void
+pos_init(struct lp_build_interp_soa_context *bld,
+ LLVMValueRef x0,
+ LLVMValueRef y0)
+{
+ struct lp_build_context *coeff_bld = &bld->coeff_bld;
+
+ bld->x = LLVMBuildSIToFP(coeff_bld->builder, x0, coeff_bld->elem_type, "");
+ bld->y = LLVMBuildSIToFP(coeff_bld->builder, y0, coeff_bld->elem_type, "");
+}
+
+
+/**
+ * Initialize fragment shader input attribute info.
+ */
+void
+lp_build_interp_soa_init(struct lp_build_interp_soa_context *bld,
+ unsigned num_inputs,
+ const struct lp_shader_input *inputs,
+ LLVMBuilderRef builder,
+ struct lp_type type,
+ LLVMValueRef a0_ptr,
+ LLVMValueRef dadx_ptr,
+ LLVMValueRef dady_ptr,
+ LLVMValueRef x0,
+ LLVMValueRef y0)
+{
+ struct lp_type coeff_type;
+ unsigned attrib;
+ unsigned chan;
+
+ memset(bld, 0, sizeof *bld);
+
+ memset(&coeff_type, 0, sizeof coeff_type);
+ coeff_type.floating = TRUE;
+ coeff_type.sign = TRUE;
+ coeff_type.width = 32;
+ coeff_type.length = QUAD_SIZE;
+
+ /* XXX: we don't support interpolating into any other types */
+ assert(memcmp(&coeff_type, &type, sizeof coeff_type) == 0);
+
+ lp_build_context_init(&bld->coeff_bld, builder, coeff_type);
+
+ /* For convenience */
+ bld->pos = bld->attribs[0];
+ bld->inputs = (const LLVMValueRef (*)[NUM_CHANNELS]) bld->attribs[1];
+
+ /* Position */
+ bld->num_attribs = 1;
+ bld->mask[0] = TGSI_WRITEMASK_XYZW;
+ bld->interp[0] = LP_INTERP_LINEAR;
+
+ /* Inputs */
+ for (attrib = 0; attrib < num_inputs; ++attrib) {
+ bld->mask[1 + attrib] = inputs[attrib].usage_mask;
+ bld->interp[1 + attrib] = inputs[attrib].interp;
+ }
+ bld->num_attribs = 1 + num_inputs;
+
+ /* Ensure all masked out input channels have a valid value */
+ for (attrib = 0; attrib < bld->num_attribs; ++attrib) {
+ for (chan = 0; chan < NUM_CHANNELS; ++chan) {
+ bld->attribs[attrib][chan] = bld->coeff_bld.undef;
+ }
+ }
+
+ pos_init(bld, x0, y0);
+
+ coeffs_init(bld, a0_ptr, dadx_ptr, dady_ptr);
+
+ attribs_update(bld, 0);
+}
+
+
+/**
+ * Advance the position and inputs to the given quad within the block.
+ */
+void
+lp_build_interp_soa_update(struct lp_build_interp_soa_context *bld,
+ int quad_index)
+{
+ assert(quad_index < 4);
+
+ attribs_update(bld, quad_index);
+}
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