import Mesa 11.0.6

1 files changed, 75 insertions, 0 deletions

diff --git a/lib/mesa/src/gallium/drivers/vc4/vc4_opt_copy_propagation.c b/lib/mesa/src/gallium/drivers/vc4/vc4_opt_copy_propagation.c
new file mode 100644
index 000000000..fd2539aed
--- /dev/null
+++ b/lib/mesa/src/gallium/drivers/vc4/vc4_opt_copy_propagation.c
@@ -0,0 +1,75 @@
+/*
+ * Copyright © 2014 Broadcom
+ *
+ * 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.
+ */
+
+/**
+ * @file vc4_opt_copy_propagation.c
+ *
+ * This implements simple copy propagation for QIR without control flow.
+ *
+ * For each temp, it keeps a qreg of which source it was MOVed from, if it
+ * was.  If we see that used later, we can just reuse the source value, since
+ * we know we don't have control flow, and we have SSA for our values so
+ * there's no killing to worry about.
+ */
+
+#include "vc4_qir.h"
+
+bool
+qir_opt_copy_propagation(struct vc4_compile *c)
+{
+        bool progress = false;
+        bool debug = false;
+
+        list_for_each_entry(struct qinst, inst, &c->instructions, link) {
+                for (int i = 0; i < qir_get_op_nsrc(inst->op); i++) {
+                        int index = inst->src[i].index;
+                        if (inst->src[i].file == QFILE_TEMP &&
+                            c->defs[index] &&
+                            c->defs[index]->op == QOP_MOV &&
+                            (c->defs[index]->src[0].file == QFILE_TEMP ||
+                             c->defs[index]->src[0].file == QFILE_UNIF)) {
+                                /* If it has a pack, it shouldn't be an SSA
+                                 * def.
+                                 */
+                                assert(!c->defs[index]->dst.pack);
+
+                                if (debug) {
+                                        fprintf(stderr, "Copy propagate: ");
+                                        qir_dump_inst(c, inst);
+                                        fprintf(stderr, "\n");
+                                }
+
+                                inst->src[i] = c->defs[index]->src[0];
+
+                                if (debug) {
+                                        fprintf(stderr, "to: ");
+                                        qir_dump_inst(c, inst);
+                                        fprintf(stderr, "\n");
+                                }
+
+                                progress = true;
+                        }
+                }
+        }
+        return progress;
+}