X-Git-Url: https://git.libre-soc.org/?a=blobdiff_plain;f=src%2Fgallium%2Fdrivers%2Fvc4%2Fvc4_opt_copy_propagation.c;h=d20ee5e227d5f4195db3c0eba9079918e1eb57c5;hb=8810270d066eced5261ab407e2be4e902b102671;hp=a755de9aa418c03181cadcd61155f64585eaff80;hpb=6a7ca4ef2cd3f39d3b5e77051cb3f3175e9e60df;p=mesa.git

diff --git a/src/gallium/drivers/vc4/vc4_opt_copy_propagation.c b/src/gallium/drivers/vc4/vc4_opt_copy_propagation.c
index a755de9aa41..d20ee5e227d 100644
--- a/src/gallium/drivers/vc4/vc4_opt_copy_propagation.c
+++ b/src/gallium/drivers/vc4/vc4_opt_copy_propagation.c
@@ -34,44 +34,168 @@
 
 #include "vc4_qir.h"
 
-bool
-qir_opt_copy_propagation(struct vc4_compile *c)
+static bool
+is_copy_mov(struct qinst *inst)
+{
+        if (!inst)
+                return false;
+
+        if (inst->op != QOP_MOV &&
+            inst->op != QOP_FMOV &&
+            inst->op != QOP_MMOV) {
+                return false;
+        }
+
+        if (inst->dst.file != QFILE_TEMP)
+                return false;
+
+        if (inst->src[0].file != QFILE_TEMP &&
+            inst->src[0].file != QFILE_UNIF) {
+                return false;
+        }
+
+        if (inst->dst.pack || inst->cond != QPU_COND_ALWAYS)
+                return false;
+
+        return true;
+
+}
+
+static bool
+try_copy_prop(struct vc4_compile *c, struct qinst *inst, struct qinst **movs)
 {
-        bool progress = false;
         bool debug = false;
-        struct qreg *movs = calloc(c->num_temps, sizeof(struct qreg));
-
-        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 &&
-                            (movs[index].file == QFILE_TEMP ||
-                             movs[index].file == QFILE_UNIF)) {
-                                if (debug) {
-                                        fprintf(stderr, "Copy propagate: ");
-                                        qir_dump_inst(c, inst);
-                                        fprintf(stderr, "\n");
-                                }
-
-                                inst->src[i] = movs[index];
-
-                                if (debug) {
-                                        fprintf(stderr, "to: ");
-                                        qir_dump_inst(c, inst);
-                                        fprintf(stderr, "\n");
-                                }
-
-                                progress = true;
+        bool progress = false;
+
+	for (int i = 0; i < qir_get_op_nsrc(inst->op); i++) {
+                if (inst->src[i].file != QFILE_TEMP)
+                        continue;
+
+                /* We have two ways of finding MOVs we can copy propagate
+                 * from.  One is if it's an SSA def: then we can reuse it from
+                 * any block in the program, as long as its source is also an
+                 * SSA def.  Alternatively, if it's in the "movs" array
+                 * tracked within the block, then we know the sources for it
+                 * haven't been changed since we saw the instruction within
+                 * our block.
+                 */
+                struct qinst *mov = movs[inst->src[i].index];
+                if (!mov) {
+                        if (!is_copy_mov(c->defs[inst->src[i].index]))
+                                continue;
+                        mov = c->defs[inst->src[i].index];
+
+                        if (mov->src[0].file == QFILE_TEMP &&
+                            !c->defs[mov->src[0].index])
+                                continue;
+                }
+
+                /* Mul rotation's source needs to be in an r0-r3 accumulator,
+                 * so no uniforms or regfile-a/r4 unpacking allowed.
+                 */
+                if (inst->op == QOP_ROT_MUL &&
+                    (mov->src[0].file != QFILE_TEMP ||
+                     mov->src[0].pack))
+                        continue;
+
+                uint8_t unpack;
+                if (mov->src[0].pack) {
+                        /* Make sure that the meaning of the unpack
+                         * would be the same between the two
+                         * instructions.
+                         */
+                        if (qir_is_float_input(inst) !=
+                            qir_is_float_input(mov)) {
+                                continue;
+                        }
+
+                        /* There's only one unpack field, so make sure
+                         * this instruction doesn't already use it.
+                         */
+                        bool already_has_unpack = false;
+                        for (int j = 0; j < qir_get_op_nsrc(inst->op); j++) {
+                                if (inst->src[j].pack)
+                                        already_has_unpack = true;
                         }
+                        if (already_has_unpack)
+                                continue;
+
+                        /* A destination pack requires the PM bit to
+                         * be set to a specific value already, which
+                         * may be different from ours.
+                         */
+                        if (inst->dst.pack)
+                                continue;
+
+                        unpack = mov->src[0].pack;
+                } else {
+                        unpack = inst->src[i].pack;
                 }
 
-                if (inst->op == QOP_MOV &&
-                    inst->dst.file == QFILE_TEMP &&
-                    inst->src[0].file != QFILE_VPM) {
-                        movs[inst->dst.index] = inst->src[0];
+                if (debug) {
+                        fprintf(stderr, "Copy propagate: ");
+                        qir_dump_inst(c, inst);
+                        fprintf(stderr, "\n");
                 }
+
+                inst->src[i] = mov->src[0];
+                inst->src[i].pack = unpack;
+
+                if (debug) {
+                        fprintf(stderr, "to: ");
+                        qir_dump_inst(c, inst);
+                        fprintf(stderr, "\n");
+                }
+
+                progress = true;
         }
 
-        free(movs);
+        return progress;
+}
+
+static void
+apply_kills(struct vc4_compile *c, struct qinst **movs, struct qinst *inst)
+{
+        if (inst->dst.file != QFILE_TEMP)
+                return;
+
+        for (int i = 0; i < c->num_temps; i++) {
+                if (movs[i] &&
+                    (movs[i]->dst.index == inst->dst.index ||
+                     (movs[i]->src[0].file == QFILE_TEMP &&
+                      movs[i]->src[0].index == inst->dst.index))) {
+                        movs[i] = NULL;
+                }
+        }
+}
+
+bool
+qir_opt_copy_propagation(struct vc4_compile *c)
+{
+        bool progress = false;
+        struct qinst **movs;
+
+        movs = ralloc_array(c, struct qinst *, c->num_temps);
+        if (!movs)
+                return false;
+
+        qir_for_each_block(block, c) {
+                /* The MOVs array tracks only available movs within the
+                 * block.
+                 */
+                memset(movs, 0, sizeof(struct qinst *) * c->num_temps);
+
+                qir_for_each_inst(inst, block) {
+                        progress = try_copy_prop(c, inst, movs) || progress;
+
+                        apply_kills(c, movs, inst);
+
+                        if (is_copy_mov(inst))
+                                movs[inst->dst.index] = inst;
+                }
+        }
+
+        ralloc_free(movs);
+
         return progress;
 }