panfrost: Move liveness analysis to root panfrost/

This way we can share the code with Bifrost.

Signed-off-by: Alyssa Rosenzweig <[email protected]>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4150>

5 files changed, 249 insertions, 189 deletions

diff --git a/src/panfrost/midgard/compiler.h b/src/panfrost/midgard/compiler.h
index f9b0c8c2198..34a53cd1ac3 100644
--- a/src/panfrost/midgard/compiler.h
+++ b/src/panfrost/midgard/compiler.h
@@ -165,29 +165,6 @@ typedef struct midgard_instruction {
         };
 } midgard_instruction;
 
-typedef struct pan_block {
-        /* Link to next block. Must be first for mir_get_block */
-        struct list_head link;
-
-        /* List of instructions emitted for the current block */
-        struct list_head instructions;
-
-        /* Index of the block in source order */
-        unsigned name;
-
-        /* Control flow graph */
-        struct pan_block *successors[2];
-        unsigned nr_successors;
-
-        struct set *predecessors;
-
-        /* In liveness analysis, these are live masks (per-component) for
-         * indices for the block. Scalar compilers have the luxury of using
-         * simple bit fields, but for us, liveness is a vector idea. */
-        uint16_t *live_in;
-        uint16_t *live_out;
-} pan_block;
-
 typedef struct midgard_block {
         pan_block base;
 
@@ -377,9 +354,6 @@ mir_next_op(struct midgard_instruction *ins)
 #define mir_foreach_instr_in_block_rev(block, v) \
         list_for_each_entry_rev(struct midgard_instruction, v, &block->base.instructions, link)
 
-#define pan_foreach_instr_in_block_rev(block, v) \
-        list_for_each_entry_rev(struct midgard_instruction, v, &block->instructions, link)
-
 #define mir_foreach_instr_in_block_safe(block, v) \
         list_for_each_entry_safe(struct midgard_instruction, v, &block->base.instructions, link)
 
@@ -422,14 +396,6 @@ mir_next_op(struct midgard_instruction *ins)
                 v != NULL && _v < &blk->base.successors[2]; \
                 _v++, v = *_v) \
 
-#define pan_foreach_successor(blk, v) \
-        pan_block *v; \
-        pan_block **_v; \
-        for (_v = (pan_block **) &blk->successors[0], \
-                v = *_v; \
-                v != NULL && _v < (pan_block **) &blk->successors[2]; \
-                _v++, v = *_v) \
-
 /* Based on set_foreach, expanded with automatic type casts */
 
 #define mir_foreach_predecessor(blk, v) \
@@ -441,15 +407,6 @@ mir_next_op(struct midgard_instruction *ins)
                 _entry_##v = _mesa_set_next_entry(blk->base.predecessors, _entry_##v), \
                 v = (struct midgard_block *) (_entry_##v ? _entry_##v->key : NULL))
 
-#define pan_foreach_predecessor(blk, v) \
-        struct set_entry *_entry_##v; \
-        struct pan_block *v; \
-        for (_entry_##v = _mesa_set_next_entry(blk->predecessors, NULL), \
-                v = (struct pan_block *) (_entry_##v ? _entry_##v->key : NULL);  \
-                _entry_##v != NULL; \
-                _entry_##v = _mesa_set_next_entry(blk->predecessors, _entry_##v), \
-                v = (struct pan_block *) (_entry_##v ? _entry_##v->key : NULL))
-
 #define mir_foreach_src(ins, v) \
         for (unsigned v = 0; v < ARRAY_SIZE(ins->src); ++v)
 
@@ -470,19 +427,6 @@ mir_get_block(compiler_context *ctx, int idx)
         return (struct midgard_block *) lst;
 }
 
-static inline midgard_block *
-mir_exit_block(struct compiler_context *ctx)
-{
-        pan_block *last = list_last_entry(&ctx->blocks, pan_block, link);
-
-        /* The last block must be empty logically but contains branch writeout
-         * for fragment shaders */
-
-        assert(last->nr_successors == 0);
-
-        return (midgard_block *) last;
-}
-
 static inline bool
 mir_is_alu_bundle(midgard_bundle *bundle)
 {
diff --git a/src/panfrost/midgard/midgard_liveness.c b/src/panfrost/midgard/midgard_liveness.c
index 9481cded56a..af7fba9939c 100644
--- a/src/panfrost/midgard/midgard_liveness.c
+++ b/src/panfrost/midgard/midgard_liveness.c
@@ -22,99 +22,28 @@
  */
 
 #include "compiler.h"
-#include "util/u_memory.h"
-
-/* Routines for liveness analysis. Liveness is tracked per byte per node. Per
- * byte granularity is necessary for proper handling of int8 */
-
-static void
-liveness_gen(uint16_t *live, unsigned node, unsigned max, uint16_t mask)
-{
-        if (node >= max)
-                return;
-
-        live[node] |= mask;
-}
-
-static void
-liveness_kill(uint16_t *live, unsigned node, unsigned max, uint16_t mask)
-{
-        if (node >= max)
-                return;
-
-        live[node] &= ~mask;
-}
-
-static bool
-liveness_get(uint16_t *live, unsigned node, uint16_t max) {
-        if (node >= max)
-                return false;
-
-        return live[node];
-}
-
-/* Updates live_in for a single instruction */
 
 void
 mir_liveness_ins_update(uint16_t *live, midgard_instruction *ins, unsigned max)
 {
         /* live_in[s] = GEN[s] + (live_out[s] - KILL[s]) */
 
-        liveness_kill(live, ins->dest, max, mir_bytemask(ins));
+        pan_liveness_kill(live, ins->dest, max, mir_bytemask(ins));
 
         mir_foreach_src(ins, src) {
                 unsigned node = ins->src[src];
                 unsigned bytemask = mir_bytemask_of_read_components(ins, node);
 
-                liveness_gen(live, node, max, bytemask);
+                pan_liveness_gen(live, node, max, bytemask);
         }
 }
 
-/* live_out[s] = sum { p in succ[s] } ( live_in[p] ) */
-
 static void
-liveness_block_live_out(pan_block *blk, unsigned temp_count)
+mir_liveness_ins_update_wrap(uint16_t *live, void *ins, unsigned max)
 {
-        pan_foreach_successor(blk, succ) {
-                for (unsigned i = 0; i < temp_count; ++i)
-                        blk->live_out[i] |= succ->live_in[i];
-        }
+        mir_liveness_ins_update(live, (midgard_instruction *) ins, max);
 }
 
-/* Liveness analysis is a backwards-may dataflow analysis pass. Within a block,
- * we compute live_out from live_in. The intrablock pass is linear-time. It
- * returns whether progress was made. */
-
-static bool
-liveness_block_update(pan_block *blk, unsigned temp_count)
-{
-        bool progress = false;
-
-        liveness_block_live_out(blk, temp_count);
-
-        uint16_t *live = ralloc_array(blk, uint16_t, temp_count);
-        memcpy(live, blk->live_out, temp_count * sizeof(uint16_t));
-
-        pan_foreach_instr_in_block_rev(blk, ins)
-                mir_liveness_ins_update(live, ins, temp_count);
-
-        /* To figure out progress, diff live_in */
-
-        for (unsigned i = 0; (i < temp_count) && !progress; ++i)
-                progress |= (blk->live_in[i] != live[i]);
-
-        ralloc_free(blk->live_in);
-        blk->live_in = live;
-
-        return progress;
-}
-
-/* Globally, liveness analysis uses a fixed-point algorithm based on a
- * worklist. We initialize a work list with the exit block. We iterate the work
- * list to compute live_in from live_out for each block on the work list,
- * adding the predecessors of the block to the work list if we made progress.
- */
-
 void
 mir_compute_liveness(compiler_context *ctx)
 {
@@ -123,52 +52,7 @@ mir_compute_liveness(compiler_context *ctx)
                 return;
 
         mir_compute_temp_count(ctx);
-        unsigned temp_count = ctx->temp_count;
-
-        /* List of midgard_block */
-        struct set *work_list = _mesa_set_create(ctx,
-                        _mesa_hash_pointer,
-                        _mesa_key_pointer_equal);
-
-        struct set *visited = _mesa_set_create(ctx,
-                        _mesa_hash_pointer,
-                        _mesa_key_pointer_equal);
-
-        /* Allocate */
-
-        mir_foreach_block(ctx, block) {
-                block->live_in = rzalloc_array(NULL, uint16_t, temp_count);
-                block->live_out = rzalloc_array(NULL, uint16_t, temp_count);
-        }
-
-        /* Initialize the work list with the exit block */
-        struct set_entry *cur;
-
-        midgard_block *exit = mir_exit_block(ctx);
-        cur = _mesa_set_add(work_list, exit);
-
-        /* Iterate the work list */
-
-        do {
-                /* Pop off a block */
-                pan_block *blk = (struct pan_block *) cur->key;
-                _mesa_set_remove(work_list, cur);
-
-                /* Update its liveness information */
-                bool progress = liveness_block_update(blk, temp_count);
-
-                /* If we made progress, we need to process the predecessors */
-
-                if (progress || !_mesa_set_search(visited, blk)) {
-                        pan_foreach_predecessor(blk, pred)
-                                _mesa_set_add(work_list, pred);
-                }
-
-                _mesa_set_add(visited, blk);
-        } while((cur = _mesa_set_next_entry(work_list, NULL)) != NULL);
-
-        _mesa_set_destroy(visited, NULL);
-        _mesa_set_destroy(work_list, NULL);
+        pan_compute_liveness(&ctx->blocks, ctx->temp_count, mir_liveness_ins_update_wrap);
 
         /* Liveness is now valid */
         ctx->metadata |= MIDGARD_METADATA_LIVENESS;
@@ -183,19 +67,10 @@ mir_invalidate_liveness(compiler_context *ctx)
         if (!(ctx->metadata & MIDGARD_METADATA_LIVENESS))
                 return;
 
+        pan_free_liveness(&ctx->blocks);
+
         /* It's now invalid regardless */
         ctx->metadata &= ~MIDGARD_METADATA_LIVENESS;
-
-        mir_foreach_block(ctx, block) {
-                if (block->live_in)
-                        ralloc_free(block->live_in);
-
-                if (block->live_out)
-                        ralloc_free(block->live_out);
-
-                block->live_in = NULL;
-                block->live_out = NULL;
-        }
 }
 
 bool
@@ -205,7 +80,7 @@ mir_is_live_after(compiler_context *ctx, midgard_block *block, midgard_instructi
 
         /* Check whether we're live in the successors */
 
-        if (liveness_get(block->base.live_out, src, ctx->temp_count))
+        if (pan_liveness_get(block->base.live_out, src, ctx->temp_count))
                 return true;
 
         /* Check the rest of the block for liveness */
diff --git a/src/panfrost/util/meson.build b/src/panfrost/util/meson.build
index cf8577041dd..76e2249b60e 100644
--- a/src/panfrost/util/meson.build
+++ b/src/panfrost/util/meson.build
@@ -22,6 +22,7 @@
 libpanfrost_util_files = files(
   'pan_ir.c',
   'pan_ir.h',
+  'pan_liveness.c',
   'pan_sysval.c',
 )
 
diff --git a/src/panfrost/util/pan_ir.h b/src/panfrost/util/pan_ir.h
index 425c5246c1c..6b132228ddd 100644
--- a/src/panfrost/util/pan_ir.h
+++ b/src/panfrost/util/pan_ir.h
@@ -116,6 +116,66 @@ typedef struct {
         float alpha_ref;
 } panfrost_program;
 
+typedef struct pan_block {
+        /* Link to next block. Must be first for mir_get_block */
+        struct list_head link;
+
+        /* List of instructions emitted for the current block */
+        struct list_head instructions;
+
+        /* Index of the block in source order */
+        unsigned name;
+
+        /* Control flow graph */
+        struct pan_block *successors[2];
+        unsigned nr_successors;
+
+        struct set *predecessors;
+
+        /* In liveness analysis, these are live masks (per-component) for
+         * indices for the block. Scalar compilers have the luxury of using
+         * simple bit fields, but for us, liveness is a vector idea. */
+        uint16_t *live_in;
+        uint16_t *live_out;
+} pan_block;
+
+struct pan_instruction {
+        struct list_head link;
+};
+
+#define pan_foreach_instr_in_block_rev(block, v) \
+        list_for_each_entry_rev(struct pan_instruction, v, &block->instructions, link)
+
+#define pan_foreach_successor(blk, v) \
+        pan_block *v; \
+        pan_block **_v; \
+        for (_v = (pan_block **) &blk->successors[0], \
+                v = *_v; \
+                v != NULL && _v < (pan_block **) &blk->successors[2]; \
+                _v++, v = *_v) \
+
+#define pan_foreach_predecessor(blk, v) \
+        struct set_entry *_entry_##v; \
+        struct pan_block *v; \
+        for (_entry_##v = _mesa_set_next_entry(blk->predecessors, NULL), \
+                v = (struct pan_block *) (_entry_##v ? _entry_##v->key : NULL);  \
+                _entry_##v != NULL; \
+                _entry_##v = _mesa_set_next_entry(blk->predecessors, _entry_##v), \
+                v = (struct pan_block *) (_entry_##v ? _entry_##v->key : NULL))
+
+
+typedef void (*pan_liveness_update)(uint16_t *, void *, unsigned max);
+
+void pan_liveness_gen(uint16_t *live, unsigned node, unsigned max, uint16_t mask);
+void pan_liveness_kill(uint16_t *live, unsigned node, unsigned max, uint16_t mask);
+bool pan_liveness_get(uint16_t *live, unsigned node, uint16_t max);
+
+void pan_compute_liveness(struct list_head *blocks,
+                unsigned temp_count,
+                pan_liveness_update callback);
+
+void pan_free_liveness(struct list_head *blocks);
+
 uint16_t
 pan_to_bytemask(unsigned bytes, unsigned mask);
 
diff --git a/src/panfrost/util/pan_liveness.c b/src/panfrost/util/pan_liveness.c
new file mode 100644
index 00000000000..48ec71b253a
--- /dev/null
+++ b/src/panfrost/util/pan_liveness.c
@@ -0,0 +1,180 @@
+/*
+ * Copyright (C) 2019-2020 Collabora, Ltd.
+ *
+ * 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.
+ */
+
+#include "pan_ir.h"
+#include "util/u_memory.h"
+#include "util/list.h"
+#include "util/set.h"
+
+/* Routines for liveness analysis. Liveness is tracked per byte per node. Per
+ * byte granularity is necessary for proper handling of int8 */
+
+void
+pan_liveness_gen(uint16_t *live, unsigned node, unsigned max, uint16_t mask)
+{
+        if (node >= max)
+                return;
+
+        live[node] |= mask;
+}
+
+void
+pan_liveness_kill(uint16_t *live, unsigned node, unsigned max, uint16_t mask)
+{
+        if (node >= max)
+                return;
+
+        live[node] &= ~mask;
+}
+
+bool
+pan_liveness_get(uint16_t *live, unsigned node, uint16_t max)
+{
+        if (node >= max)
+                return false;
+
+        return live[node];
+}
+
+/* live_out[s] = sum { p in succ[s] } ( live_in[p] ) */
+
+static void
+liveness_block_live_out(pan_block *blk, unsigned temp_count)
+{
+        pan_foreach_successor(blk, succ) {
+                for (unsigned i = 0; i < temp_count; ++i)
+                        blk->live_out[i] |= succ->live_in[i];
+        }
+}
+
+/* Liveness analysis is a backwards-may dataflow analysis pass. Within a block,
+ * we compute live_out from live_in. The intrablock pass is linear-time. It
+ * returns whether progress was made. */
+
+static bool
+liveness_block_update(
+                pan_block *blk, unsigned temp_count,
+                pan_liveness_update callback)
+{
+        bool progress = false;
+
+        liveness_block_live_out(blk, temp_count);
+
+        uint16_t *live = ralloc_array(blk, uint16_t, temp_count);
+        memcpy(live, blk->live_out, temp_count * sizeof(uint16_t));
+
+        pan_foreach_instr_in_block_rev(blk, ins)
+                callback(live, (void *) ins, temp_count);
+
+        /* To figure out progress, diff live_in */
+
+        for (unsigned i = 0; (i < temp_count) && !progress; ++i)
+                progress |= (blk->live_in[i] != live[i]);
+
+        ralloc_free(blk->live_in);
+        blk->live_in = live;
+
+        return progress;
+}
+
+
+/* Globally, liveness analysis uses a fixed-point algorithm based on a
+ * worklist. We initialize a work list with the exit block. We iterate the work
+ * list to compute live_in from live_out for each block on the work list,
+ * adding the predecessors of the block to the work list if we made progress.
+ */
+
+static inline pan_block *
+pan_exit_block(struct list_head *blocks)
+{
+        pan_block *last = list_last_entry(blocks, pan_block, link);
+        assert(last->nr_successors == 0);
+        return last;
+}
+
+void
+pan_compute_liveness(
+                struct list_head *blocks,
+                unsigned temp_count,
+                pan_liveness_update callback)
+{
+
+        /* Set of pan_block */
+        struct set *work_list = _mesa_set_create(NULL,
+                        _mesa_hash_pointer,
+                        _mesa_key_pointer_equal);
+
+        struct set *visited = _mesa_set_create(NULL,
+                        _mesa_hash_pointer,
+                        _mesa_key_pointer_equal);
+
+        /* Allocate */
+
+        list_for_each_entry(pan_block, block, blocks, link) {
+                block->live_in = rzalloc_array(NULL, uint16_t, temp_count);
+                block->live_out = rzalloc_array(NULL, uint16_t, temp_count);
+        }
+
+        /* Initialize the work list with the exit block */
+        struct set_entry *cur;
+
+        cur = _mesa_set_add(work_list, pan_exit_block(blocks));
+
+        /* Iterate the work list */
+
+        do {
+                /* Pop off a block */
+                pan_block *blk = (struct pan_block *) cur->key;
+                _mesa_set_remove(work_list, cur);
+
+                /* Update its liveness information */
+                bool progress = liveness_block_update(blk, temp_count, callback);
+
+                /* If we made progress, we need to process the predecessors */
+
+                if (progress || !_mesa_set_search(visited, blk)) {
+                        pan_foreach_predecessor(blk, pred)
+                                _mesa_set_add(work_list, pred);
+                }
+
+                _mesa_set_add(visited, blk);
+        } while((cur = _mesa_set_next_entry(work_list, NULL)) != NULL);
+
+        _mesa_set_destroy(visited, NULL);
+        _mesa_set_destroy(work_list, NULL);
+}
+
+void
+pan_free_liveness(struct list_head *blocks)
+{
+        list_for_each_entry(pan_block, block, blocks, link) {
+                if (block->live_in)
+                        ralloc_free(block->live_in);
+
+                if (block->live_out)
+                        ralloc_free(block->live_out);
+
+                block->live_in = NULL;
+                block->live_out = NULL;
+        }
+}