i965/fs: Add support for translating ir_triop_fma into MAD.
[mesa.git] / src / mesa / drivers / dri / i965 / brw_schedule_instructions.cpp
index af8af1dc6c1b20ec526110a2ecd718eba84d4c4c..5530683df84f1dd8cf79e34fa98bdfd984952eb0 100644 (file)
  */
 
 #include "brw_fs.h"
+#include "brw_vec4.h"
 #include "glsl/glsl_types.h"
 #include "glsl/ir_optimization.h"
-#include "glsl/ir_print_visitor.h"
+
+using namespace brw;
 
 /** @file brw_fs_schedule_instructions.cpp
  *
@@ -57,7 +59,7 @@ static bool debug = false;
 class schedule_node : public exec_node
 {
 public:
-   schedule_node(fs_inst *inst, const struct intel_context *intel)
+   schedule_node(backend_instruction *inst, const struct brw_context *brw)
    {
       this->inst = inst;
       this->child_array_size = 0;
@@ -70,8 +72,8 @@ public:
       /* We can't measure Gen6 timings directly but expect them to be much
        * closer to Gen7 than Gen4.
        */
-      if (intel->gen >= 6)
-         set_latency_gen7(intel->is_haswell);
+      if (brw->gen >= 6)
+         set_latency_gen7(brw->is_haswell);
       else
          set_latency_gen4();
    }
@@ -79,7 +81,7 @@ public:
    void set_latency_gen4();
    void set_latency_gen7(bool is_haswell);
 
-   fs_inst *inst;
+   backend_instruction *inst;
    schedule_node **children;
    int *child_latency;
    int child_count;
@@ -297,6 +299,7 @@ schedule_node::set_latency_gen7(bool is_haswell)
 
    case FS_OPCODE_VARYING_PULL_CONSTANT_LOAD:
    case FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD:
+   case VS_OPCODE_PULL_CONSTANT_LOAD:
       /* testing using varying-index pull constants:
        *
        * 16 cycles:
@@ -341,15 +344,15 @@ schedule_node::set_latency_gen7(bool is_haswell)
 
 class instruction_scheduler {
 public:
-   instruction_scheduler(fs_visitor *v, void *mem_ctx, int grf_count,
-                         bool post_reg_alloc)
+   instruction_scheduler(backend_visitor *v, int grf_count, bool post_reg_alloc)
    {
-      this->v = v;
-      this->mem_ctx = ralloc_context(mem_ctx);
+      this->bv = v;
+      this->mem_ctx = ralloc_context(v->mem_ctx);
       this->grf_count = grf_count;
       this->instructions.make_empty();
       this->instructions_to_schedule = 0;
       this->post_reg_alloc = post_reg_alloc;
+      this->time = 0;
    }
 
    ~instruction_scheduler()
@@ -360,11 +363,10 @@ public:
    void add_dep(schedule_node *before, schedule_node *after, int latency);
    void add_dep(schedule_node *before, schedule_node *after);
 
-   void add_inst(fs_inst *inst);
-   void calculate_deps();
-   void schedule_instructions(fs_inst *next_block_header);
-
-   schedule_node *choose_instruction_to_schedule();
+   void run(exec_list *instructions);
+   void add_inst(backend_instruction *inst);
+   virtual void calculate_deps() = 0;
+   virtual schedule_node *choose_instruction_to_schedule() = 0;
 
    /**
     * Returns how many cycles it takes the instruction to issue.
@@ -373,23 +375,60 @@ public:
     * with 1 cycle per vector dispatched.  Thus 8-wide pixel shaders take 2
     * cycles to dispatch and 16-wide (compressed) instructions take 4.
     */
-   int issue_time(fs_inst *inst);
+   virtual int issue_time(backend_instruction *inst) = 0;
 
-   bool is_compressed(fs_inst *inst);
+   void schedule_instructions(backend_instruction *next_block_header);
 
    void *mem_ctx;
 
    bool post_reg_alloc;
    int instructions_to_schedule;
    int grf_count;
+   int time;
    exec_list instructions;
+   backend_visitor *bv;
+};
+
+class fs_instruction_scheduler : public instruction_scheduler
+{
+public:
+   fs_instruction_scheduler(fs_visitor *v, int grf_count, bool post_reg_alloc);
+   void calculate_deps();
+   bool is_compressed(fs_inst *inst);
+   schedule_node *choose_instruction_to_schedule();
+   int issue_time(backend_instruction *inst);
    fs_visitor *v;
 };
 
+fs_instruction_scheduler::fs_instruction_scheduler(fs_visitor *v,
+                                                   int grf_count,
+                                                   bool post_reg_alloc)
+   : instruction_scheduler(v, grf_count, post_reg_alloc),
+     v(v)
+{
+}
+
+class vec4_instruction_scheduler : public instruction_scheduler
+{
+public:
+   vec4_instruction_scheduler(vec4_visitor *v, int grf_count);
+   void calculate_deps();
+   schedule_node *choose_instruction_to_schedule();
+   int issue_time(backend_instruction *inst);
+   vec4_visitor *v;
+};
+
+vec4_instruction_scheduler::vec4_instruction_scheduler(vec4_visitor *v,
+                                                       int grf_count)
+   : instruction_scheduler(v, grf_count, true),
+     v(v)
+{
+}
+
 void
-instruction_scheduler::add_inst(fs_inst *inst)
+instruction_scheduler::add_inst(backend_instruction *inst)
 {
-   schedule_node *n = new(mem_ctx) schedule_node(inst, v->intel);
+   schedule_node *n = new(mem_ctx) schedule_node(inst, bv->brw);
 
    assert(!inst->is_head_sentinel());
    assert(!inst->is_tail_sentinel());
@@ -480,7 +519,7 @@ instruction_scheduler::add_barrier_deps(schedule_node *n)
  * actually writes 2 MRFs.
  */
 bool
-instruction_scheduler::is_compressed(fs_inst *inst)
+fs_instruction_scheduler::is_compressed(fs_inst *inst)
 {
    return (v->dispatch_width == 16 &&
           !inst->force_uncompressed &&
@@ -488,7 +527,7 @@ instruction_scheduler::is_compressed(fs_inst *inst)
 }
 
 void
-instruction_scheduler::calculate_deps()
+fs_instruction_scheduler::calculate_deps()
 {
    /* Pre-register-allocation, this tracks the last write per VGRF (so
     * different reg_offsets within it can interfere when they shouldn't).
@@ -521,7 +560,7 @@ instruction_scheduler::calculate_deps()
    /* top-to-bottom dependencies: RAW and WAW. */
    foreach_list(node, &instructions) {
       schedule_node *n = (schedule_node *)node;
-      fs_inst *inst = n->inst;
+      fs_inst *inst = (fs_inst *)n->inst;
 
       if (inst->opcode == FS_OPCODE_PLACEHOLDER_HALT)
          add_barrier_deps(n);
@@ -539,7 +578,10 @@ instruction_scheduler::calculate_deps()
                    (inst->src[i].fixed_hw_reg.file ==
                     BRW_GENERAL_REGISTER_FILE)) {
            if (post_reg_alloc) {
-               for (int r = 0; r < reg_width; r++)
+               int size = reg_width;
+               if (inst->src[i].fixed_hw_reg.vstride == BRW_VERTICAL_STRIDE_0)
+                  size = 1;
+               for (int r = 0; r < size; r++)
                   add_dep(last_grf_write[inst->src[i].fixed_hw_reg.nr + r], n);
             } else {
                add_dep(last_fixed_grf_write, n);
@@ -629,7 +671,7 @@ instruction_scheduler::calculate_deps()
        !node->is_head_sentinel();
        node = prev, prev = node->prev) {
       schedule_node *n = (schedule_node *)node;
-      fs_inst *inst = n->inst;
+      fs_inst *inst = (fs_inst *)n->inst;
 
       /* write-after-read deps. */
       for (int i = 0; i < 3; i++) {
@@ -644,7 +686,10 @@ instruction_scheduler::calculate_deps()
                    (inst->src[i].fixed_hw_reg.file ==
                     BRW_GENERAL_REGISTER_FILE)) {
            if (post_reg_alloc) {
-               for (int r = 0; r < reg_width; r++)
+               int size = reg_width;
+               if (inst->src[i].fixed_hw_reg.vstride == BRW_VERTICAL_STRIDE_0)
+                  size = 1;
+               for (int r = 0; r < size; r++)
                   add_dep(n, last_grf_write[inst->src[i].fixed_hw_reg.nr + r]);
             } else {
                add_dep(n, last_fixed_grf_write);
@@ -720,8 +765,165 @@ instruction_scheduler::calculate_deps()
    }
 }
 
+void
+vec4_instruction_scheduler::calculate_deps()
+{
+   schedule_node *last_grf_write[grf_count];
+   schedule_node *last_mrf_write[BRW_MAX_MRF];
+   schedule_node *last_conditional_mod = NULL;
+   /* Fixed HW registers are assumed to be separate from the virtual
+    * GRFs, so they can be tracked separately.  We don't really write
+    * to fixed GRFs much, so don't bother tracking them on a more
+    * granular level.
+    */
+   schedule_node *last_fixed_grf_write = NULL;
+
+   /* The last instruction always needs to still be the last instruction.
+    * Either it's flow control (IF, ELSE, ENDIF, DO, WHILE) and scheduling
+    * other things after it would disturb the basic block, or it's the EOT
+    * URB_WRITE and we should do a better job at dead code eliminating
+    * anything that could have been scheduled after it.
+    */
+   schedule_node *last = (schedule_node *)instructions.get_tail();
+   add_barrier_deps(last);
+
+   memset(last_grf_write, 0, sizeof(last_grf_write));
+   memset(last_mrf_write, 0, sizeof(last_mrf_write));
+
+   /* top-to-bottom dependencies: RAW and WAW. */
+   foreach_list(node, &instructions) {
+      schedule_node *n = (schedule_node *)node;
+      vec4_instruction *inst = (vec4_instruction *)n->inst;
+
+      /* read-after-write deps. */
+      for (int i = 0; i < 3; i++) {
+         if (inst->src[i].file == GRF) {
+            add_dep(last_grf_write[inst->src[i].reg], n);
+         } else if (inst->src[i].file == HW_REG &&
+                    (inst->src[i].fixed_hw_reg.file ==
+                     BRW_GENERAL_REGISTER_FILE)) {
+            add_dep(last_fixed_grf_write, n);
+         } else if (inst->src[i].file != BAD_FILE &&
+                    inst->src[i].file != IMM &&
+                    inst->src[i].file != UNIFORM) {
+            /* No reads from MRF, and ATTR is already translated away */
+            assert(inst->src[i].file != MRF &&
+                   inst->src[i].file != ATTR);
+            add_barrier_deps(n);
+         }
+      }
+
+      for (int i = 0; i < inst->mlen; i++) {
+         /* It looks like the MRF regs are released in the send
+          * instruction once it's sent, not when the result comes
+          * back.
+          */
+         add_dep(last_mrf_write[inst->base_mrf + i], n);
+      }
+
+      if (inst->depends_on_flags()) {
+         assert(last_conditional_mod);
+         add_dep(last_conditional_mod, n);
+      }
+
+      /* write-after-write deps. */
+      if (inst->dst.file == GRF) {
+         add_dep(last_grf_write[inst->dst.reg], n);
+         last_grf_write[inst->dst.reg] = n;
+      } else if (inst->dst.file == MRF) {
+         add_dep(last_mrf_write[inst->dst.reg], n);
+         last_mrf_write[inst->dst.reg] = n;
+     } else if (inst->dst.file == HW_REG &&
+                 inst->dst.fixed_hw_reg.file == BRW_GENERAL_REGISTER_FILE) {
+         last_fixed_grf_write = n;
+      } else if (inst->dst.file != BAD_FILE) {
+         add_barrier_deps(n);
+      }
+
+      if (inst->mlen > 0) {
+         for (int i = 0; i < v->implied_mrf_writes(inst); i++) {
+            add_dep(last_mrf_write[inst->base_mrf + i], n);
+            last_mrf_write[inst->base_mrf + i] = n;
+         }
+      }
+
+      if (inst->conditional_mod) {
+         add_dep(last_conditional_mod, n, 0);
+         last_conditional_mod = n;
+      }
+   }
+
+   /* bottom-to-top dependencies: WAR */
+   memset(last_grf_write, 0, sizeof(last_grf_write));
+   memset(last_mrf_write, 0, sizeof(last_mrf_write));
+   last_conditional_mod = NULL;
+   last_fixed_grf_write = NULL;
+
+   exec_node *node;
+   exec_node *prev;
+   for (node = instructions.get_tail(), prev = node->prev;
+        !node->is_head_sentinel();
+        node = prev, prev = node->prev) {
+      schedule_node *n = (schedule_node *)node;
+      vec4_instruction *inst = (vec4_instruction *)n->inst;
+
+      /* write-after-read deps. */
+      for (int i = 0; i < 3; i++) {
+         if (inst->src[i].file == GRF) {
+            add_dep(n, last_grf_write[inst->src[i].reg]);
+         } else if (inst->src[i].file == HW_REG &&
+                    (inst->src[i].fixed_hw_reg.file ==
+                     BRW_GENERAL_REGISTER_FILE)) {
+            add_dep(n, last_fixed_grf_write);
+         } else if (inst->src[i].file != BAD_FILE &&
+                    inst->src[i].file != IMM &&
+                    inst->src[i].file != UNIFORM) {
+            assert(inst->src[i].file != MRF &&
+                   inst->src[i].file != ATTR);
+            add_barrier_deps(n);
+         }
+      }
+
+      for (int i = 0; i < inst->mlen; i++) {
+         /* It looks like the MRF regs are released in the send
+          * instruction once it's sent, not when the result comes
+          * back.
+          */
+         add_dep(n, last_mrf_write[inst->base_mrf + i], 2);
+      }
+
+      if (inst->depends_on_flags()) {
+         add_dep(n, last_conditional_mod);
+      }
+
+      /* Update the things this instruction wrote, so earlier reads
+       * can mark this as WAR dependency.
+       */
+      if (inst->dst.file == GRF) {
+         last_grf_write[inst->dst.reg] = n;
+      } else if (inst->dst.file == MRF) {
+         last_mrf_write[inst->dst.reg] = n;
+      } else if (inst->dst.file == HW_REG &&
+                 inst->dst.fixed_hw_reg.file == BRW_GENERAL_REGISTER_FILE) {
+         last_fixed_grf_write = n;
+      } else if (inst->dst.file != BAD_FILE) {
+         add_barrier_deps(n);
+      }
+
+      if (inst->mlen > 0) {
+         for (int i = 0; i < v->implied_mrf_writes(inst); i++) {
+            last_mrf_write[inst->base_mrf + i] = n;
+         }
+      }
+
+      if (inst->conditional_mod) {
+         last_conditional_mod = n;
+      }
+   }
+}
+
 schedule_node *
-instruction_scheduler::choose_instruction_to_schedule()
+fs_instruction_scheduler::choose_instruction_to_schedule()
 {
    schedule_node *chosen = NULL;
 
@@ -762,9 +964,10 @@ instruction_scheduler::choose_instruction_to_schedule()
            node != instructions.get_head()->prev;
            node = (schedule_node *)node->prev) {
          schedule_node *n = (schedule_node *)node;
+         fs_inst *inst = (fs_inst *)n->inst;
 
          chosen = n;
-         if (chosen->inst->regs_written <= 1)
+         if (inst->regs_written <= 1)
             break;
       }
    }
@@ -772,19 +975,47 @@ instruction_scheduler::choose_instruction_to_schedule()
    return chosen;
 }
 
+schedule_node *
+vec4_instruction_scheduler::choose_instruction_to_schedule()
+{
+   schedule_node *chosen = NULL;
+   int chosen_time = 0;
+
+   /* Of the instructions ready to execute or the closest to being ready,
+    * choose the oldest one.
+    */
+   foreach_list(node, &instructions) {
+      schedule_node *n = (schedule_node *)node;
+
+      if (!chosen || n->unblocked_time < chosen_time) {
+         chosen = n;
+         chosen_time = n->unblocked_time;
+      }
+   }
+
+   return chosen;
+}
+
 int
-instruction_scheduler::issue_time(fs_inst *inst)
+fs_instruction_scheduler::issue_time(backend_instruction *inst)
 {
-   if (is_compressed(inst))
+   if (is_compressed((fs_inst *)inst))
       return 4;
    else
       return 2;
 }
 
+int
+vec4_instruction_scheduler::issue_time(backend_instruction *inst)
+{
+   /* We always execute as two vec4s in parallel. */
+   return 2;
+}
+
 void
-instruction_scheduler::schedule_instructions(fs_inst *next_block_header)
+instruction_scheduler::schedule_instructions(backend_instruction *next_block_header)
 {
-   int time = 0;
+   time = 0;
 
    /* Remove non-DAG heads from the list. */
    foreach_list_safe(node, &instructions) {
@@ -816,7 +1047,7 @@ instruction_scheduler::schedule_instructions(fs_inst *next_block_header)
 
       if (debug) {
          printf("clock %4d, scheduled: ", time);
-         v->dump_instruction(chosen->inst);
+         bv->dump_instruction(chosen->inst);
       }
 
       /* Now that we've scheduled a new instruction, some of its
@@ -834,7 +1065,7 @@ instruction_scheduler::schedule_instructions(fs_inst *next_block_header)
         if (child->parent_count == 0) {
             if (debug) {
                printf("now available: ");
-               v->dump_instruction(child->inst);
+               bv->dump_instruction(child->inst);
             }
            instructions.push_tail(child);
         }
@@ -856,49 +1087,68 @@ instruction_scheduler::schedule_instructions(fs_inst *next_block_header)
       }
    }
 
-   if (unlikely(INTEL_DEBUG & DEBUG_WM) && post_reg_alloc) {
-      printf("fs%d estimated execution time: %d cycles\n",
-             v->dispatch_width, time);
-   }
-
    assert(instructions_to_schedule == 0);
 }
 
 void
-fs_visitor::schedule_instructions(bool post_reg_alloc)
+instruction_scheduler::run(exec_list *all_instructions)
 {
-   fs_inst *next_block_header = (fs_inst *)instructions.head;
-
-   int grf_count;
-   if (post_reg_alloc)
-      grf_count = grf_used;
-   else
-      grf_count = virtual_grf_count;
+   backend_instruction *next_block_header =
+      (backend_instruction *)all_instructions->head;
 
    if (debug) {
       printf("\nInstructions before scheduling (reg_alloc %d)\n", post_reg_alloc);
-      dump_instructions();
+      bv->dump_instructions();
    }
 
-   instruction_scheduler sched(this, mem_ctx, grf_count, post_reg_alloc);
-
    while (!next_block_header->is_tail_sentinel()) {
       /* Add things to be scheduled until we get to a new BB. */
       while (!next_block_header->is_tail_sentinel()) {
-        fs_inst *inst = next_block_header;
-        next_block_header = (fs_inst *)next_block_header->next;
+        backend_instruction *inst = next_block_header;
+        next_block_header = (backend_instruction *)next_block_header->next;
 
-        sched.add_inst(inst);
+        add_inst(inst);
          if (inst->is_control_flow())
            break;
       }
-      sched.calculate_deps();
-      sched.schedule_instructions(next_block_header);
+      calculate_deps();
+      schedule_instructions(next_block_header);
    }
 
    if (debug) {
       printf("\nInstructions after scheduling (reg_alloc %d)\n", post_reg_alloc);
-      dump_instructions();
+      bv->dump_instructions();
+   }
+}
+
+void
+fs_visitor::schedule_instructions(bool post_reg_alloc)
+{
+   int grf_count;
+   if (post_reg_alloc)
+      grf_count = grf_used;
+   else
+      grf_count = virtual_grf_count;
+
+   fs_instruction_scheduler sched(this, grf_count, post_reg_alloc);
+   sched.run(&instructions);
+
+   if (unlikely(INTEL_DEBUG & DEBUG_WM) && post_reg_alloc) {
+      printf("fs%d estimated execution time: %d cycles\n",
+             dispatch_width, sched.time);
+   }
+
+   this->live_intervals_valid = false;
+}
+
+void
+vec4_visitor::opt_schedule_instructions()
+{
+   vec4_instruction_scheduler sched(this, prog_data->total_grf);
+   sched.run(&instructions);
+
+   if (unlikely(debug_flag)) {
+      printf("vec4 estimated execution time: %d cycles\n", sched.time);
    }
 
    this->live_intervals_valid = false;