Mesa (master): nir: Add intrinsics from ARB_shader_ballot

[Matt Turner]

Module: Mesa
Branch: master
Commit: 636fe4d1c6b21e9efecd4bce1cedd67afa33343a
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=636fe4d1c6b21e9efecd4bce1cedd67afa33343a

Author: Matt Turner <mattst88 at gmail.com>
Date:   Thu Jun 22 16:43:24 2017 -0700

nir: Add intrinsics from ARB_shader_ballot

Reviewed-by: Connor Abbott <cwabbott0 at gmail.com>
Reviewed-by: Kenneth Graunke <kenneth at whitecape.org>

---

 src/compiler/glsl/glsl_to_nir.cpp | 45 +++++++++++++++++++++++++++++++++++++++
 src/compiler/nir/nir_intrinsics.h | 13 +++++++++++
 2 files changed, 58 insertions(+)

diff --git a/src/compiler/glsl/glsl_to_nir.cpp b/src/compiler/glsl/glsl_to_nir.cpp
index 01166f6865..4b3dbcff17 100644
--- a/src/compiler/glsl/glsl_to_nir.cpp
+++ b/src/compiler/glsl/glsl_to_nir.cpp
@@ -808,6 +808,15 @@ nir_visitor::visit(ir_call *ir)
       case ir_intrinsic_vote_eq:
          op = nir_intrinsic_vote_eq;
          break;
+      case ir_intrinsic_ballot:
+         op = nir_intrinsic_ballot;
+         break;
+      case ir_intrinsic_read_invocation:
+         op = nir_intrinsic_read_invocation;
+         break;
+      case ir_intrinsic_read_first_invocation:
+         op = nir_intrinsic_read_first_invocation;
+         break;
       default:
          unreachable("not reached");
       }
@@ -1157,6 +1166,42 @@ nir_visitor::visit(ir_call *ir)
          nir_builder_instr_insert(&b, &instr->instr);
          break;
       }
+
+      case nir_intrinsic_ballot: {
+         nir_ssa_dest_init(&instr->instr, &instr->dest,
+                           ir->return_deref->type->vector_elements, 64, NULL);
+
+         ir_rvalue *value = (ir_rvalue *) ir->actual_parameters.get_head();
+         instr->src[0] = nir_src_for_ssa(evaluate_rvalue(value));
+
+         nir_builder_instr_insert(&b, &instr->instr);
+         break;
+      }
+      case nir_intrinsic_read_invocation: {
+         nir_ssa_dest_init(&instr->instr, &instr->dest,
+                           ir->return_deref->type->vector_elements, 32, NULL);
+         instr->num_components = ir->return_deref->type->vector_elements;
+
+         ir_rvalue *value = (ir_rvalue *) ir->actual_parameters.get_head();
+         instr->src[0] = nir_src_for_ssa(evaluate_rvalue(value));
+
+         ir_rvalue *invocation = (ir_rvalue *) ir->actual_parameters.get_head()->next;
+         instr->src[1] = nir_src_for_ssa(evaluate_rvalue(invocation));
+
+         nir_builder_instr_insert(&b, &instr->instr);
+         break;
+      }
+      case nir_intrinsic_read_first_invocation: {
+         nir_ssa_dest_init(&instr->instr, &instr->dest,
+                           ir->return_deref->type->vector_elements, 32, NULL);
+         instr->num_components = ir->return_deref->type->vector_elements;
+
+         ir_rvalue *value = (ir_rvalue *) ir->actual_parameters.get_head();
+         instr->src[0] = nir_src_for_ssa(evaluate_rvalue(value));
+
+         nir_builder_instr_insert(&b, &instr->instr);
+         break;
+      }
       default:
          unreachable("not reached");
       }
diff --git a/src/compiler/nir/nir_intrinsics.h b/src/compiler/nir/nir_intrinsics.h
index 8a838df027..6c6ba4cf59 100644
--- a/src/compiler/nir/nir_intrinsics.h
+++ b/src/compiler/nir/nir_intrinsics.h
@@ -94,6 +94,19 @@ BARRIER(memory_barrier)
 INTRINSIC(shader_clock, 0, ARR(0), true, 2, 0, 0, xx, xx, xx, NIR_INTRINSIC_CAN_ELIMINATE)
 
 /*
+ * Shader ballot intrinsics with semantics analogous to the
+ *
+ *    ballotARB()
+ *    readInvocationARB()
+ *    readFirstInvocationARB()
+ *
+ * GLSL functions from ARB_shader_ballot.
+ */
+INTRINSIC(ballot, 1, ARR(1), true, 1, 0, 0, xx, xx, xx, NIR_INTRINSIC_CAN_ELIMINATE)
+INTRINSIC(read_invocation, 2, ARR(0, 1), true, 0, 0, 0, xx, xx, xx, NIR_INTRINSIC_CAN_ELIMINATE)
+INTRINSIC(read_first_invocation, 1, ARR(0), true, 0, 0, 0, xx, xx, xx, NIR_INTRINSIC_CAN_ELIMINATE)
+
+/*
  * Memory barrier with semantics analogous to the compute shader
  * groupMemoryBarrier(), memoryBarrierAtomicCounter(), memoryBarrierBuffer(),
  * memoryBarrierImage() and memoryBarrierShared() GLSL intrinsics.