Mesa (master): radeonsi: implement TGSI_SEMANTIC_SUBGROUP_*

[Nicolai Hähnle]

Module: Mesa
Branch: master
Commit: a3075f479917d5685705e0a92ab4405012c1ff56
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=a3075f479917d5685705e0a92ab4405012c1ff56

Author: Nicolai Hähnle <nicolai.haehnle at amd.com>
Date:   Thu Mar 30 14:15:10 2017 +0200

radeonsi: implement TGSI_SEMANTIC_SUBGROUP_*

64-bit system values are stored as v2i32 to simplify the fetch logic.

Reviewed-by: Marek Olšák <marek.olsak at amd.com>

---

 src/gallium/drivers/radeonsi/si_shader.c | 40 ++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c
index 600f2e3102..6e8b6746b9 100644
--- a/src/gallium/drivers/radeonsi/si_shader.c
+++ b/src/gallium/drivers/radeonsi/si_shader.c
@@ -1586,6 +1586,46 @@ static void declare_system_value(struct si_shader_context *ctx,
 		}
 		break;
 
+	case TGSI_SEMANTIC_SUBGROUP_SIZE:
+		value = LLVMConstInt(ctx->i32, 64, 0);
+		break;
+
+	case TGSI_SEMANTIC_SUBGROUP_INVOCATION:
+		value = ac_get_thread_id(&ctx->ac);
+		break;
+
+	case TGSI_SEMANTIC_SUBGROUP_EQ_MASK:
+	{
+		LLVMValueRef id = ac_get_thread_id(&ctx->ac);
+		id = LLVMBuildZExt(gallivm->builder, id, ctx->i64, "");
+		value = LLVMBuildShl(gallivm->builder, LLVMConstInt(ctx->i64, 1, 0), id, "");
+		value = LLVMBuildBitCast(gallivm->builder, value, ctx->v2i32, "");
+		break;
+	}
+
+	case TGSI_SEMANTIC_SUBGROUP_GE_MASK:
+	case TGSI_SEMANTIC_SUBGROUP_GT_MASK:
+	case TGSI_SEMANTIC_SUBGROUP_LE_MASK:
+	case TGSI_SEMANTIC_SUBGROUP_LT_MASK:
+	{
+		LLVMValueRef id = ac_get_thread_id(&ctx->ac);
+		if (decl->Semantic.Name == TGSI_SEMANTIC_SUBGROUP_GT_MASK ||
+		    decl->Semantic.Name == TGSI_SEMANTIC_SUBGROUP_LE_MASK) {
+			/* All bits set except LSB */
+			value = LLVMConstInt(ctx->i64, -2, 0);
+		} else {
+			/* All bits set */
+			value = LLVMConstInt(ctx->i64, -1, 0);
+		}
+		id = LLVMBuildZExt(gallivm->builder, id, ctx->i64, "");
+		value = LLVMBuildShl(gallivm->builder, value, id, "");
+		if (decl->Semantic.Name == TGSI_SEMANTIC_SUBGROUP_LE_MASK ||
+		    decl->Semantic.Name == TGSI_SEMANTIC_SUBGROUP_LT_MASK)
+			value = LLVMBuildNot(gallivm->builder, value, "");
+		value = LLVMBuildBitCast(gallivm->builder, value, ctx->v2i32, "");
+		break;
+	}
+
 	default:
 		assert(!"unknown system value");
 		return;