radeonsi: implement TGSI_SEMANTIC_SUBGROUP_*

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

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

diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c
index 600f2e310293beeac0418654b63cf1e71b370a9e..6e8b6746b9d1b380048cb0f7f10788f5aba33d93 100644 (file)
--- 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;