glsl/spirv: Emit GLSL tessellation shader special output variables in SPIR-V

v2: Return 0 for unsupported cases instead of failing an assertion.

2 files changed, 35 insertions, 4 deletions

diff --git a/src/compiler/glsl/glsl_to_spirv.cpp b/src/compiler/glsl/glsl_to_spirv.cpp
index b383b158e68..8c3ab18bf92 100644
--- a/src/compiler/glsl/glsl_to_spirv.cpp
+++ b/src/compiler/glsl/glsl_to_spirv.cpp
@@ -682,14 +682,25 @@ _mesa_spirv_program::emit_variable(const ir_variable *var,
                builtin = SpvBuiltInViewportIndex;
                break;
 
-            case VARYING_SLOT_PRIMITIVE_ID:
-            case VARYING_SLOT_FACE:
-            case VARYING_SLOT_PNTC:
             case VARYING_SLOT_TESS_LEVEL_OUTER:
+               assert(stage == MESA_SHADER_TESS_CTRL);
+               builtin = SpvBuiltInTessLevelOuter;
+               break;
+
             case VARYING_SLOT_TESS_LEVEL_INNER:
-            case VARYING_SLOT_EDGE:
+               assert(stage == MESA_SHADER_TESS_CTRL);
+               builtin = SpvBuiltInTessLevelInner;
+               break;
+
             case VARYING_SLOT_BOUNDING_BOX0:
             case VARYING_SLOT_BOUNDING_BOX1:
+               /* FINISHME: Handle gl_BoundingBox. */
+               break;
+
+            case VARYING_SLOT_PRIMITIVE_ID:
+            case VARYING_SLOT_FACE:
+            case VARYING_SLOT_PNTC:
+            case VARYING_SLOT_EDGE:
             default:
                unreachable("Invalid shader output.");
             }
diff --git a/src/compiler/glsl/tests/emit_spirv_variables_test.cpp b/src/compiler/glsl/tests/emit_spirv_variables_test.cpp
index 9b360622683..446cf000dd4 100644
--- a/src/compiler/glsl/tests/emit_spirv_variables_test.cpp
+++ b/src/compiler/glsl/tests/emit_spirv_variables_test.cpp
@@ -1065,6 +1065,16 @@ TEST_F(validate_emit_fragment_variable, input_gl_ViewportIndex)
    EXPECT_TRUE(spv->capabilities.is_enabled(SpvCapabilityMultiViewport));
 }
 
+TEST_F(validate_emit_tess_ctrl_variable, output_gl_TessLevelOuter)
+{
+   check_builtin_output(shader_output(VARYING_SLOT_TESS_LEVEL_OUTER,
+                                      array4_float,
+                                      "gl_TessLevelOuter"),
+                        0x0000000b);
+
+   EXPECT_TRUE(spv->capabilities.is_enabled(SpvCapabilityTessellation));
+}
+
 TEST_F(validate_emit_tess_eval_variable, input_gl_TessLevelOuter)
 {
    /* gl_TessLevelOuter is interesting because some drivers treat it as an
@@ -1089,6 +1099,16 @@ TEST_F(validate_emit_tess_eval_variable, sysval_gl_TessLevelOuter)
                        0x0000000b);
 }
 
+TEST_F(validate_emit_tess_ctrl_variable, output_gl_TessLevelInner)
+{
+   check_builtin_output(shader_output(VARYING_SLOT_TESS_LEVEL_INNER,
+                                      array2_float,
+                                      "gl_TessLevelInner"),
+                        0x0000000c);
+
+   EXPECT_TRUE(spv->capabilities.is_enabled(SpvCapabilityTessellation));
+}
+
 TEST_F(validate_emit_tess_eval_variable, input_gl_TessLevelInner)
 {
    /* gl_TessLevelInner is interesting because some drivers treat it as an