shader: ignore inactive auxiliary position exports

src/graphics/shader/recompiler/ir/ShaderIR.h

@@ -184,7 +184,6 @@ enum class StageOutputKind {
 struct PositionExportComponent {
 	uint32_t clip_distance = UINT32_MAX;
 	uint32_t cull_distance = UINT32_MAX;
-	bool     valid          = false;
 	bool     point_size     = false;
 	bool     layer          = false;
 	bool     viewport       = false;
@@ -213,7 +212,6 @@ inline PositionExportComponent DecodePositionExportComponent(uint32_t control,
 		return result;
 	}
 
-	result.valid = true;
 	if (vector == 0) {
 		result.point_size = component == 0 && (control & (1u << 16u)) != 0;
 		result.layer      = component == 2 && (control & (1u << 18u)) != 0;

src/graphics/shader/recompiler/ir/passes/ShaderInfoCollection.cpp

@@ -311,10 +311,6 @@ void CollectOutputs(const Program& program, const ShaderVertexInputInfo* vertex,
 						}
 						const auto output = DecodePositionExportComponent(
 						    vertex->pa_cl_vs_out_cntl, export_info.index, component);
-						if (!output.valid) {
-							return Fail(fmt::format("unsupported POS{} auxiliary/stereo export",
-							                        export_info.index));
-						}
 						if (output.viewport) {
 							return Fail("vertex viewport-index export is unsupported");
 						}

tests/shaderCfgTests.cpp

@@ -9062,6 +9062,18 @@ void TestNewShaderRecompilerAuxPositionExports() {
                 std::vector<uint32_t>({0u}),
         "CCDIST1 did not shift across a disabled CCDIST0 vector");
 
+  const uint32_t unmapped[] = {
+      EncodeExp0(0x0d, 0x4, false), EncodeExp1(0, 0, 8, 0),
+      EncodeExp0(0x0c, 0xf), EncodeExp1(0, 1, 2, 3),
+      0xbf810000u,
+  };
+  const auto ignored = compile(unmapped, 0u);
+  CheckSpirvBinaryValidates(ignored.spirv);
+  Check(ignored.program.info.outputs.size() == 1u &&
+            ignored.program.info.outputs[0].kind ==
+                ShaderRecompiler::IR::StageOutputKind::Position,
+        "unmapped auxiliary position export was not ignored");
+
 #if KYTY_PLATFORM != KYTY_PLATFORM_WINDOWS
   const auto rejects = [](uint32_t control, uint32_t en,
                           const char *message) {
@@ -9080,9 +9092,6 @@ void TestNewShaderRecompilerAuxPositionExports() {
   rejects(0x00280000u, 0x4u,
           "viewport-index auxiliary position export did not terminate "
           "compilation");
-  rejects(0u, 0x1u,
-          "unsupported auxiliary/stereo position export did not terminate "
-          "compilation");
 #endif
 
   ShaderVertexInputInfo key0{};