Translate LLVM 23 vector splat constants in Iridium

LLVM 23 represents vector splats such as `<3 x float> zeroinitializer`
as vector-typed ConstantFP/ConstantInt values instead of
ConstantAggregateZero/ConstantDataVector. Iridium only handled scalar
ConstantFP/ConstantInt, so on hosts with LLVM 23 nearly every League
shader failed to translate: the r3dlog fills with "Failed to compile
shader", the loading screen hits "Material Missing Pipeline" and the
game crashes. Our matches had only run the overlay pinned to LLVM 22.

Declare the scalar element and splat it into a constant composite.
Offline, on the 74,112 metallibs in ShaderCache.metal.wad.client,
LLVM 23 went from ~2% to 74,108 translated, the same set as LLVM 22
(the 4 remaining failures are pre-existing on both); a sample of the
LLVM 23 SPIR-V passes spirv-val for Vulkan 1.3. Confirmed in a match
with the Iridium overlay built against the system LLVM 23.

RIOT_IRIDIUM_SYSTEM_LLVM=1 makes build-riot-indium-runtime.py ignore
the LLVM 22 pin, to build what a fresh checkout gets.

Refs #1

Co-Authored-By: Claude Opus 5.5 <[email protected]>

docs/TROUBLESHOOTING.md

@@ -135,6 +135,7 @@ A separate multi-window path stopped the active async presenter when another dif
 - **OpenDirectory 32-bit ivar errors:** keep `TARGET_i386=OFF`; the supported client is x86-64.
 - **Undefined empty Objective-C collection symbols:** retain the patched macOS 10.15 Objective-C runtime code generation.
 - **LLVM branch opcode errors:** retain the Indium LLVM 22/23 compatibility patch; do not replace its branch handling with an unconditional version-specific opcode.
+- **Every game shader fails to compile on LLVM 23** (r3dlog full of `Failed to compile shader`, then `Material Missing Pipeline` and a crash before the loading screen; `/tmp/metal-errors.log` shows `Unsupported LLVM value: <3 x float> zeroinitializer`): LLVM 23 represents vector splats as vector-typed `ConstantFP`/`ConstantInt`, which Iridium did not translate. Indium now splats them itself. Rebuild and reinstall the Metal/Indium pair ([setup](SETUP.md#metal-and-indium-overlays)). The offline check `python3 tools/build-riot-air-check.py --native` translates shader libraries without the game.
 - **Build process killed:** lower parallelism, for example `JOBS=2 ./scripts/build.sh` or `--parallel 1` for an incremental component build.
 - **Incremental helper cannot find `flags.make` or `link.txt`:** use Unix Makefiles, not Ninja.
 - **Prebuilt Swift file contains Git LFS pointer text:** install Git LFS and fetch the original upstream assets; pointer text is not a usable library.

patches/metal--deps--indium.patch

@@ -4802,7 +4802,7 @@ index 1e3e971..4db87d4 100644
 -	DynamicVK::vkFreeCommandBuffers(_device->device(), _device->oneshotCommandPool(), 1, &cmdBuf);
  };
 diff --git a/src/iridium/air.cpp b/src/iridium/air.cpp
-index 21c501f..24423e3 100644
+index 21c501f..9f6663b 100644
 --- a/src/iridium/air.cpp
 +++ b/src/iridium/air.cpp
 @@ -4,9 +4,46 @@
@@ -5008,7 +5008,7 @@ index 21c501f..24423e3 100644
  		} break;
  
  		default:
-@@ -162,14 +299,32 @@ static Iridium::SPIRV::ResultID llvmValueToResultID(Iridium::SPIRV::Builder& bui
+@@ -162,14 +299,60 @@ static Iridium::SPIRV::ResultID llvmValueToResultID(Iridium::SPIRV::Builder& bui
  	{
  		ResultID maybe = builder.lookupResultID(reinterpret_cast<uintptr_t>(llvmValue));
  		if (maybe != ResultIDInvalid) {
@@ -5017,6 +5017,34 @@ index 21c501f..24423e3 100644
  		}
  	}
  
++	// LLVM 23 represents vector splats (e.g. `<3 x float> zeroinitializer`) as vector-typed ConstantInt/ConstantFP values
++	// rather than ConstantAggregateZero/ConstantDataVector. Declare the scalar and splat it into a composite.
++	if ((kind == LLVMConstantIntValueKind || kind == LLVMConstantFPValueKind) && typeKind == LLVMVectorTypeKind) {
++		auto elementType = DynamicLLVM::LLVMGetElementType(type);
++		auto elementKind = DynamicLLVM::LLVMGetTypeKind(elementType);
++		ResultID element = ResultIDInvalid;
++		if (kind == LLVMConstantIntValueKind) {
++			auto val = DynamicLLVM::LLVMConstIntGetZExtValue(llvmValue);
++			auto width = DynamicLLVM::LLVMGetIntTypeWidth(elementType);
++			element = width == 1 ? builder.declareConstantBool(val != 0) : ((width <= 32) ? builder.declareConstantScalar<int32_t>(val) : builder.declareConstantScalar<int64_t>(val));
++		} else {
++			LLVMBool losesInfo = false;
++			auto val = DynamicLLVM::LLVMConstRealGetDouble(llvmValue, &losesInfo);
++			switch (elementKind) {
++				case LLVMFloatTypeKind: element = builder.declareConstantScalar<float>(val); break;
++				case LLVMDoubleTypeKind: element = builder.declareConstantScalar<double>(val); break;
++				case LLVMHalfTypeKind: {
++					Iridium::Float16 tmp = val;
++					element = builder.declareConstantScalar<const Iridium::Float16*>(&tmp);
++				} break;
++				default:
++					throw ImpossibleResultID("Unsupported LLVM value: " + describeLLVMValue(llvmValue));
++			}
++		}
++		std::vector<ResultID> vals(DynamicLLVM::LLVMGetVectorSize(type), element);
++		return builder.declareConstantComposite(llvmTypeToSPIRVType(builder, type), vals);
++	}
++
  	switch (kind) {
 +        case LLVMGlobalVariableValueKind: {
 +            auto initializer = DynamicLLVM::LLVMGetInitializer(llvmValue);
@@ -5041,7 +5069,7 @@ index 21c501f..24423e3 100644
  			// TODO: how to determine if it's signed or not?
  			return (width <= 32) ? builder.declareConstantScalar<int32_t>(val) : builder.declareConstantScalar<int64_t>(val);
  		} break;
-@@ -191,13 +346,15 @@ static Iridium::SPIRV::ResultID llvmValueToResultID(Iridium::SPIRV::Builder& bui
+@@ -191,13 +374,15 @@ static Iridium::SPIRV::ResultID llvmValueToResultID(Iridium::SPIRV::Builder& bui
  				} break;
  
  				default:
@@ -5060,7 +5088,7 @@ index 21c501f..24423e3 100644
  
  			for (size_t i = 0; i < count; ++i) {
  				auto constant = DynamicLLVM::LLVMGetOperand(llvmValue, i);
-@@ -207,10 +364,11 @@ static Iridium::SPIRV::ResultID llvmValueToResultID(Iridium::SPIRV::Builder& bui
+@@ -207,10 +392,11 @@ static Iridium::SPIRV::ResultID llvmValueToResultID(Iridium::SPIRV::Builder& bui
  			return builder.declareConstantComposite(llvmTypeToSPIRVType(builder, type), vals);
  		} break;
  
@@ -5074,7 +5102,7 @@ index 21c501f..24423e3 100644
  
  			for (size_t i = 0; i < count; ++i) {
  				auto constant = DynamicLLVM::LLVMGetElementAsConstant(llvmValue, i);
-@@ -220,7 +378,8 @@ static Iridium::SPIRV::ResultID llvmValueToResultID(Iridium::SPIRV::Builder& bui
+@@ -220,7 +406,8 @@ static Iridium::SPIRV::ResultID llvmValueToResultID(Iridium::SPIRV::Builder& bui
  			return builder.declareConstantComposite(llvmTypeToSPIRVType(builder, type), vals);
  		} break;
  
@@ -5084,7 +5112,7 @@ index 21c501f..24423e3 100644
  			return builder.declareUndefinedValue(llvmTypeToSPIRVType(builder, type));
  		} break;
  
-@@ -231,6 +390,21 @@ static Iridium::SPIRV::ResultID llvmValueToResultID(Iridium::SPIRV::Builder& bui
+@@ -231,6 +418,21 @@ static Iridium::SPIRV::ResultID llvmValueToResultID(Iridium::SPIRV::Builder& bui
  
  		case LLVMConstantExprValueKind: {
  			switch (DynamicLLVM::LLVMGetConstOpcode(llvmValue)) {
@@ -5106,7 +5134,7 @@ index 21c501f..24423e3 100644
  				case LLVMBitCast: {
  					auto target = DynamicLLVM::LLVMGetOperand(llvmValue, 0);
  					auto targetID = llvmValueToResultID(builder, target);
-@@ -254,13 +428,315 @@ static Iridium::SPIRV::ResultID llvmValueToResultID(Iridium::SPIRV::Builder& bui
+@@ -254,13 +456,315 @@ static Iridium::SPIRV::ResultID llvmValueToResultID(Iridium::SPIRV::Builder& bui
  				} break;
  
  				default:
@@ -5139,7 +5167,7 @@ index 21c501f..24423e3 100644
 +static bool airTypeTokenIsFloat(std::string_view token) {
 +	if (token.empty()) {
 +		return false;
-+	}
+ 	}
 +	if (token[0] == 'v') {
 +		token.remove_prefix(1);
 +		while (!token.empty() && token[0] >= '0' && token[0] <= '9') {
@@ -5418,13 +5446,13 @@ index 21c501f..24423e3 100644
 +			return false;
 +		}
 +		return true;
- 	}
++	}
 +
 +	return false;
  };
  
  void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& outputInfo) {
-@@ -312,7 +788,7 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -312,7 +816,7 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  		});
  
  		// declare the GLSL PerVertex structure
@@ -5433,7 +5461,7 @@ index 21c501f..24423e3 100644
  			SPIRV::Type::Member {
  				vec4Type,
  				0,
-@@ -321,13 +797,21 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -321,13 +825,21 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  				}
  			},
  			// TODO: declare the rest of the structure
@@ -5456,7 +5484,7 @@ index 21c501f..24423e3 100644
  
  		// declare the GLSL VertexIndex input variable
  		vertexIndexVar = builder.addGlobalVariable(ptrIntType, SPIRV::StorageClass::Input);
-@@ -425,7 +909,7 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -425,7 +937,7 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  	// if the function returns a structure, we need to separate the components
  	// into separate output variables.
  
@@ -5465,7 +5493,7 @@ index 21c501f..24423e3 100644
  	auto funcRetType = DynamicLLVM::LLVMGetReturnType(llfuncType);
  	std::vector<LLVMTypeRef> funcParamTypes(DynamicLLVM::LLVMCountParamTypes(llfuncType));
  	DynamicLLVM::LLVMGetParamTypes(llfuncType, funcParamTypes.data());
-@@ -460,7 +944,7 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -460,7 +972,7 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  				auto type = llvmTypeToSPIRVType(builder, DynamicLLVM::LLVMStructGetTypeAtIndex(funcRetType, i));
  				auto ptrType = builder.declareType(SPIRV::Type(SPIRV::Type::PointerTag {}, SPIRV::StorageClass::Output, type, 8));
  				auto var = builder.addGlobalVariable(ptrType, SPIRV::StorageClass::Output);
@@ -5474,7 +5502,7 @@ index 21c501f..24423e3 100644
  				++location;
  				_outputValueIDs.push_back(var);
  				builder.referenceGlobalVariable(var);
-@@ -472,13 +956,60 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -472,13 +984,60 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  		auto type = llvmTypeToSPIRVType(builder, funcRetType);
  		auto ptrType = builder.declareType(SPIRV::Type(SPIRV::Type::PointerTag {}, SPIRV::StorageClass::Output, type, 8));
  		auto var = builder.addGlobalVariable(ptrType, SPIRV::StorageClass::Output);
@@ -5536,7 +5564,7 @@ index 21c501f..24423e3 100644
  
  	//
  	// analyze parameters and mark special values (like the vertex ID)
-@@ -519,7 +1050,9 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -519,7 +1078,9 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  			auto kind = llvmMDStringToStringView(parameterInfo[1]);
  
  			if (kind == "air.buffer") {
@@ -5547,7 +5575,7 @@ index 21c501f..24423e3 100644
  				auto addrPtrTypeInst = SPIRV::Type(SPIRV::Type::PointerTag {}, SPIRV::StorageClass::PhysicalStorageBuffer, type, 8);
  				auto addrPtrType = builder.declareType(addrPtrTypeInst);
  				bufferMembers.push_back(SPIRV::Type::Member { addrPtrType, 8 * bufferIndex, {} });
-@@ -575,7 +1108,21 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -575,7 +1136,21 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  			_parameterIDs.push_back(load);
  			builder.associateExistingResultID(load, llparamVal);
  			builder.setResultType(load, intType);
@@ -5570,7 +5598,7 @@ index 21c501f..24423e3 100644
  			// find the location index info
  			size_t infoIdx = 0;
  			for (; infoIdx < parameterInfo.size(); ++infoIdx) {
-@@ -620,7 +1167,7 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -620,7 +1195,7 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  			auto var = builder.addGlobalVariable(ptrType, SPIRV::StorageClass::Input);
  			auto load = builder.encodeLoad(type, var);
  
@@ -5579,7 +5607,7 @@ index 21c501f..24423e3 100644
  			++paramLocation;
  
  			builder.referenceGlobalVariable(var);
-@@ -631,9 +1178,18 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -631,9 +1206,18 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  			builder.setResultType(load, type);
  		} else if (kind == "air.vertex_input") {
  			auto type = llvmTypeToSPIRVType(builder, funcParamTypes[i]);
@@ -5600,7 +5628,7 @@ index 21c501f..24423e3 100644
  
  			// find the location index info
  			size_t infoIdx = 0;
-@@ -761,14 +1317,19 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -761,14 +1345,19 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  				realSampleType = fakeSampleType;
  			}
  
@@ -5628,7 +5656,7 @@ index 21c501f..24423e3 100644
  			auto imagePtrType = builder.declareType(SPIRV::Type(SPIRV::Type::PointerTag {}, SPIRV::StorageClass::UniformConstant, imageType, 8));
  			auto var = builder.addGlobalVariable(imagePtrType, SPIRV::StorageClass::UniformConstant);
  			//auto load = builder.encodeLoad(imageType, var);
-@@ -959,68 +1520,98 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -959,68 +1548,98 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  	enum class CFGType {
  		None = 0,
  		Selection,
@@ -5776,7 +5804,7 @@ index 21c501f..24423e3 100644
  		if (isFirst) {
  			isFirst = false;
  
-@@ -1030,16 +1621,54 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -1030,16 +1649,54 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  			builder.insertLabel(builder.lookupResultID(reinterpret_cast<uintptr_t>(bb)));
  		}
  
@@ -5832,7 +5860,7 @@ index 21c501f..24423e3 100644
  
  					builder.associateExistingResultID(resID, reinterpret_cast<uintptr_t>(inst));
  					builder.setResultType(resID, type);
-@@ -1048,6 +1677,18 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -1048,6 +1705,18 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  				// TODO: look into using physical addressing instead of logical addressing, which should simplify the translation process
  				//       (since i *think* that's the same addressing mode used by Metal code)
  
@@ -5851,7 +5879,7 @@ index 21c501f..24423e3 100644
  				case LLVMGetElementPtr: {
  					auto base = DynamicLLVM::LLVMGetOperand(inst, 0);
  					auto targetType = DynamicLLVM::LLVMTypeOf(inst);
-@@ -1060,17 +1701,32 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -1060,17 +1729,32 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  						indices.push_back(llvmValueToResultID(builder, llindex));
  					}
  
@@ -5885,7 +5913,7 @@ index 21c501f..24423e3 100644
  					// strangely enough, SPIR-V provides no instruction that can do an initial pointer offset like LLVM's GEP does.
  					// there's OpPtrAccessChain, which is tantalizingly named, but unfortunately that instruction doesn't work as expected
  					// either. i've tried using the raw index (i.e. in element units) and the multiplied index (i.e. in bytes), but no dice.
-@@ -1112,6 +1768,9 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -1112,6 +1796,9 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  						op = access;
  					}
  
@@ -5895,7 +5923,7 @@ index 21c501f..24423e3 100644
  					auto resID = builder.encodeLoad(type, op, alignment);
  
  					builder.associateExistingResultID(resID, reinterpret_cast<uintptr_t>(inst));
-@@ -1149,50 +1808,8 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -1149,50 +1836,8 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  						auto arg = DynamicLLVM::LLVMGetOperand(inst, 0);
  
  						resID = builder.encodeConvertUToF(type, llvmValueToResultID(builder, arg));
@@ -5948,7 +5976,7 @@ index 21c501f..24423e3 100644
  						auto arg = DynamicLLVM::LLVMGetOperand(inst, 0);
  
  						resID = builder.encodeFConvert(type, llvmValueToResultID(builder, arg));
-@@ -1223,14 +1840,33 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -1223,14 +1868,33 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  						auto operand2 = DynamicLLVM::LLVMGetOperand(inst, 1);
  
  						resID = builder.encodeFMax(type, llvmValueToResultID(builder, operand1), llvmValueToResultID(builder, operand2));
@@ -5985,7 +6013,7 @@ index 21c501f..24423e3 100644
  				case LLVMFMul:
  				case LLVMFDiv:
  				case LLVMFAdd:
-@@ -1365,28 +2001,81 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -1365,28 +2029,81 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  					auto op1 = DynamicLLVM::LLVMGetOperand(inst, 0);
  					auto op2 = DynamicLLVM::LLVMGetOperand(inst, 1);
  					auto predicate = DynamicLLVM::LLVMGetFCmpPredicate(inst);
@@ -6016,16 +6044,16 @@ index 21c501f..24423e3 100644
 +						default:
 +							throw std::runtime_error("TODO: handle fcmp predicate: " + std::to_string(predicate));
 +					}
++
++					auto resID = builder.encodeRawOp(spirvOpcode, type, { llvmValueToResultID(builder, op1), llvmValueToResultID(builder, op2) });
  
 -						case LLVMRealOLT: {
 -							resID = builder.encodeFOrdLessThan(llvmValueToResultID(builder, op1), llvmValueToResultID(builder, op2));
 -						} break;
-+					auto resID = builder.encodeRawOp(spirvOpcode, type, { llvmValueToResultID(builder, op1), llvmValueToResultID(builder, op2) });
- 
 +					builder.associateExistingResultID(resID, reinterpret_cast<uintptr_t>(inst));
 +					builder.setResultType(resID, type);
 +				} break;
-+
+ 
 +				case LLVMICmp: {
 +					auto op1 = DynamicLLVM::LLVMGetOperand(inst, 0);
 +					auto op2 = DynamicLLVM::LLVMGetOperand(inst, 1);
@@ -6051,11 +6079,10 @@ index 21c501f..24423e3 100644
  
 +					auto resID = builder.encodeRawOp(spirvOpcode, type, { llvmValueToResultID(builder, op1), llvmValueToResultID(builder, op2) });
 +
- 					builder.associateExistingResultID(resID, reinterpret_cast<uintptr_t>(inst));
- 					builder.setResultType(resID, type);
- 				} break;
- 
--				case LLVMBr: {
++					builder.associateExistingResultID(resID, reinterpret_cast<uintptr_t>(inst));
++					builder.setResultType(resID, type);
++				} break;
++
 +				case LLVMSelect: {
 +					auto type = llvmTypeToSPIRVType(builder, DynamicLLVM::LLVMTypeOf(inst));
 +					auto resID = builder.encodeRawOp(SPIRVOp::Select, type, {
@@ -6064,10 +6091,11 @@ index 21c501f..24423e3 100644
 +						llvmValueToResultID(builder, DynamicLLVM::LLVMGetOperand(inst, 2)),
 +					});
 +
-+					builder.associateExistingResultID(resID, reinterpret_cast<uintptr_t>(inst));
-+					builder.setResultType(resID, type);
-+				} break;
-+
+ 					builder.associateExistingResultID(resID, reinterpret_cast<uintptr_t>(inst));
+ 					builder.setResultType(resID, type);
+ 				} break;
+ 
+-				case LLVMBr: {
 +				IRIDIUM_BR_CASES: {
 +                    auto loop=cfgInfos.find(builder.lookupResultID(reinterpret_cast<uintptr_t>(bb)));
 +                    if(loop!=cfgInfos.end() && loop->second.type==CFGType::Loop){
@@ -6078,7 +6106,7 @@ index 21c501f..24423e3 100644
  					if (DynamicLLVM::LLVMIsConditional(inst)) {
  						auto condition = DynamicLLVM::LLVMGetCondition(inst);
  						auto trueLabel = DynamicLLVM::LLVMBasicBlockAsValue(DynamicLLVM::LLVMGetSuccessor(inst, 0));
-@@ -1422,25 +2111,38 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -1422,25 +2139,38 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  					auto type = llvmTypeToSPIRVType(builder, lltype);
  
  					std::vector<std::pair<SPIRV::ResultID, SPIRV::ResultID>> variablesAndBlocks;
@@ -6120,7 +6148,7 @@ index 21c501f..24423e3 100644
  
  					// ensure the resulting pointer storage class is the same as the input pointer storage class
  					auto typeInst = *builder.reverseLookupType(type);
-@@ -1474,6 +2176,7 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
+@@ -1474,6 +2204,7 @@ void Iridium::AIR::Function::analyze(SPIRV::Builder& builder, OutputInfo& output
  		}
  	}
  

tools/build-riot-indium-runtime.py

@@ -1,6 +1,7 @@
 #!/usr/bin/env python3
 """Build the paired Iridium shader translator and Indium runtime overrides."""
 from pathlib import Path
+import os
 import shlex
 import subprocess
 import sys
@@ -17,7 +18,8 @@ for line in (folder / 'CMakeFiles/iridium.dir/flags.make').read_text().splitline
         key, value = line.split(' = ', 1)
         iridium_flags[key] = shlex.split(value)
 iridium_flags['CXX_INCLUDES'] = current_includes(iridium_flags['CXX_INCLUDES'])
-if (pinned_llvm / 'lib/libLLVM-22.so').exists():
+# RIOT_IRIDIUM_SYSTEM_LLVM=1 ignores the pin and builds against the host LLVM, as a fresh checkout does.
+if (pinned_llvm / 'lib/libLLVM-22.so').exists() and os.environ.get('RIOT_IRIDIUM_SYSTEM_LLVM') != '1':
     iridium_flags['CXX_INCLUDES'].insert(0, '-I' + str(pinned_llvm / 'include'))
     iridium_flags['CXX_DEFINES'] = [value for value in iridium_flags['CXX_DEFINES'] if not value.startswith('-DHOST_LLVM_LIBNAME=')]
     iridium_flags['CXX_DEFINES'].append('-DHOST_LLVM_LIBNAME="' + str(pinned_llvm / 'lib/libLLVM-22.so') + '"')