https://github.com/Fznamznon created https://github.com/llvm/llvm-project/pull/224609
Similar to CXXABILowering and LowerToLLVM, target lowering should also transform unreacheable blocks to avoid legalization failures. >From 1d801ff87af12b0306f6020c779fd5eaee883e68 Mon Sep 17 00:00:00 2001 From: Mariya Podchishchaeva <[email protected]> Date: Fri, 18 Sep 2026 06:41:46 -0500 Subject: [PATCH] [CIR] Unreacheable blocks should be target lowered Similar to CXXABILowering and LowerToLLVM, target lowering should also transform unreacheable blocks to avoid legalization failures. --- .../CIR/Dialect/Transforms/TargetLowering.cpp | 7 +++- .../CodeGen/target-lowering-dead-block.cpp | 34 +++++++++++++++++++ 2 files changed, 40 insertions(+), 1 deletion(-) create mode 100644 clang/test/CIR/CodeGen/target-lowering-dead-block.cpp diff --git a/clang/lib/CIR/Dialect/Transforms/TargetLowering.cpp b/clang/lib/CIR/Dialect/Transforms/TargetLowering.cpp index aa782aedfda1d..22ffeedc8b3af 100644 --- a/clang/lib/CIR/Dialect/Transforms/TargetLowering.cpp +++ b/clang/lib/CIR/Dialect/Transforms/TargetLowering.cpp @@ -20,6 +20,7 @@ #include "clang/CIR/Dialect/IR/CIRDialect.h" #include "clang/CIR/Dialect/IR/CIRTypes.h" #include "clang/CIR/Dialect/Passes.h" +#include "clang/CIR/Dialect/Transforms/CIRTransformUtils.h" using namespace mlir; using namespace cir; @@ -320,7 +321,11 @@ void TargetLoweringPass::runOnOperation() { mlir::ConversionTarget target(*mod.getContext()); populateTargetLoweringConversionTarget(target, typeConverter); - if (failed(mlir::applyPartialConversion(mod, target, std::move(patterns)))) + llvm::SmallVector<mlir::Operation *> ops; + ops.push_back(mod); + cir::collectUnreachable(mod, ops); + + if (failed(mlir::applyPartialConversion(ops, target, std::move(patterns)))) signalPassFailure(); } diff --git a/clang/test/CIR/CodeGen/target-lowering-dead-block.cpp b/clang/test/CIR/CodeGen/target-lowering-dead-block.cpp new file mode 100644 index 0000000000000..c738e5d1eade6 --- /dev/null +++ b/clang/test/CIR/CodeGen/target-lowering-dead-block.cpp @@ -0,0 +1,34 @@ +// RUN: %clang_cc1 -fcuda-is-device -triple amdgpu -fclangir -emit-cir -mmlir -mlir-print-ir-before=cir-target-lowering %s -o %t.cir 2> %t.pre.cir +// RUN: FileCheck --check-prefix=CIR,CIR-PRE --input-file=%t.pre.cir %s +// RUN: FileCheck --check-prefix=CIR,CIR-POST --input-file=%t.cir %s + +__attribute__((device)) int test(int input) { + int a = input; + if (!input) { + __builtin_trap(); + return a; + } else { + return a; + } +} + +// CIR-LABEL: cir.func {{.*}}@_Z4testi + +// CIR-PRE: %[[RETVAL:.*]] = cir.alloca "__retval" {{.*}} : !cir.ptr<!s32i, lang_address_space(offload_private)> +// CIR-POST: %[[RETVAL:.*]] = cir.alloca "__retval" {{.*}} : !cir.ptr<!s32i, target_address_space(5)> + +// CIR-PRE: %[[A:.*]] = cir.alloca "a" align(4) init : !cir.ptr<!s32i, lang_address_space(offload_private)> +// CIR-POST: %[[A:.*]] = cir.alloca "a" align(4) init : !cir.ptr<!s32i, target_address_space(5)> + +// CIR-POST-NOT: builtin.unrealized_conversion_cast + +// CIR-PRE: %[[ACAST:.*]] = cir.cast address_space %[[A]] : !cir.ptr<!s32i, lang_address_space(offload_private)> -> !cir.ptr<!s32i> +// CIR-POST: %[[ACAST:.*]] = cir.cast address_space %[[A]] : !cir.ptr<!s32i, target_address_space(5)> -> !cir.ptr<!s32i> + +// CIR: cir.trap +// CIR: %[[LOAD:.*]] = cir.load align(4) %[[ACAST]] : !cir.ptr<!s32i>, !s32i +// CIR-PRE-NEXT: cir.store %[[LOAD]], %[[RETVAL]] : !s32i, !cir.ptr<!s32i, lang_address_space(offload_private)> +// CIR-PRE-NEXT: %[[RET:.*]] = cir.load %[[RETVAL]] : !cir.ptr<!s32i, lang_address_space(offload_private)>, !s32i +// CIR-POST-NEXT: cir.store %[[LOAD]], %[[RETVAL]] : !s32i, !cir.ptr<!s32i, target_address_space(5)> +// CIR-POST-NEXT: %[[RET:.*]] = cir.load %[[RETVAL]] : !cir.ptr<!s32i, target_address_space(5)>, !s32i +// CIR-NEXT: cir.return %[[RET]] : !s32i _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
