https://github.com/Luhaocong created https://github.com/llvm/llvm-project/pull/168479
Support CIR codegen for x86 builtins `__builtin_ia32_lzcnt` and `__builtin_ia32_tzcnt`. >From bb6429a1bb11c2794f0a68646f1f97320cdbfcdf Mon Sep 17 00:00:00 2001 From: Haocong Lu <[email protected]> Date: Tue, 18 Nov 2025 11:14:05 +0800 Subject: [PATCH] [CIR] Upstream CIR codegen for `lzcnt` and `tzcnt` x86 builtins Support CIR codegen for x86 builtins `__builtin_ia32_lzcnt` and `__builtin_ia32_tzcnt`. --- clang/lib/CIR/CodeGen/CIRGenBuiltinX86.cpp | 23 ++++++- clang/test/CIR/CodeGen/X86/bmi-builtins.c | 49 +++++++++++++++ clang/test/CIR/CodeGen/X86/lzcnt-builtins.c | 67 +++++++++++++++++++++ 3 files changed, 136 insertions(+), 3 deletions(-) create mode 100644 clang/test/CIR/CodeGen/X86/bmi-builtins.c create mode 100644 clang/test/CIR/CodeGen/X86/lzcnt-builtins.c diff --git a/clang/lib/CIR/CodeGen/CIRGenBuiltinX86.cpp b/clang/lib/CIR/CodeGen/CIRGenBuiltinX86.cpp index ba160373ec77e..8876c95e4942e 100644 --- a/clang/lib/CIR/CodeGen/CIRGenBuiltinX86.cpp +++ b/clang/lib/CIR/CodeGen/CIRGenBuiltinX86.cpp @@ -86,13 +86,30 @@ mlir::Value CIRGenFunction::emitX86BuiltinExpr(unsigned builtinID, return emitIntrinsicCallOp(*this, e, "x86.sse.sfence", voidTy); case X86::BI_mm_prefetch: case X86::BI__rdtsc: - case X86::BI__builtin_ia32_rdtscp: + case X86::BI__builtin_ia32_rdtscp: { + cgm.errorNYI(e->getSourceRange(), + std::string("unimplemented X86 builtin call: ") + + getContext().BuiltinInfo.getName(builtinID)); + return {}; + } case X86::BI__builtin_ia32_lzcnt_u16: case X86::BI__builtin_ia32_lzcnt_u32: - case X86::BI__builtin_ia32_lzcnt_u64: + case X86::BI__builtin_ia32_lzcnt_u64: { + mlir::Value isZeroPoison = + cir::ConstantOp::create(builder, getLoc(e->getExprLoc()), + cir::BoolAttr::get(&getMLIRContext(), false)); + return emitIntrinsicCallOp(*this, e, "ctlz", ops[0].getType(), + mlir::ValueRange{ops[0], isZeroPoison}); + } case X86::BI__builtin_ia32_tzcnt_u16: case X86::BI__builtin_ia32_tzcnt_u32: - case X86::BI__builtin_ia32_tzcnt_u64: + case X86::BI__builtin_ia32_tzcnt_u64: { + mlir::Value isZeroPoison = + cir::ConstantOp::create(builder, getLoc(e->getExprLoc()), + cir::BoolAttr::get(&getMLIRContext(), false)); + return emitIntrinsicCallOp(*this, e, "cttz", ops[0].getType(), + mlir::ValueRange{ops[0], isZeroPoison}); + } case X86::BI__builtin_ia32_undef128: case X86::BI__builtin_ia32_undef256: case X86::BI__builtin_ia32_undef512: diff --git a/clang/test/CIR/CodeGen/X86/bmi-builtins.c b/clang/test/CIR/CodeGen/X86/bmi-builtins.c new file mode 100644 index 0000000000000..1e202ca566ec7 --- /dev/null +++ b/clang/test/CIR/CodeGen/X86/bmi-builtins.c @@ -0,0 +1,49 @@ +// RUN: %clang_cc1 -x c -ffreestanding -triple x86_64-unknown-linux -Wno-implicit-function-declaration -fclangir -emit-cir -o %t.cir %s +// RUN: FileCheck --check-prefix=CIR --input-file=%t.cir %s +// RUN: %clang_cc1 -x c++ -ffreestanding -triple x86_64-unknown-linux -Wno-implicit-function-declaration -fclangir -emit-cir -o %t.cir %s +// RUN: FileCheck --check-prefix=CIR --input-file=%t.cir %s + +// RUN: %clang_cc1 -x c -ffreestanding -triple x86_64-unknown-linux -Wno-implicit-function-declaration -fclangir -emit-llvm -o %t.ll %s +// RUN: FileCheck --check-prefix=LLVM --input-file=%t.ll %s +// RUN: %clang_cc1 -x c++ -ffreestanding -triple x86_64-unknown-linux -Wno-implicit-function-declaration -fclangir -emit-llvm -o %t.ll %s +// RUN: FileCheck --check-prefix=LLVM --input-file=%t.ll %s + +// RUN: %clang_cc1 -x c -ffreestanding -triple=x86_64-unknown-linux -emit-llvm -Wall -Werror %s -o - | FileCheck %s -check-prefix=OGCG +// RUN: %clang_cc1 -x c++ -ffreestanding -triple=x86_64-unknown-linux -emit-llvm -Wall -Werror %s -o - | FileCheck %s -check-prefix=OGCG + +// This test mimics clang/test/CodeGen/X86/bmi-builtins.c, which eventually +// CIR shall be able to support fully. + +#include <immintrin.h> + +unsigned short test__tzcnt_u16(unsigned short __X) { + // CIR-LABEL: __tzcnt_u16 + // CIR: {{%.*}} = cir.call_llvm_intrinsic "cttz" {{%.*}} : (!u16i, !cir.bool) -> !u16i + // LLVM-LABEL: __tzcnt_u16 + // LLVM: i16 @llvm.cttz.i16(i16 %{{.*}}, i1 false) + // OGCG-LABEL: __tzcnt_u16 + // OGCG: i16 @llvm.cttz.i16(i16 %{{.*}}, i1 false) + return __tzcnt_u16(__X); +} + +unsigned int test__tzcnt_u32(unsigned int __X) { + // CIR-LABEL: __tzcnt_u32 + // CIR: {{%.*}} = cir.call_llvm_intrinsic "cttz" {{%.*}} : (!u32i, !cir.bool) -> !u32i + // LLVM-LABEL: __tzcnt_u32 + // LLVM: i32 @llvm.cttz.i32(i32 %{{.*}}, i1 false) + // OGCG-LABEL: __tzcnt_u32 + // OGCG: i32 @llvm.cttz.i32(i32 %{{.*}}, i1 false) + return __tzcnt_u32(__X); +} + +#ifdef __x86_64__ +unsigned long long test__tzcnt_u64(unsigned long long __X) { + // CIR-LABEL: __tzcnt_u64 + // CIR: {{%.*}} = cir.call_llvm_intrinsic "cttz" {{%.*}} : (!u64i, !cir.bool) -> !u64i + // LLVM-LABEL: __tzcnt_u64 + // LLVM: i64 @llvm.cttz.i64(i64 %{{.*}}, i1 false) + // OGCG-LABEL: __tzcnt_u64 + // OGCG: i64 @llvm.cttz.i64(i64 %{{.*}}, i1 false) + return __tzcnt_u64(__X); +} +#endif diff --git a/clang/test/CIR/CodeGen/X86/lzcnt-builtins.c b/clang/test/CIR/CodeGen/X86/lzcnt-builtins.c new file mode 100644 index 0000000000000..a6f4e0440d735 --- /dev/null +++ b/clang/test/CIR/CodeGen/X86/lzcnt-builtins.c @@ -0,0 +1,67 @@ +// RUN: %clang_cc1 -x c -ffreestanding -triple x86_64-unknown-linux -Wno-implicit-function-declaration -fclangir -emit-cir -o %t.cir %s +// RUN: FileCheck --check-prefix=CIR --input-file=%t.cir %s +// RUN: %clang_cc1 -x c++ -ffreestanding -triple x86_64-unknown-linux -Wno-implicit-function-declaration -fclangir -emit-cir -o %t.cir %s +// RUN: FileCheck --check-prefix=CIR --input-file=%t.cir %s + +// RUN: %clang_cc1 -x c -ffreestanding -triple x86_64-unknown-linux -Wno-implicit-function-declaration -fclangir -emit-llvm -o %t.ll %s +// RUN: FileCheck --check-prefix=LLVM --input-file=%t.ll %s +// RUN: %clang_cc1 -x c++ -ffreestanding -triple x86_64-unknown-linux -Wno-implicit-function-declaration -fclangir -emit-llvm -o %t.ll %s +// RUN: FileCheck --check-prefix=LLVM --input-file=%t.ll %s + +// RUN: %clang_cc1 -x c -ffreestanding -triple=x86_64-unknown-linux -emit-llvm -Wall -Werror %s -o - | FileCheck %s -check-prefix=OGCG +// RUN: %clang_cc1 -x c++ -ffreestanding -triple=x86_64-unknown-linux -emit-llvm -Wall -Werror %s -o - | FileCheck %s -check-prefix=OGCG + +// This test mimics clang/test/CodeGen/X86/lzcnt-builtins.c, which eventually +// CIR shall be able to support fully. + +#include <immintrin.h> + +unsigned int test__lzcnt16(unsigned short __X) { + // CIR-LABEL: __lzcnt16 + // CIR: {{%.*}} = cir.call_llvm_intrinsic "ctlz" {{%.*}} : (!u16i, !cir.bool) -> !u16i + // LLVM-LABEL: __lzcnt16 + // LLVM: @llvm.ctlz.i16(i16 %{{.*}}, i1 false) + // OGCG-LABEL: __lzcnt16 + // OGCG: @llvm.ctlz.i16(i16 %{{.*}}, i1 false) + return __lzcnt16(__X); +} + +unsigned int test__lzcnt32(unsigned int __X) { + // CIR-LABEL: __lzcnt32 + // CIR: {{%.*}} = cir.call_llvm_intrinsic "ctlz" {{%.*}} : (!u32i, !cir.bool) -> !u32i + // LLVM-LABEL: __lzcnt32 + // LLVM: @llvm.ctlz.i32(i32 %{{.*}}, i1 false) + // OGCG-LABEL: __lzcnt32 + // OGCG: @llvm.ctlz.i32(i32 %{{.*}}, i1 false) + return __lzcnt32(__X); +} + +unsigned long long test__lzcnt64(unsigned long long __X) { + // CIR-LABEL: __lzcnt64 + // CIR: {{%.*}} = cir.call_llvm_intrinsic "ctlz" {{%.*}} : (!u64i, !cir.bool) -> !u64i + // LLVM-LABEL: __lzcnt64 + // LLVM: @llvm.ctlz.i64(i64 %{{.*}}, i1 false) + // OGCG-LABEL: __lzcnt64 + // OGCG: @llvm.ctlz.i64(i64 %{{.*}}, i1 false) + return __lzcnt64(__X); +} + +unsigned int test__lzcnt_u32(unsigned int __X) { + // CIR-LABEL: _lzcnt_u32 + // CIR: {{%.*}} = cir.call_llvm_intrinsic "ctlz" {{%.*}} : (!u32i, !cir.bool) -> !u32i + // LLVM-LABEL: _lzcnt_u32 + // LLVM: @llvm.ctlz.i32(i32 %{{.*}}, i1 false) + // OGCG-LABEL: _lzcnt_u32 + // OGCG: @llvm.ctlz.i32(i32 %{{.*}}, i1 false) + return _lzcnt_u32(__X); +} + +unsigned long long test__lzcnt_u64(unsigned long long __X) { + // CIR-LABEL: _lzcnt_u64 + // CIR: {{%.*}} = cir.call_llvm_intrinsic "ctlz" {{%.*}} : (!u64i, !cir.bool) -> !u64i + // LLVM-LABEL: _lzcnt_u64 + // LLVM: @llvm.ctlz.i64(i64 %{{.*}}, i1 false) + // OGCG-LABEL: _lzcnt_u64 + // OGCG: @llvm.ctlz.i64(i64 %{{.*}}, i1 false) + return _lzcnt_u64(__X); +} _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
