https://github.com/kimsh02 created https://github.com/llvm/llvm-project/pull/164387
Fix #163886 >From 760e039d06efed1b3459e48b3946be0bbab934bc Mon Sep 17 00:00:00 2001 From: kimsh02 <[email protected]> Date: Tue, 21 Oct 2025 03:26:03 -0700 Subject: [PATCH] [CIR] Upstream handling for __builtin_prefetch --- clang/include/clang/CIR/Dialect/IR/CIROps.td | 33 +++++++++++++++++++ clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp | 21 ++++++++++++ .../CIR/Lowering/DirectToLLVM/LowerToLLVM.cpp | 9 +++++ clang/test/CIR/CodeGen/builtin_prefetech.c | 20 +++++++++++ 4 files changed, 83 insertions(+) create mode 100644 clang/test/CIR/CodeGen/builtin_prefetech.c diff --git a/clang/include/clang/CIR/Dialect/IR/CIROps.td b/clang/include/clang/CIR/Dialect/IR/CIROps.td index e0163a4fecd5f..43abdc8f7bc0b 100644 --- a/clang/include/clang/CIR/Dialect/IR/CIROps.td +++ b/clang/include/clang/CIR/Dialect/IR/CIROps.td @@ -4049,6 +4049,39 @@ def CIR_ExpectOp : CIR_Op<"expect", [ }]; } +//===----------------------------------------------------------------------===// +// PrefetchOp +//===----------------------------------------------------------------------===// + +def CIR_PrefetchOp : CIR_Op<"prefetch"> { + let summary = "prefetch operation"; + let description = [{ + The `cir.prefetch` op prefetches data from the memmory address. + + ```mlir + cir.prefetch(%0 : !cir.ptr<!void>) locality(1) write + ``` + + This opcode has the three attributes: + 1. The $locality is a temporal locality specifier + ranging from (0) - no locality, to (3) - extremely local keep in cache. + 2. The $isWrite is the specifier determining if the prefetch is prepaired + for a 'read' or 'write'. + If $isWrite doesn't specified it means that prefetch is prepared for 'read'. + }]; + + let arguments = (ins CIR_VoidPtrType:$addr, + ConfinedAttr<I32Attr, [IntMinValue<0>, IntMaxValue<3>]>:$locality, + UnitAttr:$isWrite); + + let assemblyFormat = [{ + `(` $addr `:` qualified(type($addr)) `)` + `locality``(` $locality `)` + (`write` $isWrite^) : (`read`)? + attr-dict + }]; +} + //===----------------------------------------------------------------------===// // PtrDiffOp //===----------------------------------------------------------------------===// diff --git a/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp b/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp index ea31871806bd7..2571a402f9676 100644 --- a/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp +++ b/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp @@ -454,6 +454,27 @@ RValue CIRGenFunction::emitBuiltinExpr(const GlobalDecl &gd, unsigned builtinID, assert(!cir::MissingFeatures::coroSizeBuiltinCall()); return getUndefRValue(e->getType()); } + case Builtin::BI__builtin_prefetch: { + auto evaluateOperandAsInt = [&](const Expr *arg) { + Expr::EvalResult res; + [[maybe_unused]] bool evalSucceed = + arg->EvaluateAsInt(res, cgm.getASTContext()); + assert(evalSucceed && "expression should be able to evaluate as int"); + return res.Val.getInt().getZExtValue(); + }; + + bool isWrite = false; + if (e->getNumArgs() > 1) + isWrite = evaluateOperandAsInt(e->getArg(1)); + + int locality = 0; + if (e->getNumArgs() > 2) + locality = evaluateOperandAsInt(e->getArg(2)); + + mlir::Value address = emitScalarExpr(e->getArg(0)); + cir::PrefetchOp::create(builder, loc, address, locality, isWrite); + return RValue::get(nullptr); + } } // If this is an alias for a lib function (e.g. __builtin_sin), emit diff --git a/clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.cpp b/clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.cpp index 0243bf120f396..47f9d79b30655 100644 --- a/clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.cpp +++ b/clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.cpp @@ -1507,6 +1507,15 @@ static uint64_t getTypeSize(mlir::Type type, mlir::Operation &op) { return llvm::divideCeil(layout.getTypeSizeInBits(type), 8); } +mlir::LogicalResult CIRToLLVMPrefetchOpLowering::matchAndRewrite( + cir::PrefetchOp op, OpAdaptor adaptor, + mlir::ConversionPatternRewriter &rewriter) const { + rewriter.replaceOpWithNewOp<mlir::LLVM::Prefetch>( + op, adaptor.getAddr(), adaptor.getIsWrite(), adaptor.getLocality(), + /*DataCache*/ 1); + return mlir::success(); +} + mlir::LogicalResult CIRToLLVMPtrDiffOpLowering::matchAndRewrite( cir::PtrDiffOp op, OpAdaptor adaptor, mlir::ConversionPatternRewriter &rewriter) const { diff --git a/clang/test/CIR/CodeGen/builtin_prefetech.c b/clang/test/CIR/CodeGen/builtin_prefetech.c new file mode 100644 index 0000000000000..343d9a808ad68 --- /dev/null +++ b/clang/test/CIR/CodeGen/builtin_prefetech.c @@ -0,0 +1,20 @@ +// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-cir %s -o - | FileCheck %s -check-prefix=CIR +// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fclangir -emit-llvm %s -o - | FileCheck %s -check-prefix=LLVM + +void foo(void *a) { + __builtin_prefetch(a, 1, 1); +} + +// CIR: cir.func dso_local @foo(%arg0: !cir.ptr<!void> loc({{.*}})) +// CIR: [[PTR_ALLOC:%.*]] = cir.alloca !cir.ptr<!void>, !cir.ptr<!cir.ptr<!void>>, ["a", init] {alignment = 8 : i64} +// CIR: cir.store %arg0, [[PTR_ALLOC]] : !cir.ptr<!void>, !cir.ptr<!cir.ptr<!void>> +// CIR: [[PTR:%.*]] = cir.load{{.*}} [[PTR_ALLOC]] : !cir.ptr<!cir.ptr<!void>>, !cir.ptr<!void> +// CIR: cir.prefetch([[PTR]] : !cir.ptr<!void>) locality(1) write +// CIR: cir.return + +// LLVM: define dso_local void @foo(ptr [[ARG0:%.*]]) +// LLVM: [[PTR_ALLOC:%.*]] = alloca ptr, i64 1 +// LLVM: store ptr [[ARG0]], ptr [[PTR_ALLOC]] +// LLVM: [[PTR:%.*]] = load ptr, ptr [[PTR_ALLOC]] +// LLVM: call void @llvm.prefetch.p0(ptr [[PTR]], i32 1, i32 1, i32 1) +// LLVM: ret void _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
