[CIR] Upstream __real__ for ComplexType (llvm#144261)

AmrDeveloper · Anthony Tran · commit ff33f69e2a8e · 2025-06-26T12:46:06.000-07:00
This change adds support for __real__ for ComplexType llvm#141365
diff --git a/clang/include/clang/CIR/Dialect/IR/CIROps.td b/clang/include/clang/CIR/Dialect/IR/CIROps.td
@@ -2371,6 +2371,35 @@ def ComplexCreateOp : CIR_Op<"complex.create", [Pure, SameTypeOperands]> {
   let hasFolder = 1;
 }
 
+//===----------------------------------------------------------------------===//
+// ComplexRealOp
+//===----------------------------------------------------------------------===//
+
+def ComplexRealOp : CIR_Op<"complex.real", [Pure]> {
+  let summary = "Extract the real part of a complex value";
+  let description = [{
+    `cir.complex.real` operation takes an operand of `!cir.complex` type and
+    yields the real part of it.
+
+    Example:
+
+    ```mlir
+    %1 = cir.complex.real %0 : !cir.complex<!cir.float> -> !cir.float
+    ```
+  }];
+
+  let results = (outs CIR_AnyIntOrFloatType:$result);
+  let arguments = (ins CIR_ComplexType:$operand);
+
+  let assemblyFormat = [{
+    $operand `:` qualified(type($operand)) `->` qualified(type($result))
+    attr-dict
+  }];
+
+  let hasVerifier = 1;
+  let hasFolder = 1;
+}
+
 //===----------------------------------------------------------------------===//
 // Assume Operations
 //===----------------------------------------------------------------------===//
diff --git a/clang/lib/CIR/CodeGen/CIRGenBuilder.h b/clang/lib/CIR/CodeGen/CIRGenBuilder.h
@@ -366,6 +366,11 @@ class CIRGenBuilderTy : public cir::CIRBaseBuilderTy {
     return create<cir::ComplexCreateOp>(loc, resultComplexTy, real, imag);
   }
 
+  mlir::Value createComplexReal(mlir::Location loc, mlir::Value operand) {
+    auto operandTy = mlir::cast<cir::ComplexType>(operand.getType());
+    return create<cir::ComplexRealOp>(loc, operandTy.getElementType(), operand);
+  }
+
   /// Create a cir.ptr_stride operation to get access to an array element.
   /// \p idx is the index of the element to access, \p shouldDecay is true if
   /// the result should decay to a pointer to the element type.
diff --git a/clang/lib/CIR/CodeGen/CIRGenExprScalar.cpp b/clang/lib/CIR/CodeGen/CIRGenExprScalar.cpp
@@ -603,6 +603,8 @@ class ScalarExprEmitter : public StmtVisitor<ScalarExprEmitter, mlir::Value> {
 
   mlir::Value VisitUnaryLNot(const UnaryOperator *e);
 
+  mlir::Value VisitUnaryReal(const UnaryOperator *e);
+
   mlir::Value VisitCXXThisExpr(CXXThisExpr *te) { return cgf.loadCXXThis(); }
 
   /// Emit a conversion from the specified type to the specified destination
@@ -1891,6 +1893,27 @@ mlir::Value ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *e) {
   return maybePromoteBoolResult(boolVal, cgf.convertType(e->getType()));
 }
 
+mlir::Value ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *e) {
+  // TODO(cir): handle scalar promotion.
+  Expr *op = e->getSubExpr();
+  if (op->getType()->isAnyComplexType()) {
+    // If it's an l-value, load through the appropriate subobject l-value.
+    // Note that we have to ask `e` because `op` might be an l-value that
+    // this won't work for, e.g. an Obj-C property.
+    if (e->isGLValue()) {
+      mlir::Location loc = cgf.getLoc(e->getExprLoc());
+      mlir::Value complex = cgf.emitComplexExpr(op);
+      return cgf.builder.createComplexReal(loc, complex);
+    }
+
+    // Otherwise, calculate and project.
+    cgf.cgm.errorNYI(e->getSourceRange(),
+                     "VisitUnaryReal calculate and project");
+  }
+
+  return Visit(op);
+}
+
 /// Return the size or alignment of the type of argument of the sizeof
 /// expression as an integer.
 mlir::Value ScalarExprEmitter::VisitUnaryExprOrTypeTraitExpr(
diff --git a/clang/lib/CIR/Dialect/IR/CIRDialect.cpp b/clang/lib/CIR/Dialect/IR/CIRDialect.cpp
@@ -1914,6 +1914,24 @@ OpFoldResult cir::ComplexCreateOp::fold(FoldAdaptor adaptor) {
   return cir::ConstComplexAttr::get(realAttr, imagAttr);
 }
 
+//===----------------------------------------------------------------------===//
+// ComplexRealOp
+//===----------------------------------------------------------------------===//
+
+LogicalResult cir::ComplexRealOp::verify() {
+  if (getType() != getOperand().getType().getElementType()) {
+    emitOpError() << ": result type does not match operand type";
+    return failure();
+  }
+  return success();
+}
+
+OpFoldResult cir::ComplexRealOp::fold(FoldAdaptor adaptor) {
+  auto complex =
+      mlir::cast_if_present<cir::ConstComplexAttr>(adaptor.getOperand());
+  return complex ? complex.getReal() : nullptr;
+}
+
 //===----------------------------------------------------------------------===//
 // TableGen'd op method definitions
 //===----------------------------------------------------------------------===//
diff --git a/clang/lib/CIR/Dialect/Transforms/CIRCanonicalize.cpp b/clang/lib/CIR/Dialect/Transforms/CIRCanonicalize.cpp
@@ -141,8 +141,8 @@ void CIRCanonicalizePass::runOnOperation() {
     // Many operations are here to perform a manual `fold` in
     // applyOpPatternsGreedily.
     if (isa<BrOp, BrCondOp, CastOp, ScopeOp, SwitchOp, SelectOp, UnaryOp,
-            ComplexCreateOp, VecCmpOp, VecCreateOp, VecExtractOp, VecShuffleOp,
-            VecShuffleDynamicOp, VecTernaryOp>(op))
+            ComplexCreateOp, ComplexRealOp, VecCmpOp, VecCreateOp, VecExtractOp,
+            VecShuffleOp, VecShuffleDynamicOp, VecTernaryOp>(op))
       ops.push_back(op);
   });
 
diff --git a/clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.cpp b/clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.cpp
@@ -1903,7 +1903,8 @@ void ConvertCIRToLLVMPass::runOnOperation() {
                CIRToLLVMVecShuffleOpLowering,
                CIRToLLVMVecShuffleDynamicOpLowering,
                CIRToLLVMVecTernaryOpLowering,
-               CIRToLLVMComplexCreateOpLowering
+               CIRToLLVMComplexCreateOpLowering,
+               CIRToLLVMComplexRealOpLowering
       // clang-format on
       >(converter, patterns.getContext());
 
@@ -2207,6 +2208,15 @@ mlir::LogicalResult CIRToLLVMComplexCreateOpLowering::matchAndRewrite(
   return mlir::success();
 }
 
+mlir::LogicalResult CIRToLLVMComplexRealOpLowering::matchAndRewrite(
+    cir::ComplexRealOp op, OpAdaptor adaptor,
+    mlir::ConversionPatternRewriter &rewriter) const {
+  mlir::Type resultLLVMTy = getTypeConverter()->convertType(op.getType());
+  rewriter.replaceOpWithNewOp<mlir::LLVM::ExtractValueOp>(
+      op, resultLLVMTy, adaptor.getOperand(), llvm::ArrayRef<std::int64_t>{0});
+  return mlir::success();
+}
+
 std::unique_ptr<mlir::Pass> createConvertCIRToLLVMPass() {
   return std::make_unique<ConvertCIRToLLVMPass>();
 }
diff --git a/clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.h b/clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.h
@@ -443,6 +443,16 @@ class CIRToLLVMComplexCreateOpLowering
                   mlir::ConversionPatternRewriter &) const override;
 };
 
+class CIRToLLVMComplexRealOpLowering
+    : public mlir::OpConversionPattern<cir::ComplexRealOp> {
+public:
+  using mlir::OpConversionPattern<cir::ComplexRealOp>::OpConversionPattern;
+
+  mlir::LogicalResult
+  matchAndRewrite(cir::ComplexRealOp op, OpAdaptor,
+                  mlir::ConversionPatternRewriter &) const override;
+};
+
 } // namespace direct
 } // namespace cir
 
diff --git a/clang/test/CIR/CodeGen/complex.cpp b/clang/test/CIR/CodeGen/complex.cpp
@@ -216,6 +216,30 @@ void foo9(double a, double b) {
 // OGCG: store double %[[TMP_A]], ptr %[[C_REAL_PTR]], align 8
 // OGCG: store double %[[TMP_B]], ptr %[[C_IMAG_PTR]], align 8
 
+void foo13() {
+  double _Complex c;
+  double real = __real__ c;
+}
+
+// CIR: %[[COMPLEX:.*]] = cir.alloca !cir.complex<!cir.double>, !cir.ptr<!cir.complex<!cir.double>>, ["c"]
+// CIR: %[[INIT:.*]] = cir.alloca !cir.double, !cir.ptr<!cir.double>, ["real", init]
+// CIR: %[[TMP:.*]] = cir.load{{.*}} %[[COMPLEX]] : !cir.ptr<!cir.complex<!cir.double>>, !cir.complex<!cir.double>
+// CIR: %[[REAL:.*]] = cir.complex.real %[[TMP]] : !cir.complex<!cir.double> -> !cir.double
+// CIR: cir.store{{.*}} %[[REAL]], %[[INIT]] : !cir.double, !cir.ptr<!cir.double>
+
+// LLVM: %[[COMPLEX:.*]] = alloca { double, double }, i64 1, align 8
+// LLVM: %[[INIT:.*]] = alloca double, i64 1, align 8
+// LLVM: %[[TMP:.*]] = load { double, double }, ptr %[[COMPLEX]], align 8
+// LLVM: %[[REAL:.*]] = extractvalue { double, double } %[[TMP]], 0
+// LLVM: store double %[[REAL]], ptr %[[INIT]], align 8
+
+// OGCG: %[[COMPLEX:.*]] = alloca { double, double }, align 8
+// OGCG: %[[INIT:.*]] = alloca double, align 8
+// OGCG: %[[REAL:.*]] = getelementptr inbounds nuw { double, double }, ptr %[[COMPLEX]], i32 0, i32 0
+// OGCG: %[[TMP:.*]] = load double, ptr %[[REAL]], align 8
+// OGCG: store double %[[TMP]], ptr %[[INIT]], align 8
+
+
 void foo14() {
   int _Complex c = 2i;
 }
@@ -256,3 +280,36 @@ void foo15() {
 // OGCG: %[[B_IMAG_PTR:.*]] = getelementptr inbounds nuw { i32, i32 }, ptr %[[COMPLEX_B]], i32 0, i32 1
 // OGCG: store i32 %[[A_REAL]], ptr %[[B_REAL_PTR]], align 4
 // OGCG: store i32 %[[A_IMAG]], ptr %[[B_IMAG_PTR]], align 4
+
+int foo17(int _Complex a, int _Complex b) {
+  return __real__ a + __real__ b;
+}
+
+// CIR: %[[RET:.*]] = cir.alloca !s32i, !cir.ptr<!s32i>, ["__retval"]
+// CIR: %[[COMPLEX_A:.*]] = cir.load{{.*}} {{.*}} : !cir.ptr<!cir.complex<!s32i>>, !cir.complex<!s32i>
+// CIR: %[[A_REAL:.*]] = cir.complex.real %[[COMPLEX_A]] : !cir.complex<!s32i> -> !s32i
+// CIR: %[[COMPLEX_B:.*]] = cir.load{{.*}} {{.*}} : !cir.ptr<!cir.complex<!s32i>>, !cir.complex<!s32i>
+// CIR: %[[B_REAL:.*]] = cir.complex.real %[[COMPLEX_B]] : !cir.complex<!s32i> -> !s32i
+// CIR: %[[ADD:.*]] = cir.binop(add, %[[A_REAL]], %[[B_REAL]]) nsw : !s32i
+// CIR: cir.store %[[ADD]], %[[RET]] : !s32i, !cir.ptr<!s32i>
+// CIR: %[[TMP:.*]] = cir.load %[[RET]] : !cir.ptr<!s32i>, !s32i
+// CIR: cir.return %[[TMP]] : !s32i
+
+// LLVM: %[[RET:.*]] = alloca i32, i64 1, align 4
+// LLVM: %[[COMPLEX_A:.*]] = load { i32, i32 }, ptr {{.*}}, align 4
+// LLVM: %[[A_REAL:.*]] = extractvalue { i32, i32 } %[[COMPLEX_A]], 0
+// LLVM: %[[COMPLEX_B:.*]] = load { i32, i32 }, ptr {{.*}}, align 4
+// LLVM: %[[B_REAL:.*]] = extractvalue { i32, i32 } %[[COMPLEX_B]], 0
+// LLVM: %[[ADD:.*]] = add nsw i32 %[[A_REAL]], %[[B_REAL]]
+// LLVM: store i32 %[[ADD]], ptr %[[RET]], align 4
+// LLVM: %[[TMP:.*]] = load i32, ptr %[[RET]], align 4
+// LLVM: ret i32 %[[TMP]]
+
+// OGCG: %[[COMPLEX_A:.*]] = alloca { i32, i32 }, align 4
+// OGCG: %[[COMPLEX_B:.*]] = alloca { i32, i32 }, align 4
+// OGCG: %[[A_REAL:.*]] = getelementptr inbounds nuw { i32, i32 }, ptr %[[COMPLEX_A]], i32 0, i32 0
+// OGCG: %[[TMP_A:.*]] = load i32, ptr %[[A_REAL]], align 4
+// OGCG: %[[B_REAL:.*]] = getelementptr inbounds nuw { i32, i32 }, ptr %[[COMPLEX_B]], i32 0, i32 0
+// OGCG: %[[TMP_B:.*]] = load i32, ptr %[[B_REAL]], align 4
+// OGCG: %[[ADD:.*]] = add nsw i32 %[[TMP_A]], %[[TMP_B]]
+// OGCG: ret i32 %[[ADD]]
diff --git a/clang/test/CIR/IR/invalid-complex.cir b/clang/test/CIR/IR/invalid-complex.cir
@@ -21,3 +21,15 @@ module {
 cir.global external @ci2 = #cir.const_complex<#cir.int<1> : !s32i, #cir.int<2> : !s64i> : !cir.complex<!s32i>
 
 }
+
+// -----
+
+module {
+  cir.func @complex_real_invalid_result_type() -> !cir.double {
+    %0 = cir.alloca !cir.complex<!cir.double>, !cir.ptr<!cir.complex<!cir.double>>, ["c"]
+    %2 = cir.load align(8) %0 : !cir.ptr<!cir.complex<!cir.double>>, !cir.complex<!cir.double>
+    // expected-error @below {{result type does not match operand type}}
+    %3 = cir.complex.real %2 : !cir.complex<!cir.double> -> !cir.float
+    cir.return
+  }
+}
diff --git a/clang/test/CIR/Transforms/complex-real-fold.cir b/clang/test/CIR/Transforms/complex-real-fold.cir
@@ -0,0 +1,23 @@
+// RUN: cir-opt %s -cir-canonicalize -o - | FileCheck %s
+
+!s32i = !cir.int<s, 32>
+
+module {
+  cir.func @fold_complex_real_test() -> !s32i {
+    %0 = cir.alloca !s32i, !cir.ptr<!s32i>, ["__retval"]
+    %2 = cir.const #cir.const_complex<#cir.int<1> : !s32i, #cir.int<2> : !s32i> : !cir.complex<!s32i>
+    %4 = cir.complex.real %2 : !cir.complex<!s32i> -> !s32i
+    cir.store %4, %0 : !s32i, !cir.ptr<!s32i>
+    %5 = cir.load %0 : !cir.ptr<!s32i>, !s32i
+    cir.return %5 : !s32i
+  }
+
+  // CHECK: cir.func @fold_complex_real_test() -> !s32i {
+  // CHECK:   %[[RET:.*]] = cir.alloca !s32i, !cir.ptr<!s32i>, ["__retval"]
+  // CHECK:   %[[REAL:.*]] = cir.const #cir.int<1> : !s32i
+  // CHECK:   cir.store %[[REAL]], %[[RET]] : !s32i, !cir.ptr<!s32i>
+  // CHECK:   %[[TMP:.]] = cir.load %[[RET]] : !cir.ptr<!s32i>, !s32i
+  // CHECK:   cir.return %[[TMP]] : !s32i
+  // CHECK: }
+
+}
