[Flang] Change complex divide lowering

Currently complex division is lowered to a fir.divc operation and the
fir.divc is later converted to a sequence of llvm operations to perform
complex division, however this causes issues for extreme values when
the calculations overflow.

This patch changes the lowering of complex division to use the Intrinsic
Call functionality to lower into library calls (for single, double,
extended and quad precisions) or an MLIR complex dialect division operation
(for half and bfloat precisions).

 A new wrapper function `genLibSplitComplexArgsCall` is written to handle
 the case of the arguments of the Complex Library calls being split to
its real and imaginary real components.

Note 1: If the Complex To Standard conversion of division operation
matures then we can use it for all precisions. Currently it has the
same issues as the conversion of fir.divc.
Note 2: A previous patch (D145808) did the same but during conversion of
the fir.divc operation. But using function calls at that stage leads to
ABI issues since the conversion to LLVM is not aware of the complex target
rewrite.
Note 3: If the patch is accepted, fir.divc can be removed from FIR. We
can use the complex.div operation where any transformation is required.

Reviewed By: vzakhari, PeteSteinfeld, DavidTruby, jeanPerier

Differential Revision: https://reviews.llvm.org/D149546

diff --git a/flang/include/flang/Optimizer/Builder/IntrinsicCall.h b/flang/include/flang/Optimizer/Builder/IntrinsicCall.h
index 2cc797f..0d32976 100644 (file)
--- a/flang/include/flang/Optimizer/Builder/IntrinsicCall.h
+++ b/flang/include/flang/Optimizer/Builder/IntrinsicCall.h
@@ -98,6 +98,11 @@ mlir::Value genMax(fir::FirOpBuilder &, mlir::Location,
 mlir::Value genMin(fir::FirOpBuilder &, mlir::Location,
                    llvm::ArrayRef<mlir::Value> args);
 
+/// Generate Complex divide with the given expected
+/// result type.
+mlir::Value genDivC(fir::FirOpBuilder &builder, mlir::Location loc,
+                    mlir::Type resultType, mlir::Value x, mlir::Value y);
+
 /// Generate power function x**y with the given expected
 /// result type.
 mlir::Value genPow(fir::FirOpBuilder &, mlir::Location, mlir::Type resultType,

diff --git a/flang/lib/Lower/ConvertExpr.cpp b/flang/lib/Lower/ConvertExpr.cpp
index dead3c5..2534f4e 100644 (file)
--- a/flang/lib/Lower/ConvertExpr.cpp
+++ b/flang/lib/Lower/ConvertExpr.cpp
@@ -1080,7 +1080,16 @@ public:
   GENBIN(Multiply, Complex, fir::MulcOp)
   GENBIN(Divide, Integer, mlir::arith::DivSIOp)
   GENBIN(Divide, Real, mlir::arith::DivFOp)
-  GENBIN(Divide, Complex, fir::DivcOp)
+
+  template <int KIND>
+  ExtValue genval(const Fortran::evaluate::Divide<Fortran::evaluate::Type<
+                      Fortran::common::TypeCategory::Complex, KIND>> &op) {
+    mlir::Type ty =
+        converter.genType(Fortran::common::TypeCategory::Complex, KIND);
+    mlir::Value lhs = genunbox(op.left());
+    mlir::Value rhs = genunbox(op.right());
+    return fir::genDivC(builder, getLoc(), ty, lhs, rhs);
+  }
 
   template <Fortran::common::TypeCategory TC, int KIND>
   ExtValue genval(
@@ -5082,7 +5091,21 @@ private:
   GENBIN(Multiply, Complex, fir::MulcOp)
   GENBIN(Divide, Integer, mlir::arith::DivSIOp)
   GENBIN(Divide, Real, mlir::arith::DivFOp)
-  GENBIN(Divide, Complex, fir::DivcOp)
+
+  template <int KIND>
+  CC genarr(const Fortran::evaluate::Divide<Fortran::evaluate::Type<
+                Fortran::common::TypeCategory::Complex, KIND>> &x) {
+    mlir::Location loc = getLoc();
+    mlir::Type ty =
+        converter.genType(Fortran::common::TypeCategory::Complex, KIND);
+    auto lf = genarr(x.left());
+    auto rf = genarr(x.right());
+    return [=](IterSpace iters) -> ExtValue {
+      mlir::Value lhs = fir::getBase(lf(iters));
+      mlir::Value rhs = fir::getBase(rf(iters));
+      return fir::genDivC(builder, loc, ty, lhs, rhs);
+    };
+  }
 
   template <Fortran::common::TypeCategory TC, int KIND>
   CC genarr(

diff --git a/flang/lib/Lower/ConvertExprToHLFIR.cpp b/flang/lib/Lower/ConvertExprToHLFIR.cpp
index 22425cc..bfa84be 100644 (file)
--- a/flang/lib/Lower/ConvertExprToHLFIR.cpp
+++ b/flang/lib/Lower/ConvertExprToHLFIR.cpp
@@ -948,7 +948,22 @@ GENBIN(Multiply, Real, mlir::arith::MulFOp)
 GENBIN(Multiply, Complex, fir::MulcOp)
 GENBIN(Divide, Integer, mlir::arith::DivSIOp)
 GENBIN(Divide, Real, mlir::arith::DivFOp)
-GENBIN(Divide, Complex, fir::DivcOp)
+
+template <int KIND>
+struct BinaryOp<Fortran::evaluate::Divide<
+    Fortran::evaluate::Type<Fortran::common::TypeCategory::Complex, KIND>>> {
+  using Op = Fortran::evaluate::Divide<
+      Fortran::evaluate::Type<Fortran::common::TypeCategory::Complex, KIND>>;
+  static hlfir::EntityWithAttributes gen(mlir::Location loc,
+                                         fir::FirOpBuilder &builder, const Op &,
+                                         hlfir::Entity lhs, hlfir::Entity rhs) {
+    mlir::Type ty = Fortran::lower::getFIRType(
+        builder.getContext(), Fortran::common::TypeCategory::Complex, KIND,
+        /*params=*/std::nullopt);
+    return hlfir::EntityWithAttributes{
+        fir::genDivC(builder, loc, ty, lhs, rhs)};
+  }
+};
 
 template <Fortran::common::TypeCategory TC, int KIND>
 struct BinaryOp<Fortran::evaluate::Power<Fortran::evaluate::Type<TC, KIND>>> {

diff --git a/flang/lib/Optimizer/Builder/IntrinsicCall.cpp b/flang/lib/Optimizer/Builder/IntrinsicCall.cpp
index d877be0..dee08c7 100644 (file)
--- a/flang/lib/Optimizer/Builder/IntrinsicCall.cpp
+++ b/flang/lib/Optimizer/Builder/IntrinsicCall.cpp
@@ -1184,6 +1184,54 @@ static mlir::Value genLibCall(fir::FirOpBuilder &builder, mlir::Location loc,
   return libCall.getResult(0);
 }
 
+static mlir::Value genLibSplitComplexArgsCall(
+    fir::FirOpBuilder &builder, mlir::Location loc, llvm::StringRef libFuncName,
+    mlir::FunctionType libFuncType, llvm::ArrayRef<mlir::Value> args) {
+  assert(args.size() == 2 && "Incorrect #args to genLibSplitComplexArgsCall");
+
+  auto getSplitComplexArgsType = [&builder, &args]() -> mlir::FunctionType {
+    mlir::Type ctype = args[0].getType();
+    auto fKind = ctype.cast<fir::ComplexType>().getFKind();
+    mlir::Type ftype;
+
+    if (fKind == 2)
+      ftype = builder.getF16Type();
+    else if (fKind == 3)
+      ftype = builder.getBF16Type();
+    else if (fKind == 4)
+      ftype = builder.getF32Type();
+    else if (fKind == 8)
+      ftype = builder.getF64Type();
+    else if (fKind == 10)
+      ftype = builder.getF80Type();
+    else if (fKind == 16)
+      ftype = builder.getF128Type();
+    else
+      assert(0 && "Unsupported Complex Type");
+
+    return builder.getFunctionType({ftype, ftype, ftype, ftype}, {ctype});
+  };
+
+  llvm::SmallVector<mlir::Value, 4> splitArgs;
+  mlir::Value cplx1 = args[0];
+  auto real1 = fir::factory::Complex{builder, loc}.extractComplexPart(
+      cplx1, /*isImagPart=*/false);
+  splitArgs.push_back(real1);
+  auto imag1 = fir::factory::Complex{builder, loc}.extractComplexPart(
+      cplx1, /*isImagPart=*/true);
+  splitArgs.push_back(imag1);
+  mlir::Value cplx2 = args[1];
+  auto real2 = fir::factory::Complex{builder, loc}.extractComplexPart(
+      cplx2, /*isImagPart=*/false);
+  splitArgs.push_back(real2);
+  auto imag2 = fir::factory::Complex{builder, loc}.extractComplexPart(
+      cplx2, /*isImagPart=*/true);
+  splitArgs.push_back(imag2);
+
+  return genLibCall(builder, loc, libFuncName, getSplitComplexArgsType(),
+                    splitArgs);
+}
+
 template <typename T>
 static mlir::Value genMathOp(fir::FirOpBuilder &builder, mlir::Location loc,
                              llvm::StringRef mathLibFuncName,
@@ -1345,6 +1393,22 @@ static constexpr MathOperation mathOperations[] = {
     {"cosh", "cosh", genF64F64FuncType, genLibCall},
     {"cosh", "ccoshf", genComplexComplexFuncType<4>, genLibCall},
     {"cosh", "ccosh", genComplexComplexFuncType<8>, genLibCall},
+    {"divc",
+     {},
+     genComplexComplexComplexFuncType<2>,
+     genComplexMathOp<mlir::complex::DivOp>},
+    {"divc",
+     {},
+     genComplexComplexComplexFuncType<3>,
+     genComplexMathOp<mlir::complex::DivOp>},
+    {"divc", "__divsc3", genComplexComplexComplexFuncType<4>,
+     genLibSplitComplexArgsCall},
+    {"divc", "__divdc3", genComplexComplexComplexFuncType<8>,
+     genLibSplitComplexArgsCall},
+    {"divc", "__divxc3", genComplexComplexComplexFuncType<10>,
+     genLibSplitComplexArgsCall},
+    {"divc", "__divtc3", genComplexComplexComplexFuncType<16>,
+     genLibSplitComplexArgsCall},
     {"erf", "erff", genF32F32FuncType, genMathOp<mlir::math::ErfOp>},
     {"erf", "erf", genF64F64FuncType, genMathOp<mlir::math::ErfOp>},
     {"erfc", "erfcf", genF32F32FuncType, genLibCall},
@@ -5661,6 +5725,11 @@ mlir::Value fir::genMin(fir::FirOpBuilder &builder, mlir::Location loc,
                                                               args);
 }
 
+mlir::Value fir::genDivC(fir::FirOpBuilder &builder, mlir::Location loc,
+                         mlir::Type type, mlir::Value x, mlir::Value y) {
+  return IntrinsicLibrary{builder, loc}.genRuntimeCall("divc", type, {x, y});
+}
+
 mlir::Value fir::genPow(fir::FirOpBuilder &builder, mlir::Location loc,
                         mlir::Type type, mlir::Value x, mlir::Value y) {
   // TODO: since there is no libm version of pow with integer exponent,

diff --git a/flang/test/Lower/HLFIR/binary-ops.f90 b/flang/test/Lower/HLFIR/binary-ops.f90
index 8e5dced..4b5b1a6 100644 (file)
--- a/flang/test/Lower/HLFIR/binary-ops.f90
+++ b/flang/test/Lower/HLFIR/binary-ops.f90
@@ -131,8 +131,11 @@ end subroutine
 ! CHECK:  %[[VAL_5:.*]]:2 = hlfir.declare %{{.*}}z"} : (!fir.ref<!fir.complex<4>>) -> (!fir.ref<!fir.complex<4>>, !fir.ref<!fir.complex<4>>)
 ! CHECK:  %[[VAL_6:.*]] = fir.load %[[VAL_4]]#0 : !fir.ref<!fir.complex<4>>
 ! CHECK:  %[[VAL_7:.*]] = fir.load %[[VAL_5]]#0 : !fir.ref<!fir.complex<4>>
-! CHECK:  %[[VAL_8:.*]] = fir.divc %[[VAL_6]], %[[VAL_7]] : !fir.complex<4>
-
+! CHECK:  %[[VAL_8:.*]] = fir.extract_value %[[VAL_6]], [0 : index] : (!fir.complex<4>) -> f32
+! CHECK:  %[[VAL_9:.*]] = fir.extract_value %[[VAL_6]], [1 : index] : (!fir.complex<4>) -> f32
+! CHECK:  %[[VAL_10:.*]] = fir.extract_value %[[VAL_7]], [0 : index] : (!fir.complex<4>) -> f32
+! CHECK:  %[[VAL_11:.*]] = fir.extract_value %[[VAL_7]], [1 : index] : (!fir.complex<4>) -> f32
+! CHECK:  %[[VAL_12:.*]] = fir.call @__divsc3(%[[VAL_8]], %[[VAL_9]], %[[VAL_10]], %[[VAL_11]]) fastmath<contract> : (f32, f32, f32, f32) -> !fir.complex<4>
 
 subroutine int_power(x, y, z)
   integer :: x, y, z

diff --git a/flang/test/Lower/assignment.f90 b/flang/test/Lower/assignment.f90
index 8e836ce..9b5039e 100644 (file)
--- a/flang/test/Lower/assignment.f90
+++ b/flang/test/Lower/assignment.f90
@@ -251,7 +251,11 @@ end
 ! CHECK:         %[[FCTRES:.*]] = fir.alloca !fir.complex<4>
 ! CHECK:         %[[A_VAL:.*]] = fir.load %[[A]] : !fir.ref<!fir.complex<4>>
 ! CHECK:         %[[B_VAL:.*]] = fir.load %[[B]] : !fir.ref<!fir.complex<4>>
-! CHECK:         %[[DIV:.*]] = fir.divc %[[A_VAL]], %[[B_VAL]] : !fir.complex<4>
+! CHECK:         %[[A_REAL:.*]] = fir.extract_value %[[A_VAL]], [0 : index] : (!fir.complex<4>) -> f32
+! CHECK:         %[[A_IMAG:.*]] = fir.extract_value %[[A_VAL]], [1 : index] : (!fir.complex<4>) -> f32
+! CHECK:         %[[B_REAL:.*]] = fir.extract_value %[[B_VAL]], [0 : index] : (!fir.complex<4>) -> f32
+! CHECK:         %[[B_IMAG:.*]] = fir.extract_value %[[B_VAL]], [1 : index] : (!fir.complex<4>) -> f32
+! CHECK:         %[[DIV:.*]] = fir.call @__divsc3(%[[A_REAL]], %[[A_IMAG]], %[[B_REAL]], %[[B_IMAG]]) fastmath<contract> : (f32, f32, f32, f32) -> !fir.complex<4>
 ! CHECK:         fir.store %[[DIV]] to %[[FCTRES]] : !fir.ref<!fir.complex<4>>
 ! CHECK:         %[[RET:.*]] = fir.load %[[FCTRES]] : !fir.ref<!fir.complex<4>>
 ! CHECK:         return %[[RET]] : !fir.complex<4>

diff --git a/flang/test/Lower/complex-operations.f90 b/flang/test/Lower/complex-operations.f90
index b11ce6e..c686671 100644 (file)
--- a/flang/test/Lower/complex-operations.f90
+++ b/flang/test/Lower/complex-operations.f90
@@ -27,11 +27,90 @@ subroutine mul_test(a,b,c)
   a = b * c
 end subroutine mul_test
 
-! CHECK-LABEL: @_QPdiv_test
-subroutine div_test(a,b,c)
-  complex :: a, b, c
-  ! CHECK-NOT: fir.extract_value
-  ! CHECK-NOT: fir.insert_value
-  ! CHECK: fir.divc {{.*}}: !fir.complex
+! CHECK-LABEL: @_QPdiv_test_half
+! CHECK-SAME: %[[AREF:.*]]: !fir.ref<!fir.complex<2>> {{.*}}, %[[BREF:.*]]: !fir.ref<!fir.complex<2>> {{.*}}, %[[CREF:.*]]: !fir.ref<!fir.complex<2>> {{.*}})
+! CHECK: %[[BVAL:.*]] = fir.load %[[BREF]] : !fir.ref<!fir.complex<2>>
+! CHECK: %[[CVAL:.*]] = fir.load %[[CREF]] : !fir.ref<!fir.complex<2>>
+! CHECK: %[[BVAL_CVT:.*]] = fir.convert %[[BVAL]] : (!fir.complex<2>) -> complex<f16>
+! CHECK: %[[CVAL_CVT:.*]] = fir.convert %[[CVAL]] : (!fir.complex<2>) -> complex<f16>
+! CHECK: %[[AVAL_CVT:.*]] = complex.div %[[BVAL_CVT]], %[[CVAL_CVT]] : complex<f16>
+! CHECK: %[[AVAL:.*]] = fir.convert %[[AVAL_CVT]] : (complex<f16>) -> !fir.complex<2>
+! CHECK: fir.store %[[AVAL]] to %[[AREF]] : !fir.ref<!fir.complex<2>>
+subroutine div_test_half(a,b,c)
+  complex(kind=2) :: a, b, c
+  a = b / c
+end subroutine div_test_half
+
+! CHECK-LABEL: @_QPdiv_test_bfloat
+! CHECK-SAME: %[[AREF:.*]]: !fir.ref<!fir.complex<3>> {{.*}}, %[[BREF:.*]]: !fir.ref<!fir.complex<3>> {{.*}}, %[[CREF:.*]]: !fir.ref<!fir.complex<3>> {{.*}})
+! CHECK: %[[BVAL:.*]] = fir.load %[[BREF]] : !fir.ref<!fir.complex<3>>
+! CHECK: %[[CVAL:.*]] = fir.load %[[CREF]] : !fir.ref<!fir.complex<3>>
+! CHECK: %[[BVAL_CVT:.*]] = fir.convert %[[BVAL]] : (!fir.complex<3>) -> complex<bf16>
+! CHECK: %[[CVAL_CVT:.*]] = fir.convert %[[CVAL]] : (!fir.complex<3>) -> complex<bf16>
+! CHECK: %[[AVAL_CVT:.*]] = complex.div %[[BVAL_CVT]], %[[CVAL_CVT]] : complex<bf16>
+! CHECK: %[[AVAL:.*]] = fir.convert %[[AVAL_CVT]] : (complex<bf16>) -> !fir.complex<3>
+! CHECK: fir.store %[[AVAL]] to %[[AREF]] : !fir.ref<!fir.complex<3>>
+subroutine div_test_bfloat(a,b,c)
+  complex(kind=3) :: a, b, c
+  a = b / c
+end subroutine div_test_bfloat
+
+! CHECK-LABEL: @_QPdiv_test_single
+! CHECK-SAME: %[[AREF:.*]]: !fir.ref<!fir.complex<4>> {{.*}}, %[[BREF:.*]]: !fir.ref<!fir.complex<4>> {{.*}}, %[[CREF:.*]]: !fir.ref<!fir.complex<4>> {{.*}})
+! CHECK: %[[BVAL:.*]] = fir.load %[[BREF]] : !fir.ref<!fir.complex<4>>
+! CHECK: %[[CVAL:.*]] = fir.load %[[CREF]] : !fir.ref<!fir.complex<4>>
+! CHECK: %[[BREAL:.*]] = fir.extract_value %[[BVAL]], [0 : index] : (!fir.complex<4>) -> f32
+! CHECK: %[[BIMAG:.*]] = fir.extract_value %[[BVAL]], [1 : index] : (!fir.complex<4>) -> f32
+! CHECK: %[[CREAL:.*]] = fir.extract_value %[[CVAL]], [0 : index] : (!fir.complex<4>) -> f32
+! CHECK: %[[CIMAG:.*]] = fir.extract_value %[[CVAL]], [1 : index] : (!fir.complex<4>) -> f32
+! CHECK: %[[AVAL:.*]] = fir.call @__divsc3(%[[BREAL]], %[[BIMAG]], %[[CREAL]], %[[CIMAG]]) fastmath<contract> : (f32, f32, f32, f32) -> !fir.complex<4>
+! CHECK: fir.store %[[AVAL]] to %[[AREF]] : !fir.ref<!fir.complex<4>>
+subroutine div_test_single(a,b,c)
+  complex(kind=4) :: a, b, c
+  a = b / c
+end subroutine div_test_single
+
+! CHECK-LABEL: @_QPdiv_test_double
+! CHECK-SAME: %[[AREF:.*]]: !fir.ref<!fir.complex<8>> {{.*}}, %[[BREF:.*]]: !fir.ref<!fir.complex<8>> {{.*}}, %[[CREF:.*]]: !fir.ref<!fir.complex<8>> {{.*}})
+! CHECK: %[[BVAL:.*]] = fir.load %[[BREF]] : !fir.ref<!fir.complex<8>>
+! CHECK: %[[CVAL:.*]] = fir.load %[[CREF]] : !fir.ref<!fir.complex<8>>
+! CHECK: %[[BREAL:.*]] = fir.extract_value %[[BVAL]], [0 : index] : (!fir.complex<8>) -> f64
+! CHECK: %[[BIMAG:.*]] = fir.extract_value %[[BVAL]], [1 : index] : (!fir.complex<8>) -> f64
+! CHECK: %[[CREAL:.*]] = fir.extract_value %[[CVAL]], [0 : index] : (!fir.complex<8>) -> f64
+! CHECK: %[[CIMAG:.*]] = fir.extract_value %[[CVAL]], [1 : index] : (!fir.complex<8>) -> f64
+! CHECK: %[[AVAL:.*]] = fir.call @__divdc3(%[[BREAL]], %[[BIMAG]], %[[CREAL]], %[[CIMAG]]) fastmath<contract> : (f64, f64, f64, f64) -> !fir.complex<8>
+! CHECK: fir.store %[[AVAL]] to %[[AREF]] : !fir.ref<!fir.complex<8>>
+subroutine div_test_double(a,b,c)
+  complex(kind=8) :: a, b, c
+  a = b / c
+end subroutine div_test_double
+
+! CHECK-LABEL: @_QPdiv_test_extended
+! CHECK-SAME: %[[AREF:.*]]: !fir.ref<!fir.complex<10>> {{.*}}, %[[BREF:.*]]: !fir.ref<!fir.complex<10>> {{.*}}, %[[CREF:.*]]: !fir.ref<!fir.complex<10>> {{.*}})
+! CHECK: %[[BVAL:.*]] = fir.load %[[BREF]] : !fir.ref<!fir.complex<10>>
+! CHECK: %[[CVAL:.*]] = fir.load %[[CREF]] : !fir.ref<!fir.complex<10>>
+! CHECK: %[[BREAL:.*]] = fir.extract_value %[[BVAL]], [0 : index] : (!fir.complex<10>) -> f80
+! CHECK: %[[BIMAG:.*]] = fir.extract_value %[[BVAL]], [1 : index] : (!fir.complex<10>) -> f80
+! CHECK: %[[CREAL:.*]] = fir.extract_value %[[CVAL]], [0 : index] : (!fir.complex<10>) -> f80
+! CHECK: %[[CIMAG:.*]] = fir.extract_value %[[CVAL]], [1 : index] : (!fir.complex<10>) -> f80
+! CHECK: %[[AVAL:.*]] = fir.call @__divxc3(%[[BREAL]], %[[BIMAG]], %[[CREAL]], %[[CIMAG]]) fastmath<contract> : (f80, f80, f80, f80) -> !fir.complex<10>
+! CHECK: fir.store %[[AVAL]] to %[[AREF]] : !fir.ref<!fir.complex<10>>
+subroutine div_test_extended(a,b,c)
+  complex(kind=10) :: a, b, c
+  a = b / c
+end subroutine div_test_extended
+
+! CHECK-LABEL: @_QPdiv_test_quad
+! CHECK-SAME: %[[AREF:.*]]: !fir.ref<!fir.complex<16>> {{.*}}, %[[BREF:.*]]: !fir.ref<!fir.complex<16>> {{.*}}, %[[CREF:.*]]: !fir.ref<!fir.complex<16>> {{.*}})
+! CHECK: %[[BVAL:.*]] = fir.load %[[BREF]] : !fir.ref<!fir.complex<16>>
+! CHECK: %[[CVAL:.*]] = fir.load %[[CREF]] : !fir.ref<!fir.complex<16>>
+! CHECK: %[[BREAL:.*]] = fir.extract_value %[[BVAL]], [0 : index] : (!fir.complex<16>) -> f128
+! CHECK: %[[BIMAG:.*]] = fir.extract_value %[[BVAL]], [1 : index] : (!fir.complex<16>) -> f128
+! CHECK: %[[CREAL:.*]] = fir.extract_value %[[CVAL]], [0 : index] : (!fir.complex<16>) -> f128
+! CHECK: %[[CIMAG:.*]] = fir.extract_value %[[CVAL]], [1 : index] : (!fir.complex<16>) -> f128
+! CHECK: %[[AVAL:.*]] = fir.call @__divtc3(%[[BREAL]], %[[BIMAG]], %[[CREAL]], %[[CIMAG]]) fastmath<contract> : (f128, f128, f128, f128) -> !fir.complex<16>
+! CHECK: fir.store %[[AVAL]] to %[[AREF]] : !fir.ref<!fir.complex<16>>
+subroutine div_test_quad(a,b,c)
+  complex(kind=16) :: a, b, c
   a = b / c
-end subroutine div_test
+end subroutine div_test_quad