[flang] Add specific TODO for the REDUCE instrinsic

[clementval]

Summary

Add a proper TODO for the REDUCE instrinsic instead of crashing.

[vdonaldson]

flang/lib/Lower/IntrinsicCall.cpp

3703

There are development scripts that check for categories of TODO messages in test runs. It would be best to try to match that. For this case that would be

intrinsic: reduce

[PeteSteinfeld]

I agree with Val's comments. Please make that change to flang/lib/Lower/IntrinsicCall.cpp before pushing. Otherwise, all build, tests, and looks good.

[clementval]

Change TODO message to match other intrinsic TODOs

[vdonaldson]

Thanks Valentin

flang/lib/Lower/IntrinsicCall.cpp

struct IntrinsicLibrary {
   fir::ExtendedValue genPack(mlir::Type, llvm::ArrayRef<fir::ExtendedValue>);
   mlir::Value genPopcnt(mlir::Type, llvm::ArrayRef<mlir::Value>);
   mlir::Value genPoppar(mlir::Type, llvm::ArrayRef<mlir::Value>);
   fir::ExtendedValue genPresent(mlir::Type, llvm::ArrayRef<fir::ExtendedValue>);
   fir::ExtendedValue genProduct(mlir::Type, llvm::ArrayRef<fir::ExtendedValue>);
   void genRandomInit(llvm::ArrayRef<fir::ExtendedValue>);
   void genRandomNumber(llvm::ArrayRef<fir::ExtendedValue>);
   void genRandomSeed(llvm::ArrayRef<fir::ExtendedValue>);
+  fir::ExtendedValue genReduce(mlir::Type, llvm::ArrayRef<fir::ExtendedValue>);
   fir::ExtendedValue genRepeat(mlir::Type, llvm::ArrayRef<fir::ExtendedValue>);
   fir::ExtendedValue genReshape(mlir::Type, llvm::ArrayRef<fir::ExtendedValue>);
   mlir::Value genRRSpacing(mlir::Type resultType,
                            llvm::ArrayRef<mlir::Value> args);
   mlir::Value genScale(mlir::Type, llvm::ArrayRef<mlir::Value>);
   fir::ExtendedValue genScan(mlir::Type, llvm::ArrayRef<fir::ExtendedValue>);
   mlir::Value genSelectedIntKind(mlir::Type, llvm::ArrayRef<mlir::Value>);
   mlir::Value genSelectedRealKind(mlir::Type, llvm::ArrayRef<mlir::Value>);
static constexpr IntrinsicHandler handlers[]{
      {{{"harvest", asBox}}},
      /*isElemental=*/false},
     {"random_seed",
      &I::genRandomSeed,
      {{{"size", asBox, handleDynamicOptional},
        {"put", asBox, handleDynamicOptional},
        {"get", asBox, handleDynamicOptional}}},
      /*isElemental=*/false},
+    {"reduce",
+     &I::genReduce,
+     {{{"array", asBox},
+       {"operation", asAddr},
+       {"dim", asValue},
+       {"mask", asBox, handleDynamicOptional},
+       {"identity", asValue},
+       {"ordered", asValue}}},
+     /*isElemental=*/false},
     {"repeat",
      &I::genRepeat,
      {{{"string", asAddr}, {"ncopies", asValue}}},
      /*isElemental=*/false},
     {"reshape",
      &I::genReshape,
      {{{"source", asBox},
        {"shape", asBox},
return isStaticallyPresent(args[i])
                : builder.create<fir::AbsentOp>(loc, boxNoneTy).getResult();
   };
   mlir::Value size = getDesc(0);
   mlir::Value put = getDesc(1);
   mlir::Value get = getDesc(2);
   Fortran::lower::genRandomSeed(builder, loc, size, put, get);
 }
 
+// REDUCE
+fir::ExtendedValue
+IntrinsicLibrary::genReduce(mlir::Type resultType,
+                            llvm::ArrayRef<fir::ExtendedValue> args) {
+  TODO(loc, "intrinsic: reduce");
+}
+
 // REPEAT
 fir::ExtendedValue
 IntrinsicLibrary::genRepeat(mlir::Type resultType,
                             llvm::ArrayRef<fir::ExtendedValue> args) {
   assert(args.size() == 2);
   mlir::Value string = builder.createBox(loc, args[0]);
   mlir::Value ncopies = fir::getBase(args[1]);
   // Create mutable fir.box to be passed to the runtime for the result.

flang/test/Lower/Intrinsics/Todo/reduce.f90

+! RUN: %not_todo_cmd bbc -emit-fir %s -o -  2>&1 | FileCheck %s
+
+interface
+  pure function chfunc(a,b)
+    character(*),intent(in) :: a,b
+    character(3) :: chfunc
+  end function
+  end interface
+  character(3) x(5)
+  print*, reduce(x,chfunc)
+end program
+
+! CHECK: not yet implemented: intrinsic: reduce