[flang] Create a temporary of the correct size when lowering SetLength

This patch creates a temporary of the appropriate length while lowering SetLength.

The corresponding character can be truncated or padded if necessary.

This fix issue with array constructor in argument and also with statement function.

```
  character(7) :: str = "1234567"
  call s(str(1:1))
contains
 subroutine s(a)
  character(*) :: a
  call s2([Character(3)::a])
 end subroutine
 subroutine s2(c)
  character(3) :: c(1)
  print "(4a)", c(1), "end"
 end subroutine
end
```

The example prior the patch prints `123end` instead of `1. end`

Reviewed By: PeteSteinfeld, jeanPerier

Differential Revision: https://reviews.llvm.org/D132464

diff --git a/flang/lib/Lower/ConvertExpr.cpp b/flang/lib/Lower/ConvertExpr.cpp
index ac22207..6fb1ca2 100644 (file)
--- a/flang/lib/Lower/ConvertExpr.cpp
+++ b/flang/lib/Lower/ConvertExpr.cpp
@@ -1315,7 +1315,11 @@ public:
   ExtValue genval(const Fortran::evaluate::SetLength<KIND> &x) {
     mlir::Value newLenValue = genunbox(x.right());
     fir::ExtendedValue lhs = gen(x.left());
-    return replaceScalarCharacterLength(lhs, newLenValue);
+    fir::factory::CharacterExprHelper charHelper(builder, getLoc());
+    fir::CharBoxValue temp = charHelper.createCharacterTemp(
+        charHelper.getCharacterType(fir::getBase(lhs).getType()), newLenValue);
+    charHelper.createAssign(temp, lhs);
+    return fir::ExtendedValue{temp};
   }
 
   template <int KIND>

diff --git a/flang/test/Lower/statement-function.f90 b/flang/test/Lower/statement-function.f90
index b59b8fb..c672332 100644 (file)
--- a/flang/test/Lower/statement-function.f90
+++ b/flang/test/Lower/statement-function.f90
@@ -101,6 +101,7 @@ integer function test_stmt_character(c, j)
   test_stmt_character = func(c, j)
 end function
 
+
 ! Test statement function with a character actual argument whose
 ! length may be different than the dummy length (the dummy length
 ! must be used inside the statement function).
@@ -145,3 +146,34 @@ subroutine bug247(r)
   PRINT *, I(2.5)
   ! CHECK: fir.call {{.*}}EndIo
 END subroutine bug247
+
+! Test that the argument is truncated to the length of the dummy argument.
+subroutine truncate_arg
+  character(4) arg
+  character(10) stmt_fct
+  stmt_fct(arg) = arg
+  print *, stmt_fct('longer_arg')
+end subroutine
+
+! CHECK-LABEL: @_QPtruncate_arg
+! CHECK: %[[c4:.*]] = arith.constant 4 : i32
+! CHECK: %[[arg:.*]] = fir.address_of(@_QQcl.{{.*}}) : !fir.ref<!fir.char<1,10>>
+! CHECK: %[[cast_arg:.*]] = fir.convert %[[arg]] : (!fir.ref<!fir.char<1,10>>) -> !fir.ref<!fir.char<1,?>>
+! CHECK: %[[c10:.*]] = arith.constant 10 : i64
+! CHECK: %[[temp:.*]] = fir.alloca !fir.char<1,10> {bindc_name = ".chrtmp"}
+! CHECK: %[[c10_index:.*]] = fir.convert %[[c10]] : (i64) -> index
+! CHECK: %[[c4_index:.*]] = fir.convert %[[c4]] : (i32) -> index
+! CHECK: %[[cmpi:.*]] = arith.cmpi slt, %[[c10_index]], %[[c4_index]] : index
+! CHECK: %[[select:.*]] = arith.select %[[cmpi]], %[[c10_index]], %[[c4_index]] : index
+! CHECK: %[[c1:.*]] = arith.constant 1 : i64
+! CHECK: %[[select_i64:.*]] = fir.convert %[[select]] : (index) -> i64
+! CHECK: %[[length:.*]] = arith.muli %[[c1]], %[[select_i64]] : i64
+! CHECK: %[[cast_temp_i8:.*]] = fir.convert %[[temp]] : (!fir.ref<!fir.char<1,10>>) -> !fir.ref<i8>
+! CHECK: %[[cast_arg_i8:.*]] = fir.convert %[[cast_arg]] : (!fir.ref<!fir.char<1,?>>) -> !fir.ref<i8>
+! CHECK: fir.call @llvm.memmove.p0.p0.i64(%[[cast_temp_i8]], %[[cast_arg_i8]], %[[length]], %{{.*}}) : (!fir.ref<i8>, !fir.ref<i8>, i64, i1) -> ()
+! CHECK: %[[c1_i64:.*]] = arith.constant 1 : i64
+! CHECK: %[[ub:.*]] = arith.subi %[[c10]], %[[c1_i64]] : i64
+! CHECK: %[[ub_index:.*]] = fir.convert %[[ub]] : (i64) -> index
+! CHECK: fir.do_loop %{{.*}} = %[[select]] to %[[ub_index]] step %{{.*}} {
+! CHECK: %[[cast_temp:.*]] = fir.convert %[[temp:.*]] : (!fir.ref<!fir.char<1,10>>) -> !fir.ref<i8>
+! CHECK: %{{.*}} = fir.call @_FortranAioOutputAscii(%{{.*}}, %[[cast_temp]], %[[c10]]) : (!fir.ref<i8>, !fir.ref<i8>, i64) -> i1