[flang-commits] [flang] 4eab303 - [flang][hlfir] Fixed symbol lookup for character returns.

[Slava Zakharin via flang-commits]

Author: Slava Zakharin
Date: 2023-05-17T08:59:33-07:00
New Revision: 4eab303404d6bb2252b4baf807c5ac87a0fa3125

URL: https://github.com/llvm/llvm-project/commit/4eab303404d6bb2252b4baf807c5ac87a0fa3125
DIFF: https://github.com/llvm/llvm-project/commit/4eab303404d6bb2252b4baf807c5ac87a0fa3125.diff

LOG: [flang][hlfir] Fixed symbol lookup for character returns.

Symbols corresponding to entries returning character results
must be mapped to EmboxCharOp, first, before we can map them
to DeclareOp. The code may be reworked after HLFIR is enabled
by default, but right now it seems like an acceptable solution to me.

Differential Revision: https://reviews.llvm.org/D150749

Added: 
    

Modified: 
    flang/lib/Lower/Bridge.cpp
    flang/test/Lower/HLFIR/function-return.f90

Removed: 
    


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diff  --git a/flang/lib/Lower/Bridge.cpp b/flang/lib/Lower/Bridge.cpp
index 875f8624e4487..19ae9576dfac2 100644
--- a/flang/lib/Lower/Bridge.cpp
+++ b/flang/lib/Lower/Bridge.cpp
@@ -857,6 +857,20 @@ class FirConverter : public Fortran::lower::AbstractConverter {
             },
             [](auto x) -> Fortran::lower::SymbolBox { return x; });
       }
+
+      // Entry character result represented as an argument pair
+      // needs to be represented in the symbol table even before
+      // we can create DeclareOp for it. The temporary mapping
+      // is EmboxCharOp that conveys the address and length information.
+      // After mapSymbolAttributes is done, the mapping is replaced
+      // with the new DeclareOp, and the following table lookups
+      // do not reach here.
+      if (sym.IsFuncResult())
+        if (const Fortran::semantics::DeclTypeSpec *declTy = sym.GetType())
+          if (declTy->category() ==
+              Fortran::semantics::DeclTypeSpec::Category::Character)
+            return symMap->lookupSymbol(sym);
+
       // Procedure dummies are not mapped with an hlfir.declare because
       // they are not "variable" (cannot be assigned to), and it would
       // make hlfir.declare more complex than it needs to to allow this.

diff  --git a/flang/test/Lower/HLFIR/function-return.f90 b/flang/test/Lower/HLFIR/function-return.f90
index dbabb0597ab64..a4ceed55d3354 100644
--- a/flang/test/Lower/HLFIR/function-return.f90
+++ b/flang/test/Lower/HLFIR/function-return.f90
@@ -42,3 +42,29 @@ integer function array_return()
 ! CHECK:  %[[VAL_4:.*]]:2 = hlfir.declare %[[VAL_2]]{{.*}} {uniq_name = "_QFchar_array_returnEchar_array_return"} : (!fir.ref<!fir.array<10x!fir.char<1,5>>>, !fir.shape<1>, index) -> (!fir.ref<!fir.array<10x!fir.char<1,5>>>, !fir.ref<!fir.array<10x!fir.char<1,5>>>)
 ! CHECK:  %[[VAL_5:.*]] = fir.load %[[VAL_4]]#1 : !fir.ref<!fir.array<10x!fir.char<1,5>>>
 ! CHECK:  return %[[VAL_5]] : !fir.array<10x!fir.char<1,5>>
+
+character*(*) function char_var_len_return()
+  character*(*) char_var_len_return2
+  entry char_var_len_return2
+end function char_var_len_return
+! CHECK-LABEL:   func.func @_QPchar_var_len_return(
+! CHECK-SAME:                                      %[[VAL_0:.*]]: !fir.ref<!fir.char<1,?>>,
+! CHECK-SAME:                                      %[[VAL_1:.*]]: index) -> !fir.boxchar<1> {
+! CHECK:           %[[VAL_2:.*]]:2 = hlfir.declare %[[VAL_0]] typeparams %[[VAL_1]] {uniq_name = "_QFchar_var_len_returnEchar_var_len_return"} : (!fir.ref<!fir.char<1,?>>, index) -> (!fir.boxchar<1>, !fir.ref<!fir.char<1,?>>)
+! CHECK:           %[[VAL_3:.*]]:2 = hlfir.declare %[[VAL_0]] typeparams %[[VAL_1]] {uniq_name = "_QFchar_var_len_returnEchar_var_len_return2"} : (!fir.ref<!fir.char<1,?>>, index) -> (!fir.boxchar<1>, !fir.ref<!fir.char<1,?>>)
+! CHECK:           cf.br ^bb1
+! CHECK:         ^bb1:
+! CHECK:           %[[VAL_4:.*]] = fir.emboxchar %[[VAL_2]]#1, %[[VAL_1]] : (!fir.ref<!fir.char<1,?>>, index) -> !fir.boxchar<1>
+! CHECK:           return %[[VAL_4]] : !fir.boxchar<1>
+! CHECK:         }
+
+! CHECK-LABEL:   func.func @_QPchar_var_len_return2(
+! CHECK-SAME:                                       %[[VAL_0:.*]]: !fir.ref<!fir.char<1,?>>,
+! CHECK-SAME:                                       %[[VAL_1:.*]]: index) -> !fir.boxchar<1> {
+! CHECK:           %[[VAL_2:.*]]:2 = hlfir.declare %[[VAL_0]] typeparams %[[VAL_1]] {uniq_name = "_QFchar_var_len_returnEchar_var_len_return"} : (!fir.ref<!fir.char<1,?>>, index) -> (!fir.boxchar<1>, !fir.ref<!fir.char<1,?>>)
+! CHECK:           %[[VAL_3:.*]]:2 = hlfir.declare %[[VAL_0]] typeparams %[[VAL_1]] {uniq_name = "_QFchar_var_len_returnEchar_var_len_return2"} : (!fir.ref<!fir.char<1,?>>, index) -> (!fir.boxchar<1>, !fir.ref<!fir.char<1,?>>)
+! CHECK:           cf.br ^bb1
+! CHECK:         ^bb1:
+! CHECK:           %[[VAL_4:.*]] = fir.emboxchar %[[VAL_3]]#1, %[[VAL_1]] : (!fir.ref<!fir.char<1,?>>, index) -> !fir.boxchar<1>
+! CHECK:           return %[[VAL_4]] : !fir.boxchar<1>
+! CHECK:         }