[flang-commits] [flang] bfcd053 - [flang][hlfir] Do not emit extra declare for dummy used in BLOCK (#69184)

[via flang-commits]

Author: jeanPerier
Date: 2023-10-17T09:11:53+02:00
New Revision: bfcd05317d0fbe90474eda13a4dbf33c2cee4130

URL: https://github.com/llvm/llvm-project/commit/bfcd05317d0fbe90474eda13a4dbf33c2cee4130
DIFF: https://github.com/llvm/llvm-project/commit/bfcd05317d0fbe90474eda13a4dbf33c2cee4130.diff

LOG: [flang][hlfir] Do not emit extra declare for dummy used in BLOCK (#69184)

When a variable is used in a specification expression in a scope, it is
added to the list of variables that must be instantiated when lowering
the scope. When lowering a BLOCK, this caused instantiateVar to be
called again on all the host block variables appearing in block variable
specification expressions. This caused an extra declare to be emitted
for dummy inside block (for non dummy, instantiateVar is a no-op if the
symbol is already mapped).

Only call instantiateVar if the symbol is not mapped when lowering BLOCK
variables.

Added: 
    flang/test/Lower/HLFIR/convert-variable-block.f90

Modified: 
    flang/lib/Lower/Bridge.cpp

Removed: 
    


################################################################################
diff  --git a/flang/lib/Lower/Bridge.cpp b/flang/lib/Lower/Bridge.cpp
index ef8540c35a37286..f26a1aaf0236fa5 100644
--- a/flang/lib/Lower/Bridge.cpp
+++ b/flang/lib/Lower/Bridge.cpp
@@ -2610,8 +2610,12 @@ class FirConverter : public Fortran::lower::AbstractConverter {
         scopeBlockIdMap.try_emplace(&scope, ++blockId);
         Fortran::lower::AggregateStoreMap storeMap;
         for (const Fortran::lower::pft::Variable &var :
-             Fortran::lower::pft::getScopeVariableList(scope))
-          instantiateVar(var, storeMap);
+             Fortran::lower::pft::getScopeVariableList(scope)) {
+          // Do no instantiate again variables from the block host
+          // that appears in specification of block variables.
+          if (!var.hasSymbol() || !lookupSymbol(var.getSymbol()))
+            instantiateVar(var, storeMap);
+        }
       } else if (e.getIf<Fortran::parser::EndBlockStmt>()) {
         if (eval.lowerAsUnstructured())
           maybeStartBlock(e.block);

diff  --git a/flang/test/Lower/HLFIR/convert-variable-block.f90 b/flang/test/Lower/HLFIR/convert-variable-block.f90
new file mode 100644
index 000000000000000..30f8eacaaed17bd
--- /dev/null
+++ b/flang/test/Lower/HLFIR/convert-variable-block.f90
@@ -0,0 +1,25 @@
+! Test that hlfir.declare is not created again for dummy arguments
+! used in specifications of BLOCK variables.
+! RUN: bbc -emit-hlfir %s -o - | FileCheck %s
+
+subroutine test(n)
+  integer(8) :: n
+  call before_block()
+  block
+    real :: x(n)
+    call foo(x)
+  end block
+end subroutine
+! CHECK-LABEL:   func.func @_QPtest(
+! CHECK-SAME:                       %[[VAL_0:.*]]: !fir.ref<i64> {fir.bindc_name = "n"}) {
+! CHECK:           %[[VAL_1:.*]]:2 = hlfir.declare %[[VAL_0]] {uniq_name = "_QFtestEn"} : (!fir.ref<i64>) -> (!fir.ref<i64>, !fir.ref<i64>)
+! CHECK:           fir.call @_QPbefore_block() {{.*}}: () -> ()
+! CHECK:           %[[VAL_3:.*]] = fir.load %[[VAL_1]]#0 : !fir.ref<i64>
+! CHECK:           %[[VAL_4:.*]] = fir.convert %[[VAL_3]] : (i64) -> index
+! CHECK:           %[[VAL_5:.*]] = arith.constant 0 : index
+! CHECK:           %[[VAL_6:.*]] = arith.cmpi sgt, %[[VAL_4]], %[[VAL_5]] : index
+! CHECK:           %[[VAL_7:.*]] = arith.select %[[VAL_6]], %[[VAL_4]], %[[VAL_5]] : index
+! CHECK:           %[[VAL_8:.*]] = fir.alloca !fir.array<?xf32>, %[[VAL_7]] {bindc_name = "x", uniq_name = "_QFtestB1Ex"}
+! CHECK:           %[[VAL_9:.*]] = fir.shape %[[VAL_7]] : (index) -> !fir.shape<1>
+! CHECK:           %[[VAL_10:.*]]:2 = hlfir.declare %[[VAL_8]](%[[VAL_9]]) {uniq_name = "_QFtestB1Ex"} : (!fir.ref<!fir.array<?xf32>>, !fir.shape<1>) -> (!fir.box<!fir.array<?xf32>>, !fir.ref<!fir.array<?xf32>>)
+! CHECK:           fir.call @_QPfoo(%[[VAL_10]]#1) {{.*}}: (!fir.ref<!fir.array<?xf32>>) -> ()