From b47c88eaefcde1dbfe8d94f62b4eb25851734ffe Mon Sep 17 00:00:00 2001
From: V Donaldson <vdonaldson@nvidia.com>
Date: Wed, 1 Feb 2023 12:52:42 -0800
Subject: [PATCH] [flang] Allow compiler directives in the specification part
 of a module

Lowering code currently allows for directives inside a program or
subprogram, or outside any program unit. Directives may also appear
in the specification part of a module, as in:

module mm
  interface
     subroutine ss(aa)
       !dir$ ignore_tkr(tkr) aa
       integer :: aa(*)
     end subroutine ss
  end interface
end module

With some exceptions such as OpenMP directives, most directives are
currently ignored, so this code should generate an "ignoring all compiler
directives" message.
---
 flang/lib/Lower/PFTBuilder.cpp      | 17 ++++++++++-------
 flang/test/Lower/pre-fir-tree02.f90 |  9 ++++++++-
 2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/flang/lib/Lower/PFTBuilder.cpp b/flang/lib/Lower/PFTBuilder.cpp
index a5f1ed7fb0fd..b9215f5ba2f4 100644
--- a/flang/lib/Lower/PFTBuilder.cpp
+++ b/flang/lib/Lower/PFTBuilder.cpp
@@ -396,7 +396,7 @@ private:
     assert(!evaluationListStack.empty() && "empty evaluation list stack");
     if (!constructAndDirectiveStack.empty())
       eval.parentConstruct = constructAndDirectiveStack.back();
-    auto &entryPointList = eval.getOwningProcedure()->entryPointList;
+    lower::pft::FunctionLikeUnit *owningProcedure = eval.getOwningProcedure();
     evaluationListStack.back()->emplace_back(std::move(eval));
     lower::pft::Evaluation *p = &evaluationListStack.back()->back();
     if (p->isActionStmt() || p->isConstructStmt() || p->isEndStmt() ||
@@ -408,11 +408,14 @@ private:
         p->printIndex = 1;
       }
       lastLexicalEvaluation = p;
-      for (std::size_t entryIndex = entryPointList.size() - 1;
-           entryIndex && !entryPointList[entryIndex].second->lexicalSuccessor;
-           --entryIndex)
-        // Link to the entry's first executable statement.
-        entryPointList[entryIndex].second->lexicalSuccessor = p;
+      if (owningProcedure) {
+        auto &entryPointList = owningProcedure->entryPointList;
+        for (std::size_t entryIndex = entryPointList.size() - 1;
+             entryIndex && !entryPointList[entryIndex].second->lexicalSuccessor;
+             --entryIndex)
+          // Link to the entry's first executable statement.
+          entryPointList[entryIndex].second->lexicalSuccessor = p;
+      }
     } else if (const auto *entryStmt = p->getIf<parser::EntryStmt>()) {
       const semantics::Symbol *sym =
           std::get<parser::Name>(entryStmt->t).symbol;
@@ -420,7 +423,7 @@ private:
         sym = details->specific();
       assert(sym->has<semantics::SubprogramDetails>() &&
              "entry must be a subprogram");
-      entryPointList.push_back(std::pair{sym, p});
+      owningProcedure->entryPointList.push_back(std::pair{sym, p});
     }
     if (p->label.has_value())
       labelEvaluationMap->try_emplace(*p->label, p);
diff --git a/flang/test/Lower/pre-fir-tree02.f90 b/flang/test/Lower/pre-fir-tree02.f90
index 551cd454f8a0..f4fa626ba654 100644
--- a/flang/test/Lower/pre-fir-tree02.f90
+++ b/flang/test/Lower/pre-fir-tree02.f90
@@ -155,6 +155,13 @@ module test
   !![disable]type, extends(a_type) :: b_type
   !![disable]  integer :: y
   !![disable]end type
+  interface
+     subroutine ss(aa)
+       ! CHECK: CompilerDirective
+       !DIR$ IGNORE_TKR aa
+       integer :: aa
+     end subroutine ss
+  end interface
 contains
   ! CHECK: Function foo
   function foo(x)
@@ -212,7 +219,7 @@ contains
   ! CHECK: Subroutine sub
   subroutine sub(a)
     real(4):: a
-    ! CompilerDirective:
+    ! CHECK: CompilerDirective
     !DIR$ IGNORE_TKR a
   end subroutine