Test only reduced BMI

Author: alejandro-alvarez-sonarsource

clang/include/clang/AST/DeclTemplate.h

@@ -1366,6 +1366,8 @@ class NonTypeTemplateParmDecl final
       DefaultArgStorage<NonTypeTemplateParmDecl, TemplateArgumentLoc *>;
   DefArgStorage DefaultArgument;
 
+  bool PlaceholderTypeConstraintInitialized = false;
+
   // FIXME: Collapse this into TemplateParamPosition; or, just move depth/index
   // down here to save memory.
 
@@ -1534,13 +1536,11 @@ class NonTypeTemplateParmDecl final
   /// Return the constraint introduced by the placeholder type of this non-type
   /// template parameter (if any).
   Expr *getPlaceholderTypeConstraint() const {
-    return hasPlaceholderTypeConstraint() ? *getTrailingObjects<Expr *>() :
-        nullptr;
+    return PlaceholderTypeConstraintInitialized ? *getTrailingObjects<Expr *>()
+                                                : nullptr;
   }
 
-  void setPlaceholderTypeConstraint(Expr *E) {
-    *getTrailingObjects<Expr *>() = E;
-  }
+  void setPlaceholderTypeConstraint(Expr *E);
 
   /// Determine whether this non-type template parameter's type has a
   /// placeholder with a type-constraint.

clang/lib/AST/DeclTemplate.cpp

@@ -853,6 +853,16 @@ void NonTypeTemplateParmDecl::setDefaultArgument(
     DefaultArgument.set(new (C) TemplateArgumentLoc(DefArg));
 }
 
+void NonTypeTemplateParmDecl::setPlaceholderTypeConstraint(Expr *E) {
+  assert(hasPlaceholderTypeConstraint() &&
+         "setPlaceholderTypeConstraint called on a NonTypeTemplateParmDecl "
+         "without constraint");
+  assert(!PlaceholderTypeConstraintInitialized && "PlaceholderTypeConstraint "
+                                                  "was already initialized!");
+  *getTrailingObjects<Expr *>() = E;
+  PlaceholderTypeConstraintInitialized = true;
+}
+
 //===----------------------------------------------------------------------===//
 // TemplateTemplateParmDecl Method Implementations
 //===----------------------------------------------------------------------===//

clang/lib/Serialization/ASTReaderDecl.cpp

@@ -2684,7 +2684,7 @@ void ASTDeclReader::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
   // TemplateParmPosition.
   D->setDepth(Record.readInt());
   D->setPosition(Record.readInt());
-  if (D->hasPlaceholderTypeConstraint())
+  if (Record.readBool()) // PlaceholderTypeConstraintInitialized
     D->setPlaceholderTypeConstraint(Record.readExpr());
   if (D->isExpandedParameterPack()) {
     auto TypesAndInfos =

clang/lib/Serialization/ASTWriterDecl.cpp

@@ -1983,15 +1983,17 @@ void ASTDeclWriter::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
   // For an expanded parameter pack, record the number of expansion types here
   // so that it's easier for deserialization to allocate the right amount of
   // memory.
-  Expr *TypeConstraint = D->getPlaceholderTypeConstraint();
-  Record.push_back(!!TypeConstraint);
+  Record.push_back(D->hasPlaceholderTypeConstraint());
   if (D->isExpandedParameterPack())
     Record.push_back(D->getNumExpansionTypes());
 
   VisitDeclaratorDecl(D);
   // TemplateParmPosition.
   Record.push_back(D->getDepth());
   Record.push_back(D->getPosition());
+  Expr *TypeConstraint = D->getPlaceholderTypeConstraint();
+  Record.push_back(/*PlaceholderTypeConstraintInitialized=*/TypeConstraint !=
+                   nullptr);
   if (TypeConstraint)
     Record.AddStmt(TypeConstraint);
 

clang/test/Modules/malformed-constraint-template-non-type-parm-decl.cpp

@@ -5,6 +5,9 @@
 // RUN: %clang_cc1 -std=c++20 mod.cppm -emit-module-interface -o mod.pcm -fallow-pcm-with-compiler-errors -verify
 // RUN: %clang_cc1 -std=c++20 main.cpp -fmodule-file=mod=mod.pcm -verify -fallow-pcm-with-compiler-errors -fsyntax-only -ast-dump-all | FileCheck %s
 
+// RUN: %clang_cc1 -std=c++20 mod.cppm -emit-reduced-module-interface -o mod.pcm -fallow-pcm-with-compiler-errors -verify
+// RUN: %clang_cc1 -std=c++20 main.cpp -fmodule-file=mod=mod.pcm -verify -fallow-pcm-with-compiler-errors -fsyntax-only -ast-dump-all | FileCheck %s
+
 //--- mod.cppm
 export module mod;
 
@@ -29,7 +32,6 @@ import mod;
 
 // CHECK:      |-FunctionTemplateDecl {{.*}} <line:11:1, line:12:22> col:6 imported in mod hidden invalid cos
 // CHECK-NEXT: | |-NonTypeTemplateParmDecl {{.*}} <line:11:10, col:34> col:34 imported in mod hidden referenced invalid 'ReferenceOf<angle> auto' depth 0 index 0 R
-// CHECK-NEXT: | | `-RecoveryExpr {{.*}} <col:10, col:34> 'ReferenceOf<angle> auto' contains-errors lvalue
 // CHECK-NEXT: | |-TemplateTypeParmDecl {{.*}} <col:37, col:46> col:46 imported in mod hidden referenced typename depth 0 index 1 Rep
 // CHECK-NEXT: | |-RequiresExpr {{.*}} <col:60, col:84> 'bool'
 // CHECK-NEXT: | | |-ParmVarDecl {{.*}} <col:69, col:73> col:73 imported in mod hidden referenced v 'Rep'
@@ -42,7 +44,6 @@ import mod;
 
 // CHECK:      |-FunctionTemplateDecl {{.*}} <line:15:1, line:16:22> col:6 imported in mod hidden invalid tan
 // CHECK-NEXT: | |-NonTypeTemplateParmDecl {{.*}} <line:15:10, col:34> col:34 imported in mod hidden referenced invalid 'ReferenceOf<angle> auto' depth 0 index 0 R
-// CHECK-NEXT: | | `-RecoveryExpr {{.*}} <col:10, col:34> 'ReferenceOf<angle> auto' contains-errors lvalue
 // CHECK-NEXT: | |-TemplateTypeParmDecl {{.*}} <col:37, col:46> col:46 imported in mod hidden referenced typename depth 0 index 1 Rep
 // CHECK-NEXT: | |-RequiresExpr {{.*}} <col:60, col:84> 'bool'
 // CHECK-NEXT: | | |-ParmVarDecl {{.*}} <col:69, col:73> col:73 imported in mod hidden referenced v 'Rep'