[clang] 9964b0e - [clang] Add -fdump-record-layouts-canonical option

[Steven Wan via cfe-commits]

Author: David Tenty
Date: 2021-07-05T17:35:37-04:00
New Revision: 9964b0ef828b685dc575a50f75bb1780b84b95c8

URL: https://github.com/llvm/llvm-project/commit/9964b0ef828b685dc575a50f75bb1780b84b95c8
DIFF: https://github.com/llvm/llvm-project/commit/9964b0ef828b685dc575a50f75bb1780b84b95c8.diff

LOG: [clang] Add -fdump-record-layouts-canonical option

This option implies -fdump-record-layouts but dumps record layout information with canonical field types, which can be more useful in certain cases when comparing structure layouts.

Reviewed By: stevewan

Differential Revision: https://reviews.llvm.org/D105112

Added: 
    clang/test/Layout/dump-canonical.cpp

Modified: 
    clang/include/clang/Basic/LangOptions.def
    clang/include/clang/Driver/Options.td
    clang/lib/AST/RecordLayoutBuilder.cpp

Removed: 
    


################################################################################
diff  --git a/clang/include/clang/Basic/LangOptions.def b/clang/include/clang/Basic/LangOptions.def
index b18e957a58f4c..8420a97376c38 100644
--- a/clang/include/clang/Basic/LangOptions.def
+++ b/clang/include/clang/Basic/LangOptions.def
@@ -269,6 +269,7 @@ BENIGN_LANGOPT(ModulesDebugInfo , 1, 0, "Modules debug info")
 BENIGN_LANGOPT(ElideConstructors , 1, 1, "C++ copy constructor elision")
 BENIGN_LANGOPT(DumpRecordLayouts , 1, 0, "dumping the layout of IRgen'd records")
 BENIGN_LANGOPT(DumpRecordLayoutsSimple , 1, 0, "dumping the layout of IRgen'd records in a simple form")
+BENIGN_LANGOPT(DumpRecordLayoutsCanonical , 1, 0, "dumping the AST layout of records using canonical field types")
 BENIGN_LANGOPT(DumpRecordLayoutsComplete , 1, 0, "dumping the AST layout of all complete records")
 BENIGN_LANGOPT(DumpVTableLayouts , 1, 0, "dumping the layouts of emitted vtables")
 LANGOPT(NoConstantCFStrings , 1, 0, "no constant CoreFoundation strings")

diff  --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 41b7299b02745..c2b21d9851241 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -5405,13 +5405,16 @@ def stats_file : Joined<["-"], "stats-file=">,
 def fdump_record_layouts_simple : Flag<["-"], "fdump-record-layouts-simple">,
   HelpText<"Dump record layout information in a simple form used for testing">,
   MarshallingInfoFlag<LangOpts<"DumpRecordLayoutsSimple">>;
+def fdump_record_layouts_canonical : Flag<["-"], "fdump-record-layouts-canonical">,
+  HelpText<"Dump record layout information with canonical field types">,
+  MarshallingInfoFlag<LangOpts<"DumpRecordLayoutsCanonical">>;
 def fdump_record_layouts_complete : Flag<["-"], "fdump-record-layouts-complete">,
   HelpText<"Dump record layout information for all complete types">,
   MarshallingInfoFlag<LangOpts<"DumpRecordLayoutsComplete">>;
 def fdump_record_layouts : Flag<["-"], "fdump-record-layouts">,
   HelpText<"Dump record layout information">,
   MarshallingInfoFlag<LangOpts<"DumpRecordLayouts">>,
-  ImpliedByAnyOf<[fdump_record_layouts_simple.KeyPath, fdump_record_layouts_complete.KeyPath]>;
+  ImpliedByAnyOf<[fdump_record_layouts_simple.KeyPath, fdump_record_layouts_complete.KeyPath, fdump_record_layouts_canonical.KeyPath]>;
 def fix_what_you_can : Flag<["-"], "fix-what-you-can">,
   HelpText<"Apply fix-it advice even in the presence of unfixable errors">,
   MarshallingInfoFlag<FrontendOpts<"FixWhatYouCan">>;

diff  --git a/clang/lib/AST/RecordLayoutBuilder.cpp b/clang/lib/AST/RecordLayoutBuilder.cpp
index beb111e2e9718..6ee4178248b92 100644
--- a/clang/lib/AST/RecordLayoutBuilder.cpp
+++ b/clang/lib/AST/RecordLayoutBuilder.cpp
@@ -3577,7 +3577,10 @@ static void DumpRecordLayout(raw_ostream &OS, const RecordDecl *RD,
     } else {
       PrintOffset(OS, FieldOffset, IndentLevel);
     }
-    OS << Field.getType().getAsString() << ' ' << Field << '\n';
+    const QualType &FieldType = C.getLangOpts().DumpRecordLayoutsCanonical
+                                    ? Field.getType().getCanonicalType()
+                                    : Field.getType();
+    OS << FieldType.getAsString() << ' ' << Field << '\n';
   }
 
   // Dump virtual bases.

diff  --git a/clang/test/Layout/dump-canonical.cpp b/clang/test/Layout/dump-canonical.cpp
new file mode 100644
index 0000000000000..c7216169efdd9
--- /dev/null
+++ b/clang/test/Layout/dump-canonical.cpp
@@ -0,0 +1,20 @@
+// RUN: %clang_cc1 -emit-llvm-only -fdump-record-layouts %s | FileCheck %s
+// RUN: %clang_cc1 -emit-llvm-only -fdump-record-layouts-canonical %s | FileCheck %s -check-prefix CANONICAL
+
+typedef long foo_t;
+
+
+struct a {
+  foo_t x;
+} b;
+
+struct c {
+  typedef foo_t bar_t;
+  bar_t x;
+} d;
+
+// CHECK:          0 | foo_t
+// CHECK:          0 | c::bar_t
+// CANONICAL-NOT:  0 | foo_t
+// CANONICAL-NOT:  0 | c::bar_t
+// CANONICAL:      0 | long