[clang-tools-extra] [clangd] Show alignment for records and fields decls (PR #67213)

[via cfe-commits]

https://github.com/sr-tream updated https://github.com/llvm/llvm-project/pull/67213

>From df0b44379ab2a4ba50458db0979bddff67c3e4b5 Mon Sep 17 00:00:00 2001
From: SR_team <me at sr.team>
Date: Sat, 23 Sep 2023 03:49:23 +0300
Subject: [PATCH] [clangd] Show alignment for records and fields decls

---
 clang-tools-extra/clangd/Hover.cpp                |  5 +++++
 clang-tools-extra/clangd/Hover.h                  |  2 ++
 clang-tools-extra/clangd/unittests/HoverTests.cpp | 11 +++++++++++
 3 files changed, 18 insertions(+)

diff --git a/clang-tools-extra/clangd/Hover.cpp b/clang-tools-extra/clangd/Hover.cpp
index 0ec85fc24df151b..ef35232110fbfce 100644
--- a/clang-tools-extra/clangd/Hover.cpp
+++ b/clang-tools-extra/clangd/Hover.cpp
@@ -1001,6 +1001,8 @@ void addLayoutInfo(const NamedDecl &ND, HoverInfo &HI) {
   if (auto *RD = llvm::dyn_cast<RecordDecl>(&ND)) {
     if (auto Size = Ctx.getTypeSizeInCharsIfKnown(RD->getTypeForDecl()))
       HI.Size = Size->getQuantity() * 8;
+    if (!RD->isDependentType())
+      HI.Align = Ctx.getTypeAlign(RD->getTypeForDecl());
     return;
   }
 
@@ -1009,6 +1011,7 @@ void addLayoutInfo(const NamedDecl &ND, HoverInfo &HI) {
     if (Record)
       Record = Record->getDefinition();
     if (Record && !Record->isInvalidDecl() && !Record->isDependentType()) {
+      HI.Align = Ctx.getTypeAlign(FD->getType());
       const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(Record);
       HI.Offset = Layout.getFieldOffset(FD->getFieldIndex());
       if (FD->isBitField())
@@ -1488,6 +1491,8 @@ markup::Document HoverInfo::present() const {
           llvm::formatv(" (+{0} padding)", formatSize(*Padding)).str());
     }
   }
+  if (Align)
+    Output.addParagraph().appendText("Align: " + formatSize(*Align));
 
   if (CalleeArgInfo) {
     assert(CallPassType);
diff --git a/clang-tools-extra/clangd/Hover.h b/clang-tools-extra/clangd/Hover.h
index 6a61100912918ea..fe689de44732ebe 100644
--- a/clang-tools-extra/clangd/Hover.h
+++ b/clang-tools-extra/clangd/Hover.h
@@ -97,6 +97,8 @@ struct HoverInfo {
   std::optional<uint64_t> Offset;
   /// Contains the padding following a field within the enclosing class.
   std::optional<uint64_t> Padding;
+  /// Contains the alignment of fields and types where it's interesting.
+  std::optional<uint64_t> Align;
   // Set when symbol is inside function call. Contains information extracted
   // from the callee definition about the argument this is passed as.
   std::optional<Param> CalleeArgInfo;
diff --git a/clang-tools-extra/clangd/unittests/HoverTests.cpp b/clang-tools-extra/clangd/unittests/HoverTests.cpp
index 8c88cd52574536c..c5623759a7c2041 100644
--- a/clang-tools-extra/clangd/unittests/HoverTests.cpp
+++ b/clang-tools-extra/clangd/unittests/HoverTests.cpp
@@ -92,6 +92,7 @@ TEST(Hover, Structured) {
          HI.Offset = 0;
          HI.Size = 8;
          HI.Padding = 56;
+         HI.Align = 8;
          HI.AccessSpecifier = "private";
        }},
       // Union field
@@ -110,6 +111,7 @@ TEST(Hover, Structured) {
          HI.Type = "char";
          HI.Size = 8;
          HI.Padding = 120;
+         HI.Align = 8;
          HI.AccessSpecifier = "public";
        }},
       // Bitfield
@@ -128,6 +130,7 @@ TEST(Hover, Structured) {
          HI.Type = "int";
          HI.Offset = 0;
          HI.Size = 1;
+         HI.Align = 32;
          HI.AccessSpecifier = "public";
        }},
       // Local to class method.
@@ -192,6 +195,7 @@ TEST(Hover, Structured) {
          HI.Type = "char";
          HI.Offset = 0;
          HI.Size = 8;
+         HI.Align = 8;
          HI.AccessSpecifier = "public";
        }},
       // Struct definition shows size.
@@ -204,6 +208,7 @@ TEST(Hover, Structured) {
          HI.Kind = index::SymbolKind::Struct;
          HI.Definition = "struct X {}";
          HI.Size = 8;
+         HI.Align = 8;
        }},
       // Variable with template type
       {R"cpp(
@@ -1375,6 +1380,7 @@ class Foo final {})cpp";
          HI.Offset = 8;
          HI.Size = 1;
          HI.Padding = 23;
+         HI.Align = 8;
          HI.AccessSpecifier = "public";
        }}};
   for (const auto &Case : Cases) {
@@ -1411,6 +1417,7 @@ class Foo final {})cpp";
     EXPECT_EQ(H->Value, Expected.Value);
     EXPECT_EQ(H->Size, Expected.Size);
     EXPECT_EQ(H->Offset, Expected.Offset);
+    EXPECT_EQ(H->Align, Expected.Align);
     EXPECT_EQ(H->AccessSpecifier, Expected.AccessSpecifier);
     EXPECT_EQ(H->CalleeArgInfo, Expected.CalleeArgInfo);
     EXPECT_EQ(H->CallPassType, Expected.CallPassType);
@@ -3448,6 +3455,7 @@ template <typename T, typename C = bool> class Foo {})",
             HI.Size = 32;
             HI.Offset = 96;
             HI.Padding = 32;
+            HI.Align = 32;
           },
           R"(field foo
 
@@ -3455,6 +3463,7 @@ Type: type (aka can_type)
 Value = value
 Offset: 12 bytes
 Size: 4 bytes (+4 bytes padding)
+Align: 4 bytes
 
 // In test::Bar
 def)",
@@ -3470,6 +3479,7 @@ def)",
             HI.Size = 25;
             HI.Offset = 35;
             HI.Padding = 4;
+            HI.Align = 64;
           },
           R"(field foo
 
@@ -3477,6 +3487,7 @@ Type: type (aka can_type)
 Value = value
 Offset: 4 bytes and 3 bits
 Size: 25 bits (+4 bits padding)
+Align: 8 bytes
 
 // In test::Bar
 def)",