[clang] 1ea3266 - DebugInfo: Don't simplify template names using _BitInt(N)

[David Blaikie via cfe-commits]

Author: David Blaikie
Date: 2022-02-15T11:58:40-08:00
New Revision: 1ea326634b582f5574e0b22b85e5b0c631b30dcf

URL: https://github.com/llvm/llvm-project/commit/1ea326634b582f5574e0b22b85e5b0c631b30dcf
DIFF: https://github.com/llvm/llvm-project/commit/1ea326634b582f5574e0b22b85e5b0c631b30dcf.diff

LOG: DebugInfo: Don't simplify template names using _BitInt(N)

_BitInt(N) only encodes the byte size in DWARF, not the bit size, so
can't be reconstituted.

Added: 
    

Modified: 
    clang/lib/CodeGen/CGDebugInfo.cpp
    clang/test/CodeGenCXX/debug-info-simple-template-names.cpp
    cross-project-tests/debuginfo-tests/clang_llvm_roundtrip/simplified_template_names.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index d8ba5592ad478..91a8f278de5c4 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -5032,6 +5032,15 @@ struct ReconstitutableType : public RecursiveASTVisitor<ReconstitutableType> {
     Reconstitutable = false;
     return false;
   }
+  bool VisitType(Type *T) {
+    // _BitInt(N) isn't reconstitutable because the bit width isn't encoded in
+    // the DWARF, only the byte width.
+    if (T->isBitIntType()) {
+      Reconstitutable = false;
+      return false;
+    }
+    return true;
+  }
   bool TraverseEnumType(EnumType *ET) {
     // Unnamed enums can't be reconstituted due to a lack of column info we
     // produce in the DWARF, so we can't get Clang's full name back.

diff  --git a/clang/test/CodeGenCXX/debug-info-simple-template-names.cpp b/clang/test/CodeGenCXX/debug-info-simple-template-names.cpp
index 06e83ea6f59eb..d20c9478c363d 100644
--- a/clang/test/CodeGenCXX/debug-info-simple-template-names.cpp
+++ b/clang/test/CodeGenCXX/debug-info-simple-template-names.cpp
@@ -105,4 +105,10 @@ void f() {
 
   f3<t1>();
   // CHECK: !DISubprogram(name: "_STNf3|<t1>",
+  
+  f1<_BitInt(3)>();
+  // CHECK: !DISubprogram(name: "f1<_BitInt(3)>",
+
+  f1<const unsigned _BitInt(5)>();
+  // CHECK: !DISubprogram(name: "f1<const unsigned _BitInt(5)>",
 }

diff  --git a/cross-project-tests/debuginfo-tests/clang_llvm_roundtrip/simplified_template_names.cpp b/cross-project-tests/debuginfo-tests/clang_llvm_roundtrip/simplified_template_names.cpp
index 898b27ec0e479..ee429ef3b5798 100644
--- a/cross-project-tests/debuginfo-tests/clang_llvm_roundtrip/simplified_template_names.cpp
+++ b/cross-project-tests/debuginfo-tests/clang_llvm_roundtrip/simplified_template_names.cpp
@@ -316,6 +316,8 @@ int main() {
   f1<void(t8)>();
   operator_not_really<int>();
   t12 v4;
+  f1<_BitInt(3)>();
+  f1<const unsigned _BitInt(5)>();
 }
 void t8::mem() {
   struct t7 { };