DebugInfo: Use clang's preferred names for integer types

This reverts c7f16ab / r109694 - which
suggested this was done to improve consistency with the gdb test suite.
Possible that at the time GCC did not canonicalize integer types, and so
matching types was important for cross-compiler validity, or that it was
only a case of over-constrained test cases that printed out/tested the
exact names of integer types.

In any case neither issue seems to exist today based on my limited
testing - both gdb and lldb canonicalize integer types (in a way that
happens to match Clang's preferred naming, incidentally) and so never
print the original text name produced in the DWARF by GCC or Clang.

This canonicalization appears to be in `integer_types_same_name_p` for
GDB and in `TypeSystemClang::GetBasicTypeEnumeration` for lldb.

(I tested this with one translation unit defining 3 variables - `long`,
`long (*)()`, and `int (*)()`, and another translation unit that had
main, and a function that took `long (*)()` as a parameter - then
compiled them with mismatched compilers (either GCC+Clang, or
Clang+(Clang with this patch applied)) and no matter the combination,
despite the debug info for one CU naming the type "long int" and the
other naming it "long", both debuggers printed out the name as "long"
and were able to correctly perform overload resolution and pass the
`long int (*)()` variable to the `long (*)()` function parameter)

Did find one hiccup, identified by the lldb test suite - that CodeView
was relying on these names to map them to builtin types in that format.
So added some handling for that in LLVM. (these could be split out into
separate patches, but seems small enough to not warrant it - will do
that if there ends up needing any reverti/revisiting)

Differential Revision: https://reviews.llvm.org/D110455

clang/lib/CodeGen/CGDebugInfo.cpp

@@ -873,23 +873,7 @@ llvm::DIType *CGDebugInfo::CreateType(const BuiltinType *BT) {
     break;
   }
 
-  switch (BT->getKind()) {
-  case BuiltinType::Long:
-    BTName = "long int";
-    break;
-  case BuiltinType::LongLong:
-    BTName = "long long int";
-    break;
-  case BuiltinType::ULong:
-    BTName = "long unsigned int";
-    break;
-  case BuiltinType::ULongLong:
-    BTName = "long long unsigned int";
-    break;
-  default:
-    BTName = BT->getName(CGM.getLangOpts());
-    break;
-  }
+  BTName = BT->getName(CGM.getLangOpts());
   // Bit size and offset of the type.
   uint64_t Size = CGM.getContext().getTypeSize(BT);
   return DBuilder.createBasicType(BTName, Size, Encoding);

clang/test/CodeGen/aarch64-debug-sve-vector-types.c

@@ -46,12 +46,12 @@ void test_locals(void) {
 
   // CHECK-DAG: name: "__SVInt64_t",{{.*}}, baseType: ![[CT64:[0-9]+]]
   // CHECK-DAG: ![[CT64]] = !DICompositeType(tag: DW_TAG_array_type, baseType: ![[ELTTY64:[0-9]+]], flags: DIFlagVector, elements: ![[ELTS1_64]])
-  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "long int", size: 64, encoding: DW_ATE_signed)
+  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "long", size: 64, encoding: DW_ATE_signed)
   __SVInt64_t s64;
 
   // CHECK-DAG: name: "__SVUint64_t",{{.*}}, baseType: ![[CT64:[0-9]+]]
   // CHECK-DAG: ![[CT64]] = !DICompositeType(tag: DW_TAG_array_type, baseType: ![[ELTTY64:[0-9]+]], flags: DIFlagVector, elements: ![[ELTS1_64]])
-  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "long unsigned int", size: 64, encoding: DW_ATE_unsigned)
+  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "unsigned long", size: 64, encoding: DW_ATE_unsigned)
   __SVUint64_t u64;
 
   // CHECK:     name: "__SVFloat16_t",{{.*}}, baseType: ![[CT16:[0-9]+]]

clang/test/CodeGen/aarch64-debug-sve-vectorx2-types.c

@@ -40,14 +40,14 @@ void test_locals(void) {
 
   // CHECK-DAG: name: "__clang_svint64x2_t",{{.*}}, baseType: ![[CT64:[0-9]+]]
   // CHECK-DAG: ![[CT64]] = !DICompositeType(tag: DW_TAG_array_type, baseType: ![[ELTTY64:[0-9]+]], flags: DIFlagVector, elements: ![[ELTS1x2_64:[0-9]+]])
-  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "long int", size: 64, encoding: DW_ATE_signed)
+  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "long", size: 64, encoding: DW_ATE_signed)
   // CHECK-DAG: ![[ELTS1x2_64]] = !{![[REALELTS1x2_64:[0-9]+]]}
   // CHECK-DAG: ![[REALELTS1x2_64]] = !DISubrange(lowerBound: 0, upperBound: !DIExpression(DW_OP_constu, 2, DW_OP_bregx, 46, 0, DW_OP_mul, DW_OP_constu, 1, DW_OP_minus))
   __clang_svint64x2_t s64;
 
   // CHECK-DAG: name: "__clang_svuint64x2_t",{{.*}}, baseType: ![[CT64:[0-9]+]]
   // CHECK-DAG: ![[CT64]] = !DICompositeType(tag: DW_TAG_array_type, baseType: ![[ELTTY64:[0-9]+]], flags: DIFlagVector, elements: ![[ELTS1x2_64]])
-  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "long unsigned int", size: 64, encoding: DW_ATE_unsigned)
+  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "unsigned long", size: 64, encoding: DW_ATE_unsigned)
   __clang_svuint64x2_t u64;
 
   // CHECK:     name: "__clang_svfloat16x2_t",{{.*}}, baseType: ![[CT16:[0-9]+]]

clang/test/CodeGen/aarch64-debug-sve-vectorx3-types.c

@@ -40,14 +40,14 @@ void test_locals(void) {
 
   // CHECK-DAG: name: "__clang_svint64x3_t",{{.*}}, baseType: ![[CT64:[0-9]+]]
   // CHECK-DAG: ![[CT64]] = !DICompositeType(tag: DW_TAG_array_type, baseType: ![[ELTTY64:[0-9]+]], flags: DIFlagVector, elements: ![[ELTS1x3_64:[0-9]+]])
-  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "long int", size: 64, encoding: DW_ATE_signed)
+  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "long", size: 64, encoding: DW_ATE_signed)
   // CHECK-DAG: ![[ELTS1x3_64]] = !{![[REALELTS1x3_64:[0-9]+]]}
   // CHECK-DAG: ![[REALELTS1x3_64]] = !DISubrange(lowerBound: 0, upperBound: !DIExpression(DW_OP_constu, 3, DW_OP_bregx, 46, 0, DW_OP_mul, DW_OP_constu, 1, DW_OP_minus))
   __clang_svint64x3_t s64;
 
   // CHECK-DAG: name: "__clang_svuint64x3_t",{{.*}}, baseType: ![[CT64:[0-9]+]]
   // CHECK-DAG: ![[CT64]] = !DICompositeType(tag: DW_TAG_array_type, baseType: ![[ELTTY64:[0-9]+]], flags: DIFlagVector, elements: ![[ELTS1x3_64]])
-  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "long unsigned int", size: 64, encoding: DW_ATE_unsigned)
+  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "unsigned long", size: 64, encoding: DW_ATE_unsigned)
   __clang_svuint64x3_t u64;
 
   // CHECK:     name: "__clang_svfloat16x3_t",{{.*}}, baseType: ![[CT16:[0-9]+]]

clang/test/CodeGen/aarch64-debug-sve-vectorx4-types.c

@@ -40,14 +40,14 @@ void test_locals(void) {
 
   // CHECK-DAG: name: "__clang_svint64x4_t",{{.*}}, baseType: ![[CT64:[0-9]+]]
   // CHECK-DAG: ![[CT64]] = !DICompositeType(tag: DW_TAG_array_type, baseType: ![[ELTTY64:[0-9]+]], flags: DIFlagVector, elements: ![[ELTS1x4_64:[0-9]+]])
-  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "long int", size: 64, encoding: DW_ATE_signed)
+  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "long", size: 64, encoding: DW_ATE_signed)
   // CHECK-DAG: ![[ELTS1x4_64]] = !{![[REALELTS1x4_64:[0-9]+]]}
   // CHECK-DAG: ![[REALELTS1x4_64]] = !DISubrange(lowerBound: 0, upperBound: !DIExpression(DW_OP_constu, 4, DW_OP_bregx, 46, 0, DW_OP_mul, DW_OP_constu, 1, DW_OP_minus))
   __clang_svint64x4_t s64;
 
   // CHECK-DAG: name: "__clang_svuint64x4_t",{{.*}}, baseType: ![[CT64:[0-9]+]]
   // CHECK-DAG: ![[CT64]] = !DICompositeType(tag: DW_TAG_array_type, baseType: ![[ELTTY64:[0-9]+]], flags: DIFlagVector, elements: ![[ELTS1x4_64]])
-  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "long unsigned int", size: 64, encoding: DW_ATE_unsigned)
+  // CHECK-DAG: ![[ELTTY64]] = !DIBasicType(name: "unsigned long", size: 64, encoding: DW_ATE_unsigned)
   __clang_svuint64x4_t u64;
 
   // CHECK:     name: "__clang_svfloat16x4_t",{{.*}}, baseType: ![[CT16:[0-9]+]]

clang/test/CodeGen/debug-info-enum.cpp

@@ -77,7 +77,7 @@ enum class E6 : signed long long {
 // CHECK-SAME: baseType: ![[LONG:[0-9]+]]
 // CHECK-SAME: DIFlagEnumClass
 // CHECK-SAME: elements: ![[ELTS6:[0-9]+]]
-// CHECK: ![[LONG]] = !DIBasicType(name: "long long int", size: 64, encoding: DW_ATE_signed)
+// CHECK: ![[LONG]] = !DIBasicType(name: "long long", size: 64, encoding: DW_ATE_signed)
 // CHECK: ![[ELTS6]] = !{![[A6:[0-9]+]], ![[B6:[0-9]+]]}
 // CHECK: ![[A6]] = !DIEnumerator(name: "A6", value: -9223372036854775808)
 // CHECK: ![[B6]] = !DIEnumerator(name: "B6", value: 9223372036854775807)
@@ -87,7 +87,7 @@ enum class E7 : unsigned long long { A7 = 18446744073709551615ULL } x7;
 // CHECK-SAME: baseType: ![[ULONG:[0-9]+]]
 // CHECK-SAME: DIFlagEnumClass
 // CHECK-SAME: elements: ![[ELTS7:[0-9]+]]
-// CHECK: ![[ULONG]] = !DIBasicType(name: "long long unsigned int", size: 64, encoding: DW_ATE_unsigned)
+// CHECK: ![[ULONG]] = !DIBasicType(name: "unsigned long long", size: 64, encoding: DW_ATE_unsigned)
 // CHECK: ![[ELTS7]] = !{![[A7:[0-9]+]]}
 // CHECK: ![[A7]] = !DIEnumerator(name: "A7", value: 18446744073709551615, isUnsigned: true)
 

clang/test/CodeGen/debug-info.c

@@ -58,3 +58,8 @@ __uint128_t foo128 ()
 typedef unsigned long long uint64_t;
 typedef uint64_t uint64x2_t __attribute__((ext_vector_type(2)));
 uint64x2_t extvectbar[4];
+
+// CHECK-DAG: !DIBasicType(name: "long"
+// CHECK-DAG: !DIBasicType(name: "unsigned long long"
+void integral_types(long x, unsigned long long y) {
+}

clang/test/CodeGenCXX/debug-info-enum-class.cpp

@@ -25,7 +25,7 @@ D d;
 // CHECK-NOT:              offset:
 // CHECK-SAME:             flags: DIFlagEnumClass
 // CHECK-SAME:             ){{$}}
-// CHECK: ![[ULONG]] = !DIBasicType(name: "long unsigned int"
+// CHECK: ![[ULONG]] = !DIBasicType(name: "unsigned long"
 // CHECK: !DICompositeType(tag: DW_TAG_enumeration_type, name: "C"
 // CHECK-SAME:             line: 5
 // CHECK-SAME:             baseType: ![[ULONG:[0-9]+]]

clang/test/CodeGenObjC/objc-fixed-enum.m

@@ -54,7 +54,7 @@ int main() {
 // CHECK: ![[ENUMERATOR3]] = !DIDerivedType(tag: DW_TAG_typedef, name: "NSInteger"
 // CHECK-SAME:                              line: 6
 // CHECK-SAME:                              baseType: ![[LONGINT:[0-9]+]]
-// CHECK: ![[LONGINT]] = !DIBasicType(name: "long int"
+// CHECK: ![[LONGINT]] = !DIBasicType(name: "long"
 // CHECK: ![[ENUMERATOR2:[0-9]+]] = !DICompositeType(tag: DW_TAG_enumeration_type,
 // CHECK-SAME:                                       line: 22
 // CHECK-SAME:                                       baseType: ![[ENUMERATOR3]]

lldb/test/Shell/SymbolFile/DWARF/x86/find-basic-variable.cpp

@@ -45,9 +45,9 @@ int foo;
 namespace bar {
 int context;
 long foo;
-// NAME-DAG: name = "foo", type = {{.*}} (long int), {{.*}} decl = find-basic-variable.cpp:[[@LINE-1]]
-// CONTEXT-DAG: name = "foo", type = {{.*}} (long int), {{.*}} decl = find-basic-variable.cpp:[[@LINE-2]]
-// REGEX-DAG: name = "foo", type = {{.*}} (long int), {{.*}} decl = find-basic-variable.cpp:[[@LINE-3]]
+// NAME-DAG: name = "foo", type = {{.*}} (long), {{.*}} decl = find-basic-variable.cpp:[[@LINE-1]]
+// CONTEXT-DAG: name = "foo", type = {{.*}} (long), {{.*}} decl = find-basic-variable.cpp:[[@LINE-2]]
+// REGEX-DAG: name = "foo", type = {{.*}} (long), {{.*}} decl = find-basic-variable.cpp:[[@LINE-3]]
 namespace baz {
 static short foo;
 // NAME-DAG: name = "foo", type = {{.*}} (short), {{.*}} decl = find-basic-variable.cpp:[[@LINE-1]]

llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp

@@ -1729,9 +1729,14 @@ TypeIndex CodeViewDebug::lowerTypeBasic(const DIBasicType *Ty) {
   }
 
   // Apply some fixups based on the source-level type name.
-  if (STK == SimpleTypeKind::Int32 && Ty->getName() == "long int")
+  // Include some amount of canonicalization from an old naming scheme Clang
+  // used to use for integer types (in an outdated effort to be compatible with
+  // GCC's debug info/GDB's behavior, which has since been addressed).
+  if (STK == SimpleTypeKind::Int32 &&
+      (Ty->getName() == "long int" || Ty->getName() == "long"))
     STK = SimpleTypeKind::Int32Long;
-  if (STK == SimpleTypeKind::UInt32 && Ty->getName() == "long unsigned int")
+  if (STK == SimpleTypeKind::UInt32 && (Ty->getName() == "long unsigned int" ||
+                                        Ty->getName() == "unsigned long"))
     STK = SimpleTypeKind::UInt32Long;
   if (STK == SimpleTypeKind::UInt16Short &&
       (Ty->getName() == "wchar_t" || Ty->getName() == "__wchar_t"))

llvm/test/CodeGen/MIR/X86/diexpr-win32.mir

@@ -128,7 +128,7 @@
   !15 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "string", file: !1, line: 1, size: 96, elements: !16, identifier: ".?AUstring@@")
   !16 = !{!17, !19, !20}
   !17 = !DIDerivedType(tag: DW_TAG_member, name: "length", scope: !15, file: !1, line: 2, baseType: !18, size: 32)
-  !18 = !DIBasicType(name: "long int", size: 32, encoding: DW_ATE_signed)
+  !18 = !DIBasicType(name: "long", size: 32, encoding: DW_ATE_signed)
   !19 = !DIDerivedType(tag: DW_TAG_member, name: "size", scope: !15, file: !1, line: 3, baseType: !18, size: 32, offset: 32)
   !20 = !DIDerivedType(tag: DW_TAG_member, name: "data", scope: !15, file: !1, line: 4, baseType: !21, size: 32, offset: 64)
   !21 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !22, size: 32)

llvm/test/DebugInfo/COFF/types-basic.ll

@@ -675,12 +675,12 @@ attributes #3 = { nounwind uwtable "disable-tail-calls"="false" "less-precise-fp
 !46 = !DIDerivedType(tag: DW_TAG_ptr_to_member_type, baseType: !41, size: 64, extraData: !37)
 !47 = !DILocation(line: 12, column: 13, scope: !7)
 !48 = !DILocalVariable(name: "l1", scope: !7, file: !1, line: 13, type: !49)
-!49 = !DIBasicType(name: "long int", size: 32, align: 32, encoding: DW_ATE_signed)
+!49 = !DIBasicType(name: "long", size: 32, align: 32, encoding: DW_ATE_signed)
 !50 = !DILocation(line: 13, column: 8, scope: !7)
 !51 = !DILocalVariable(name: "l2", scope: !7, file: !1, line: 14, type: !49)
 !52 = !DILocation(line: 14, column: 12, scope: !7)
 !53 = !DILocalVariable(name: "l3", scope: !7, file: !1, line: 15, type: !54)
-!54 = !DIBasicType(name: "long unsigned int", size: 32, align: 32, encoding: DW_ATE_unsigned)
+!54 = !DIBasicType(name: "unsigned long", size: 32, align: 32, encoding: DW_ATE_unsigned)
 !55 = !DILocation(line: 15, column: 17, scope: !7)
 !56 = !DILocalVariable(name: "l4", scope: !7, file: !1, line: 16, type: !54)
 !57 = !DILocation(line: 16, column: 21, scope: !7)

llvm/test/DebugInfo/COFF/types-integer-old.ll

@@ -0,0 +1,77 @@
+; RUN: llc < %s -filetype=obj | llvm-readobj - --codeview | FileCheck %s
+
+; Tests that CodeView integer types are generated even when using Clang's old integer type names.
+
+; C++ source to regenerate:
+; $ cat t.cpp
+; void usevars(long, ...);
+; void f() {
+;   long l1 = 0;
+;   unsigned long l2 = 0;
+;   usevars(l1, l2);
+; }
+; $ clang t.cpp -S -emit-llvm -g -gcodeview -o t.ll  -target x86_64-pc-windows-msvc19.0.23918
+
+; CHECK:     LocalSym {
+; CHECK:       Type: long (0x12)
+; CHECK:       VarName: l1
+; CHECK:     }
+; CHECK:     LocalSym {
+; CHECK:       Type: unsigned long (0x22)
+; CHECK:       VarName: l2
+; CHECK:     }
+
+; ModuleID = '/usr/local/google/home/blaikie/dev/scratch/t.cpp'
+source_filename = "/usr/local/google/home/blaikie/dev/scratch/t.cpp"
+target datalayout = "e-m:w-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-pc-windows-msvc19.0.23918"
+
+; Function Attrs: mustprogress noinline optnone uwtable
+define dso_local void @"?f@@YAXXZ"() #0 !dbg !8 {
+entry:
+  %l1 = alloca i32, align 4
+  %l2 = alloca i32, align 4
+  call void @llvm.dbg.declare(metadata i32* %l1, metadata !13, metadata !DIExpression()), !dbg !15
+  store i32 0, i32* %l1, align 4, !dbg !15
+  call void @llvm.dbg.declare(metadata i32* %l2, metadata !16, metadata !DIExpression()), !dbg !18
+  store i32 0, i32* %l2, align 4, !dbg !18
+  %0 = load i32, i32* %l2, align 4, !dbg !19
+  %1 = load i32, i32* %l1, align 4, !dbg !19
+  call void (i32, ...) @"?usevars@@YAXJZZ"(i32 %1, i32 %0), !dbg !19
+  ret void, !dbg !20
+}
+
+; Function Attrs: nofree nosync nounwind readnone speculatable willreturn
+declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
+
+declare dso_local void @"?usevars@@YAXJZZ"(i32, ...) #2
+
+attributes #0 = { mustprogress noinline optnone uwtable "frame-pointer"="none" "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+attributes #1 = { nofree nosync nounwind readnone speculatable willreturn }
+attributes #2 = { "frame-pointer"="none" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!2, !3, !4, !5, !6}
+!llvm.ident = !{!7}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang version 14.0.0 (git@github.com:llvm/llvm-project.git 3709fb72c86bea1f0e6c51ab334ed6417cbe1c07)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, splitDebugInlining: false, nameTableKind: None)
+!1 = !DIFile(filename: "/usr/local/google/home/blaikie/dev/scratch/t.cpp", directory: "/usr/local/google/home/blaikie/dev/llvm/src", checksumkind: CSK_MD5, checksum: "a8e7ccc989ea91d67d3cb95afa046aa5")
+!2 = !{i32 2, !"CodeView", i32 1}
+!3 = !{i32 2, !"Debug Info Version", i32 3}
+!4 = !{i32 1, !"wchar_size", i32 2}
+!5 = !{i32 7, !"PIC Level", i32 2}
+!6 = !{i32 7, !"uwtable", i32 1}
+!7 = !{!"clang version 14.0.0 (git@github.com:llvm/llvm-project.git 3709fb72c86bea1f0e6c51ab334ed6417cbe1c07)"}
+!8 = distinct !DISubprogram(name: "f", linkageName: "?f@@YAXXZ", scope: !9, file: !9, line: 2, type: !10, scopeLine: 2, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !12)
+!9 = !DIFile(filename: "scratch/t.cpp", directory: "/usr/local/google/home/blaikie/dev", checksumkind: CSK_MD5, checksum: "a8e7ccc989ea91d67d3cb95afa046aa5")
+!10 = !DISubroutineType(types: !11)
+!11 = !{null}
+!12 = !{}
+!13 = !DILocalVariable(name: "l1", scope: !8, file: !9, line: 3, type: !14)
+!14 = !DIBasicType(name: "long int", size: 32, encoding: DW_ATE_signed)
+!15 = !DILocation(line: 3, scope: !8)
+!16 = !DILocalVariable(name: "l2", scope: !8, file: !9, line: 4, type: !17)
+!17 = !DIBasicType(name: "long unsigned int", size: 32, encoding: DW_ATE_unsigned)
+!18 = !DILocation(line: 4, scope: !8)
+!19 = !DILocation(line: 5, scope: !8)
+!20 = !DILocation(line: 6, scope: !8)